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Country · Asia

Thailand

Every profile recorded in Thailand, native or introduced.

Species
243
Families
28
Genera
92
Found only here
33
Photographed
243 of 243

Where it isAsia

Shares its fishes withspecies recorded in both

Found only here33

33 of these profiles carry Thailand and no other country. That is not the same as endemic. Most of these distributions are only half recorded.

Male individual from the U.S. aquarium trade.

Abbottina rivularisChinese False Gudgeon

Cyprinidae · Basilewsky, 1855

Max length
150mm SL6in SL
Tank
150 × 45cm60 × 18in
Temp
16–24°C61–75°F
pH
6.0–8.0

Native to continental China, the Korean peninsula, and southern Japan. Type locality is given only as 'Lakes and rivers, northern China', with the type series possibly originating from the Pai-ho River near Beijing. It has been widely introduced and is considered invasive elsewhere, including the Mekong river basin (records from Laos and Thailand), Salween river (Myanmar), northern Japan, Taiwan, Turkmeni...

Moderate
It's unclear whether A. molobrion has yet been seen in the trade.

Acanthopsoides molobrion

Cobitidae · Siebert, 1991

Max length
50mm SL2.0in SL
Tank
60 × 30cm24 × 12in
Temp
20–24°C68–75°F
pH
5.5–7.0

Acanthopsoides spp. are most closely related to the horse-faced loaches of the genus Acantopsis with which they often co-occur in nature, and thus commonly referred to as 'dwarf horse-face loaches'. The genus currently comprises five species of which four were described by Siebert (1991); these were discovered in existing museum holdings...

Easy
Subadult specimen of A. choirorhynchos (?).

Acantopsis dialuzonaHorseface Loach

Cobitidae · van Hasselt, 1823

Max length
200mm SL8in SL
Tank
120 × 45cm48 × 18in
Temp
16–24°C61–75°F
pH
6.0–8.0

Juveniles of this 'species' (probably a group of species - see 'distribution') are traded in large numbers but it's still uncommon to see adult specimens in the hobby suggesting their needs are not catered for often enough. This is a shame as when maintained properly they're hardy, long-lived and interesting aquarium residents. Other trade names include 'long-nosed' and 'banana' loach. Please note although certain that more than one species is being tr...

Easy
We're unsure whether this species has been seen in the aquarium trade.

Acrochordonichthys gyrinusFalcate Chameleon Catfish

Akysidae · Vidthayanon & Ng, 2003

Max length
80mm SL3.1in SL
Tank
75 × 30cm30 × 12in
Temp
17.5–24°C64–75°F
pH
5.0–7.0

As in other members of the genus body colouration in this species is variable, even among individuals collected from a single locality, although a few regularities have been observed which can be used to distinguish certain species from one another. This is thought related to the fact that Acrochordonichthys spp. periodically shed their skins and appear paler post-moulting.

Easy
This species exhibits highly variable body colouration which can range from dark...

Acrochordonichthys rugosusAsian Banjo Catfish

Akysidae · Bleeker, 1846

Max length
110mm SL4in SL
Tank
90 × 30cm36 × 12in
Temp
17.5–24°C64–75°F
pH
5.0–7.0

This is the most commonly-encountered representative of the genus in the aquatic trade though is by no means common. As in other members of the genus body colouration is highly variable, even among individuals collected from a single locality, although a few useful regularities have been observed which can be used to distinguish certain species. This is thought related to the fact that Acrochordonichthys spp. periodically shed their skins and appear paler post-moulting. A. rugosus lends its ...

Moderate
This species is virtually unknown in the aquarium trade.

Acrochordonichthys septentrionalisMae Klong Chameleon Catfish

Akysidae · Ng & Ng, 2001

Max length
100mm SL3.9in SL
Tank
90 × 30cm36 × 12in
Temp
17.5–24°C64–75°F
pH
5.0–7.0

As in other members of the genus body colouration in this species is variable, even among individuals collected from a single locality, although a few regularities have been observed which can be used to distinguish certain species from one another. This is thought related to the fact that Acrochordonichthys spp. periodically shed their skins and appear paler post-moulting.

Moderate
Specimen from southern Thailand.

Akysis hendricksoniHendrickson's Stream Catfish

Akysidae · Alfred, 1966

Max length
50mm SL2.0in SL
Tank
45 × 30cm18 × 12in
Temp
16.5–24°C62–75°F
pH
6.0–7.2

This species is among the few members of the family to have been exported for the aquarium hobby. It can be differentiated from all other Akysis species by the following combination of characters: head length 17.7-26.5% of standard length (SL); head width 25.4-28.7% SL; body depth at anus 13.0-17.0% SL; caudal peduncle depth 8.1-10.1% SL; interorbital di...

Easy
Wild specimen collected from Chanthaburi province, eastern Thailand.

Akysis maculipinnisSpotfin Stream Catfish

Akysidae · Fowler, 1934

Max length
35mm SL1.4in SL
Tank
45 × 30cm18 × 12in
Temp
16.5–24°C62–75°F
pH
6.0–7.5

This species has been exported for the aquarium hobby and ranks among the smaller members of the family. It can be differentiated from all other Akysis species by the following combination of characters: head length 22.0-28.6% of standard length (SL); caudal peduncle depth 8.8-10.7% of SL; anal-fin base length 15.2-19.1% of SL; eye diameter 12-16% of head length (HL); nasal barbel length 57 92% of HL; posession of 3-4 serrae on the posterior edge ofspine; body patterning mottled with indistinct ...

Easy
This species has entered the trade in limited numbers.

Akysis pulvinatusKra Stream Catfish

Akysidae · Ng, 2007

Max length
30mm SL1.2in SL
Tank
45 × 30cm18 × 12in
Temp
16.5–23.5°C62–74°F
pH
6.0–7.2

This species has been exported for the aquarium hobby on an extremely limited basis. It can be differentiated from all other Akysis species by the following combination of characters: head length 27.6–29.8% of standard length (SL); head width 21.9–25.1% SL; caudal peduncle depth 9.4–10.3% SL; length ofbase 23.0–25.2% SL; nasal barbel len...

Easy
Individual in the aquarium.

Akysis variusVariable Stream Catfish

Akysidae · Ng & Kottelat, 1998

Max length
40mm SL1.6in SL
Tank
45 × 30cm18 × 12in
Temp
16.5–24°C62–75°F
pH
6.0–7.5

This species is among the smaller members of the family. It can be differentiated from all other Akysis species by the following combination of characters: caudal peduncle length 16.1-19.8% of standard length (SL); caudal peduncle depth 6.5-9.3% SL; length of adipose-fin base 25.6-29.5% SL; interorbital distance 42.0-46.0% of head length (HL), eye diameter 13.0-20.0% HL; length of nasal barbel 44.0-66.0% HL; lateral margins of the head appear straight when viewed from above; possession of 0-5 se...

Easy
Specimen collected in Thailand.

Akysis vespaOrange-Banded Stream Catfish

Akysidae · Ng & Kottelat, 2004

Max length
31mm SL1.2in SL
Tank
45 × 30cm18 × 12in
Temp
16.5–23.5°C62–74°F
pH
6.0–7.5

This species is among the few members of the family to be exported for the aquarium hobby and we've also seen it on sale under various names such as 'orange-banded stone catfish', 'orange micro bumblebee catfish', 'Burmese orange mini bee catfish' or more simply 'wasp catfish'. Though the majority of forms are yellowish to orange in colouration there appears to exist a bright red variant which to date we've only seen in photos.

Easy
Adult, probably male, specimen.

Ambastaia nigrolineataBlack-Lined Loach

Botiidae · Kottelat & Chu, 1987

Max length
80mm SL3.1in SL
Tank
90 × 30cm36 × 12in
Temp
20–25°C68–77°F
pH
6.5–7.5

This specie is relatively rare in the aquarium trade and much sought after by enthusiasts as a result. It looks relatively similar to A. sidthimunki but according to the original description by Kottelat and Chu (1987) can be told apart by colour patterning which uniquely consists of a solid da...

Moderate
Well-marked adult female specimen.

Ambastaia sidthimunkiDwarf Chain Loach

Botiidae · Klausewitz, 1959

Max length
60mm SL2.4in SL
Tank
80 × 30cm31 × 12in
Temp
20–30°C68–86°F
pH
5.5–7.5

This species was lost to the hobby for several years prior to the turn of the century and when commercially-produced stock first came onto the market prices were very high. It's now readily available, though, and while never particularly cheap is considerably less expensive.

Easy
Adult male individual in the aquarium.

Amblypharyngodon chulabhornaePrincess Carplet

Cyprinidae · Vidthayanon & Kottelat, 1990

Max length
40mm SL1.6in SL
Tank
90 × 30cm36 × 12in
Temp
18–28°C64–82°F
pH
6.0–8.0

The genus Amblypharyngodon currently contains five valid species, and A. chulabhornae can be distinguished from congeners by the following combination of characters: 42-50 (vs. 50-79) scales in the lateral row; lateral line incomplete with 6-7 (vs. 7-23) perforated scales; 4-5 scales on a transverse row between the lateral line and pelvic-fin base. All members of the genus lack barbels.

Easy
Male of Badis khwae.

Badis khwae

Badidae · Kullander & Britz, 2002

Max length
60mm SL2.4in SL
Tank
60 × 30cm24 × 12in
Temp
22–26°C72–79°F
pH
6.5–7.5

Like most badids this species is poorly documented and has yet to find significant popularity in the aquarium hobby, though given its restricted natural distribution it is unlikely ever to be available in large numbers. Within the genus it is most easily confused with B. ruber and B. siamensis but both these species have rows of dark spot-like markings on the flanks which are lacking in B. khwae. The three also differ in the shape of the dark marking on the caudal peduncle; in B. ruber it is rel...

Moderate
Adult specimen; neutral colour pattern.

Badis siamensis

Badidae · Klausewitz, 1957

Max length
60mm SL2.4in SL
Tank
60 × 30cm24 × 12in
Temp
22–26°C72–79°F
pH
6.5–7.5

Like most badids this species is poorly documented and has yet to find significant popularity in the aquarium hobby; to date it has only been exported in very limited numbers. It was for a number of years known as Badis badis siamensis and will be seen labelled as such in older literature. Within the genus it is most easily confused with B. khwae and B. ruber but can be identified by the flank patterning which consists of rows of horizontally-arranged dark markings. In B. ruber these appear mor...

Moderate
This species is rarely-seen in the aquarium trade.

Bagrichthys majusculusWhite-Whisker Lancer

Bagridae · Ng, 2002

Max length
177mm SL7in SL
Tank
120 × 45cm48 × 18in
Temp
24–28°C75–82°F
pH
5.5–7.0

The vernacular name 'lancer' is derived from the extended dorsal spine possessed by several members of the genus, which currently contains 7 species. Among them B. majusculus is most similar to B. macracanthus and B. vaillantii but can be told apart from both by possession of longer pectoral-fin spines (length 15.8 - 20.7 % SL vs. 11.5 - 16.2 %), from the former by possession of a larger adipose fi...

Easy
This species is rare in the aquarium trade.

Bagrichthys obscurus

Bagridae · Ng, 1999

Max length
249mm SL10in SL
Tank
120 × 45cm48 × 18in
Temp
24–28°C75–82°F
pH
5.5–7.0

The vernacular name 'lancer' is derived from the extended dorsal spine possessed by several members of the genus, which currently contains 7 species. B. obscurus is diagnosable from congerners by the following combination of characters: mouth opening relatively small and narrow; oral dentition significantly reduced; dorsal-fin spi...

Easy
Head detail with keeled scales clearly visible.

Balitoropsis zollingeri

Balitoridae · Bleeker, 1853

Max length
70mm SL2.8in SL
Tank
60 × 30cm24 × 12in
Temp
20–25.5°C68–78°F
pH
6.0–7.5

An obligate dweller of swiftly-flowing streams and headwaters containing clear, oxygen-saturated water. It often inhabits riffles and runs and is likely to show a preference for shallower zones. Substrates are generally composed of gravel, rocks, boulders or bedrock carpeted with a rich biofilm formed by algae and other micro-organisms. Juveniles are often found in slower-moving stretches with gravel substrate and submerged tree roots. In both cases patches of aquatic plants are only occasionally pres...

Moderate
Adult specimen from eastern Thailand.

Barbodes aurotaeniatus

Cyprinidae · Tirant, 1885

Max length
65mm SL2.6in SL
Tank
80 × 30cm31 × 12in
Temp
18–26°C64–79°F
pH
6.0–7.5

B. aurotaeniatus is uncommon in the aquarium trade. Following Kottelat (1998) it has a single pair of maxillary barbels, a complete lateral line and colour pattern usually comprising four small, vertically-orientated black markings on the flanks (located above anterior lateral line origin, below dorsal-fin origin, below posterior end of dorsal-fin base and on caudal peduncle, respectively) and one on the dorsal surface, below dorsal-fin origin.

Easy
Individual from Kedah state, northern Peninsular Malaysia.

Barbodes binotatusSpotted Barb

Cyprinidae · Valenciennes, 1842

Max length
200mm SL8in SL
Tank
120 × 45cm48 × 18in
Temp
18–30°C64–86°F
pH
6.0–7.5

This species is so ubiquitous across its natural range that it's often referred to simply as 'common barb'. Basic adult colour pattern consists of a small, dark spot at the base of the dorsal-fin origin and another on the caudal peduncle but overall appearance varies somewhat depending on origin, with the anterior dark spot enlarged ventrally forming a bar or posterior spot extending into the caudal-fin, for example. The spots may also appear darker or lighter in some individuals.

Easy
Subadult from the Singapore aquarium trade.

Barbodes lateristrigaSpanner Barb

Cyprinidae · Valenciennes, 1842

Max length
150mm SL6in SL
Tank
150 × 45cm60 × 18in
Temp
20–28°C68–82°F
pH
6.0–8.0

This species is commonly-referred to as 'T-barb' in some countries. It's closely-affiliated with and sometimes traded as the congener B. kuchingensis but that species can be told apart by colour pattern comprising a prominent row of dark spots along the lateral line, plus a short, horizontally-orientated streak extending from the upper part of the operculum. In B. lateristriga the lateral markings usually form a solid stripe and there is no streak extending from the operculum.

Moderate
Subadult specimen.

Barbonymus altusRed-tailed Tinfoil Barb

Cyprinidae · Günther, 1868

Max length
210mm SL8in SL
Tank
150 × 60cm60 × 24in
Temp
20–27°C68–81°F
pH
6.0–8.0

This is one of two species sold with the common/trade name of "tinfoil barb", the other being the more widely-recognised B. schwanenfeldii. Despite this it appears that B. altus is just as widely available as B. schwanenfeldii and in many cases is seen on sale more regularly. Unfortunately both are usually offered at a small size (usually around 2 - 3"/5 - 7.5cm) with little to no information regarding the eventual size of the fish. Although B. altus is the ...

Moderate
Adult specimen.

Barbonymus gonionotus

Cyprinidae · Bleeker, 1849

Max length
300mm SL12in SL
Tank
210 × 60cm84 × 24in
Temp
20–26°C68–79°F
pH
6.0–8.0

The genus Barbonymus was erected by Kottelat in 1999 and contains former members of Barbodes from southeast Asia. The type species is B. schwanenfeldii and currently there exist only three other representatives; B. altus, B. collingwoodii and B. gonionotus. The latter two are rare in the hobby although an SF member has kept B. gonionotus in the past so they are worth looking out for if you harbour an...

Moderate
Adult individual from Thailand in the aquarium.

Barbonymus schwanefeldiiTinfoil barb

Cyprinidae · Bleeker, 1854

Max length
355mm SL14in SL
Tank
210 × 60cm84 × 24in
Temp
20–28°C68–82°F
pH
6.0–8.0

This is one of two species traded under the vernacular name 'tinfoil barb', the other being the less well-known congener B. altus. Despite this it appears that B. altus is just as widely available as B. schwanefeldii and in many cases is seen on sale more regularly. Unfortunately both are usually offered at a small size (usually around 50 - 75 mm) with little to no information regarding the eventual size of the fish.

Moderate
Specimen from the portion of the Ataran River located in Thailand, where it's known as the Kasat...

Batasio feruminatus

Bagridae · Ng & Kottelat, 2008

Max length
60mm SL2.4in SL
Tank
90 × 30cm36 × 12in
Temp
16–24°C61–75°F
pH
6.0–7.0

Batasio spp. are obligate inhabitants of headwater streams and the upper reaches of smaller rivers characterised by shallow, fast-flowing, highly-oxygenated stretches of riffles and runs broken up by pools or cascades in some cases. Images of the Ataran correspondingly depict flowing sections of forest-shaded, seemingly well-oxygenated headwaters containing clear water, a mixed sand/rock substrate and lots of submerged driftwood/leaf litter.

Moderate
Adult specimen from southern Thailand.

Batasio fluviatilis

Bagridae · Day, 1888

Max length
72mm SL2.8in SL
Tank
120 × 30cm48 × 12in
Temp
16–24°C61–75°F
pH
6.0–7.0

Batasio havmolleri (Smith, 1931) is currently considered a junior synonym of B. fluviatilis. Members of the genus Batasio are characterised by the following combination of characters; laterally-compressed body shape; presence of large sensory pores on the head; a narrow mental region; a pair of prominent posterior proces...

Moderate
This species is poorly known in the aquarium hobby.

Batasio tigrinus

Bagridae · Ng & Kottelat, 2001

Max length
80mm SL3.1in SL
Tank
120 × 30cm48 × 12in
Temp
17–23°C63–73°F
pH
6.0–7.0

Members of the genus Batasio are characterised by the following combination of characters; laterally-compressed body shape; presence of large sensory pores on the head; a narrow mental region; a pair of prominent posterior processes on the anterior portion of the vomer; a transversely elongated, bar-like entopterygoid; close contact between the metapterygoid and quadrate.

Moderate
Adult male individual from Perak state, Peninsular Malaysia.

Belontia hasseltiJava Combtail

Osphronemidae · Cuvier, 1831

Max length
200mm SL8in SL
Tank
120 × 30cm48 × 12in
Temp
21–26°C70–79°F
pH
4.5–8.5

This species is also referred to by the vernacular name 'Malay combtail'. In terms of external characters it differs most obviously from its only congener, B. signata by its overal brownish grey (vs. reddish) body colouration and presence of a mosaic-type patterning in the unpaired fins (vs. absence). The position of relatedness of the genus Belontia with respect to other anabantoids remains somewhat...

Moderate
Adult male from Penang state, Peninsular Malaysia; aggressive mood.

Betta imbellisCrescent Betta

Osphronemidae · Ladiges, 1975

Max length
60mm SL2.4in SL
Tank
45 × 30cm18 × 12in
Temp
20–28°C68–82°F
pH
5.0–7.5

B. imbellis is included in the Betta splendens complex of closely-related species within the genus, of which members share the following set of characters: head length short 22-31 % SL; often a brightly-coloured body; iris of the eye with iridescent green or blue patches; body elongate or slender; opercles parallel when head viewed dorsally; caudal-fin rays red or brown and contrasting with the iridescent interradial membranes; unpaired fins without an irides...

Moderate
Adult male specimen from the aquarium trade.

Betta kuehnei

Osphronemidae · Schindler & Schmidt, 2008

Max length
60mm SL2.4in SL
Tank
60 × 30cm24 × 12in
Temp
21–25°C70–77°F
pH
6.0–7.5

It can be told apart from other members of the B. pugnax group by the following characters: caudal fin rounded in both males and females; chin bar and second postorbital stripe absent; adult males possess intensive blue or bluish-green iridescent (blackish in preservation) colouration on the sides of the head and throat extending from the snout tip to posterior edge of opercle; possession of two central body stripes, the upper extending from the pec...

Moderate
Mature adult male individual.

Betta mahachaiensis

Osphronemidae · Kowasupat, Panijpan, Ruenwongsa & Sriwattanarothai, 2012

Max length
60mm SL2.4in SL
Tank
45 × 30cm18 × 12in
Temp
22–28°C72–82°F
pH
7.0–8.5

Known only from a handful of localities in Bangkok, Samut Sakhon, Samut Songkhram and Samut Prakan provinces in central Thailand, all of which lie on the coast of the Gulf of Thailand. Most habitats are in close proximity to Bangkok, which continues to expand rapidly, are considered under extreme threat, and recent surveys have failed to confirm that the fish is still present in Samut Songkhram and Samut Prakan.

Moderate
Adult male; population unspecified.

Betta pallida

Osphronemidae · Schindler & Schmidt, 2004

Max length
40mm SL1.6in SL
Tank
60 × 30cm24 × 12in
Temp
22–27°C72–81°F
pH
5.5–7.0

Has been collected from a slowly-moving creek which ranged in depth from 20-50 cm. The water was clear and slightly-stained with tannins and the subtrate was covered by a layer of leaf litter. PH was 6.3, conductivity 82 µS/cm and water temperature 25.5°C. At another locality pH was 6.5, conductivity 69 µS/cm and water temperature 26.6 °C.

Moderate
Individual from Terengganu state, Peninsular Malaysia.

Betta pi

Osphronemidae · Tan, 1998

Max length
90mm SL3.5in SL
Tank
90 × 30cm36 × 12in
Temp
22–28°C72–82°F
pH
4.0–6.5

B. pi is included in the Betta waseri group of closely-related species within the genus, an assemblage within which members share the following combination of characters: base body colouration clay yellow; opercle scales iridescent gold in mature males of all species except B. tomi; throat with black markings which join with black lower jaw in some species; no chin bar.

Moderate
Adult female specimen.

Betta prima

Osphronemidae · Kottelat, 1994

Max length
50mm SL2.0in SL
Tank
60 × 30cm24 × 12in
Temp
23–27°C73–81°F
pH
4.0–7.0

It can be told apart from other members of the B. pugnax group by the following characters: second postorbital stripe on opercle complete; no transverse bars in caudal-fin; 20-22 predorsal scales; preanal length 50.6-54.8 % SL. Not all authors consider it a member of this group, however, with some placing it in the B. picta complex, e.g., Schindler and Schmidt (2006). The genus is th...

Moderate
Adult male specimen from Vietnam; aggressive mood.

Betta siamorientalis

Osphronemidae · Kowasupat, Panijpan, Ruenwongsa & Jeenthong, 2012

Max length
33mm SL1.3in SL
Tank
45 × 30cm18 × 12in
Temp
22–28°C72–82°F
pH
5.5–7.5

This species was considered a colour form of the closely-related B. imbellis and commonly-referred to as 'black imbellis' prior to description due to its blackish opercle and body. It's also previously been confused with B. splendens due to the colour of the vertical opercular bars which tend to be reddish (but may also be pale red, greenish-silvery, plain silvery or without colour in some populations), but DNA analysis has demonstrated it...

Moderate
Adult male specimen.

Betta simplex

Osphronemidae · Kottelat, 1994

Max length
60mm SL2.4in SL
Tank
60 × 30cm24 × 12in
Temp
20–28°C68–82°F
pH
7.0–8.0

B. simplex is included in the Betta picta group/complex of closely-related species within the genus, an assemblage comprising species with the following shared characters: unpaired fins rounded (anal-fin sometimes tapering to a blunt point); anal-fin rays I-III, 18-24; dark marginal band on anal and caudal fins, more pronounced in mature males; presence of pre-orbital and post-orbital stripes; presence of chin bar on throat; iridescent green, gold, or blue scales on opercle.

Moderate
Adult male specimen from the Malaysian aquarium trade.

Betta smaragdinaEmerald Betta

Osphronemidae · Ladiges, 1972

Max length
60mm SL2.4in SL
Tank
45 × 30cm18 × 12in
Temp
22–28°C72–82°F
pH
5.5–7.5

This species is included in the Betta splendens complex of closely-related species within the genus, of which members share the following set of characters: head length short 22-31 % SL; often a brightly-coloured body; iris of the eye with iridescent green or blue patches; body elongate or slender; opercles parallel when head viewed dorsally; caudal-fin rays red or brown and contrasting with the iridescent interradial membranes; unpaired fins without an iridescent margin; opercle with red or blue vertical bars in males; dorsal-fin rays 0-II, 7-9; anal-fin rays II-V, 21-26.

Moderate
Wild-collected adult male specimen.

Betta splendensSiamese Fighting Fish

Osphronemidae · Regan, 1910

Max length
70mm SL2.8in SL
Tank
45 × 30cm18 × 12in
Temp
22–30°C72–86°F
pH
6.0–8.0

This species' common name is derived from the tradition of keeping the fish in order to fight against each other in organised 'bouts' upon which participants and onlookers place wagers. It has been extensively line-bred for vigour, strength, and the ornamental trade, and hybridised with the congeners B. imbellis, B. smaragdina, and B. mahachaiensis.

Moderate
Adult male from the UK aquarium trade.

Boraras maculatusDwarf Rasbora

Cyprinidae · Duncker, 1904

Max length
25mm SL1.0in SL
Tank
45 × 30cm18 × 12in
Temp
20–28°C68–82°F
pH
4.0–6.5

Within the genus Boraras this species is most similar to B. naevus, though in the latter the red body colouration does not extend into the head. The two also differ in the following characters: anteriormost lateral blotch of comparable size in both sexes in B. maculatus vs. significantly larger in male than female B. naevus; 9-10 + 9 principal caudal-fin rays vs. 9 + 8; 26-29 lateral scales vs. 24-26; i.6.i. pelvic-fin rays vs. i.5.i.

Easy
B. micros is the smallest member of the genus.

Boraras micros

Cyprinidae · Kottelat & Vidthayanon, 1993

Max length
13mm SL0.5in SL
Tank
45 × 30cm18 × 12in
Temp
20–28°C68–82°F
pH
6.0–7.0

Bung Khong Long is a lake and confirmed locality in Nong Khai province, Thailand. Aquatic plant species in the lake and surrounding floodplain include Hydrilla verticillata, Ceratophyllum dermersum, Chara zeylanica and Blyxa echinosperma. Salvinia cucullata is found floating on the surface and emergent plants comprise Eleocharis dulcis, Nelumbo nucifera, Lepironia articulata and Nymphaea lotus.

Easy
This species has been traded as B. sp. 'micros' or 'red micros', B. sp. 'Petch Noi', B. sp. 'Thailand', B. sp. 'south Thailand' or 'strawberry rasbora'

Boraras naevus

Cyprinidae · Conway & Kottelat, 2011

Max length
20mm SL0.8in SL
Tank
45 × 30cm18 × 12in
Temp
20–28°C68–82°F
pH
5.0–7.0

Known only from southern (peninsular) Thailand with the type series originating from a swamp some 83 km north of Surat Thani city, Surat Thani province. It's been recorded at additional locations, all within the lower Tapi river drainage on the Gulf of Thailand slope of the Malay Peninsula. In the description Conway and Kottelat (2011) report the occurence of a similar-looking, possibly conspecific fish on the Andaman Sea side of the Peninsula, close to Trang province.

Easy
Male specimen from the UK aquarium trade.

Boraras urophthalmoides

Cyprinidae · Kottelat, 1991

Max length
16mm SL0.6in SL
Tank
45 × 30cm18 × 12in
Temp
20–28°C68–82°F
pH
6.0–7.0

The anatomical structure of miniaturised cyprinids can vary greatly, and there are two principle 'groupings' with some species possessing intermediate features to some degree. The first contains those fishes which though small are essentially proportionally dwarfed versions of their larger relatives, e.g., Barboides, Microdevario, Microrasbora, Horadandia, Boraras, Sawbwa, Sundadanio, Danio, Laubuca and Rasbora. The other includes those in which anatom...

Easy
Individual with typical subadult patterning.

Botia kubotaiPolka-Dot Loach

Botiidae · Kottelat, 2004

Max length
150mm SL6in SL
Tank
120 × 45cm48 × 18in
Temp
22–28°C72–82°F
pH
6.0–7.5

Appears to be endemic to headwaters of the Salween River basin around the border between Myanmar and Thailand. The type specimens were collected from the Megathat Chaung (Megathat stream) in the upper Ataran (known as the Kasat in Thai) River basin, Kayin/Karen State, Myanmar and another population was later discovered in the Hanthayaw River (Suriya in Thai), Tak Province, Thailand.

Easy
Wild-collected specimen from eastern Thailand.

Brachydanio albolineataPearl 'Danio'

Cyprinidae · Blyth, 1860

Max length
55mm SL2.2in SL
Tank
90 × 30cm36 × 12in
Temp
16–25°C61–77°F
pH
6.0–8.0

Doubts remain whether B. albolineata is representative of a single species or a group of similarly-patterned, closely-related fish, and the form from Chantaburi province in eastern Thailand was revalidated as B. pulchra (formerly Danio pulcher Smith, 1931) by Kottelat (2013). The status of the currently invalid Danio tweedei (Brittan, 1955) from Kedah state, northern Peninsular Malaysia may also be in question, since fish from that area are clearly...

Easy
Male individual from northern Thailand.

Brachydanio roseaRosy 'Danio'

Cyprinidae · Fang & Kottelat, 2000

Max length
55mm SL2.2in SL
Tank
90 × 30cm36 × 12in
Temp
18–25°C64–77°F
pH
6.0–7.5

B. rosea is a relatively recent addition to the aquarium trade but has proved very popular since it's colourful, hardy and usually quite cheap making it ideal for beginners. It's sometimes sold as 'purple passion danio'. It's very similar to B. albolineata sensu stricto but differs in several characters, notably the relatively slimmer body, shorter rostral barbels and lack of...

Easy
Wild individual collected near Siam Reap, northwestern Cambodia.

Brachygobius mekongensisMekong Bumblebee Goby

Gobiidae · Larson & Vidthayanon, 2000

Max length
18mm SL0.7in SL
Tank
45 × 30cm18 × 12in
Temp
22–28°C72–82°F
pH
5.5–7.5

Apparently restricted to slow-moving or standing freshwater habitats such as marshes, temporal swamps and floodplains where aquatic vegetation and submerged grasses proliferate. One locality consisted of undisturbed marshland with lightly tannin-stained water and dense growth of Vallisneria spp.

Moderate
Wild specimen collected close to the type locality in Johor state, southern Peninsular Malaysia. Note that the anterior base of the dorsal-fin is unpigmented (see 'Notes').

Brachygobius xanthomelas

Gobiidae · Herre, 1937

Max length
20mm SL0.8in SL
Tank
45 × 30cm18 × 12in
Temp
22–28°C72–82°F
pH
7.0–8.5

Type locality is '55 miles north of Singapore, freshwater ditches, Mawai District, Johore, Malaysia', and this species has been recorded throughout much of Peninsular Malaysia and southern Thailand. Records from Borneo and Singapore appear to be in error although it may have been extirpated from the latter but as with most members of the genus a degree of confusion surrounds its identity (see 'Notes').

Moderate
Wild male specimen from Thailand.

Brevibora dorsiocellataEyespot Rasbora

Cyprinidae · Duncker, 1904

Max length
35mm SL1.4in SL
Tank
45 × 30cm18 × 12in
Temp
20–25°C68–77°F
pH
5.0–7.5

B. dorsiocellata is sometimes traded as 'green-eyed', 'emerald-eyed' or 'hi-spot' rasbora. There appear to exist several geographical forms of the species at least two of which have been seen in the trade. The most common is the rather plain-coloured fish that is produced commercially in large numbers and has gained popularity due to the bright green/blue reflective patch in the lower part of the eye.

Easy
Live individual from Thailand.

Butis amboinensisOlive Flathead Gudgeon

Eleotridae · Bleeker, 1853

Max length
140mm SL6in SL
Tank
75 × 30cm30 × 12in
Temp
22–28°C72–82°F
pH
7.0–8.5

This species is not traded for aquaria but is occasionally exported as bycatch among shipments of other species. It differs from congeners in that the outermost row of teeth are not enlarged plus the interorbital space and cheek below eye are not scaled. Butis spp. are largely nocturnal ambush predators with cryptic...

Easy
Specimen from Thailand.

Butis butisCrazy Fish

Eleotridae · Hamilton, 1822

Max length
120mm SL5in SL
Tank
75 × 30cm30 × 12in
Temp
22–27°C72–81°F
pH
7.0–8.5

Butis spp. are largely nocturnal ambush predators with cryptic patterning to help them blend in with their surroundings. They can also lighten and darken their body colouration to an extent, have a habit of aligning themselves with solid surfaces whether horizontal, vertical, or inverted, and often swim in an upside-down position. The genus is usually included in the family Eleotridae of which members are often referred to...

Easy
Adult male from the German aquarium trade.

Carinotetraodon lortetiRedeye Puffer

Tetraodontidae · Tirant, 1885

Max length
60mm SL2.4in SL
Tank
60 × 30cm24 × 12in
Temp
20–28°C68–82°F
pH
5.0–7.5

Known from the lower Mekong basin in Thailand, Vietnam, and Cambodia, the Chao Phraya watershed in central Thailand, and may occur in smaller river systems between. Type locality is 'Thu-dâu-môt, Vietnam'.

Moderate
Well-conditioned adult specimen.

Chagunius baileyi

Cyprinidae · Rainboth, 1986

Max length
200mm SL8in SL
Tank
180 × 60cm72 × 24in
Temp
18–25°C64–77°F
pH
6.0–7.5

There are currently three species which look almost identical and are most easily separated by collection details since their ranges do not overlap in nature; C. chagunio is endemic to the Ganges and Brahmaputra drainages and C. nicholsi to the Ayeyarwady/Irrawaddy.

Moderate
Specimen from the German aquarium trade imported as C. gachua 'Assam'.

Channa gachuaDwarf Snakehead

Channidae · Hamilton, 1822

Max length
200mm SL8in SL
Tank
120 × 45cm48 × 18in
Temp
18–28°C64–82°F
pH
5.0–8.0

Generally considered to have an enormous natural range extending from Iran to Taiwan and Bali, with records existing from Iran, Iraq, Afghanistan, Pakistan, Nepal, India, Sri Lanka, Bangladesh, Bhutan, China, Myanmar, Thailand, Laos, Cambodia, Vietnam, Malaysia, Indonesia, and Singapore. However there exists significant evidence to suggest that C. gachua as currently understood represents a complex of similar-looking species, and a taxonomic review of the group is clearly required.

Easy
Channa lucius NP

Channa luciusForest Snakehead

Channidae · Cuvier, 1831

Max length
400mm SL16in SL
Tank
150 × 60cm60 × 24in
Temp
20–30°C68–86°F
pH
5.0–7.5

Prefers a dimly-lit aquarium with plenty of cover in the form of live plants, driftwood branches, terracotta pipes, plant pots, etc., arranged to form a network of nooks, crannies, and shaded spots. Surface vegetation such as Ceratopteris spp. is also appreciated and makes the fish less inclined to conceal themselves.

Moderate
Subadult from the German aquarium trade.

Channa melasomaBlack Snakehead

Channidae · Bleeker, 1851

Max length
300mm SL12in SL
Tank
120 × 45cm48 × 18in
Temp
22–32°C72–90°F
pH
4.0–7.0

This species can be told apart from the similar-looking congener C. baramensis (once considered synonymous with C. melasoma) by absence (vs. presence) of a black spot in the centre of numerous body scales and absence (vs. presence in specimens larger than 120 mm SL) of a barred caudal-fin pattern.

Moderate
Adult individual measuring approximately 150-170 mm TL.

Channa sp. 'fire and ice'

Channidae · authority not recorded

Max length
150mm SL6in SL
Tank
120 × 30cm48 × 12in
Temp
22–28°C72–82°F
pH
6.0–7.5

This unidentified species first appeared in the aquarium trade during 2009. It's easily told apart from similar-looking congeners by the patches of vivid red pigmentation surrounding the eye and sides of the mouth plus the thick, reddish, marginal band in the caudal-fin.

Moderate
Adult specimen from Thailand.

Crossocheilus atrilimesSiamese Algae Eater

Cyprinidae · Kottelat, 2000

Max length
75mm SL3.0in SL
Tank
120 × 30cm48 × 12in
Temp
20–26°C68–79°F
pH
6.0–7.5

This species is among a handful of near-identical congeners that are traded as 'Siamese algae-eater' (often abbreviated to 'SAE'), 'Siamese flying fox' and 'Crossocheilus siamensis'. The latter name is not valid, however, and is a synonym of Epalzeorhynchos siamensis which is itself a synonym of Crossocheilus oblongus, a species described from Java. C. oblongus is currently accepted to...

Easy
Crossocheilus langei.

Crossocheilus langeiSiamese Algae Eater

Cyprinidae · Bleeker, 1860

Max length
150mm SL6in SL
Tank
150 × 45cm60 × 18in
Temp
20–26°C68–79°F
pH
6.0–7.5

C. oblongus is another name widely misused in the trade but that species has seemingly never been exported and was described as a blueish fish with yellow fins. It's native to streams of Gunung Salak mountain in Bogor Regency, West Java, Indonesia where collecting of ornamental fishes is almost non-existent. Other species of laterally-striped Crossocheilus also exist and may be available from time-to-time but are more easily told apart from the group described above.

Easy
Subadult specimen from the UK aquarium trade.

Crossocheilus reticulatus

Cyprinidae · Fowler, 1934

Max length
170mm SL7in SL
Tank
180 × 45cm72 × 18in
Temp
16–24°C61–75°F
pH
6.0–7.5

While some laterally-striped members of the genus look very similar to one another the combination of silvery body, dark-edged scales and dark caudal peduncle blotch set C. reticulatus uniquely apart. The names Crossocheilus tchangi, Epalzeorhynchos coatesi and E. stigmaeus are all now considered synonyms of the species but were erected because the fish vary, most often in minor aspects of patt...

Easy
Adult specimen from Thailand in the aquarium.

Cyclocheilichthys apogonBeardless Barb

Cyprinidae · Valenciennes, 1842

Max length
180mm SL7in SL
Tank
180 × 45cm72 × 18in
Temp
20–27°C68–81°F
pH
5.5–8.0

In the aquarium trade this species may also be seen on sale as 'skinhead barb'. As with others in the genus little has been written regarding its captive care but it makes a peaceful and unusual addition to larger aquaria. The best way of obtaining it may be to keep an eye on shipments of wild fishes from Indochina and the Greater Sunda Islands as it's rarely imported in large numbers and most often arrives as bycatch.

Moderate
Adult individual from Thailand.

Cyclocheilichthys armatus

Cyprinidae · Valenciennes, 1842

Max length
230mm SL9in SL
Tank
180 × 60cm72 × 24in
Temp
20–26°C68–79°F
pH
6.0–8.0

It can be distinguished from congeners by possessing one or two pairs of barbels, a black blotch at the base of the caudal-fin, and rows of dark spots along the lateral scale rows. Members of Cyclocheilichthys are characterised by possessing a serrated dorsal fin spine, 9 branched pelvic fin rays, a conical snout, small, subterminal...

Moderate
Young specimen of Cyclocheilichthys heteronema.

Cyclocheilichthys heteronema

Cyprinidae · Bleeker, 1854

Max length
120mm SL5in SL
Tank
120 × 45cm48 × 18in
Temp
21–26°C70–79°F
pH
6.0–7.5

This species is currently understood to have a considerable natural range extending eastwards from Myanmar via Thailand, Laos, Cambodia as far as Vietnam and to the south through Peninsular Malaysia and into the Greater Sunda Islands of Borneo and Sumatra. It thus occurs in the Mekong, Mae Klong and Chao Phraya drainages as well as a host of other river basins, lakes and reservoirs including the Tonlé Sap river...

Easy
Wild-collected adult individual.

Cyclocheilichthys lagleri

Cyprinidae · Sontirat, 1985

Max length
200mm SL8in SL
Tank
180 × 60cm72 × 24in
Temp
20–26°C68–79°F
pH
6.0–8.0

As with others in the genus little has been written regarding captive care of this species, but it makes a peaceful and unusual addition to larger aquaria. The best way of obtaining it may be to keep an eye on shipments of wild fishes from Indochina. It can be distinguished from congeners by possessing 20 circumpeduncular scales and lacking barbels entirely.

Moderate
Wild individual from Thailand.

Cyclocheilichthys repasson

Cyprinidae · Bleeker, 1853

Max length
280mm SL11in SL
Tank
180 × 45cm72 × 18in
Temp
20–26°C68–79°F
pH
5.0–8.0

An ideal resident of the larger, well-furnished community set-up though it might upset slow-moving or timid companions simply by its size. There are plenty of suitable tankmates including many cyprinids, loaches, cichlids, catfish and characins, but as always when selecting a compatible community of fish proper research is essential. A community based around one of its native countries or river basins...

Moderate
Adult individual from the Chao Phraya River, central Thailand.

Datnioides polotaSilver Tiger Perch

Datnioididae · Hamilton, 1822

Max length
300mm SL12in SL
Tank
180 × 60cm72 × 24in
Temp
20–28°C68–82°F
pH
7.5–9.0

D. polota is sometimes referred to as D. quadrifasciatus (Sevastianov, 1809) but the original name of the latter, Chaetodon quadrifasciatus Sevastianov, 1809, is a junior primary homonym of the older Chaetodon quadrifasciatus Bloch & Schneider 1801, thus Coius polota Hamilton, 1822 takes precedence.

Moderate
Subadult individual.

Datnioides undecimradiatusMekong Tiger Perch

Datnioididae · Roberts & Kottelat, 1994

Max length
300mm SL12in SL
Tank
180 × 60cm72 × 24in
Temp
20–28°C68–82°F
pH
5.5–7.5

An efficient, largely piscivorous, predator with highly protrusible mouthparts. In the aquarium, juveniles can be offered chironomid larvae (bloodworm), small earthworms, chopped prawn, and suchlike, while adults will accept strips of fish flesh, whole prawns, mussels, live river shrimp, larger earthworms, etc. Older individuals do not require feeding on a daily basis, with 2-3 times per week sufficient.

Moderate
Wild-collected adult from southern Thailand.

Desmopuntius johorensisStriped Barb

Cyprinidae · Duncker, 1904

Max length
100mm SL3.9in SL
Tank
120 × 45cm48 × 18in
Temp
20–25°C68–77°F
pH
5.0–7.0

D. johorensis can be distinguished by the following combination of characters: 5-6 dark, lateral stripes on body in specimens larger than 40 mm; stripes immediately above and below the central stripe (stripes '+1' and '-1', respectively) located on scale rows +2 and -2, not touching dorsal and ventral midlines (except in some small specimens from Peninsular Malaysia); stripes broad, typically between 0.5-1 scale rows deep...

Easy
D. acrostomus first appeared in the trade in early 2011.

Devario acrostomus

Cyprinidae · Fang & Kottelat, 1999

Max length
80mm SL3.1in SL
Tank
120 × 45cm48 × 18in
Temp
23–26°C73–79°F
pH
6.0–7.0

The type series was collected during the dry season from localities with varying gradient both within the Nam Leuk mainstream and smaller tributaries. In the tributaries the fish were found congregating in pools some of which were isolated on steep slopes. All habitats above Tad Leuk falls were characterised by clear to very clear water under forest cover while below the falls they were dominated by exposed basalt slabs with some underground water channels.

Moderate
Wild male specimen from Xishuangbanna Dai autonomous prefecture, Yunnan Province, southwestern China.

Devario chrysotaeniatus

Cyprinidae · Chu, 1981

Max length
75mm SL3.0in SL
Tank
120 × 30cm48 × 12in
Temp
23–26°C73–79°F
pH
6.0–7.0

This species is poorly known and first appeared in the hobby during 2005 but has rarely been seen since, probably because its natural waters lie outside the range of most commercial collectors. It can be distinguished by a combination of characters including: lateral line complete; infraorbital process absent; two pairs of short barbels; 8-9 branched dorsal fin rays; 12-13 branched anal fin rays; P stripe originating above pelvic fin and extending to en...

Moderate
Adult specimen of D. laoensis in normal colouration.

Devario laoensis

Cyprinidae · Pellegrin & Fang, 1940

Max length
65mm SL2.6in SL
Tank
90 × 30cm36 × 12in
Temp
23–26°C73–79°F
pH
6.0–7.5

It can be further distinguished from other species in the genus by colour pattern consisting of a dark, horizontal P stripe originating around mid-body, where it's relatively faint, this becoming thicker and darker in the posterior portion of the body and terminating at the base of the caudal-fin. Among congeners it's most similar to D. chrysotaeniatus but that species lacks the infraorbital process, has three rows of pharyngeal teeth and the P stripe extends to the end of the caudal-fin rays.

Moderate
Subadult from Perlis state, Peninsular Malaysia.

Devario reginaQueen 'Danio'

Cyprinidae · Fowler, 1934

Max length
80mm SL3.1in SL
Tank
120 × 45cm48 × 18in
Temp
20–26°C68–79°F
pH
5.5–7.5

Probably restricted to western and southern Thailand and northern Peninsular Malaysia plus some small surrounding islands. In Thailand records exist from Surat Thani (Ko Samui island), Nakhon Si Thammarat, Ranong, Trang, Phuket, Ratchaburi, Kanchanaburi, and Mae Hong Son provinces while in Peninsular Malaysia it's been collected from Perak and Kedah states, including th...

Easy
Specimen from Thailand.

Discherodontus ashmeadi

Cyprinidae · Fowler, 1937

Max length
135mm SL5in SL
Tank
120 × 45cm48 × 18in
Temp
23–26°C73–79°F
pH
6.0–7.5

D. ashmeadi is the type species and exhibits differences in dental morphology compared with other members of the genus. It can also be told apart from D. halei by the red/pink (vs. orange) colouration in the dorsal and anal fins and serrated (vs. smooth) dorsal spine. D. schroederi is also similar-looking but as it matures the prominent dark dorsal blotch fades to a thin dark distal band whereas in D. ashmeadi it is retained throughout life.

Moderate
Specimens from Thailand.

Discherodontus halei

Cyprinidae · Duncker, 1904

Max length
100mm SL3.9in SL
Tank
120 × 45cm48 × 18in
Temp
21–26°C70–79°F
pH
6.0–7.5

Appears to have a disjunct range with records from Pahang state in central Peninsular Malaysia, plus the Mae Klong and Chao Phraya river systems in Thailand, but it has not been recorded in Peninsular Thailand. Type locality is 'Pahang River, Kuala Tembeling, eastern slope of Sangka Dua Pass, Malaysia, elevation about 2000 feet'.

Moderate
Discherodontus schroederi.

Discherodontus schroederi

Cyprinidae · Smith, 1945

Max length
100mm SL3.9in SL
Tank
120 × 30cm48 × 12in
Temp
23–26°C73–79°F
pH
6.0–7.5

It's also been collected in more open areas but wherever it is found the substrate is composed of boulders, smaller stones, sand and/or gravel along with decomposing plant material. From images we've seen typical habitats are composed of short sections of rocky rapids interspersed by deeper pools with exposed bedrock. Rainboth describes how he collected a large group of...

Moderate
Probable adult male of E. octozona.

Eirmotus octozona

Cyprinidae · Schultz, 1959

Max length
36mm SL1.4in SL
Tank
60 × 30cm24 × 12in
Temp
22–26°C72–79°F
pH
5.0–7.0

E. octozona can be told apart from congeners by the following combination of characters: bar 1 present; presence of a large and distinct black mark anterior to anus, visible in lateral and ventral views; simple dorsal-fin rays black, sometimes extending onto first branched ray; other rays hyaline or with diffused chromatophores on last dorsal-fin ray, adjacent to upper extremity of bar 6; 25-31 serrae on last simple dorsal-fin ray; uppermost ray of pectoral-fin with faint black margin; width of bar 5 equal to 1-1½ lat...

Moderate
Subadult individual.

Epalzeorhynchos bicolorRed-Tailed Black Shark

Cyprinidae · Smith, 1931

Max length
125mm SL5in SL
Tank
120 × 45cm48 × 18in
Temp
20–26°C68–79°F
pH
6.0–8.0

Most members of Epalzeorhynchos were formerly regarded as Labeo spp. and are thus referred to as such in older literature. According to Rainboth (1996) they're characterised by absence of a dorsal spine, possession of 10-13 branched dorsal fin rays, a thin membrane connecting the upper and lower lips and rigid, freely moveable rostral lobes. Epalzeorhynchos itself has undergone some quite recent changes with a handful of species hav...

Easy
Subadult specimen from the aquarium trade.

Epalzeorhynchos frenatumRainbow Shark

Cyprinidae · Fowler, 1934

Max length
150mm SL6in SL
Tank
120 × 45cm48 × 18in
Temp
20–26°C68–79°F
pH
6.5–8.0

The ornamental albino variant is widely-available and has become extremely popular in the hobby and there is a commercially-produced anerythristic (lacking red pigment) mutation that has pale yellowish fins and has sometimes been misidentified as E. munense. Also worthy of note is that the specific name is sometimes misspelled 'frenatus'. Most members of Epalzeorhynchos were formerly regarded as Labeo spp. and are thus referred to as such in older literature. According to Rainboth (1996) they're characterised by absence of a dorsal spine...

Easy
Subadult specimen from southern Thailand.

Epalzeorhynchos kalopterumFlying Fox

Cyprinidae · Bleeker, 1850

Max length
160mm SL6in SL
Tank
120 × 45cm48 × 18in
Temp
20–26°C68–79°F
pH
6.0–7.5

Confusion with similar-looking fishes from other genera, such as Garra cambodgiensis, laterally-striped Crossocheilus spp. or Gyrinocheilus aymonieri is not uncommon, and are largely attributable to the use of trade names such as 'false flying fox' or 'Siamese flying fox'. When compared with the other species E. kalopterus exhibits several unique characters but perhaps the simplest way to identify it is by the characteristic white-edged, red and black coloured fins and the presence of two pairs of barbels.

Easy
Young specimen of Epalzeorhynchos munense. Note the combination of red pectoral and caudal fins which distinguish this species from E. bicolor and E. frenatum.

Epalzeorhynchos munense

Cyprinidae · Smith, 1934

Max length
120mm SL5in SL
Tank
120 × 45cm48 × 18in
Temp
20–26°C68–79°F
pH
6.5–7.5

This species does not appear to be in the aquarium hobby at time of writing though it may have been in the past, when exports of wild Epalzeorhynchos spp. still took place. Most members of the genus were formerly regarded as Labeo spp. and are thus referred to as such in older literature. According to Rainboth (1996) they're characterised by absence of a dorsal spine, possession of 10-13 branched dorsal fin rays, a thin membrane...

Moderate
Individual collected from the Tonlé Sap lake, Cambodia.

Esomus longimanusMekong Flying Barb

Cyprinidae · Lunel, 1881

Max length
80mm SL3.1in SL
Tank
120 × 30cm48 × 12in
Temp
20–28°C68–82°F
pH
6.0–8.0

Known from the Mekong river basin in Thailand, Laos, Cambodia, and Vietnam, the Tonlé Sap river and lake system in Cambodia, and smaller, coastal drainages in southeast Thailand. Records from Peninsular Malaysia are likely to refer to other species. Type locality is given simply as 'Cambodia'.

Easy
Specimen from Thailand.

Esomus metallicusStriped Flying Barb

Cyprinidae · Ahl, 1923

Max length
75mm SL3.0in SL
Tank
120 × 30cm48 × 12in
Temp
20–26°C68–79°F
pH
6.0–7.0

There currently exist a dozen described Esomus spp. alhough few are seen in the aquarium trade and none are especially popular. Most are commonplace in their native countries and also quite plainly-patterned so generally overlooked by collectors. Their most common use in some areas is actually as a feeder fish in the aquaculture of larger species. They're characterised by greatly-enlarged pectoral fins and two pairs of barbels, of which the maxillary pair are extremely long and usually reach the pectoral fins.

Moderate
Juvenile specimen from Thailand.

Folifer brevifilis

Cyprinidae · Peters, 1881

Max length
300mm SL12in SL
Tank
240 × 60cm96 × 24in
Temp
20–26°C68–79°F
pH
6.0–8.0

This species is widely-distributed in the Mekong river system in Thailand, Laos, and Vietnam, Salween and Ayeyarwaddy rivers in southern China, Myanmar, and Thailand, plus various smaller basins in Vietnam and China. It has also been recorded from the islands of Hainan and Hong Kong. Type locality is given as 'China: sent from Hong Kong'.

Moderate
Specimen in its natural habitat, Chanthaburi province, eastern Thailand.

Garra cambodgiensisFalse SAE

Cyprinidae · Tirant, 1883

Max length
150mm SL6in SL
Tank
120 × 45cm48 × 18in
Temp
20–27°C68–81°F
pH
6.0–7.5

Also known by the vernacular names ''black band garra', 'stone-lapping minnow' or 'false flying fox' and continues to be traded as Garra taeniata, an invalid name synonymous with G. cambodgiensis. It is often confused with those laterally-striped members of the genus Crossocheilus sold as 'Siamese algae eater' or 'Siamese flying fox', but in those species the dark lateral body stripe continues into the caudal-fin whereas in G. cambodgiensis it terminates...

Easy
Specimen from Thailand.

Garra fasciacauda

Cyprinidae · Fowler, 1937

Max length
110mm SL4in SL
Tank
120 × 45cm48 × 18in
Temp
20–26°C68–79°F
pH
6.0–8.0

Native to the Mekong river system in Thailand, Laos, Vietnam, and Cambodia, including the Tonlé Sap basin. Type locality is 'Kemarat, Thailand', which corresponds to the Mekoong River in Khemmarat district, Ubon Ratchathani province, northeastern Thailand.

Easy
Putative male individual.

Garra sp. 'redtail'Burmese Red-tailed Garra

Cyprinidae · authority not recorded

Max length
75mm SL3.0in SL
Tank
120 × 30cm48 × 12in
Temp
20–27°C68–81°F
pH
6.0–7.5

A putatively undescribed species often imported and sold as G. sp. 'burmanicus'. It first appeared in the trade during 2005 and has since been available on a sporadic basis, usually with a relatively high price tag. As well as its unique colour pattern, a primary diagnostic character is the presence of a proboscis-like rostral process between the eyes.

Easy
This species is not a true freshwater fish and should be maintained in brackish conditions.

Gymnothorax tile'Freshwater' Moray Eel

Muraenidae · Hamilton, 1822

Max length
600mm SL24in SL
Tank
120 × 60cm48 × 24in
Temp
20–28°C68–82°F
pH
7.5–9.0

Gymnothorax tile

Moderate
Wild-collected subadult specimen from Thailand.

Gyrinocheilus aymonieriSucking 'Loach'

Gyrinocheilidae · Tirant, 1883

Max length
280mm SL11in SL
Tank
150 × 45cm60 × 18in
Temp
22–26°C72–79°F
pH
6.0–8.0

This species is among the most well-known fishes in the aquarium trade but juveniles are typically being offered for sale with little to no information regarding temperament, eventual size, and potential age in excess of 15 years. Wild examples are not currently traded, with all of those seen on sale produced on a commercial basis.

Moderate
Subadult specimen.

Hampala disparSpotted Hampala Barb

Cyprinidae · Smith, 1934

Max length
350mm SL14in SL
Tank
240 × 60cm96 × 24in
Temp
20–25°C68–77°F
pH
6.0–8.0

The genus currently contains seven species of which H. macrolepidota and, to a lesser extent, H. dispar are the only ones seen with any regularity in the aquarium trade. As well as having the widest distribution H. macrolepidota is also the largest member of the group. All representatives can appear superficially similar at first glance, the exception being H. lopezi which is endemic to a single island in The Philippines and displays a unique lateral band-like marking on the flanks.

Moderate
Subadult specimen in the aquarium.

Hampala salweenensis

Cyprinidae · Doi & Taki, 1994

Max length
201mm SL8in SL
Tank
240 × 60cm96 × 24in
Temp
20–26°C68–79°F
pH
6.0–8.0

This species is poorly-known in the aquarium hobby and may have never been maintained outside its native countries. It can be distinguished from congeners by the following combination of characters: 26-27 lateral line scales; two roundish, dark blotches on each flank, one beneath dorsal-fin origin and above the lateral line, the other on the caudal peduncle and passing thro...

Moderate
The natural form of this species is rarely-seen in aquaria. This one is from Thailand.

Helostoma temminkiiKissing Gourami

Helostomatidae · Cuvier, 1829

Max length
250mm SL10in SL
Tank
150 × 45cm60 × 18in
Temp
22–30°C72–86°F
pH
6.0–8.0

The pinkish-white form of this species is among the most widely-traded aquarium fishes in the world but does not occur naturally and is in fact a leucistic variant bred specifically for ornamental purposes. The 'short-bodied' or 'balloon' variety also continues to be fashionable but under no circumstances do we recommend the purchase of these intentionally disfigured animals which tend to have much shorter life spans than the naturally-shaped fish. There also exists a less-po...

Moderate
This species may not yert have appeared in the aquarium hobby.

Hemimyzon nanensis

Balitoridae · Doi & Kottelat, 1998

Max length
57mm SL2.2in SL
Tank
90 × 30cm36 × 12in
Temp
16–22°C61–72°F
pH
6.0–8.0

Most importantly the water must be clean and well-oxygenated so we suggest the use of an over-sized filter as a minimum requirement. Turnover should ideally be 10-15 times per hour so additional powerheads, airstones, etc. should also be employed as necessary. Base substr...

Moderate
A typically-patterned specimen of H. bilineata.

Homaloptera bilineata

Balitoridae · Blyth, 1860

Max length
100mm SL3.9in SL
Tank
120 × 30cm48 × 12in
Temp
20–25.5°C68–78°F
pH
6.0–7.5

This rarely-traded species is a member of the H. ocellata 'group' of closely-related congeners, an assemblage which currently comprises H. ocellata, H. bilineata, H. confuzona, H. orthogoniata, H. ogilviei and H. parclitella. Following Tan and Ng (2005) these share possession of a colour pattern with reddish tints and dark brown head markings, elongate head, slightly compressed body, 61-77 lateral line scales and dorsal-fin origin placed in advance of pelvic-fin origin.

Moderate
Adult specimen from Thailand.

Homaloptera confuzona

Balitoridae · Kottelat, 2000

Max length
85mm SL3.3in SL
Tank
120 × 30cm48 × 12in
Temp
20–25.5°C68–78°F
pH
6.0–7.5

Most records pertain to the Mekong River basin downstream of the Khone waterfalls in Laos and Cambodia, but this species is also known from some smaller river drainages in southern Thailand, including parts of the Mae Klong system. Type locality is 'Khlong Fit at Ban Kraduk Chang, road 3157 from Trat to borai, about 2-3 kilometers after junction w...

Moderate
Specimen from southern Thailand.

Homaloptera ogilviei

Balitoridae · Alfred, 1967

Max length
50mm SL2.0in SL
Tank
60 × 30cm24 × 12in
Temp
20–25.5°C68–78°F
pH
6.0–7.5

The reason that the paired fins are orientated vertically, as opposed to horizontally in other members of the genus, is unclear but Roberts (1989) suggest it may be an adaptation to this species' ecology, in that it displays a preference for submerged vegetation or woody structures as opposed to rocky environments. They're certainly adapted for a rea...

Moderate
Adult specimen from southern Thailand.

Homaloptera parclitella

Balitoridae · Tan & Ng, 2005

Max length
80mm SL3.1in SL
Tank
120 × 30cm48 × 12in
Temp
20–25.5°C68–78°F
pH
6.0–7.5

The water at the type locality is described as 'clear and fast-flowing over a rocky substratum'. H. parclitella was observed in shallow water among the rocks, and sympatric species included Garra cambodgiensis, Neolissochilus soroides, Poropuntius smedleyi, 'Puntius' binotatus, Homaloptera nebulosa and Amblyceps mangois.

Moderate
·Wild specimen from the Salween watershed, Thailand.

Homalopteroides modestus

Balitoridae · Vinciguerra, 1890

Max length
44mm SL1.7in SL
Tank
60 × 30cm24 × 12in
Temp
18–25.5°C64–78°F
pH
6.0–7.5

Homalopteroides spp. are specialised micropredators feeding on small crustaceans, insect larvae and other invertebrates. In captivity some sinking dried foods may be accepted but regular meals of live or frozen Daphnia, Artemia, bloodworm, etc., are essential for the maintenance of good health.

Moderate
H. smithi is the most commonly-available member of the H. wassinki species group.

Homalopteroides smithi

Balitoridae · Hora, 1932

Max length
60mm SL2.4in SL
Tank
60 × 30cm24 × 12in
Temp
20–25.5°C68–78°F
pH
6.0–7.5

Described from close to the village of Ban Khiri Wong, Nakhon Si Thammarat Province, southern (peninsular) Thailand but since recorded throughout much of the country, including the Chao Phraya and Mekong river systems. It's also known from Peninsular Malaysia and parts of the Mekong basin in Laos, Cambodia and Vietnam. Rainboth (1996) considered it 'probably the commonest member of the genus in the Mekong' and in a 2008 study of balitorid habitats in centra...

Moderate
Adult individual.

Homalopteroides tweediei

Balitoridae · Herre, 1940

Max length
40mm SL1.6in SL
Tank
45 × 30cm18 × 12in
Temp
20–25.5°C68–78°F
pH
6.0–7.5

Described from Kota Tinggi district, Johor state, Peninsular Malaysia but since recorded throughout much of the country as well as parts of the the Mekong river system in Thailand, Laos, Cambodia and Vietnam plus the Kapuas and several other river basins in Kalimantan Barat (West Kalimantan) province, Indonesian Borneo. In the Kahang River, part of the Endau drainage in Jo...

Moderate
Individual from Thailand.

Hypsibarbus lagleri

Cyprinidae · Rainboth, 1996

Max length
350mm SL14in SL
Tank
240 × 60cm96 × 24in
Temp
20–26°C68–79°F
pH
6.0–8.0

This species is migratory on a seasonal basis; during the dry season it can be found in larger river channels, whereas during drier months it moves into smaller tributaries and flooded forests. Apparently displays a preference for rocky habitats and is not known to adapt to reservoirs or other artificial impoundments.

Moderate
Specimen from Thailand.

Hypsibarbus vernayi

Cyprinidae · Norman, 1925

Max length
216mm SL9in SL
Tank
240 × 60cm96 × 24in
Temp
20–26°C68–79°F
pH
6.0–8.0

It is very similar to H. wetmorei but can be told apart by possessing yellow (vs. orange to red in H. wetmorei) pectoral, pelvic, and anal fins. It thus appears likely that yellow-finned fish marketed as H. wetmorei or 'lemon fin barb' in the ornamental trade are actually H. vernayi, with both species available on a regular basis.

Moderate
Putative adult male individual in the aquarium.

Hypsibarbus wetmorei

Cyprinidae · Smith, 1931

Max length
250mm SL10in SL
Tank
240 × 60cm96 × 24in
Temp
20–26°C68–79°F
pH
6.0–8.0

H. wetmorei is distinguished from congeners by the following combination of characters: upper body reddish brown; robust body, not compressed; usually 4½ scale rows between lateral line and dorsal-fin origin; 8-12 rakers on first gill arch; 7-9 predorsal scales; 14 circumpeduncular scale rows; usually two scale rows separating vent and anal-fin; <29 lateral line scales; 9-14 serrations on the spinous dorsal-fin ray; distance between distal serrae on posterior margin of last unbranched dorsal-fin ray much greater than the width of their bases.

Moderate
Adult male specimen from the aquarium trade.

Indostomus crocodilus

Indostomidae · Britz & Kottelat, 1999

Max length
30mm SL1.2in SL
Tank
40 × 20cm16 × 8in
Temp
22–27°C72–81°F
pH
5.0–7.0

The type series was collected from a blackwater stream in Toh Daeng Peat swamp forest with the fish found in slow-moving or standing habitats among submerged shoreline roots and leaf litter. In the Tapi River floodplain it was collected from stagnant waters, one of which was an oxbow lake approximately 200 m long and 30 m across at its widest point, surrounded by 'freshwater scrub and swamp trees'. The substrate was composed of mud, woody structures including fallen twigs and branches, and decomposing plant material.

Moderate
Wild-collected individual.

'Inlecypris' maetaengensisFire Bar 'Danio'

Cyprinidae · Fang, 1997

Max length
50mm SL2.0in SL
Tank
75 × 30cm30 × 12in
Temp
20–26°C68–79°F
pH
6.0–8.0

A peaceful species suited to a well-chosen community aquarium. There are plenty of potential tankmates including many cyprinids, loaches, cichlids, catfishes and characins, although as always proper research is essential in order to avoid problems.

Easy
Wild specimen from Thailand.

Kryptopterus bicirrhis

Siluridae · Valenciennes, 1840

Max length
150mm SL6in SL
Tank
120 × 45cm48 × 18in
Temp
20–28°C68–82°F
pH
6.0–7.5

Generally peaceful though it may predate on smaller fishes and is somewhat timid so does not compete well with much larger, robust or otherwise boisterous species. Peaceful, comparably-sized cyprinids, loaches and other catfishes perhaps constitute the best options but be sure to research your choices thoroughly prior to purchase.

Moderate
This species has probably appeared in the trade under the name of its close relative K. cryptopterus.

Kryptopterus geminus

Siluridae · Ng, 2003

Max length
171mm SL7in SL
Tank
150 × 45cm60 × 18in
Temp
20–28°C68–82°F
pH
6.0–7.5

This species is likely to be traded for aquaria but probably misidentified as the very similar-looking K. cyrptopterus with which wild populations were formerly considered conspecific. These two are closely-related and can be distinguished from congeners by the dorsal profile lacking a nuchal concavity (vs. possessing a nuchal concavity) and possessing short maxillary barbels (extending to the pectoral-fin base vs. ext...

Moderate
Young adult specimen from Thailand.

Kryptopterus limpok

Siluridae · Bleeker, 1852

Max length
260mm SL10in SL
Tank
240 × 60cm96 × 24in
Temp
20–28°C68–82°F
pH
6.0–7.5

Type locality is 'Palembang, Sumatra, Indonesia', but this species is widely-distributed throughout much of Southeast Asia including major river systems in Thailand, Laos, Cambodia, Vietnam and Peninsular Malaysia plus the Greater Sunda Islands of Sumatra, Borneo and Java. It's been extensively recorded from the Mekong, Cha...

Moderate
Specimen from southern Thailand.

Kryptopterus macrocephalusStriped Glass Catfish

Siluridae · Bleeker, 1858

Max length
100mm SL3.9in SL
Tank
120 × 30cm48 × 12in
Temp
20–26°C68–79°F
pH
4.0–7.0

Has been recorded in fast-flowing environments but most commonly associated with peat swamp forests and associated blackwater streams. Many such habitats have suffered degradation of some kind but in unaltered cases the dense canopy of branches above means very little light penetrates the surface of such environments, and riparian vegetation also tends to grow thickly.

Moderate
This species was finally described in 2013 after years of misidentification.

Kryptopterus vitreolusGlass Catfish

Siluridae · Ng & Kottelat, 2013

Max length
65mm SL2.6in SL
Tank
90 × 30cm36 × 12in
Temp
20–26°C68–79°F
pH
4.0–7.0

This species has been available in the trade for decades during which time it's been widely misidentified as the valid congeners K. bicirrhis or, more recently, K. minor. Its identity was not resolved until early 2013 meaning you will find it under one of these two names in the majority of literature published prior to that date. Other trade names include 'Asia...

Easy
Specimen from Thailand.

Labiobarbus leptocheilus

Cyprinidae · Valenciennes, 1842

Max length
260mm SL10in SL
Tank
240 × 60cm96 × 24in
Temp
20–26°C68–79°F
pH
6.0–8.0

Different populations vary in appearance somewhat (see image of Salween specimen for example), and L. leptocheilus may turn out to represent a group of closely-related species rather than a single taxon. The population from the Cambodian Mekong has been considered to represent a distinct species, Labiobarbus lineatus, although that name is currently a synonym of L. leptocheilus following Kottelat (2013). It is widely used in the ornamental trade, however.

Easy
Specimen from the Singapore aquarium trade.

Laubuka caeruleostigmataFlying Minnow

Cyprinidae · Smith, 1931

Max length
70mm SL2.8in SL
Tank
120 × 30cm48 × 12in
Temp
20–26°C68–79°F
pH
6.0–8.0

This species is also known as 'leaping barb' and was once quite common in the ornamental trade but is now seldom seen. It can be distinguished from other members of the genus by the following characters: bright blue spot on top of head; series of 4-5 short faint bars on anterior portion of body; 19-23½ branched anal-fin rays; body depth fits 2.1-2.9 times in SL.

Easy
Individual from Thailand.

Laubuka siamensis

Cyprinidae · Fowler, 1939

Max length
60mm SL2.4in SL
Tank
120 × 30cm48 × 12in
Temp
20–28°C68–82°F
pH
6.0–7.5

Considered synonymous with the congener L. laubuca for a number of years, thus reports of that species from anywhere in Indochina actually refer to the current concept of L. siamensis. Given the distribution of L. siamensis, it seems likely that many of the fish entering the aquarium trade are also this species and not L. laubuca. The two species can be distinguished by...

Easy
Wild-collected specimen from western Thailand.

Lepidocephalichthys berdmorei

Cobitidae · Blyth, 1860

Max length
120mm SL5in SL
Tank
75 × 30cm30 × 12in
Temp
20–25°C68–77°F
pH
6.0–8.0

This is one of the most frequently-traded members of the genus and is an excellent choice for those new to keeping loaches. It's distinguishable from congeners by a combination of characters including: relatively large adult size (to at least 80 mm SL); rounded/truncate caud...

Easy
This is one of the few species in the genus to possess a forked caudal fin.

Lepidocephalichthys furcatus

Cobitidae · de Beaufort, 1933

Max length
50mm SL2.0in SL
Tank
45 × 30cm18 × 12in
Temp
23–26°C73–79°F
pH
5.5–7.5

This species is not traded often but is occasionally available as bycatch among shipments of other species. It can be told apart from congeners most easily by the prominent, dorsally-orientated, roughly semi-circular lamina circularis in males, a feature unique within the genus. Other distinguishing characters include a combination of: forked caudal-fin; relatively small adult size; dark <-shaped mark at the base of the caudal-fin; a black spot at the base of branched caudal-fin rays 3-5.

Moderate
Specimen from western Thailand.

Lepidocephalichthys hasselti

Cobitidae · Valenciennes, 1846

Max length
60mm SL2.4in SL
Tank
60 × 30cm24 × 12in
Temp
23–26°C73–79°F
pH
5.5–7.5

At one locality close to Ban Na Hwai, Chiang Mai Province, Thailand L. hasselti was collected from a shallow (<0.5 m) pool in a swampy zone between forest and rice fields. The substrate was of mud, there was no aquatic vegetation and it was being used as drinking water by local animals, with the only effluent connected to a 'small creek'. Other species found there were Physoschistura pseudobrunneana, Rasbora hobelmani and Systomus cf. orphoides.

Easy
Specimen from the Mun River, Thailand, type locality of the species.

Lepidocephalichthys kranos

Cobitidae · Havird & Page, 2010

Max length
45mm SL1.8in SL
Tank
60 × 30cm24 × 12in
Temp
23–26°C73–79°F
pH
5.5–7.5

The family Cobitidae, often referred to as 'true' loaches, is widely-distributed across most of Eurasia with the Indian subcontinent, Southeast Asia and China representing particular centres of species diversity. Phylogenetic analyses by Tang et al. (2006), Šlechtová et al. (2007) and Šlechtová et a...

Easy
Specimen from the Salween river basin, western Thailand.

Lepidocephalichthys micropogon

Cobitidae · Blyth, 1860

Max length
55mm SL2.2in SL
Tank
60 × 30cm24 × 12in
Temp
20–25°C68–77°F
pH
6.0–7.5

According to Kottelat (2012) L. manipurensis Arunkumar, 2000, which was described from Moreh, Manipur state, northeastern India, close to the border with Myanmar, is a syonym of L. micropogon. Havird and Page (2010) differentiate the two based on caudal-fin patterning, predorsal length and ver...

Moderate
Specimen from eastern Thailand.

Lepidocephalichthys zeppelini

Cobitidae · Havird & Tangjitjaroen, 2010

Max length
26mm SL1.0in SL
Tank
45 × 30cm18 × 12in
Temp
20–26°C68–79°F
pH
6.0–7.5

The type locality consisted of remnant ephemeral pools in otherwise dry agricultural land, and many adults were collected from such habitats. Other species present included the congener L. hasselti plus members of Anabas, 'Puntius', Rasbora, Channa, and Hampala.

Moderate
Adult specimen.

Lepidocephalus macrochir

Cobitidae · Bleeker, 1854

Max length
90mm SL3.5in SL
Tank
75 × 30cm30 × 12in
Temp
22–26°C72–79°F
pH
5.5–7.5

The distribution records for this species are somewhat confusing. It was described from the confluence of the Lamatang and Enim rivers, Palambang Province, Sumatra and has since been recorded from Thailand (Chao Phraya River), Peninsular Malaysia (Pahang River) plus the islands of Java (Solo River) and Borneo (Kapuas and Barito rivers).

Moderate
Specimen from Thailand.

Lobocheilos melanotaenia

Cyprinidae · Fowler, 1935

Max length
200mm SL8in SL
Tank
180 × 60cm72 × 24in
Temp
20–26°C68–79°F
pH
6.0–8.0

The majority of Lobocheilos species are endemic to the Greater Sunda Islands of Borneo, Sumatra, and Java, and are uncommon in the aquarium trade, but the widespread Indochinese taxa L. melanotaenia and L. rhabdoura are available on a sporadic basis. L. melanotaenia can be distinguished from L. rhabdoura by the following comb...

Moderate
Individual in its natural habitat, Thailand.

Lobocheilos rhabdoura

Cyprinidae · Fowler, 1934

Max length
220mm SL9in SL
Tank
180 × 60cm72 × 24in
Temp
20–26°C68–79°F
pH
6.0–8.0

Lobocheilos species are specialised grazers of periphyton, benthic algae, and other organisms which grow attached to rocks and other solid surfaces, and they typically leave visible scrape marks in places where they have been feeding. They are by no means herbivorous and should be offered meaty foods such as live or frozen chironomid larvae (bloodworm), Tubifex, Artemia, chopped prawn, etc., along with good quality, sinking dried products, at lea...

Moderate
Specimen from the Mekong River.

Luciosoma bleekeri

Cyprinidae · Steindachner, 1878

Max length
210mm SL8in SL
Tank
240 × 60cm96 × 24in
Temp
20–26°C68–79°F
pH
6.0–8.0

L. bleekeri is most-easily distinguished from the congener L. setigerum, with which it is frequently confused, by absence (vs. presence) of a series of black spots on the lateral line scales.

Moderate
Specimen from Thailand.

Luciosoma setigerumApollo Shark

Cyprinidae · Valenciennes, 1842

Max length
220mm SL9in SL
Tank
240 × 60cm96 × 24in
Temp
20–26°C68–79°F
pH
6.0–8.0

There is a fish of unknown geographical origin which matches the majority of diagnostic features for L. setigerum with the exception that the dark lateral stripe is absent in the anterior portion of the body and is not composed of interconnected spots. It is relatively common in the aquarium trade and included here as L. cf. setigerum until a confirmed identity is established.

Moderate
Adult specimen from the Singapore aquarium trade.

Microdevario kubotai

Cyprinidae · Kottelat & Witte, 1999

Max length
20mm SL0.8in SL
Tank
60 × 30cm24 × 12in
Temp
20–27°C68–81°F
pH
6.0–7.0

Apparently inhabits calm to moderately-flowing stretches of well-oxygenated headwaters and minor tributaries. Such habitats tend to comprise transparent water, substrates of sand, gravel, rocks, boulders, and patches of leaf litter, with submerged driftwood, roots of riparian vegetation, and aquatic vegetation in places.

Easy
Specimen from western Thailand.

Mystacoleucus argenteus

Cyprinidae · Day, 1888

Max length
140mm SL6in SL
Tank
120 × 45cm48 × 18in
Temp
20–27°C68–81°F
pH
6.0–7.5

All Mystacoleucus species possess a procumbent predorsal spine orientated towards the head, though it can be difficult to spot with the naked eye. This can become entangled in an aquarium net so care must be taken when handling the fish. The trait is shared by members of Tor, Spinibarbus and Paraspinibarbus although there exists no strong evidence to suggest that these genera form a monophyletic lineage and it is...

Easy
Specimen from Thailand.

Mystacoleucus greenwayi

Cyprinidae · Pellegrin & Fang, 1940

Max length
100mm SL3.9in SL
Tank
120 × 45cm48 × 18in
Temp
20–27°C68–81°F
pH
6.0–7.5

Predominantly a riverine fish favouring clear, well-oxygenated, running water with substrates of sand or gravel and often present in rock and boulder-filled headwater streams. In the Mun River, close to the Pak Mun dam, Thailand, sympatric species included Hampala dispar, Cyclocheilichthys apogon, Osteochilus hasseltii,...

Easy
Adult individual from Thailand.

Mystacoleucus obtusirostris

Cyprinidae · Valenciennes, 1842

Max length
140mm SL6in SL
Tank
120 × 45cm48 × 18in
Temp
20–27°C68–81°F
pH
6.0–8.0

This species is occasionally marketed as 'Burmese Rainbow Barb' in the ornamental trade. others may have been exported in small numbers or as bycatch among shipments of other species. It was referred to as Mystacoleucus marginatus for decades, but that name is a simultaneous subjective synonym of M. obtusirostris following Kottelat (2013).

Easy
N. binotatus is immediately identifiable by its unique colour pattern.

Nemacheilus binotatus

Nemacheilidae · Smith, 1933

Max length
45mm SL1.8in SL
Tank
60 × 30cm24 × 12in
Temp
23–26°C73–79°F
pH
6.0–7.5

N. binotatus is distinguished from similar-looking congeners such as N. longistriatus and N. ornatus by its unique body patterning consisting very simply of two dark stripes, one running along the dorsal surface and the other from the tip of the snout, through the eye and along the flank. There are usually 1-3 small, vertically-orientated spots extending above the lateral stripe between the pectoral-fin and dorsal fins. These are su...

Easy
Specimen from northern Thailand.

Nemacheilus longistriatusLaos Blackline Torpedo Loach

Nemacheilidae · Kottelat, 1990

Max length
125mm SL5in SL
Tank
90 × 30cm36 × 12in
Temp
23–26°C73–79°F
pH
6.5–7.5

Fishes which inhabit similar biotopes in nature constitute the best options, especially peaceful, open water-dwelling cyprinids since the presence of one or two schools can make a visible difference to the confidence of this naturally reclusive loach. Other possibilities include rheoph...

Moderate
A defining character of this species is that the dark bars and saddles on the body are wider than the lighter-coloured interspaces.

Nemacheilus masyaeArrow Loach

Nemacheilidae · Smith, 1933

Max length
70mm SL2.8in SL
Tank
60 × 30cm24 × 12in
Temp
23–26°C73–79°F
pH
6.0–7.5

This species was originally named Nemacheilus masyae but following ICZN rules the spelling was later corrected to N. masyai because it's named after a man. It can be distinguished from the majority of congeners by body patterning comprising 14-18 short, dark vertical bars on each flank, 12-17 saddle-like markings running along the dorsal surface, a dark spot on the caudal peduncle at the termination of the lateral line and a dark blotch in the lower half of the first few dorsal-fin rays.

Easy
This species has unique body patterning within the genus (see 'notes').

Nemacheilus ornatus

Nemacheilidae · Kottelat, 1990

Max length
45mm SL1.8in SL
Tank
60 × 30cm24 × 12in
Temp
23–26°C73–79°F
pH
6.0–7.5

This species is distinguished from similar-looking congeners such as N. longistriatus and N. ornatus by its unique colour pattern consisting of a black lateral body stripe with 9-16 vertically-orientated blotches extending along it both above and below, plus an irregular stripe running along the dorsal surface. The anterior lateral blotch is surrounded by lighter pigment, forming an ocellus similar to that seen in N. binotatus.

Easy
N. pallidus is not common in the aquarium trade.

Nemacheilus pallidus

Nemacheilidae · Kottelat, 1990

Max length
60mm SL2.4in SL
Tank
60 × 30cm24 × 12in
Temp
23–26°C73–79°F
pH
6.0–7.5

The similar-looking N. masyai is sometimes traded as N. pallidus, but the two can be told apart by body depth (14.8-19.1 % in N. pallidus vs. 12.6-17.6 % SL in N. masyai), interorbital width (5.7-8.0 % vs. 4.9-6.8 % SL) and the fact that in N. pallidus the dark body bars and saddles are thinner than the light-coloured interspaces between (vs. wider in N. masyai).

Easy
Adult male individual from the UK aquarium trade.

Nemacheilus platiceps

Nemacheilidae · Kottelat, 1990

Max length
61mm SL2.4in SL
Tank
60 × 30cm24 × 12in
Temp
23–26°C73–79°F
pH
6.0–7.5

This species is only traded occasionally. It's distinguished from congeners by a combination of characters including: 12-16 dark, irregular, vertical bars on body, usually split vertically; lips without furrows; inco...

Easy
Specimen from Terengganu state, northeastern Peninsular Malaysia.

Nemacheilus selangoricus

Nemacheilidae · Duncker, 1904

Max length
60mm SL2.4in SL
Tank
60 × 30cm24 × 12in
Temp
20–25°C68–77°F
pH
5.0–7.5

N. selangoricus is most similar to N. spiniferus since it possesses acuminate scales above and below the lateral line on the caudal peduncle, a feature not shared with any other congener. It can however be distinguished by the following characters: presence of 8-12 very regular dark bars on flanks (vs. 10-13 irregularly-shaped bars in N. spiniferus), 3-5 times...

Easy
This species is very rare in the aquarium hobby.

Opsarius bernatziki

Cyprinidae · Koumans, 1937

Max length
90mm SL3.5in SL
Tank
120 × 45cm48 × 18in
Temp
18–26°C64–79°F
pH
6.0–7.5

Type locality is ' Kapa, northwestern peninsular Thailand', which may refer to modern-day Kapoe district, Ranong province, and additional records exist from other localities in Ranong as well as Phang-nga and Pattani provinces. Although the precise extent of its distribution is unclear it appears to occur in river systems on both sides of the Tennaserim Hills in pen...

Moderate
Specimen collected from the Nu Jiang (river), Yunnan province, China.

Opsarius caudiocellatus

Cyprinidae · Chu, 1984

Max length
86mm SL3.4in SL
Tank
150 × 45cm60 × 18in
Temp
18–24°C64–75°F
pH
6.5–8.0

This species may have appeared in the aquarium trade though probably not under the correct name. It can be told apart from similar-looking congeners by the following combination of characters: presence of a black round spot at the caudal base; dorsal-fin rays black with connecting membranes transparent; posterior dorsal-fin origin located midway between upper angle of gill aperture and caudal-fin base, or slightly closer to the latter.

Moderate
Young adult specimen in the aquarium.

Opsarius infrafasciatus

Cyprinidae · Fowler, 1934

Max length
100mm SL3.9in SL
Tank
120 × 45cm48 × 18in
Temp
18–26°C64–79°F
pH
6.0–8.0

This species has previously been considered synonymous with both O. ornatus and O. pulchellus but is currently considered to be distinct following (Tejavej, 2012). It can be distinguished from congeners by a combination of characters including: small caudal spot presen...

Moderate
Specimen photographed in the field.

Opsarius koratensis

Cyprinidae · Smith, 1931

Max length
100mm SL3.9in SL
Tank
150 × 45cm60 × 18in
Temp
22–30°C72–86°F
pH
6.0–8.0

Inhabits well-oxygenated, low-to-medium gradient, slow to moderate-flowing rivers and streams with substrates of gravel, cobbles, larger boulders and exposed bedrock. At the habitat in our image pH was 7.5, temperature 26°C and cond...

Moderate
Wild -collected adult specimens.

Opsarius ornatus

Cyprinidae · Sauvage, 1883

Max length
110mm SL4in SL
Tank
150 × 60cm60 × 24in
Temp
18–26°C64–79°F
pH
6.0–8.0

Type locality is 'Mé-Nam River, Thailand', with 'Mé-Nam' having been considered an older name for the Chao Phraya river in central and western Thailand prior to this species' redescription by Tejavej (2012). In fact 'menam' is the Thai word for 'river' and thus could refer to any drainage, and B. ornatus is restricted to...

Moderate
Adult male specimen with nuptial colour pattern and breeding tubercules on head.

Opsarius pulchellus

Cyprinidae · Smith, 1931

Max length
110mm SL4in SL
Tank
120 × 45cm48 × 18in
Temp
18–26°C64–79°F
pH
6.0–7.5

This species is traded for aquaria under various names including 'butterfly barb', 'mackerel barb', 'green-barred danio', and 'royal opsarius'. It can be told apart from other memb...

Moderate
Live specimen measuring 80 mm SL collected from the type locality in Sangklaburi District, Maeklong drainage, Kanchanaburi Province, Thailand.

Opsarius signicaudus

Cyprinidae · Tejavej, 2012

Max length
100mm SL3.9in SL
Tank
120 × 45cm48 × 18in
Temp
18–26°C64–79°F
pH
6.0–8.0

O. dogarsinghi and O. bernatziki are the only two Southeast Asian congeners to possess a large blotch at the caudal-fin base but in the former the blotch is vertically-orientated and hardly extends onto the fin itself (vs. laterally-elongate and extending onto the basal fin rays) and long (vs. short) barbels, while th...

Easy
Mature male specimen.

Oryzias dancenaIndian Ricefish

Adrianichthyidae · Hamilton, 1822

Max length
35mm SL1.4in SL
Tank
45 × 30cm18 × 12in
Temp
23–27°C73–81°F
pH
6.5–8.5

This species continues to be mislabelled as O. melastigma, a name currently considered invalid by the majority of recent workers, or O. javanicus, a valid but distinct taxon. Roberts (1998) demonstrated that MClelland's description of Aplocheilus melastigmus, later renamed O. melastigma, does not correspond with any known Oryzias species from the Indian subcontinent or Myanmar since it's said to have a dark spot in the dorsal-fin and an excessively slim body, among other anomalies.

Easy
Specimen from 'Pulau' Pangkor (Pangkor Island), western Peninsular Malaysia.

Oryzias javanicusJavanese Ricefish

Adrianichthyidae · Bleeker, 1854

Max length
35mm SL1.4in SL
Tank
45 × 30cm18 × 12in
Temp
24–29°C75–84°F
pH
7.0–9.0

This species is widely-distributed throughout Peninsular Thailand, Malaysia (Malay Peninsula plus the states of Sabah and Sarawak, Borneo), Singapore and Indonesia, with records from the Riau Archipelago, Sumatra, Java, Borneo, Bali, Lombok, and Sulawesi existing in the latter. Type locality is 'Panimbang River, Perdana, Indonesia'. It's typically found in coastal, normally brac...

Easy
Adult male specimen.

Oryzias mekongensisMekong Ricefish

Adrianichthyidae · Uwa & Magtoon, 1986

Max length
21mm SL0.8in SL
Tank
40 × 20cm16 × 8in
Temp
23–27°C73–81°F
pH
6.0–7.5

It can be further distinguished from congeners by the following combination of characters: small adult size; bright orange-red marginal bands on caudal-fin lobes in males; caudal-fin rounded and elongate; 5-7 dorsal-fin rays; relatively few (13-18) anal-fin rays without bony contact organs, the last ray branched; 6-8 pectoral-fin rays. Members of the family Adrianichthyidae are...

Easy
Male specimen.

Oryzias minutillusDwarf Medaka

Adrianichthyidae · Smith, 1945

Max length
17mm SL0.7in SL
Tank
40 × 20cm16 × 8in
Temp
23–32°C73–90°F
pH
6.0–7.5

Best maintained in a heavily planted set-up, ideally with a dark substrate, patches of dense vegetation, and some open areas. Other décor can consist of twisted roots and pieces of bogwood, while surface vegetation is also appreciated by the fish. When maintained under such conditions they're more likely to display their best colours, and planted aquaria also offer fry a more favourable chance of survival alongside the adults.

Beginner
Male specimen.

Oryzias songkhramensis

Adrianichthyidae · Magtoon, 2010

Max length
20mm SL0.8in SL
Tank
40 × 20cm16 × 8in
Temp
23–30°C73–86°F
pH
6.0–7.5

An exclusive inhabitant of fresh, normally standing, waters including shallow pools, ditches, rice paddies and clear water swamps. The type locality is a small ditch measuring just 3 - 6 metres in width and 0.5 - 2 metres deep. The water was clear and the substrate composed of sand, detritus and mud with growths of the macrophytes Nymphaea lotus, Jussiaea repens and Hydrilla verticillata.

Beginner
Specimen from an unspecified location in Thailand.

Pangio anguillaris

Cobitidae · Vaillant, 1902

Max length
120mm SL5in SL
Tank
60 × 30cm24 × 12in
Temp
22–29°C72–84°F
pH
6.0–7.5

One of a handful of Pangio spp. traded under the generic name 'eel loach'. Wild populations tend to differ in colour pattern to some extent, with some exhibiting a more intense lateral stripe while others display an irregular pattern of fine dark spots on the body, for example.

Moderate
Specimen from Thailand.

Pangio cuneovirgata

Cobitidae · Raut, 1957

Max length
40mm SL1.6in SL
Tank
45 × 30cm18 × 12in
Temp
21–26°C70–79°F
pH
3.5–7.0

Infrequently encountered in the aquarium trade, most often as bycatch among shipments of similar-looking congeners. It's included in the P. kuhlii group of closely-related species within the genus, and can be distinguished from other members by...

Moderate
Pangio spp. are often associated with submerged leaf litter in nature and this is also appreciated in the aquarium.

Pangio myersiGiant Kuhli Loach

Cobitidae · Harry, 1949

Max length
100mm SL3.9in SL
Tank
60 × 30cm24 × 12in
Temp
21–26°C70–79°F
pH
3.5–7.0

It's included in the P. kuhlii group of closely-related species and can be distinguished from other members by the following combination of characters: 8-11 very broad, quadrangular, regular dark body bars; orange base body colour; caudal-fin either entirely black or with a large black blotch at the base and a submarginal dark bar or row of spots. The latter feature can be useful in identifying young or newly-imported, undernourished specimens which can...

Easy
Specimen from the U. K. aquarium trade.

Pangio oblongaBlack Kuhli Loach

Cobitidae · Valenciennes, 1846

Max length
80mm SL3.1in SL
Tank
60 × 30cm24 × 12in
Temp
21–26°C70–79°F
pH
3.5–7.0

Described from close to the city of Bogor, Jawa Barat (West Java) province on the island of Java, Indonesia, but currently considered widespread with recorded occurrences on Java, Sumatra, Borneo and mainland Peninsular Malaysia. Some populations exhibit lighter...

Easy
Wild specimen from an unspecified locality.

Paracanthocobitis botiaZipper Loach

Nemacheilidae · Hamilton, 1822

Max length
152mm SL6in SL
Tank
75 × 30cm30 × 12in
Temp
21–26°C70–79°F
pH
6.0–7.5

Traded under various names including 'mottled', 'eyepot', 'sand' and 'striped' loach. It's perhaps one of the better choices for those new to keeping nemacheilids being relatively hardy, peaceful and exhibiting some quirky behavioural traits. The characteristic ocellus, a dark marking at the top of the caudal peduncle that resembles an eye, is thought to have some function in predator distraction and is normally more intense in younger specimens.

Easy
Adult specimen from Thailand, collection details unspecified.

Paracanthocobitis pictilisCherry-fin Loach

Nemacheilidae · Kottelat, 2012

Max length
91mm SL3.6in SL
Tank
90 × 30cm36 × 12in
Temp
21–26°C70–79°F
pH
6.5–7.5

Prior to description this species was considered to represent, and traded as, A. rubidipinnis, but that species is apparently endemic to the lower Irrawaddy basin in Myanmar and unknown in the aquarium hobby. Male individuals of A. pictilis, A. botia and A. mandalaysensis possess a suborbital slit rather than suborbital flap which immediately distinguishes...

Moderate
Female specimen of Acanthocobitis zonalternans.

Paracanthocobitis zonalternans

Nemacheilidae · Blyth, 1860

Max length
78mm SL3.1in SL
Tank
60 × 30cm24 × 12in
Temp
20–25°C68–77°F
pH
6.0–7.5

According to Kottelat (1990) the chief distinguishing characters for the genus are: possession of 9-18½ branched dorsal-fin rays; colour pattern without black basal caudal bar, but with an ocellus at upper base of caudal-fin; upper lip with or without several rows of papillae; lower lip with a broad median interruption and a widened, papillated pad on each side.

Easy
Wild-collected individual from northern Thailand.

Pethia stoliczkana

Cyprinidae · Day, 1871

Max length
50mm SL2.0in SL
Tank
75 × 30cm30 × 12in
Temp
18–26°C64–79°F
pH
6.0–7.5

This species is confused with P. ticto in much of the available literature and is sometimes listed as a synonym of it. Although some populations of the two species possess a similar colour pattern (there are reports of a P. ticto variant from the south of West Bengal state in India with a red, black-flecked dorsal-fin, for example) they do not occur in the same waters in nature and can be distinguished by examining the lateral line. This is complete in...

Easy
Specimen from southern Thailand.

Pseudohomaloptera leonardi

Balitoridae · Hora, 1941

Max length
70mm SL2.8in SL
Tank
80 × 30cm31 × 12in
Temp
20–25.5°C68–78°F
pH
6.0–7.5

Type locality is given as 'Kuala Tahan, Pahang (King George V National Park)' which corresponds to the village of Kuala Tahan in Pahang state, central Peninsular Malaysia. The settlement is located at the confluence of the Tahan and Tembiling Rivers which form part of the Pahang river basin, while the national park was re...

Moderate
H. sexmaculata in its natural habitat, Chao Phraya river system, Thailand.

Pseudohomaloptera sexmaculata

Balitoridae · Fowler, 1934

Max length
70mm SL2.8in SL
Tank
80 × 30cm31 × 12in
Temp
20–25.5°C68–78°F
pH
6.0–7.5

H. sexmaculata is very similar to H. leonardi but can be told apart since it possesses 2 simple and 12-14 branched pectoral-fin rays (versus 6 simple and 11 branched rays). Both of these species are sometimes misidentified as H. yunnanensis which has 7 simple and 12 branched pectoral-fin rays.

Moderate
Unlike in other members of the genus, the dark blotch on the dorsal-fin does not connect with the third body bar.

Puntigrus partipentazona

Cyprinidae · Fowler, 1934

Max length
40mm SL1.6in SL
Tank
80 × 30cm31 × 12in
Temp
20–26°C68–79°F
pH
5.0–7.0

Recorded from numerous river basins in Vietnam, Cambodia, Laos, Thailand, and Peninsular Malaysia, including the Mekong, Chao Phraya, Mae Khlong, Chanthaburi, Tapi, Golok, Terengganu, Pahang, Endau, and Muar. Type locality is 'Kratt, southeastern Siam', which corresponds to modern-day Trat Province, Thailand.

Easy
Subadult individual from Thailand.

Puntius cholaSwamp Barb

Cyprinidae · Hamilton, 1822

Max length
130mm SL5in SL
Tank
120 × 45cm48 × 18in
Temp
18–26°C64–79°F
pH
5.5–8.0

P. chola was retained in Puntius sensu stricto, of which members are defined by the following combination of characters: adult size usually less than 120 mm SL; maxillary barbels absent or present; rostral barbels absent; 3-4 unbranched and 8 branched dorsal-fin rays; 3 unbranched and 5 branched anal-fin rays; last unbranched dorsal-fin ray weak or strong and unserrated; lateral line complete with 22-28 pored body scales...

Easy
Pair of R. dorsinotata; female at top.

Rasbora dorsinotata

Cyprinidae · Kottelat, 1987

Max length
43mm SL1.7in SL
Tank
90 × 30cm36 × 12in
Temp
20–25°C68–77°F
pH
6.0–7.5

Type locality is 'Mae Nam Huey Bon, kilometer 45 on road from Amphoe ThaWang Pha to Amphoe Chiang Kham, Chiang Rai Province, Thailand', and this species appears restricted to the Mekong and upper Chao Phraya river basins in northern Thailand and northern Laos. The specimens pictured here were collected from th...

Easy
Young aduit male individual from the Nan River, northern Thailand.

Rhinogobius chiengmaiensisChiangmai Stream Goby

Gobiidae · Fowler, 1934

Max length
50mm SL2.0in SL
Tank
60 × 30cm24 × 12in
Temp
18–26°C64–79°F
pH
6.0–8.0

This species has been exported for the ornamental trade but often labelled as the congener R. mekongianus. Although the two do appear relatively similar R. chiengmaiensis can be identified by a combination of external characters including: presence of 5 irregular dark markings on the body (vs. 7-8 i...

Moderate
Adult male in its natural habitat.

Rhinogobius mekongianus

Gobiidae · Pellegrin & Fang, 1940

Max length
50mm SL2.0in SL
Tank
60 × 30cm24 × 12in
Temp
18–26°C64–79°F
pH
6.0–7.5

Known from various parts of the middle and upper Mekong river basins with record existing from the Nam Tha, Nam Ou, Nam Khan, Nam Lik, Nam Ngum and Nam Mang tributary systems in Laos, the Nam Noeua (a tributary of Nam Ou) in Vietnam, and the Mae Nam Kok in Thailand. Occurrences in the Chao Phraya drainage in central Thailand most likely refer to the congener R. chiengmaiensis.

Moderate
Adult specimen - note the high dorsal adipose crest on the caudal peduncle, a character typical of this species.

Schistura alticrista

Nemacheilidae · Kottelat, 1990

Max length
75mm SL3.0in SL
Tank
90 × 30cm36 × 12in
Temp
21–26°C70–79°F
pH
6.0–7.5

This species is very rare in the aquarium trade but available on occasion. It has 8-9 darkish body bars which usually split vertically as the fish mature, and like some conspecifics possesses a prominent dorsal adipose crest on the caudal peduncle. Schistura is the most species-rich genus among...

Moderate
Freshly-collected specimen from Kanchanaburi province, western Thailand.

Schistura aurantiaca

Nemacheilidae · Plongsesthee, Page & Beamish, 2011

Max length
40mm SL1.6in SL
Tank
75 × 30cm30 × 12in
Temp
20–26°C68–79°F
pH
6.5–8.0

During collections of the type series stream width was found to vary seasonally but was never wider than 9.1 metres. Water depth was 10-40 cm, flow rate 20-70 cm/s−1, and substrates comprised small to medium-sized rocks. Water temperature was seasonally variable but always within the range 20-26°C/68-78.8°F, pH was 6.5-7.9, oxygen 7.4-8.5 mg/l−1, ammonia, nitrate and total iron were 0.01, < 0.03 and < 0.5 mg/l−1, respectively, and alkalinity was aro...

Moderate
This species has two dark vertical bars below the dorsal-fin and lacks black markings at the base of the caudal-fin.

Schistura balteataSumo Loach

Nemacheilidae · Rendahl, 1948

Max length
80mm SL3.1in SL
Tank
90 × 30cm36 × 12in
Temp
22–26°C72–79°F
pH
6.0–7.5

This species is quite uncommon in the aquarium hobby although its name is sometimes used in reference to the similar-looking, apparently undescribed congener S. cf. balteata, and both are also traded as 'sumo loach', 'tri-banded sumo loach', and 'orange saddle-back loach'. Following Kottelat (1990) it's diagnosed by the following combination of characters: unique colour pattern consisting of two da...

Moderate
Schistura sp. cf. balteata; 'pink' form.

Schistura cf. balteataSumo Loach II

Nemacheilidae · authority not recorded

Max length
80mm SL3.1in SL
Tank
90 × 30cm36 × 12in
Temp
22–26°C72–79°F
pH
6.5–7.5

This apparently undescribed species has been available in the hobby since around 2006 and has been traded under several trade names of which others include 'tri-band sumo loach' and 'chubby loach'. The name 'Sumo II' is now in wide use to distinguish it from the real S. balteata since both have been traded as 'Sumo loach'...

Moderate
Wild-collected specimen from Lampong province, northern Thailand.

Schistura geisleri

Nemacheilidae · Kottelat, 1990

Max length
35mm SL1.4in SL
Tank
60 × 30cm24 × 12in
Temp
21–26°C70–79°F
pH
6.0–7.5

Fishes which inhabit similar biotopes in nature constitute the best options, especially peaceful, open water-dwelling cyprinids since the presence of one or two schools can make a visible difference to the confidence of this naturally reclusive loach.

Easy
Young adult specimen from northeastern Thailand.

Schistura kengtungensis

Nemacheilidae · Fowler, 1936

Max length
65mm SL2.6in SL
Tank
90 × 30cm36 × 12in
Temp
18–24°C64–75°F
pH
6.0–7.5

This species is distributed in the middle Mekong River basin in north and northeastern Thailand, Myanmar and Xishuangbanna Dai Autonomous Prefecture, Yunnan province, southern China, and is also known from the Nam Beng, Nam Tha and Nam Yuoan drainages in Laos. Type locality is 'Laun We (Loi Mw...

Moderate
Typically-patterned adult male specimen from the UK aquarium trade.

Schistura kohchangensisOrnate Tiger Sand Loach

Nemacheilidae · Smith, 1933

Max length
75mm SL3.0in SL
Tank
90 × 30cm36 × 12in
Temp
20–26°C68–79°F
pH
6.0–7.5

On Koh Chang one habitat consisted of a stream flowing from the waterfall Nam Tok Mai Yom which empties into the Gulf of Thailand after less than 1 km. The stream was dry in its lower reaches and had a substrate of boulders and pebbles. Sympatric fi...

Moderate
This species has a distinctive colour pattern (see 'Notes')...

Schistura maepaiensis

Nemacheilidae · Kottelat, 1990

Max length
45mm SL1.8in SL
Tank
80 × 30cm31 × 12in
Temp
20–26°C68–79°F
pH
6.0–7.5

The type locality originally consisted of a shallow (0.5 - 1.5 m deep) stream with a substrate of rocks and boulders and flow varying from 'moderate to swift'. When the holotype was collected there in 1980 sympatric species included Acanthocobitis zonalternans, Puntius orphoides, Pethia ticto, Raiamas guttatus, Barilius barnoides, Mystacoleucus argenteus and Mastacembelus armatus plus unidentified members of Crossocheilus an...

Moderate
Specimen from Thailand.

Schistura nicholsi

Nemacheilidae · Smith, 1933

Max length
74mm SL2.9in SL
Tank
120 × 30cm48 × 12in
Temp
20–26°C68–79°F
pH
6.0–7.5

This species is sometimes traded for aquaria but its name also appears to have been widely misapplied to other fishes. It can be identified via the following combination of characters: presence of 8-10 quite regular dark bars...

Moderate
Adult specimen.

Schistura pridiiMini Dragon Loach

Nemacheilidae · Vidthayanon, 2003

Max length
40mm SL1.6in SL
Tank
60 × 30cm24 × 12in
Temp
18–24°C64–75°F
pH
7.0–8.5

Endemic to a handful of tributary streams within the upper Chao Phraya river system in northern Thailand. Six populations are known to date, with the majority lying inside the Doi Chiang Dao Wildlife Sanctuary. Some of its habitats are under threat by over-grazing, deforestation, deliberate forest fires, and collection for the aquarium trade.

Moderate
Wild-collected subadult.

Schistura robertsi

Nemacheilidae · Kottelat, 1990

Max length
56mm SL2.2in SL
Tank
80 × 30cm31 × 12in
Temp
18–30°C64–86°F
pH
6.0–8.0

Should not prove difficult to maintain under the correct conditions. We strongly recommend keeping it in a tank designed to resemble a flowing stream or river with a substrate of variably-sized rocks, sand, fine gravel, and some water-worn boulders. This can be further furnished wit...

Moderate
Specimen from northern Thailand.

Schistura schultzi

Nemacheilidae · Smith, 1945

Max length
93mm SL3.7in SL
Tank
120 × 30cm48 × 12in
Temp
16–24°C61–75°F
pH
6.0–8.0

There appears to be some discrepancy between Smith's original description and Kottelat (1990) in that Smith states the fish is a member of a group of species lacking an ocellus at the upper caudal-fin base, whereas Kottelat mentions the presence of 'a black spot at upper extremity of caudal-fin base, surrounded by a whitish area'.

Moderate
Recently-deceased specimen.

Schistura spilota

Nemacheilidae · Fowler, 1934

Max length
100mm SL3.9in SL
Tank
120 × 30cm48 × 12in
Temp
20–26°C68–79°F
pH
6.0–7.5

Not a commonly species in the aquarium hobby but sporadically available in shipments of wild fishes from Thailand. Following Kottelat (1990) it's a member of a group of species possessing a complete or near-complete lateral line, 8 ½ branched dorsal-fin rays, 17 branched caudal-fin rays and lacking sexual dimorphism (the latter is not strictly true - see above). Its colour pattern is quite distinctive, howe...

Moderate
This species has 7-8 dark bars on each flank which are equal in width, or slightly wider than, the pale interspaces between.

Serpenticobitis zonata

Serpenticobitidae · Kottelat, 1998

Max length
50mm SL2.0in SL
Tank
75 × 30cm30 × 12in
Temp
26°C79°F
pH
6.0–7.0

Fish sold under the name S. zonata are sporadically available in the aquarium trade but the majority appear to be the congener S. octozona. The genus currently contains just three members all of which are known only from the Mekong basin. S. octozona is the type species and separ...

Moderate
Adult specimen with typical body patterning.

Syncrossus beaufortiChameleon Loach

Botiidae · Smith, 1931

Max length
250mm SL10in SL
Tank
150 × 45cm60 × 18in
Temp
22–30°C72–86°F
pH
6.0–7.5

This species is very similar in appearance to S. berdmorei which is native to India and Myanmar, and has been widely mislabelled under that name in older aquarium literature. The two can appear identical on first glance but there are some notable differences, most obviously possession of 9-10 branchedrays in S. beauforti vs. 11-14 in S. bermorei, and the fact that even young specimens of S. beauforti exhibit laterally-orientated rows of small, dark markings running across the ...

Moderate
Subadult specimen.

Syncrossus helodesBanded Tiger Loach

Botiidae · Sauvage, 1876

Max length
300mm SL12in SL
Tank
180 × 45cm72 × 18in
Temp
24–30°C75–86°F
pH
6.0–7.5

This species is sometimes confused with S. hymenophysa, native to the Greater Sunda Islands and Peninsular Malaysia, but differs in several ways, the most immediately identifiable of which are possession of small, irregular, dark markings in the lower half of the body and lack of a dark spot in the dorsal-fin. It also has 10-12 vertical body bars...

Moderate
P. orphoides is a rarely-traded species.

Systomus orphoides

Cyprinidae · Valenciennes, 1842

Max length
250mm SL10in SL
Tank
200 × 60cm79 × 24in
Temp
18–26°C64–79°F
pH
6.0–8.0

The genus Puntius is currently viewed as something of a catch-all for well over 100 species of small to mid-sized cyprinid. Most experts agree that a full revision is required with the likely outcome that many species will be placed into new or different genera since it is clearly polyphyletic. When describing the grouping in 1822 Hamilton identified the defining characteristics as: presence or absence o...

Moderate
Adult male.

Trichopsis pumilaSparkling Gourami

Osphronemidae · Arnold, 1936

Max length
40mm SL1.6in SL
Tank
45 × 30cm18 × 12in
Temp
22–28°C72–82°F
pH
5.0–7.5

It can be distinguished from congeners by its small adult size and presence of a single solid dark midlateral stripe on the body, above which is a series of dark blotches forming a second stripe. In the similar but larger, T. schalleri the upper stripe is more variable depending on the mood of the fish, sometimes fading entirely.

Beginner
Male specimen from Đồng Tháp province, southern Vietnam.

Trichopsis schalleri

Osphronemidae · Ladiges, 1962

Max length
50mm SL2.0in SL
Tank
60 × 30cm24 × 12in
Temp
22–28°C72–82°F
pH
5.0–7.5

Known from the lower Mekong River basin in Laos, Thailand, Cambodia, and Vietnam, plus tributaries of the Chao Phraya watershed in central Thailand, and drainages between the Chao Phraya and Mekong in eastern Thailand. Type locality is 'Nam-Mun at Korat, 135 miles northeast of Bangkok, Thailand'.

Beginner
Specimen from Kota Tinggi, Johor state, Peninsular Malaysia.

Trichopsis vittataCroaking gourami

Osphronemidae · Cuvier, in Cuvier & Valenciennes, 1831

Max length
70mm SL2.8in SL
Tank
60 × 30cm24 × 12in
Temp
22–28°C72–82°F
pH
5.0–7.5

The common name is derived from the ability of genus members to produce audible sounds via a specialised pectoral mechanism which is unique within the family Osphronemidae. The structure comprises modified pectoral-fin tendons and muscles which are stretched and plucked by basal elevations of two fin rays in a similar way to guitar strings via rapid beating of the fins. The pectoral-fins beat alternately, each able to generate short or long bursts of sound. These sounds are produced by both sexes, predom...

Beginner
Adult specimen from the Singapore aquarium trade.

Trigonostigma espeiLambchop Rasbora

Cyprinidae · Meinken, 1967

Max length
30mm SL1.2in SL
Tank
60 × 30cm24 × 12in
Temp
23–28°C73–82°F
pH
5.5–7.5

This species is very peaceful indeed making it an ideal resident of the well-maintained community tank. As it places no extreme demands in terms of water chemistry it can be combined with many of the most popular fish in the hobby including other small cyprinids as well as tetras, livebearers, dwarf cichlids, catfishes, and loaches. As always when selecting a compatible community of fish thorough research is essential and its small adult size must be a consideration, however.

Easy
T. heteromorpha is one of the 'classic' aquarium fishes.

Trigonostigma heteromorphaHarlequin

Cyprinidae · Duncker, 1904

Max length
45mm SL1.8in SL
Tank
60 × 30cm24 × 12in
Temp
21–28°C70–82°F
pH
5.0–7.5

T. heteromorpha was first exported for aquaria in the early 1900s and has gone on to become one of the most familiar, enduring species in the hobby. It has suffered as a result of its popularity to a certain extent with the mass-produced fish we see today lacking much of the colour seen in wild specimens and even exhibiting morphological deformities in some cases. Several selectively-bred ornamental strains have also...

Easy
Well-conditioned adult male of Trigonostigma somphongsi.

Trigonostigma somphongsi

Cyprinidae · Meinken, 1958

Max length
30mm SL1.2in SL
Tank
60 × 30cm24 × 12in
Temp
22–26°C72–79°F
pH
5.0–7.0

T. somphongsi is exceptionally rare both in nature and the hobby and was considered potentially extinct for around a dozen years before a trio were imported to Germany as contaminants among a batch of Boraras urophthalmoides in 2006. Since then it has been successfully bred and distributed to various experts, mostly in Thailand and Germany, in the hope of establishing a sustainable captive population. The possibility of a...

Moderate
This species is much sought after by loach enthusiasts.

Vaillantella maassiFork-tailed Loach

Vaillantellidae · Weber & de Beaufort, 1912

Max length
125mm SL5in SL
Tank
120 × 30cm48 × 12in
Temp
23–29°C73–84°F
pH
3.5–7.2

This species is traded under various names including 'chocolate scissor-tailed loach', chocolate long-finned loach', 'red line cobra loach', 'spiny eel loach' and 'dragon loach'. It's apparently difficult to find in its natural habitats and thus time-consuming to collect, meaning it's rarely traded in numbers, sought after by enthusiasts and tends to carry a relatively high price tag when available. The genus currently contains just three...

Easy
Specimens from the German aquarium trade.

Xenentodon cancilaFreshwater Needlefish

Belonidae · Hamilton, 1822

Max length
350mm SL14in SL
Tank
180 × 60cm72 × 24in
Temp
18–30°C64–86°F
pH
6.0–8.0

X. cancila is often seen referred to as 'freshwater garfish', and although it does superficially resemble the true gars of the family Lepisosteidae, it's actually a member of the Belonidae, or needlefishes, the majority of which are marine or estuarine in existence. There are currently just two species in the genus although the probable existence of a third member has been noted by Roberts (1989) among oth...

Moderate
Specimen in its natural habitat, Khwae Noi basin, upper Mae khlong drainage, western Thailand.

Xenentodon canciloides

Belonidae · Bleeker, 1854

Max length
300mm SL12in SL
Tank
180 × 60cm72 × 24in
Temp
18–26°C64–79°F
pH
6.0–8.0

This species is a near-exclusive inhabitant of the upper water column and appreciates surface cover in the form of floating or overhanging vegetation. Other décor is relatively unimportant but can consist of a sandy substrate with leaf litter plus some large driftwood branches and twisted roots. Plants which can grow rooted in sand can al...

Moderate
Subadult specimen with traces of juvenile patterning (dark, vertical bars on body) still apparent.

Yasuhikotakia eosSun Loach

Botiidae · Taki, 1972

Max length
110mm SL4in SL
Tank
120 × 30cm48 × 12in
Temp
23–28°C73–82°F
pH
6.0–7.5

Y. eos isn't as commonly-traded as it once was but is still available occasionally. It's difficult to confuse with any other member of the genus due to its colour pattern consisting of yellow to reddish brown base body colour (can appear greyish in some specimens, especially post-import or when introduced to a new aquarium) with a metallic green/blue golden sheen and large darkish marking on either side of the caudal peduncle. The fins can be yellowish to reddish, and the dorsal and c...

Moderate
The red-finned form of this species is rarely-traded. Image shows a young adult specimen.

Yasuhikotakia leconteiSilver Loach

Botiidae · Fowler, 1937

Max length
150mm SL6in SL
Tank
120 × 45cm48 × 18in
Temp
23–28°C73–82°F
pH
6.0–8.0

This species is sometimes confused with Y. modesta though in reality the two are readily distinguishable from one another by body shape since Y. lecontei is a slimmer, more elongate fish. Further, in Y. lecontei the overall body colouration is usually brownish with a gold/green sheen and the dark markings...

Moderate
This is the red-finned form of the species most-often seen in the trade...

Yasuhikotakia modestaRedtail Loach

Botiidae · Bleeker, 1864

Max length
250mm SL10in SL
Tank
150 × 45cm60 × 18in
Temp
23–28°C73–82°F
pH
6.0–8.0

This species is one of the more commonly-encountered botiids in the hobby and is also sold as 'blue', 'orange-finned', or 'red-finned' botia/loach. It's sometimes subject to artificial colouring with bright blue or purple dyes and we strongly recommend you do not purchase such fish (they're illegal in several countries).

Moderate
This species is among the more-commonly-traded botiid loaches.

Yasuhikotakia morletiSkunk Loach

Botiidae · Tirant, 1855

Max length
85mm SL3.3in SL
Tank
120 × 30cm48 × 12in
Temp
23–28°C73–82°F
pH
6.0–7.5

This species is common in the hobby and also sold as 'skunk botia' or 'Hora's loach', the latter in reference to Botia horae Smith, 1931, currently considered a synonym of Y. morleti. It's similar in appearance to the rarely-seen Y. longidorsalis but can be told apart by the fact it has a dark stripe running over the dorsal surface (this giving rise to the vernacular name 'skunk loach') which is lacking in its relative. The two can be further separated...

Moderate
Subadult specimen from West Bengal state, India.

Allenbatrachus grunniensFreshwater Toadfish

Batrachoididae · Linnaeus, 1758

Max length
300mm SL12in SL
Tank
not recorded
Temp
23–28°C73–82°F
pH
7.5–9.0

This species is relatively common in the aquarium hobby but contrary to popular belief is not venomous in any way. Its dorsal and opercular spines can pierce the skin, however, meaning extreme caution is necessary when netting it or performing aquarium maintenance. The genus Allenbatrachus was erected in 1997 to accom...

Moderate
1 field missing
Adult specimen - origin unknown.

Anabas testudineusClimbing Perch

Anabantidae · Bloch, 1792

Max length
200mm SL8in SL
Tank
not recorded
Temp
15–30°C59–86°F
pH
5.5–8.0

This species isn't especially popular in the aquarium trade but is undoubtedly interesting despite its lack of colour. In addition to its survival ability in the absence of water it's also capable of producing audible sounds though the purpose of these has not been fully-studied. Naturally-occurring xanthic and albino forms have also been recorded. There is considerable confusion as to the taxonomic status of the two species currently occupying this genus, with ichthyologists widely...

Moderate
1 field missing
This species is easily told apart from congeners by presence of dark blotches on the flanks.

Bagarius suchusCrocodile Catfish

Sisoridae · Roberts, 1983

Max length
700mm SL28in SL
Tank
not recorded
Temp
18–23°C64–73°F
pH
6.0–7.5

The genus Bagarius is distinguished from all other genera in the putative subfamily Sisoridae by having markedly heterodont teeth in the lower jaw. Teeth are present in two or three outer rows of relatively numerous, close-set conical teeth, and one or two inner rows of less numerous, widely separated, and much larger conical teeth (vs. dentition of the lower jaw consisting of only small conical teeth, or a roughened bony plate).

Moderate
1 field missing
Juvenile from the German aquarium trade.

Bagarius yarrelliGoonch

Sisoridae · Sykes, 1839

Max length
2000mm SL79in SL
Tank
not recorded
Temp
16–23°C61–73°F
pH
6.0–7.5

This species is clearly unsuitable for the home aquarium given its eventual size and natural behaviour, and we know of only a handful of private aquarists with the facilities required to house it long-term. The grouping currently contains four species but is in urgent need of review with a number of additional taxa thought to exist and B. yarrelli possibly representing a synonym of B. bagarius.

Moderate
1 field missing
Adult specimen from southern Thailand.

Channa marulioidesEmperor Snakehead

Channidae · Bleeker, 1851

Max length
650mm SL26in SL
Tank
not recorded
Temp
22–30°C72–86°F
pH
6.0–8.0

This species is often confused with the nominal congeners C. marulius (Hamilton, 1822) and C. melanoptera (Bleeker, 1855) with all three presenting taxonomic problems. For example, C. marulioides exhibits a number of variations in colour pattern depending on collection locality with the most common possessing a brownish base colour with a series of dark, chevron-like markings along each flank and some scales margined posteriorly in white.

Moderate
1 field missing
Specimen measuring ca. 400 mm TL collected from the Bhagirathi River at Simurali in Nadia district, West Bengal state, northeastern India.

Channa maruliusBullseye Snakehead

Channidae · Hamilton, 1822

Max length
600mm SL24in SL
Tank
not recorded
Temp
15–28°C59–82°F
pH
6.0–8.0

This species is also referred to as 'giant', 'great', 'cobra', or 'Indian' snakehead. Although currently-considered to be distributed throughout much of southern Asia it is widely-accepted to represent a complex of related species in need of additional research. A number of geographical variants exhibiting diffe...

Moderate
1 field missing
Young adult individual.

Channa micropeltesGiant Snakehead

Channidae · Cuvier, 1831

Max length
1300mm SL51in SL
Tank
not recorded
Temp
20–30°C68–86°F
pH
6.0–8.0

C. micropeltes is also referred to as 'Indonesian', 'red', or 'redline' snakehead, the latter names in reference to the appearance of juveniles which often appear in the ornamental trade despite its unsuitability for home aquaria. It is somewhat hyperbolised in the media as a fearsome, invasive "monster" fish with a reputation for killing more fish than it can eat, and even the occasional human, although in reality...

Moderate
1 field missing
This species can be told apart from congeners by its distinctive colour pattern.

Chitala blanciRoyal Featherback

Notopteridae · d'Aubenton, 1965

Max length
1200mm SL47in SL
Tank
not recorded
Temp
20–28°C68–82°F
pH
6.0–8.0

This species is also referred to as 'royal knifefish' in the aquarium trade but arguably has no place in the ornamental hobby given its adult size and specialised requirements. It can be distinguished from congeners by presence of many small, dark spots on the anterior portion of the body which merge to form oblique, irregular stripes extending onto the anal and caudal fins posteriorly.

Moderate
1 field missing
Adult individual. The fish behind is the congener C. ornata.

Chitala lopisGiant Featherback

Notopteridae · Bleeker, 1851

Max length
1500mm SL59in SL
Tank
not recorded
Temp
22–28°C72–82°F
pH
6.0–8.0

This species is not collected for the aquarium trade at time of writing. In contrast to other members of the genus older juvenile and adult individuals lack dark markings on the body while the jaw is more pronounced.

Moderate
1 field missing
Subadult individual.

Chitala ornataClown Featherback

Notopteridae · Gray, 1831

Max length
1000mm SL39in SL
Tank
not recorded
Temp
20–28°C68–82°F
pH
6.0–8.0

This species is also referred to as 'clown knifefish' in the aquarium trade. It arguably has no place in the ornamental hobby given its adult size and specialised requirements but remains inexplicably popular and an albino form has even been line-bred for the purpose. It can be distinguished from all congeners by presence of one or more rows of large ocellated spots above the base of the anal-fin, but...

Moderate
1 field missing
Specimen in its natural habitat, northwestern Thailand.

Crossocheilus burmanicus

Cyprinidae · Hora, 1936

Max length
120mm SL5in SL
Tank
150 × 45cm60 × 18in
Temp
20–26°C68–79°F
pH
not recorded

We've been unable to obtain a diagnosis for this species to date but it can at least be distinguished from those congeners traded as 'Crossocheilus siamensis' (an invalid name synonymous with C. oblongus, which is itself of questionable identity), 'Siamese algae eater', or 'SAE' by the fact that the dark lateral stripe does not extend into the caudal-fin. Members of Crossocheilus are characterised by...

Moderate
1 field missing
Specimen from Sarawak state, Malaysia (Borneo).

Crossocheilus cobitis

Cyprinidae · Bleeker, 1854

Max length
52mm SL2.0in SL
Tank
100 × 30cm39 × 12in
Temp
20–26°C68–79°F
pH
not recorded

Given its wide natural range it seems logical that this species is or has been available in the aquarium trade, although its correct name may never have been applied. It is told apart from congeners by the following combination of characters: two pairs of barbels; a continuous midlateral stripe from the tip of the snout to the base of the caudal-fin, with a conspicuous small blotch at the posterior extremity, faintly marked on the caudal-fin; a faint mark between the anus and the anal-fin origin in juveniles; a narrow mouth.

Moderate
1 field missing
Large captive specimen pictured at Budapest Aquarium, Hungary.

Ctenopharyngodon idellaGrass Carp

Cyprinidae · Valenciennes, 1844

Max length
1200mm SL47in SL
Tank
not recorded
Temp
0–33°C32–91°F
pH
6.0–9.0

Despite being a wholly unsuitable aquarium subject, C. idella is often traded as such, with an albino form having been developed specifically for the ornamental market. Individuals which have outgrown their aquarium or pond should never be released into natural waters, either, since this species has proven capable of causing serious environmental damage under a wide range of climatic conditions.

Easy
1 field missing
Subadult individual from Thailand.

Cyclocheilos enoplos

Cyprinidae · Bleeker, 1849

Max length
750mm SL30in SL
Tank
not recorded
Temp
20–26°C68–79°F
pH
6.0–8.0

In the Mekong, it has been observed to migrate upstream from Phnom Penh to Khone Falls between November and February, returning downstream between May and August. The downstream migration ends in the Mekong delta area in Vietnam, where the fish remain until the floods reach their peak in October and November. These lower Mekong migrations mostly comprise juveniles and sub-adults, whereas above Khone Falls...

Easy
1 field missing
Adult individual.

Datnioides pulcherSiamese Tiger Perch

Datnioididae · Kottelat, 1998

Max length
400mm SL16in SL
Tank
not recorded
Temp
20–28°C68–82°F
pH
5.5–7.5

The massive decline in wild populations, hypothesised to be in excess of 90% since the mid-1980s, is thought to have been caused by a variety of factors, including habitat alteration due to construction of dams and other infrastructure, removal of riparian vegetation, and urban pollution, plus over fishing for both human consumption and the aquarium trade.

Moderate
1 field missing
Specimen in its natural habitat, Klong-lan waterfall, Kamphaeng Phet province, western Thailand.

Garra fuliginosa

Cyprinidae · Fowler, 1934

Max length
150mm SL6in SL
Tank
150 × 45cm60 × 18in
Temp
20–27°C68–81°F
pH
not recorded

Following Rainboth (1996) distinguishing characters for G. fuliginosa include: presence of rostral and maxillary barbels; a well-developed, trilobed rostrum; possession of 10 gill rakers on the lower portion of the first gill arch; no mid-lateral body stripe; 32-34 lateral line scales; body dark with random lighter scales in places. Kottelat (2001) states that the species can be told apart from other Garra occurring in Laos by a combination of: snout with a secondary rostrum, proboscis about twice as wide...

Moderate
1 field missing
Adult specimens in the aquarium.

Hampala macrolepidotaHampala Barb

Cyprinidae · Kuhl & van Hasselt, 1823

Max length
700mm SL28in SL
Tank
not recorded
Temp
20–26°C68–79°F
pH
5.5–8.0

This species is also known by the vernacular 'jungle perch' or 'sidebar barb' and should not be considered an aquarium subject in all but the most extreme circumstances since it can grow to over 2 feet in length, weigh in excess of 5 kg and is a powerful, pelagic predator. It's also a popular sport fish with a reputation for striking hard.

Moderate
1 field missing
Subadult specimen from Thailand.

Hemibagrus spilopterus

Bagridae · Ng & Rainboth, 1999

Max length
500mm SL20in SL
Tank
not recorded
Temp
20–27°C68–81°F
pH
6.0–8.0

This species is relatively common in the aquarium trade but has been widely misidentified as the congener H. nemurus which is native to Java and may never have been exported for ornamental purposes. Hemibagrus has been divided into a number of putative species groups which may or may not rep...

Moderate
1 field missing
Subadult specimen measuring approximately 230 mm SL collected from the Chao Phraya River, Nakhon Sawan Province, Thailand.

Hemibagrus wyckiiCrystal-eyed Catfish

Bagridae · Bleeker, 1858

Max length
710mm SL28in SL
Tank
not recorded
Temp
20–27°C68–81°F
pH
6.0–8.0

Aggressively territorial and incompatible with other fishes in all but the largest public installations and even then may attack its tankmates. It's also one of few freshwater fishes that appear unafraid of humans meaning care must be exercised when performing maintenance.

Moderate
1 field missing
Subadult individual from Thailand.

Hemibagrus wyckioidesAsian Red Tailed Catfish

Bagridae · Fang & Chaux, 1949

Max length
1300mm SL51in SL
Tank
not recorded
Temp
19–29°C66–84°F
pH
6.0–8.0

Juvenile specimens are sometimes available in the aquarium trade although their purchase is strongly discouraged, and this species probably shouldn't be considered a home aquarium subject at all given its eventual size plus the fact it can live for several decades. H. wyckioides can be told apart from mos...

Moderate
1 field missing
Individual from Thailand.

Hypsibarbus malcolmiGoldfin Tinfoil Barb

Cyprinidae · Smith, 1945

Max length
500mm SL20in SL
Tank
not recorded
Temp
20–26°C68–79°F
pH
6.0–8.0

H. malcolmi is distinguished from congeners by the following combination of characters: 12-17 (usually 14-15) rakers on first gill arch; usually 16 circumpeduncular scale rows; less than 30 lateral line scales; some branched lateral line canals, but branching not extensive, median portion of dorsal-fin dark.

Moderate
1 field missing
Specimen from Thailand.

Incisilabeo behri

Cyprinidae · Fowler, 1937

Max length
550mm SL22in SL
Tank
not recorded
Temp
20–26°C68–79°F
pH
6.0–8.0

The monotypic genus Incisilabeo is separated from the closely-related taxon Bangana by presence of a unique and conspicuous transverse notch across the top of the head, comparable in position to the ethmoid furrow in Bangana species. This notch approaches the eye, and the top of the head bulges forward, with the nostrils located partially beneath this projection and immediately anterior to the eyes. Tubercles cover the upper portion of the rostral fold, lower part of the notch, and upper surface of the forehead projection...

Moderate
1 field missing
Adult individual from Thailand.

Labeo chrysophekadionBlack Shark

Cyprinidae · Bleeker, 1849

Max length
600mm SL24in SL
Tank
not recorded
Temp
20–26°C68–79°F
pH
6.0–8.0

L. chrysophekadion is also known as 'black sharkminnow'. It continues to be available in the ornamental trade despite its patent unsuitability for the home aquarium, and an albino form has been selectively bred for the purpose. It can be distinguished from other members of the genus by the following combination...

Moderate
1 field missing
Subadult specimen from Thailand.

Leptobarbus rubripinnaRed-finned Cigar Shark

Cyprinidae · Fowler, 1937

Max length
1000mm SL39in SL
Tank
not recorded
Temp
20–26°C68–79°F
pH
6.0–8.0

This species was referred to as its congener Leptobarbus hoevenii for a number of decades and continues to be misidentified as such in the aquarium hobby, with both species traded under the same name. It is a popular sport fish in its native countries and is wholly unsuitable for private aquaria. Unfortunately it is...

Moderate
1 field missing
Subadult from the aquarium trade.

Macrochirichthys macrochirusGiant Sword Minnow

Cyprinidae · Valenciennes, 1844

Max length
800mm SL31in SL
Tank
not recorded
Temp
20–26°C68–79°F
pH
6.0–8.0

It is thought to have been extirpated from the Chao Phraya and Mae Klong rivers, Lake Songkhla, and the entire island of Java due to a variety of anthropogenic factors, and the Mekong populations have also been drastically reduced. In particular, it is sensitive to pollution and gillnetting, and is heavily overfished.

Moderate
1 field missing
Specimen measuring 230 mm SL from Kratie province, northeast Cambodia.

Mekongina erythrospila

Cyprinidae · Fowler, 1937

Max length
450mm SL18in SL
Tank
not recorded
Temp
20–26°C68–79°F
pH
6.0–8.0

Endemic to the middle and lower Mekong River system in Laos, Thailand, Cambodia, and Vietnam. Its known range extends from Chiang Rai province, Thailand in the north to Kratie province, Cambodia in the south, and it occurs in several important tributary systems including the Sesan, Srepok, and Tonlé Sap. Type locality is 'Mekong River at Kemarat, Thailand'.

Moderate
1 field missing
Subadult individual in the aquarium.

Notopterus notopterusBronze Featherback

Notopteridae · Pallas, 1769

Max length
600mm SL24in SL
Tank
not recorded
Temp
20–28°C68–82°F
pH
6.0–8.0

This species is also referred to as 'Asian knifefish' or 'ghost knifefish' in the aquarium trade in the aquarium trade but arguably has no place in the ornamental hobby given its adult size and specialised requirements. It is sometimes confused with the African species Xenomystus nigri but is easily told apart by its larger adult size and presence (vs. absence) of a dorsal fin.

Easy
1 field missing
Subadult individual from Thailand.

Phalacronotus apogon

Siluridae · Bleeker, 1851

Max length
700mm SL28in SL
Tank
not recorded
Temp
20–27°C68–81°F
pH
6.0–7.5

P. apogon has formerly been placed within the genera Kryptopterus, Micronema (Rainboth, 1996) and more recently Phalacronotus (Ferraris, 2007) and is an important food fish across much of its native range. It's very similar to P. micronema but can be told apart by its longer head (HL fits 4.6± 5.3 times in...

Moderate
1 field missing
Young adult of the 'red tail golden' form from the German aquarium trade.

Scleropages formosusAsian Arowana

Osteoglossidae · Müller & Schlegel, 1840

Max length
900mm SL35in SL
Tank
not recorded
Temp
22–28°C72–82°F
pH
5.0–8.0

This species is distinguished from its Australian congeners S. jardinii and S. leichardti by possessing a lower number of lateral line scales (21-26 vs 32-36). It occurs naturally in a number of colour forms of which three were elevated to distinct species status in 2003, but the current majority view is that all represent S. formosus pending a detailed review. Kottelat (2013) mentions that the red form may...

Moderate
1 field missing
Specimen from Thailand.

Amblyrhynchichthys micracanthus

Cyprinidae · Ng & Kottelat, 2004

Max length
200mm SL8in SL
Tank
not recorded
Temp
not recorded
pH
not recorded

Native to the Mekong River drainage in Laos (where Vientiane province represents the upper limit of its range), Thailand, Cambodia, and Vietnam, and the Tapi, Chao Phraya, and Mae Klong systems in Thailand. Type locality is '22 kilometers upstream from Phnom Penh, Tonle Sap River, Kandal Province, Cambodia'.

Moderate
3 fields missing
Specimen from the Salween basin, northwestern Thailand.

Bangana devdevi

Cyprinidae · Hora, 1936

Max length
250mm SL10in SL
Tank
not recorded
Temp
not recorded
pH
not recorded

Known with certainty from the Irrawaddy River system in Manipur state, India, and Myanmar, and the Salween watershed in eastern Myanmar and northwestern Thailand. Records from the Red River basin in Vietnam appear questionable. Type locality is 'Burma: Myitkyina District: Mali Hka basin: Phungin Hka;'.

Moderate
3 fields missing
Specimen from the Ataran (known as Kasat in Thailand) River, a tributary system within the larger Salween drainage.

Garra notata

Cyprinidae · Blyth, 1860

Max length
120mm SL5in SL
Tank
not recorded
Temp
not recorded
pH
not recorded

G. notata is one of a number of congeners to lack both a transverse groove and a proboscis on the snout. It also possesses 33-34 lateral line scales and a series of dark spots at the base of the dorsal-fin rays, and lacks scales on the lower portion of the body and abdomen. The genus Garra is a particularly enigmatic grouping with new taxa...

Moderate
3 fields missing
Putative adult male from the German aquarium trade.

Garra salweenica

Cyprinidae · Hora & Mukerji, 1934

Max length
175mm SL7in SL
Tank
not recorded
Temp
not recorded
pH
not recorded

G. salweenica can be distinguished from other congeners inhabiting the Salween watershed by the following combinatuion of characters: body brownish; presence of a trilobed proboscis on the snout; snout blunt; a series of black spots at the base of the central dorsal-fin rays; presence of longitudinal stripes on the posterior portion of the body; a dark marking at the tip of the upper (and lower in some specimens) caudal-fin lobe; body depth 22.4-25.3 % SL.

Moderate
3 fields missing
Specimen from the Nan River, Nan province, northern Thailand.

Garra theunensis

Cyprinidae · Kottelat, 1998

Max length
300mm SL12in SL
Tank
not recorded
Temp
not recorded
pH
not recorded

This species can be distinguished from congeners in Southeast Asia and China by the following combination of characters: plain brown body and fins, sometimes with 6-8 narrow, faintly distinct, longitudinal stripes; snout triangular in dorsal view, with small tubercules and without transverse groove...

Moderate
3 fields missing
Subadult individual from Thailand.

Gymnostomus lineatus

Cyprinidae · Smith, 1945

Max length
150mm SL6in SL
Tank
not recorded
Temp
not recorded
pH
not recorded

Recorded from the middle to lower Mekong river basin in southern China (Yiunnan province), Laos, Thailand, and Cambodia, plus the Chao Phraya watershed in central Thailand. Type locality is 'Thailand: Lam Ton Lang, a tributary of Menam Sak [Mae Nam Pa Sak; Ban Lam Thong Lang, village northwest of Pakjong'.

Moderate
3 fields missing
Specimen from Thailand.

Gymnostomus lobatus

Cyprinidae · Smith, 1945

Max length
150mm SL6in SL
Tank
not recorded
Temp
not recorded
pH
not recorded

G. lobatus can be distinguished from congeners by the following combination of characters: possession of 32-33 + 2-3 lateral line scales; 5½ scale rows between lateral line and base of dorsal-fin; body relatively slender, depth fits 3.7-4.0 times in SL; snout often projecting strongly; body plain silver in colour.

Moderate
3 fields missing
Specimen from the Mekong basin in Thailand.

Gymnostomus ornatapinnis

Cyprinidae · Roberts, 1997

Max length
100mm SL3.9in SL
Tank
not recorded
Temp
not recorded
pH
not recorded

G. ornatapinnis can be distinguished from congeners by the following combination of characters: head small; snout relatively short and blunt; caudal peduncle very deep; pectoral, pelvic, and anal fins usually reddish-orange or rose-tinted; pelvic and anal fins often with white tips; barbels completely absent.

Moderate
3 fields missing
Gymnostomus siamensis NP

Gymnostomus siamensisSiamese Mud Carp

Cyprinidae · Sauvage, 1881

Max length
150mm SL6in SL
Tank
not recorded
Temp
not recorded
pH
not recorded

G. siamensis can be distinguished from congeners by the following combination of characters: possession of 5½ lateral line scales; body relatively deep, depth fits 3.2-3.4 times in SL; head large and broad, width fits 5.5-6.7 times in SL; snout not or only weakly projecting; body plain silver in colour with no dark marking on caudal peduncle.

Moderate
3 fields missing
Subadult specimen from the Mekong basin in Thailand.

Hemibagrus filamentus

Bagridae · Fang & Chaux, 1949

Max length
420mm SL17in SL
Tank
not recorded
Temp
not recorded
pH
not recorded

This species appears to be unknown in the aquarium trade but is a valued food fish within its native range. Hemibagrus has been divided into a number of putative species groups which may or may not represent monophyletic assemblages, and following a major review by Ng and Kottelat (2013) H. filamentus is included in the H. nemurus group.

Moderate
3 fields missing
Subadult individual from western Thailand.

Hemibagrus microphthalmus

Bagridae · Day, 1877

Max length
1500mm SL59in SL
Tank
not recorded
Temp
not recorded
pH
not recorded

This species cannot be considered a suitable home aquarium subject given its eventual size plus the fact it can live for several decades. It can be told apart from most oth...

Moderate
3 fields missing
Adult individual photographed at Leipzig Zoological Garden, Leipzig, Germany.

Hypsibarbus pierreiYellow Eyed Silver Barb

Cyprinidae · Sauvage, 1880

Max length
300mm SL12in SL
Tank
not recorded
Temp
not recorded
pH
not recorded

Known from the middle and lower Mekong basins in Laos, Thailand, Cambodia, and Vietnam, plus the Dong Nai drainage in central Vietnam. Type locality is 'Rapids of Dang-nai, Bien Hoa Province, Thailand', which corresponds to what is now the city of Biên Hòa in Đồng Nai province, southern Vietnam.

Moderate
3 fields missing
Subadult from the Salween basin in northwestern Thailand.

Hypsibarbus salweenensis

Cyprinidae · Rainboth, 1996

Max length
300mm SL12in SL
Tank
not recorded
Temp
not recorded
pH
not recorded

Endemic to the Salween river system in Yunnan province, southern China, eastern Myanmar, and northwestern Thailand. Type locality is 'Salween River midway between Mae Sam Laep and Paleh, Mae Hong Son province, Thailand.'

Moderate
3 fields missing
Subadult from Thailand.

Labeo pierrei

Cyprinidae · Sauvage, 1880

Max length
800mm SL31in SL
Tank
not recorded
Temp
not recorded
pH
not recorded

This species can be distinguished by the following characters: juveniles with brown body and dark marking at base of caudal-fin; 37-42 + 3-4 lateral line scales; 11½ branched dorsal-fin rays; 7½ scale rows between lateral line and dorsal-fin origin; 20-25 predorsal scales; dorsal-fin relatively small with anterior branched rays shorter than head in juveniles, slightly longer than head in adults.

Moderate
3 fields missing
Specimen from Thailand.

Labiobarbus siamensis

Cyprinidae · Sauvage, 1881

Max length
200mm SL8in SL
Tank
not recorded
Temp
not recorded
pH
not recorded

L. siamensis can be distinguished from congeners by the following combination of characters: 39-42 scales in the lateral series; shoulder spot usually absent, but sometimes well-defined; body with longitudinal stripes formed by a spot on each scale; dorsal fin with dusky median stripe and no red coloration; caudal fin dusky, sometimes with reddish coloration, but no well-defined stripes; 20-23 circumpeduncular scales...

Moderate
3 fields missing
Adult individual from Kratie province, northeastern Cambodia.

Mystacoleucus atridorsalis

Cyprinidae · Fowler, 1937

Max length
80mm SL3.1in SL
Tank
not recorded
Temp
not recorded
pH
not recorded

This species can be distinguished from congeners by the following combination of characters: body depth fits 2.5-2.7 times in SL; 28-31 +2-3 lateral line scales; 14-16 circumpeduncular scale rows; 5-5½ scale rows between the lateral line and dorsal-fin origin; a triangular distal blotch on the dorsal-fin; a few body scales with crescent-shaped black edges; a thin dark margin on the dorsal-fin, posterior to the distal blotch; a dark posterior margin on the caudal-fin; normally a single pair of rudimentary barbels present.

Moderate
3 fields missing
Specimen from central Thailand.

Mystacoleucus chilopterus

Cyprinidae · Fowler, 1935

Max length
91mm SL3.6in SL
Tank
not recorded
Temp
not recorded
pH
not recorded

Known from the middle Mekong basin in Laos and Thailand, including the Mun tributary drainage on the Khorat Plateau in northeastern Thailand, plus the Chao Phraya and Mae Klong watersheds in central and western Thailand, respectively. In the Mekong system it may also occur further upriver in Yunnan province, China, while the Khone Falls in Laos appear to represent its downstream limit.

Moderate
3 fields missing
Individual from northeastern Thailand.

Mystacoleucus ectypus

Cyprinidae · Kottelat, 2000

Max length
80mm SL3.1in SL
Tank
not recorded
Temp
not recorded
pH
not recorded

Known from the middle Mekong basin in Laos and Thailand, and may be endemic to the Khorat Plateau. Records exist from the Mun and Songkhram watersheds in northeastern Thailand, and a number of Mekong tributaries in laos, including the Nam Mang and Nam Kou drainages. Type locality is 'Nam Mang downstream of Ban Thabok, between 18°22'25"N, 103°13'30"E, and about 1 kilometer upstream, Vientiane Province, Laos'.

Moderate
3 fields missing
Specimen from Laos.

Mystacoleucus lepturus

Cyprinidae · Huang, 1979

Max length
95mm SL3.7in SL
Tank
not recorded
Temp
not recorded
pH
not recorded

This species can be distinguished from congeners by the following combination of characters: body relatively slender, depth fitting 3.4-3.8 times in SL; 32-33 + 2 lateral line scales; 14 circumpeduncular scale rows; presence of a single pair of barbels; black distal margin on dorsal-fin; numerous body scales with dark, crescent-shaped markings.

Moderate
3 fields missing
This is an endangered, protected species and illegal to collect for the aquarium trade.

Nemacheilus troglocataractus

Nemacheilidae · Kottelat & Géry, 1989

Max length
68mm SL2.7in SL
Tank
not recorded
Temp
not recorded
pH
not recorded

Known only from a single cave system (Tham Sai Yok Noi) near the town of Nam Tok Sai Yok Noi, Sai Yok district, Kanchanaburi Province, Thailand. The headwater stream running through the cave is part of the Khwae Noi river basin, itself a tributary of the upper Mae Klong system. 621 metres of the cave system has repor...

Moderate
3 fields missing
Some individuals of this species have vestigial eyes, while others have none at all.

Schistura deansmarti

Nemacheilidae · Vidthayanon & Kottelat, 2003

Max length
105mm SL4in SL
Tank
not recorded
Temp
not recorded
pH
not recorded

Type locality is 'Tham [=cave] Phra Sai Ngam, about 200 meters from entrance, Thung Salaeng Luang National Park, Phitsanulok Province, Thailand, 16°37'22"N, 100°39'47"E', and this species is endemic to the Tham Phra Sai Ngam cave system. Tham Phra Sai Ngam is a limestone cave system about 1.7 km long and containing a subterranean stre...

Moderate
3 fields missing
Dorsal view of specimen in its natural habitat.

Schistura oedipus

Nemacheilidae · Kottelat, 1988

Max length
80mm SL3.1in SL
Tank
not recorded
Temp
not recorded
pH
not recorded

It's known from five caves in total, the others being Tham Huet, Tham Ban Louk Kow Larm, Tham Nong Pha Cham, and Tham Mae Lana. Streams flowing from these caves drain into the Nam Lang and Nam Khong rivers of the Salween drainage system, and the two easternmost caves, Tham Huet and Tham Nong Pha Cham, are both tributaries of the former.

Moderate
3 fields missing
Subadult from Thailand.

Bagarius bagarius

Sisoridae · Hamilton, 1822

Max length
not recorded
Tank
not recorded
Temp
not recorded
pH
not recorded

There is considerable confusion surrounding the identity of B. bagarius with its name having been widely applied to a relatively small species that is said to reach only 200 mm SL and considered to be common in northern India and much of Indochina.

Moderate
4 fields missing