Basin
Chao Phraya basin
113 profiles across 7 rivers name the Chao Phraya basin's waters as a locality.
- Species
- 113
- Rivers
- 7
- Photographed
- 113 of 113
- Difficulty rated
- 113 of 113
Rivers in this basinspecies recorded from each
Runs through

Acantopsis dialuzonaHorseface Loach
Cobitidae · van Hasselt, 1823
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...

Acrochordonichthys gyrinusFalcate Chameleon Catfish
Akysidae · Vidthayanon & Ng, 2003
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.

Ambastaia nigrolineataBlack-Lined Loach
Botiidae · Kottelat & Chu, 1987
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...

Amblypharyngodon chulabhornaePrincess Carplet
Cyprinidae · Vidthayanon & Kottelat, 1990
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.

Bagrichthys majusculusWhite-Whisker Lancer
Bagridae · Ng, 2002
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...

Bagrichthys obscurus
Bagridae · Ng, 1999
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...

Balitoropsis zollingeri
Balitoridae · Bleeker, 1853
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...

Barbodes binotatusSpotted Barb
Cyprinidae · Valenciennes, 1842
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.

Barbonymus altusRed-tailed Tinfoil Barb
Cyprinidae · Günther, 1868
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 ...

Barbonymus gonionotus
Cyprinidae · Bleeker, 1849
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...

Barbonymus schwanefeldiiTinfoil barb
Cyprinidae · Bleeker, 1854
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.

Betta splendensSiamese Fighting Fish
Osphronemidae · Regan, 1910
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.

Boraras urophthalmoides
Cyprinidae · Kottelat, 1991
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...

Brachydanio albolineataPearl 'Danio'
Cyprinidae · Blyth, 1860
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...

Carinotetraodon lortetiRedeye Puffer
Tetraodontidae · Tirant, 1885
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'.

Channa gachuaDwarf Snakehead
Channidae · Hamilton, 1822
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.

Channa luciusForest Snakehead
Channidae · Cuvier, 1831
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.

Crossocheilus atrilimesSiamese Algae Eater
Cyprinidae · Kottelat, 2000
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...

Crossocheilus reticulatus
Cyprinidae · Fowler, 1934
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...

Cyclocheilichthys apogonBeardless Barb
Cyprinidae · Valenciennes, 1842
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.

Cyclocheilichthys armatus
Cyprinidae · Valenciennes, 1842
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...

Cyclocheilichthys heteronema
Cyprinidae · Bleeker, 1854
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...

Cyclocheilichthys lagleri
Cyprinidae · Sontirat, 1985
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.

Cyclocheilichthys repasson
Cyprinidae · Bleeker, 1853
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...

Datnioides polotaSilver Tiger Perch
Datnioididae · Hamilton, 1822
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.

Discherodontus halei
Cyprinidae · Duncker, 1904
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'.

Discherodontus schroederi
Cyprinidae · Smith, 1945
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...

Epalzeorhynchos bicolorRed-Tailed Black Shark
Cyprinidae · Smith, 1931
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...

Epalzeorhynchos frenatumRainbow Shark
Cyprinidae · Fowler, 1934
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...

Esomus metallicusStriped Flying Barb
Cyprinidae · Ahl, 1923
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.

Folifer brevifilis
Cyprinidae · Peters, 1881
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'.

Garra cambodgiensisFalse SAE
Cyprinidae · Tirant, 1883
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...

Gyrinocheilus aymonieriSucking 'Loach'
Gyrinocheilidae · Tirant, 1883
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.

Helostoma temminkiiKissing Gourami
Helostomatidae · Cuvier, 1829
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...

Hemimyzon nanensis
Balitoridae · Doi & Kottelat, 1998
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...

Homalopteroides smithi
Balitoridae · Hora, 1932
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...

Hypsibarbus vernayi
Cyprinidae · Norman, 1925
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.

Hypsibarbus wetmorei
Cyprinidae · Smith, 1931
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.

'Inlecypris' maetaengensisFire Bar 'Danio'
Cyprinidae · Fang, 1997
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.

Kryptopterus bicirrhis
Siluridae · Valenciennes, 1840
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.

Kryptopterus geminus
Siluridae · Ng, 2003
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...

Kryptopterus limpok
Siluridae · Bleeker, 1852
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...

Labiobarbus leptocheilus
Cyprinidae · Valenciennes, 1842
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.

Laubuka caeruleostigmataFlying Minnow
Cyprinidae · Smith, 1931
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.

Laubuka siamensis
Cyprinidae · Fowler, 1939
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...

Lepidocephalichthys berdmorei
Cobitidae · Blyth, 1860
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...

Lepidocephalichthys hasselti
Cobitidae · Valenciennes, 1846
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.

Lepidocephalichthys kranos
Cobitidae · Havird & Page, 2010
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...

Lepidocephalus macrochir
Cobitidae · Bleeker, 1854
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).

Lobocheilos melanotaenia
Cyprinidae · Fowler, 1935
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...

Lobocheilos rhabdoura
Cyprinidae · Fowler, 1934
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...

Luciosoma bleekeri
Cyprinidae · Steindachner, 1878
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.

Luciosoma setigerumApollo Shark
Cyprinidae · Valenciennes, 1842
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.

Mystacoleucus greenwayi
Cyprinidae · Pellegrin & Fang, 1940
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,...

Mystacoleucus obtusirostris
Cyprinidae · Valenciennes, 1842
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).

Nemacheilus binotatus
Nemacheilidae · Smith, 1933
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...

Nemacheilus masyaeArrow Loach
Nemacheilidae · Smith, 1933
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.

Nemacheilus pallidus
Nemacheilidae · Kottelat, 1990
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).

Opsarius infrafasciatus
Cyprinidae · Fowler, 1934
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...

Opsarius koratensis
Cyprinidae · Smith, 1931
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...

Opsarius pulchellus
Cyprinidae · Smith, 1931
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...

Oryzias minutillusDwarf Medaka
Adrianichthyidae · Smith, 1945
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.

Pangio anguillaris
Cobitidae · Vaillant, 1902
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.

Pethia stoliczkana
Cyprinidae · Day, 1871
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...

Pseudohomaloptera sexmaculata
Balitoridae · Fowler, 1934
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.

Puntigrus partipentazona
Cyprinidae · Fowler, 1934
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.

Rasbora dorsinotata
Cyprinidae · Kottelat, 1987
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...

Rhinogobius chiengmaiensisChiangmai Stream Goby
Gobiidae · Fowler, 1934
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...

Schistura geisleri
Nemacheilidae · Kottelat, 1990
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.

Schistura kohchangensisOrnate Tiger Sand Loach
Nemacheilidae · Smith, 1933
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...

Schistura pridiiMini Dragon Loach
Nemacheilidae · Vidthayanon, 2003
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.

Schistura spilota
Nemacheilidae · Fowler, 1934
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...

Syncrossus beaufortiChameleon Loach
Botiidae · Smith, 1931
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 ...

Syncrossus helodesBanded Tiger Loach
Botiidae · Sauvage, 1876
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...

Systomus orphoides
Cyprinidae · Valenciennes, 1842
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...

Trichopsis pumilaSparkling Gourami
Osphronemidae · Arnold, 1936
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.

Trichopsis schalleri
Osphronemidae · Ladiges, 1962
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'.

Trichopsis vittataCroaking gourami
Osphronemidae · Cuvier, in Cuvier & Valenciennes, 1831
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...

Xenentodon cancilaFreshwater Needlefish
Belonidae · Hamilton, 1822
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...

Yasuhikotakia leconteiSilver Loach
Botiidae · Fowler, 1937
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...

Yasuhikotakia modestaRedtail Loach
Botiidae · Bleeker, 1864
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).

Yasuhikotakia morletiSkunk Loach
Botiidae · Tirant, 1855
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...

Anabas testudineusClimbing Perch
Anabantidae · Bloch, 1792
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...

Bagarius suchusCrocodile Catfish
Sisoridae · Roberts, 1983
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).

Bagarius yarrelliGoonch
Sisoridae · Sykes, 1839
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.

Channa maruliusBullseye Snakehead
Channidae · Hamilton, 1822
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...

Channa micropeltesGiant Snakehead
Channidae · Cuvier, 1831
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...

Chitala lopisGiant Featherback
Notopteridae · Bleeker, 1851
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.

Chitala ornataClown Featherback
Notopteridae · Gray, 1831
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...

Crossocheilus cobitis
Cyprinidae · Bleeker, 1854
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.

Cyclocheilos enoplos
Cyprinidae · Bleeker, 1849
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...

Datnioides pulcherSiamese Tiger Perch
Datnioididae · Kottelat, 1998
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.

Garra fuliginosa
Cyprinidae · Fowler, 1934
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...

Hampala macrolepidotaHampala Barb
Cyprinidae · Kuhl & van Hasselt, 1823
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.

Hemibagrus spilopterus
Bagridae · Ng & Rainboth, 1999
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...

Hemibagrus wyckiiCrystal-eyed Catfish
Bagridae · Bleeker, 1858
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.

Hemibagrus wyckioidesAsian Red Tailed Catfish
Bagridae · Fang & Chaux, 1949
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...

Hypsibarbus malcolmiGoldfin Tinfoil Barb
Cyprinidae · Smith, 1945
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.

Incisilabeo behri
Cyprinidae · Fowler, 1937
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...

Labeo chrysophekadionBlack Shark
Cyprinidae · Bleeker, 1849
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...

Leptobarbus rubripinnaRed-finned Cigar Shark
Cyprinidae · Fowler, 1937
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...

Macrochirichthys macrochirusGiant Sword Minnow
Cyprinidae · Valenciennes, 1844
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.

Notopterus notopterusBronze Featherback
Notopteridae · Pallas, 1769
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.

Phalacronotus apogon
Siluridae · Bleeker, 1851
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...

Amblyrhynchichthys micracanthus
Cyprinidae · Ng & Kottelat, 2004
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'.

Channa maculataBlotched Snakehead
Channidae · Lacepède, 1801
This species is frequently confused with C. argus but can be distinguished by the following characters: dorsal-fin rays 38-45 (vs. 47-50 in C. argus); anal fin rays 26-29 (vs. 31-36); lateral line scales 50-56 (vs. 60-66); 2-3 rounded blotches on caudal peduncle (vs. no blotches on caudal peduncle). It is widely-distributed in Pacific coastal drainages of southeastern China (e.g. the Yangtze, Minjiang, Hangjiang River, and Pearl (Nanjiu...

Garra theunensis
Cyprinidae · Kottelat, 1998
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...

Gymnostomus lineatus
Cyprinidae · Smith, 1945
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'.

Gymnostomus lobatus
Cyprinidae · Smith, 1945
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.

Gymnostomus siamensisSiamese Mud Carp
Cyprinidae · Sauvage, 1881
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.

Labiobarbus siamensis
Cyprinidae · Sauvage, 1881
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...

Mystacoleucus chilopterus
Cyprinidae · Fowler, 1935
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.

Bagarius bagarius
Sisoridae · Hamilton, 1822
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.