Country · Asia
Vietnam
Every profile recorded in Vietnam, native or introduced.
- Species
- 123
- Families
- 22
- Genera
- 68
- Found only here
- 11
- Photographed
- 123 of 123
Where it isAsia
Shares its fishes withspecies recorded in both
Found only here11
11 of these profiles carry Vietnam and no other country. That is not the same as endemic. Most of these distributions are only half recorded.

Acheilognathus macropterusGiant Chinese Bitterling
Cyprinidae · Bleeker, 1871
A. macropterus appears in the ornamental trade on an irregular basis and should only be considered by more experienced aquarists with sufficiently large facilities. Given its wide geographical distribution there is a possibility that it represents a group of closely-related species, with genetic studies indicating the existence of several distinct clades.

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.
Annamia cf. thuathienensis
Gastromyzontidae · Nguyen, 2005
Annamia spp. may be confused with related genera such as those of the genus Balitoropsis. They can be identified by their more depressed body shape, elongate lower caudal-fin lobe, and the presence of a single unbranched ray in the pectoral and pelvic fins. At least one undescribed member of the genus is thought to exist.

Annamia normaniVietnamese Giraffe Loach
Gastromyzontidae · Hora, 1931
Traditionally considered to be a micropredator feeding on insect larvae and suchlike (Rainboth, 1996), but a study by Herder and Freyhof (2006) revealed adult A. normani inhabiting the Duc My River in central Vietnam to be specialised grazers of cyanobacteria. In rapids the latter form hard encrustations on rock surfaces from which adults are able to bite chunks.

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...

Barbodes aurotaeniatus
Cyprinidae · Tirant, 1885
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.

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.

Barbodes semifasciolatusGolden Barb*
Cyprinidae · Günther, 1868
This species is also known by the alternative names 'green' or 'Chinese' barb. The natural 'green' form is an infrequent find in the aquarium trade whereas the selectively-bred 'golden' variant is farmed in huge numbers and is among the most popular of freshwater aquarium fish. The latter was first produced in the 1960s and is now so ubiquitous that many hobbyists are initially unaware that it is not the natural form.

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 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 siamorientalis
Osphronemidae · Kowasupat, Panijpan, Ruenwongsa & Jeenthong, 2012
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...

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...

Butis butisCrazy Fish
Eleotridae · Hamilton, 1822
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...

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 asiaticaChinese Snakehead
Channidae · Linnaeus, 1758
No bubble nest is built and several thousand eggs simply float at the surface with both male and female remaining to defend the eggs and fry. The eggs hatch after 24-36 hours depending on temperature and the fry are free swimming in a further 24 hours. At this point they resemble 6-7 mm long black tadpoles. It is important to constantly feed...

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 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.

Datnioides undecimradiatusMekong Tiger Perch
Datnioididae · Roberts & Kottelat, 1994
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.

Esomus longimanusMekong Flying Barb
Cyprinidae · Lunel, 1881
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'.

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...

Garra fasciacauda
Cyprinidae · Fowler, 1937
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.

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...

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...

Homalopteroides tweediei
Balitoridae · Herre, 1940
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...

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.

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 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 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...

Lepidocephalichthys sp. 'LE1'Vietnamese Marbled Hog-faced Loach
Cobitidae · authority not recorded
This fish has only been traded on a handful of occasions to date. It's been referred to as Lepidocephalichthys cf. hasselti and Lepidocephalus cf. thermalis but appears to be an undescribed member of the former genus. Following a...

Lepidocephalichthys zeppelini
Cobitidae · Havird & Tangjitjaroen, 2010
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.

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.

Macropodus erythropterus
Osphronemidae · Freyhof & Herder, 2002
This species is frequently mistaken for the similar-looking congener M. spechti Schreitmüller 1936, which is easily-identified by the absence of reddish pigmentation in the dorsal, anal, and caudal fins. There has been some debate as to whether these two represent the same taxon, however, with Winstanley and Clements (2008) proposing that M. erythropterus be considered a synonym of M. spechti because they were unable to separate the two species by morphological characters, and specimens with red pigmentation on the unpaired fins were coll...

Macropodus opercularisParadise Fish
Osphronemidae · Linnaeus, 1758
M. opercularis is a classic aquarium fish, having been introduced to the hobby by a French soldier named Gerault in 1869. Of the initial 100 specimens shipped, 22 survived and were successfully bred later that same year by another Frenchman, the Parisian Pierre Carbonnier. This gives the species the distinction of being one of the very first ornamental fish imported to Europe. It is also known as 'Chinese fighting fish', 'paradise gourami', and 'blue paradise fish'.

Macropodus spechtiBlack Paradise Fish
Osphronemidae · Schreitmüller, 1936
M. spechti is also sometimes referred to as M. concolor, particularly in older literature. A dispute regarding conservation of that name was resolved by the ICZN in 2006, however, since M. concolor Ahl, 1937 is a junior primary homonym of M. concolor Schreitmüller, 1936 and thus permanently invalid.

Microcobitis misgurnoides
Cobitidae · Rendahl, 1944
This species was initially described as a member of Cobitis and remained as such for over 60 years until being redescribed in the new genus Microcobitis by Bohlen and Harant (2011). It can be separated from Cobitis species by a number of char...

Micronemacheilus cruciatus
Nemacheilidae · Rendahl, 1944
This species is traded under various names including 'Vietnamese multi-banded zebra loach', 'hovering zebra loach', 'Laos pygmy multi-stripe loach', and 'banded dwarf loach'. It can be distinguished from related species by the following combination of characters: body with distinct vertical bars; 8 branched dorsal-fin rays; 3-10 pored lateral line scales; one pair of large papillae in median portion of upper lip; two pairs of large papillae in median portion of lower lip; lower posterior edge of opercle with 3-4 prominent indentations.

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 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).

Nemacheilus platiceps
Nemacheilidae · Kottelat, 1990
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...

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 latipesMedaka
Adrianichthyidae · Temminck & Schlegel, 1846
Commonly known as 'Japanese rice fish' or simply 'rice fish', O. latipes is well-known to science having been widely used as a model organism in genomic and experimental biology for well over a century and was the first vertebrate animal to mate in space during the mid-1990s. It's also been a popular aquarium fish for many years, though is less widely-available than it once was, with the ornamental 'gold' vari...

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.

Pangio myersiGiant Kuhli Loach
Cobitidae · Harry, 1949
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...

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.

Rhinogobius giurinus
Gobiidae · Rutter, 1897
This species appears to exist in a number of different forms which exhibit differences in colour pattern, morphology, or both, and it's currently unclear whether all of them are truly conspecific or not although to avoid confusion we list all together here.

Rhinogobius leavelli
Gobiidae · Herre, 1935
This species appears to exist in a number of different forms which exhibit differences in colour pattern, morphology, or both, and it's currently unclear whether all of them are truly conspecific or not although those in the aquarium trade all appear similar to one another. We've been unable to obtain a copy of the original description so it's not currently possible to provide a detailed diagnosis either, with most recent studi...

Rhinogobius mekongianus
Gobiidae · Pellegrin & Fang, 1940
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.

Schistura callichroma
Nemacheilidae · Zhu & Wang, 1985
Type locality is given as 'Babianjiang River, 24°20'N, 100°10'E, Jingdong County, Yunnan Province, China'. The Babianjiang joins the Mengyejiang River to form the Langmajiang River, a tributary of the Lixianjiang (Black River) within the Red River basin.

Schistura laterivittata
Nemacheilidae · Zhu & Wang, 1985
It's been considered a synonym of Schistura caudofurca (Mai, 1978) by the majority of recent authors following Kottelat (2001) but this appears to be a case of misidentification since the two species exhibit several notable differences based on their respective descriptions (Endruweit, 2010).

Sewellia albisuera
Gastromyzontidae · Freyhof, 2003
It's been suggested that these two may represent the same species but this appears not to be the case. When describing S. albisuera Freyhof (2003) used a series of specimens collected in 2000 plus some larger, spotted fish which had been collected in 1999 and preserved in New York. Although he noticed differences in dorsal patterning between the two series these weren't considered sufficient to s...

Sewellia elongata
Gastromyzontidae · Roberts, 1998
This species appeared in the trade during 2010 and its identity has been confirmed to us by Thai exporter and aquarist Kamphol Udomritthiruj who collects it from the Se Kong system for the aquarium hobby. To date only subadult specimens have reached the western market.

Sewellia lineolataTiger Hillstream Loach
Gastromyzontidae · Valenciennes, 1846
S. lineolata was first recorded by Diard over 150 years prior to its 'rediscovery' in the early-1990s. It became available to the aquarium trade in the mid-2000s and swiftly established itself as one of the more popular balitorids in the hobby due to its attractive body markings and ease of breeding. It's also sold under the names 'reticulated hillstream loach', 'Vietnamese hillstream loach' and 'gold ring butterfly sucker'. It's difficult to...

Sewellia sp. 'SEW01'Spotted Butterfly Loach
Gastromyzontidae · authority not recorded
This is one of the more readily-available members of the genus and popularly referred to as S. sp. 'spotted' or S. sp. 'special'. It's superficially similar in appearance to S. albisuera but in that species body patterning consists of a network of irregular dark lines forming a complicated series of reticulations vs. many small, light spots on a dark background in S. sp. 'SEW01'. It's been suggested that these two may represent the same species but this...

Sewellia sp. 'SEW02'
Gastromyzontidae · authority not recorded
This species first became available in early 2009 and was initially identified as S. breviventralis (Freyhof and Serov, 2000) because there is a clear space between the pelvic and anal fins and body patterning is vaguely similar to that species, and also appears quite similar to S. elongata (Roberts, 1998) and S. sp. 'SEW03'. It does not fully match the original descriptions of either, however, and therefore remains in need of identification.

Sewellia sp. 'SEW03'
Gastromyzontidae · authority not recorded
This fish first became available in early 2009 and was initially identified as S. breviventralis (Freyhof and Serov, 2000). However it cannot be that species because there is no discernible gap between pelvic and anal fins, which also discounts the possibility of it being S. elongata (Roberts, 1998). It therefore remains unidentified and is often imported in mixed batches with S. sp. 'SEW02', which it also resembles closely.

Sewellia speciosa
Gastromyzontidae · Roberts, 1998
This species first became available in early 2010 and sometimes appears on trade lists under the vernacular names 'Laos sucker' or 'Laos Sakura sucker'. It's distinguishable from other members of the genus by the following combination of characters: body spotted and without stripes; no concentric bands on paired fins; origin of pelvic-fin below origin of dorsal-fin; origin of pectoral-fin posterior to corner of mouth; pelvic fin reaching origin of anal fin; small elevated ...

Sinogastromyzon tonkinensis
Balitoridae · Pellegrin & Chevey, 1935
At the type locality of the congener S. lixianjiangensis sympatric species included Balitora kwangsiensis, Glyptothorax quadriocellatus, Garra orientalis, Hemibagrus pluriradtus, Poropuntius huangchieni, Pseudecheneis paviei,...

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...

Tanichthys albonubesWhite Cloud Mountain Minnow
Cyprinidae · Lin, 1932
One of the most ubiquitous species in the hobby and several ornamental strains are available including 'long-finned', 'golden', 'albino', and 'super red', for which care is identical to that of the 'standard' fish. Unfortunately the degree of inbreeding amongst farm-bred stock has resulted in a situation whereby many of the fish available today are genetically weak and prone to disease or develop physical deformities.

Tanichthys micagemmae
Cyprinidae · Freyhof & Herder, 2001
This species only became available in the aquarium hobby during the early 21st century but has already achieved a measure of popularity since it's attractive, easy to maintain and usually quite cheaply-priced. You may see it on sale under various trade names including 'Vietnamese minnow', 'cardinal minnow', 'royal white cloud', 'dwarf cardinal' and others. We've obtained images of what is said to be a naturally-occurring form with extremely elong...

Tanichthys sp. 'Vietnam'
Cyprinidae · authority not recorded
This fish was first collected in 2009 and limited numbers have been available in the aquarium trade. Though additional exports may be unlikely it's proven easy to breed in captivity and there's a fair chance it will become established in the hobby. It's sold under several names including T. sp. 'lemon' or 'yellow white cloud', and has also been misidentified as the congener T. thacbaensis, a valid species occurring much further north in Vietnam.

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 canciloides
Belonidae · Bleeker, 1854
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...

Yasuhikotakia eosSun Loach
Botiidae · Taki, 1972
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...

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 rutilus
Sisoridae · Ng & Kottelat, 2000
Known from the from the Red River in northern Vietnam and Yunnan province, southern China, plus the Thái Bình, Sông Kỳ Cùng, Mã and Lam rivers in Vietnam and possibly the Nam Xam and Nam Ma drainages in Laos. Type locality is 'Market in Hanoi, Vietnam'.

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.

Brachygobius aggregatusSchooling Bumblebee Goby
Gobiidae · Herre, 1940
Though this species appears on ornamental trade lists quite often the name appears to be routinely misapplied to other species, particularly B. doriae. It can be diagnosed as follows: <30 lateral scales; two black body bands reaching ventral midline posterior to anal-fin; band above anal-fin als...

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 blanciRoyal Featherback
Notopteridae · d'Aubenton, 1965
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.

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...

Ctenopharyngodon idellaGrass Carp
Cyprinidae · Valenciennes, 1844
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.

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...

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.

Mekongina erythrospila
Cyprinidae · Fowler, 1937
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'.

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...

Scleropages formosusAsian Arowana
Osteoglossidae · Müller & Schlegel, 1840
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...

Acrossocheilus iridescens
Cyprinidae · Nichols & Pope, 1927
A. iridescens and its closest relative A. longipinnis can be distinguished from all other barred species of Acrossocheilus by the following characters: wider (vs. narrower) black vertical bars on the flank in adults, each five to eight (vs. no more than four) scales in width; a horse-shoe shaped (vs. arched) mouth gape; rostral barbel located posteriorly (vs. anteriorly) to a horizontal line through the anteriormost margin of the lower jaw; two postlabial grooves extending anteromedially beyond (vs. away from) a horizontal line through the roots of the rostral barbels.

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...

Elopichthys bambusa
Cyprinidae · Richardson, 1845
The adult size and power of this impressive predator preclude it from consideration as an aquarium species, but young individuals are nevertheless available in the ornamental trade on an irregular basis therefore it is included here. It is an entirely unsuitable choice for the home aquarium and the majority of zoos and public aquaria would probably struggle to maintain it in adequate conditions.

Garra imberba
Cyprinidae · Garman, 1912
This species can be distinguished from congeners inhabiting the Red River basin in Yunnan province, China, by the following combination of characters: no barbels; 46-52 lateral line scales; 16 circumpeduncular scales; pharyngeal teeth in 3 rows, 2.4.5-5.4.2; snout rounded, no secondary rostrum, no longitudinal...

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.

Hypsibarbus pierreiYellow Eyed Silver Barb
Cyprinidae · Sauvage, 1880
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.

Labeo pierrei
Cyprinidae · Sauvage, 1880
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.

Metzia formosae
Cyprinidae · Oshima, 1920
Although it is included in the genus Metzia this grouping remains somewhat unresolved in terms of taxonomy and it may contain more than a single genetic lineage. For example, members share a number of characters with the genera Ischikauia Jordan and Snyder 1900, Hemiculterella Warpachowski 1887, and several species of Anabarilius Cockerell 1923, including a bipartite gas bladder, a non-spinous dorsal-fin ray, and a sharp ventral keel between the pelvic-fin insertion and anus.

Metzia lineata
Cyprinidae · Pellegrin, 1907
Populations from the upper Pearl River (Nanpan Jiang basin) differ in several morphological characters from those inhabiting Guangdong, Guangxi, and Guizhou Provinces, and Hainan Island. Those from Vietnam also seem to be different (Gan et al., 2009), the implication being that there may be several species currently included under the name M. lineata.