River
Rajang
31 profiles across 13 families name the Rajang as a locality.
- Species
- 31
- Families
- 13
- Photographed
- 31 of 31
- Difficulty rated
- 31 of 31
Basin
Shares fishes withspecies recorded from both
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Acrochordonichthys rugosusAsian Banjo Catfish
Akysidae · Bleeker, 1846
This is the most commonly-encountered representative of the genus in the aquatic trade though is by no means common. As in other members of the genus body colouration is highly variable, even among individuals collected from a single locality, although a few useful regularities have been observed which can be used to distinguish certain species. This is thought related to the fact that Acrochordonichthys spp. periodically shed their skins and appear paler post-moulting. A. rugosus lends its ...

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.

Carinotetraodon borneensis
Tetraodontidae · Regan, 1903
This species is relatively uncommon in the aquarium hobby but is available on occasion, sometimes mixed in among shipments of the congener C. salivator. These two can be told apart by the fact that C. salivator possesses a series of distinct dark bars on the head and body in both sexes, a colour pattern unique within the genus. It is also similar t...

Carinotetraodon salivator
Tetraodontidae · Lim & Kottelat, 1995
It is included in a group often referred to as 'red-eyed puffers', which currently contains four recognised species distributed in Indochina and the Greater Sunda Islands. It can be distinguished from C. borneensis, C. irrubesco, and C. lorteti, the remaining members of this group, by the following combination of characters: 11 dorsal-fin rays; 16 pectoral-fin rays; 11-13 anal-fin rays; 11 caudal-fin rays; eyes not bulging above the head; in males dorsal-fin hyaline, black spot on dorsal-fin base present, pectoral-fin base hyaline, anal-fin hyaline with no black spot at base...

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.

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...

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.

Homaloptera orthogoniataSaddle-back Loach
Balitoridae · Vaillant, 1902
This species appears is rare in the aquarium hobby with the majority of images both online and in the published literature instead depicting H. confuzona or H. parclitella. All three are members of the H. ocellata 'group' within the genus which currently contains H. ocellata, H. bilineata, H. confuzona, H. orthogoniata, H. ogilviei and H. parclitella. Following Tan and Ng (2005) these share possession of...

Homalopteroides nebulosus
Balitoridae · Alfred, 1969
The genus Homalopteroides was revalidated by Randall and Page (2012) and is told apart from the related Homaloptera by the following character combination: dorsal-fin origin above pelvic-fin; ≤ 60 lateral-line scales; ≤ 30 predorsal scales; oral morphology consisting of two thin and widely separated rostral barbels on each side of the mouth, thin crescent-shaped lips, the absence of any structure such as a mental pad or lobes between the lateral portions of the lower lip, and a chin that extends anterior to the lateral portions of the lower lip.

Homalopteroides stephensoni
Balitoridae · Hora, 1932
Tan (2009) redescribed H. stephensoni and it possesses the following unique character set: sub-inferior mouth with thin barbels; five principle, 12-13 secondary pectoral fin rays (usually 12); scaleless belly; pattern of keeled scales on anterior, dorsal portion of body consisting of a single central keel in the posterior third of each scale; 43-50 lateral line...

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 cryptopterusBlue Sheatfish
Siluridae · Bleeker, 1851
Known from the Malay Peninsula and Singapore plus Greater Sunda Islands of Sumatra, Borneo and Java in Indonesia with populati0ns from Thailand, Cambodia, Laos and Vietnam formerly considered as conspecific now referred to K. geminus (Ng, 2003). Type locality is given as 'Bandjarmassing' which corresponds to a town now more commonly referred to as 'Banjarmasin' in South Kalimantan (Kalimantan Selatan) province, Indonesia (Borneo).

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...

Kryptopterus macrocephalusStriped Glass Catfish
Siluridae · Bleeker, 1858
Has been recorded in fast-flowing environments but most commonly associated with peat swamp forests and associated blackwater streams. Many such habitats have suffered degradation of some kind but in unaltered cases the dense canopy of branches above means very little light penetrates the surface of such environments, and riparian vegetation also tends to grow thickly.

Nemacheilus saravacensis
Nemacheilidae · Boulenger, 1894
Images depict clear, tea-coloured forest streams with dense marginal vegetation and substrates of sand and/or small rocks and pebbles. It's also known from environments with sandy substrate and organic debris in the form of submerged roots/branches and le...

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 piperata
Cobitidae · Kottelat & Lim, 1993
Some Sumatran and Bornean populations of the highly variable P. shelfordii superficially resemble P. piperata which can cause issues with identification as the two often occur together. In general however the body patterning in P. piperata is than that of P. shelfordii and they differ in vertebral counts (mode 47 vs. 50, respectively).

Pangio semicincta'Kuhli' Loach
Cobitidae · Fraser-Brunner, 1940
This species is among the most frequently-misidentified in the hobby, almost always being traded as P. kuhlii. However the latter is currently considered endemic to Java, from where commercial collections are almost unheard of, and has possibly never been seen in aquaria.

Parosphromenus allani
Osphronemidae · Brown, 1987
Type locality is given only as 'Sarawak state, Borneo, East Malaysia', with the material deriving from Sibu Division in western Sarawak. It's since been recorded at other localities within Sarawak, to which it appears endemic, but it remains unclear whether all represent a single species or not with those from the area around Lundu in northwestern Kuching Division in par...

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...

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...

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 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.

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.

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...

Sundasalanx microps
Sundasalangidae · Roberts, 1981
The genus Sundasalanx is distributed throughout much of Southeast Asia and currently comprises seven species which have primarily been distinguished on the basis of oral and dental morphology, gill rakers and eye size. S. microps possesses 0-3 small conical teeth on ceratobranchial 5, 0-2 minute gill rakers on the first arch and a small eye measuring less...

Hampala bimaculata
Cyprinidae · Popta, 1905
Predominantly a riverine fish preferring clear, well-oxygenated, running waters with substrates of sand, gravel, rock or mud, typically flowing through tropical forest. In the habitat seen in our images sympatric fish species included Barbonymus balleroides, B. collingwoodi, Cyclocheilichthys repasson, C. apogon, Diplocheilichthys pleurotaenia, Garra borneensis, Leptobarbus hosii, and an unidentified Gastromyzon sp.

Nematabramis steindachnerii
Cyprinidae · Popta, 1905
Endemic to northern and central Borneo, with records from the Malaysian states of Sarawak and Sabah, Brunei Darussalam, and the Indonesian provinces North Kalimantan (Kalimantan Utara) and East Kalimantan (Kalimantan Timur). Type locality is 'Kajan River, eastern slope of central Kalimantan, Indonesia [Borneo]'.