Danios & relatives

The neon hatchet fish, Chela cachius, is a deep-bodied cyprinid mostly recorded from the Ganges and Brahmaputra systems of India and Bangladesh. Its extremely deep body means it is unlikely to be confused with any related species, and it is the only valid member of the genus. A habitat generalist, it is an active schooling fish that is best kept in a group of at least 8-10 in a tank with a tightly-fitting cover, since it is an accomplished jumper.

The panther danio, Danio aesculapii, is a small cyprinid endemic to the Rakhine Yoma (Arakan mountains) of western Myanmar. It continues to be traded under names such as 'Danio sp. pantheri', 'D. sp. hieroglyph' and 'D. sp. TW03'. Six or seven brown vertical bars on the front of the body and two rows of small brown spots behind them set it apart from congeners. One of the smaller members of the genus at 25 to 30 mm, it inhabits seasonal streams and pools.

The pearl danio, Danio albolineatus, is a small cyprinid recorded from Myanmar and Indochina south to Peninsular Malaysia and Sumatra. Colour and patterning differ between localities, and doubts remain whether it is a single species or a group of closely related fish. Wild examples are rare in the trade, with most produced commercially in South East Asia or eastern Europe, and some of the fish traded are likely to be hybrids with D. roseus.

The glowlight danio, Danio choprae, is a small cyprinid from northern Myanmar, apparently restricted to the Mogaung Chaung system. Available in the trade since around 2003, it quickly became one of the most popular small danionins in the hobby, and commercial breeding means wild fish are hard to come by. It closely resembles D. flagrans, and the spelling 'choprai' seen in some sources is not the accepted one.

The northern glowlight danio, Danio flagrans, is a small cyprinid known only from a handful of streams near Putao in far northern Myanmar. It has reached the hobby in limited numbers, also traded as 'Danio sp. Putao', 'D. putaoensis' or 'D. cf. choprae'. It looks very similar to D. choprae and is told apart by its more slender body, longer barbels and an almost always present lateral line.

Danio jaintianensis is a small cyprinid known only from the Jaintia Hills of Meghalaya, in the Brahmaputra system of northeastern India. It is likely to be restricted to small, slower-moving hill streams with gravel and rocky substrates and thick marginal vegetation. It is best kept in an unheated tank and tends to struggle above 25 °C for long periods. Its temperature needs and rarity make it hard to recommend for the general community.

The blue danio, Danio kerri, is a small cyprinid from islands and the adjacent mainland of south-western Thailand. It was described from Phang Nga province and has since been recorded from Phuket, Ko Lanta, Langkawi, Krabi and Ranong. Base body colour is powdery-blue in the north of its range and more yellowish in the south, with pinkish-yellow lateral stripes. It inhabits clear forest streams over rocks and gravel, and can be hard to find in aquarium shops.

The celestial pearl danio, Danio margaritatus, is a miniature cyprinid from the Salween drainage in Shan State, eastern Myanmar. First marketed as 'Galaxy Rasbora' after its discovery in 2006, it became one of the most hyped fishes the hobby has known, and Myanmar banned exports in 2007 after reports of overfishing. Intensive commercial breeding means specimens with spotted fins or deformities are now common in the ornamental trade.

The dwarf spotted danio, Danio nigrofasciatus, is a small cyprinid endemic to central Myanmar, on both sides of the Bago Yoma range. It inhabits streams, minor rivers, ponds, ditches and rice paddies, many of them seasonal. A spotted anal-fin separates it most easily from similar species such as D. rerio and D. kyathit. Very peaceful but rather timid, it does best alone or with similarly sized species that enjoy similar conditions.

The zebra danio, Danio rerio, is a small cyprinid from India and Bangladesh, found mostly in slow or still pools and mature rice paddies. Peaceful, hardy and inexpensive, it has been mass-produced for many years and quality stock can be hard to find. The spotted 'leopard danio' is a spontaneous mutation of the striped form that also occurs in the wild.

The rosy danio, Danio roseus, is a small cyprinid from the Mekong basin in northern Thailand and Laos, also recorded in northern Myanmar. Colourful, hardy and usually cheap, it has proved very popular and is sometimes sold as 'purple passion danio'. It is very similar to D. albolineatus sensu stricto but has a slimmer body, shorter rostral barbels and no dark stripes on the rear half of the body. Many fish in the hobby are thought to be hybrids of the two.

The hikari danio, Danio sp. 'hikari', is a probable undescribed cyprinid from the Tanintharyi River drainage in southern Myanmar. First available in 2002, males and females were sold as 'Danio sp. hikari yellow' and 'D. sp. hikari blue'. DNA testing showed them to be one species, distinct from the very similar D. kerri, in which the central body stripe ends at the caudal peduncle. Only one population of D. kerri was sampled, so it could still be a colourful form of that species.

The black-barred danio, Danio sp. 'TW01', is a cyprinid apparently discovered near the coastal town of Gwa in Rakhine State, western Myanmar. It remains unclear whether it is an undescribed species or a geographical form of D. feegradei, which it resembles apart from lacking pale spots on the body. A dark marking on the caudal peduncle separates it from the superficially similar 'Inlecypris' maetaengensis and 'I.' shanensis.

The gold ring danio, Danio tinwini, is a tiny cyprinid from the Mogaung Chaung, an Irrawaddy tributary in Kachin State, northern Myanmar. Seen in the trade since 2003, it has been sold as 'Danio sp. TW02', 'D. sp. fire ring', 'D. sp. gold ring' and 'D. sp. spotted', among other names. Smaller than the similar D. kyathit and D. nigrofasciatus, it has spotted unpaired fins and much shorter barbels. Adults measure just 20 to 30 mm, so tankmates need choosing with that in mind.

Inlecypris auropurpurea is a cyprinid known only from Lake Inlé and its surrounding watershed in Shan state, eastern Myanmar. It is listed as 'Endangered' on the IUCN Red List after a significant decline, as farming around the lake has increased sedimentation, eutrophication and pollution. A peaceful schooling fish, it suits a densely planted tank with a tightly fitting cover, since it is a particularly accomplished jumper.

Microdevario gatesi is a miniature cyprinid from the lower Irrawaddy basin in Myanmar, growing to around 23 mm SL. Uncommon in the aquarium hobby, it is sometimes traded as 'Burmese golden rasbora' and can be told from its congeners by its hyaline dorsal and anal fins. It is likely to inhabit sluggish and standing waters such as rice paddies, swamps and weedy ditches, and is possibly endemic to the Irrawaddy Delta.

Microdevario nanus is a miniature cyprinid from the lower Sittaung and Bago drainages of the Irrawaddy system in Myanmar. Sometimes referred to as 'green dwarf rasbora' or 'nana rasbora' in the ornamental trade, it grows to around 16 mm SL. A black blotch at the tip of the dorsal fin and a greyish marking at the tip of the anal fin immediately distinguish it from congeners.

The flame red 'rasbora', Microrasbora cf. rubescens, is a small cyprinid from Shan State in eastern Myanmar. Possibly an undescribed species, it has been marketed as 'Asian Cardinal Rasbora', M. sp. 'rose blue line' or M. 'thuzari'. It differs from M. rubescens in its larger adult size, a greenish to bluish lateral stripe and less orange on the body, and appears to represent a distinct genetic lineage.

The red dwarf 'rasbora', Microrasbora rubescens, is a small cyprinid endemic to Lake Inle and its watershed in Shan State, eastern Myanmar. It is listed as 'Endangered' on the IUCN Red List after a significant decline in the wild, as sedimentation, eutrophication, pollution and introduced predatory Parambassis and Tilapia have degraded the lake. It may also be sold as 'red-line dwarf rasbora' or 'emerald dwarf rasbora'.

The dadio, Laubuka dadiburjori, is a small cyprinid endemic to southern India, recorded from Goa, Karnataka, Kerala and Tamil Nadu. It has also been marketed as 'Burjor's brilliance', 'orange chela' and 'orange hatchetfish', and does not exceed 30 mm SL. A dark bluish stripe runs from the eye to the caudal peduncle, typically forming 2-5 round spots. There is a suggestion that it is not a direct relative of other Laubuka and may warrant its own genus.

Devario sp. 'purple cypris' is a small, unidentified devario that has appeared in the aquarium trade only on a handful of occasions. It has been widely misidentified as Inlecypris jayarami, but has 9 or 10 lateral bars that increase in size towards the tail, 12 anal-fin rays and a blunter head.

The princess carplet, Amblypharyngodon chulabhornae, is a small cyprinid from Thailand and the Mekong system in Laos, Vietnam and Cambodia. It favours wetlands and marginal zones with little water movement and plenty of aquatic and floating vegetation,. Almost unknown in the hobby, it turns up as occasional bycatch among shipments of other fishes. A very peaceful schooling fish, it should be kept in a group of at least 8 to 10.

Betadevario ramachandrani is a danionin cyprinid known only from two sites in the upper Sita River drainage near Agumbe, Karnataka, India. Agumbe lies in heavily forested country in the Western Ghats and is among the rainiest places in India. An active species, it suits a tank set up like a flowing stream at 18 to 23 °C, and its constant movement and vigorous feeding can stress less active tankmates.

The moustached danio, Danio dangila, is a cyprinid from the Ganges and Brahmaputra drainages, with most records from Nepal, India and Bangladesh. The common name refers to its exceptionally long barbels, and despite its apparent abundance in nature it remains uncommon in the hobby. Its constant activity can upset slow-moving or timid tankmates, so it suits larger tanks with similarly-sized fishes, and adult size appears to vary by population from 60 to 130 mm.

Danio erythromicron is a miniature danionin from Lake Inle and its surrounding watershed in Shan State, eastern Myanmar. Fully grown at just 20 mm, it is sold under trade names including 'emerald dwarf danio' and 'cross-banded dwarf rasbora'. It will not do well in acidic water, and there is limited evidence that it has been hybridised with D. margaritatus and the offspring sold as females of that species.

The Yoma danio, Danio feegradei, is a cyprinid considered endemic to the western slopes of the Rakhine Yoma in western Myanmar. Seen in the hobby since around 2005, it is traded under names such as 'Danio sp. Yoma', 'D. sp. gold laser' and 'D. sp. rocket'. The spot-like markings on the flanks vary, and some specimens lack them entirely. It inhabits small, seasonal forest streams, and its constant activity suits it to larger tanks with similarly sized fishes.

The orange-finned danio, Danio kyathit, is a small cyprinid from the upper Irrawaddy (Ayeyarwady) River drainage in northern Myanmar. Its body patterning varies, with the lateral stripes solid in some specimens and wavy or broken into spots in others, and the striped form was recovered as genetically distinct from the spotted one. Striped fish resemble D. rerio but have much longer barbels and red to orange fins. Very peaceful, it seems most comfortable at 16 to 26 °C.

Much of Meghalaya consists of forested hills which receive a great deal of rainfall and many of its waters flow swiftly. This species typically inhabits high elevation (> 1000 m amsl) streams running over rocky, boulder-strewn substrates with few aquatic plants, although at some localities the flow may be more sluggish with riparian vegetation providing shade.

Danionella dracula is a miniature cyprinid known only from the Mogaung Chaung, a tributary of the Ayeyarwady in Kachin State, northern Myanmar. Males carry a row of tooth-like processes in the jaws ending in a large fang-like pair, a structure unique among cypriniform fishes according to current knowledge. It grows to around 17 mm SL, has been sold as Danionella sp. 'neon green', and is best kept alone in a school of a dozen or more.

Danionella priapus is a miniature cyprinid known only from the Jorai River, a Sankosh tributary in the Brahmaputra drainage of West Bengal, India. Males have a conical projection of the genital papilla forming a funnel between the pelvic fins, a feature that may be unique within the Cypriniformes. Referred to as D. sp. 'Jorai River' before its description, it grows to 16 mm SL and was collected from a sluggish, densely vegetated stream alongside Dario dario.

Danionella translucida is a miniature, almost transparent cyprinid from a handful of streams draining the Bago Yoma range in Myanmar. Adults measure only 9 to 11 mm SL, and it has been referred to as 'micro glassfish' in the ornamental trade. It inhabits wide, low-altitude streams with turbid water, and it is best kept alone in a school of a dozen or more.

Devario acrostomus is a devario from the Nam Leuk drainage in Vientiane Province, Laos, and has also been recorded in northeastern Thailand. It first appeared in the hobby in early 2011. It looks like D. aequipinnatus and allies at first glance, but has a sharp, upwardly-pointing mouth, a snout longer than the eye diameter, long rostral barbels and strongly pigmented body patterning. Above Tad Leuk falls its habitats have clear water under forest cover.

Devario acuticephalus is a small devario from Manipur state in northeastern India, also known from neighbouring Nagaland. It is rare in the hobby but traded on occasion. D. apogon from Yunnan, China, is very similar but has dark vertical bars on the front of the flanks. During a 2010 IUCN assessment it was recorded from only a handful of localities, and it is likely restricted to small hill streams.

Devario aequipinnatus is a striped devario from hill streams in northeastern India, Bangladesh and Nepal. It is recognised by three straight dark stripes along each side, of which the middle one is widest. The name was long applied to almost any striped Devario, including the commercially bred giant danio, which is covered here under D. malabaricus.

Devario apogon is a small devario from southwestern Yunnan, China, where all known localities lie in the Daying river watershed. Narrow, indistinct vertical bars on the front of the flank, a wide, tapering P stripe behind them, and no barbels or lateral line separate it from similar congeners. It is apparently abundant in rivers, streams and even ditches, in clear or turbid water.

Devario assamensis is a deep-bodied devario from Assam and West Bengal in northeastern India, in tributaries of the lower Brahmaputra. It has been traded as Devario sp. 'Mirik red', D. sp. 'redline' and D. sp. 'blood stripe', but is very rare in the hobby. If the distribution records are correct, it occurs from around 250 m AMSL in Darrang to 1767 m at Mirik, and possibly higher in Bhutan.

Devario chrysotaeniatus is a devario from the upper Mekong watershed in Yunnan, southwestern China, northern Laos and northern Thailand. It first appeared in the hobby in 2005 and is rarely seen, probably because its natural waters lie outside the range of most commercial collectors. Its flank pattern is indistinct: a few short, thin horizontal stripes, a dark stripe along the back and a spot behind the gill opening.

The Bengal danio, Devario devario, is a devario from the Ganges and Brahmaputra river systems in northern India, Nepal and Bangladesh. Also known as the 'Sind danio', it is told apart from congeners by a single, interrupted lateral stripe on each flank. It is relatively common in the trade and produced commercially, with an albino form and a short-bodied variant sometimes sold as D. sp. 'mini Putao'.

Devario interruptus is a devario from the Hotha valley and nearby areas of southwestern Yunnan, China, close to the border with Myanmar. Short, wide vertical bars on the flanks and a P stripe made of contiguous dark blotches separate it from the similar D. maetaengensis and D. shanensis. It has mostly been collected from small, clear, moderate to swiftly-flowing streams over sand, gravel and rocks with no aquatic vegetation.

Devario laoensis is a devario from the upper Mekong watershed in northwestern Laos and northern Thailand. Its dark P stripe starts faint around mid-body and becomes thicker and darker towards the caudal-fin base. Among congeners it is most similar to D. chrysotaeniatus, in which the P stripe extends to the end of the caudal-fin rays. Its habitats lie at relatively high altitude and are likely to be hill streams and small rivers.

The giant 'danio', Devario malabaricus, is a deep-bodied devario from peninsular India, living in hill streams and upper parts of small rivers. Most older aquarium literature labels it D. aequipinnatus, but genetic and morphological data have shown the traded fish to be D. malabaricus. It has a blue-and-yellow colour pattern and a P stripe extending to the fork of the caudal-fin. Its true range is uncertain and may be confined to western-flowing drainages of India.

The peninsular 'danio', Devario neilgherriensis, appears endemic to tributaries of the Bhavani river system in the Nilgiri Hills, southern India. It is almost unheard of in the trade and little is known about it. Day described it with silvery flanks and a broad, indistinct steel-blue stripe bounded above and below by a narrow bright yellow band. Several of its hill-stream habitats lie around 2000 m AMSL.

The barred 'danio', Devario pathirana, is a devario known only from a few small streams in the Nilwala River watershed of southwestern Sri Lanka. It has 7 to 11 dark blue, irregular vertical bars on the front of each flank and a short horizontal stripe on the caudal peduncle. Although endangered in nature, it is bred commercially in limited numbers and is sometimes sold as the 'tiger' or 'Ceylon' danio.

The queen 'danio', Devario regina, is a deep-bodied devario probably restricted to western and southern Thailand and northern Peninsular Malaysia. It belongs to a group of similar-looking congeners with a blue-and-yellow colour pattern. Most commonly it inhabits submontane hill streams and upper parts of small rivers with clear, well-oxygenated water.

Sometimes called the 'Hora danio' or 'Salween danio', Inlecypris shanensis is a small cyprinid from Shan state, Myanmar. Known from the Duthawadi and Salween river systems, it is most easily confused with 'I.' maetaengensis and Devario interruptus, and differs in having a P stripe that is not broken into a series of blotches. It has been collected from fast-flowing streams with clear water and substrates of rocks, pebbles and sand.

The fireline devario, Devario sondhii, is a small devario from southern Shan State, Myanmar, described from a spring near Hopong. It first appeared in the trade in the mid-2000s and was initially confused with the sympatric Microrasbora cf. rubescens and with D. acuticephalus, but a dark cleithral spot behind the gill opening separates it from both. The habitat near Hopong is shallow, permanently-flooded grassland at around 1,040 metres AMSL with dense aquatic plants.

Devario sp. 'giraffe' is an unidentified devario from Myanmar, first collected in 2007, about which very little is known. Its name refers to a giraffe-like colour pattern, with the stripes broken up towards the front of the body into spots, rings and vertical bars. It has a deep, bulky body.

The blue moon 'danio', Devario xyrops, is a devario known only from small streams draining the western slope of the Rakhine Yoma in western Myanmar. Before its description it was sometimes called D. sp. 'broken line'. A dark blotch of 4 or 5 short vertical bars on the front of the flank and a wide dark P stripe behind it are shared only with D. anomalus, which has a shallower body and more lateral line scales.

The flying minnow, Laubuka caeruleostigmata, is a cyprinid from the Mekong system in Laos, Thailand and Cambodia, and the Chao Phraya and Mae Klong. Also known as 'leaping barb', it was once quite common in the ornamental trade and has apparently become scarce in the wild. It schools near the surface in main river channels, has a bright blue spot on top of the head, and is an accomplished jumper that needs a tightly-fitting cover.

The Indian glass barb, Laubuka laubuca, is a cyprinid probably endemic to the Ganges-Brahmaputra system in northern India, Bangladesh and Nepal. Traditionally considered to occur across the Indian subcontinent and most of Southeast Asia, it appears to be far more restricted, and many fish in the trade are probably L. siamensis. L. laubuca has a roundish, ocellated humeral spot and a thin, less conspicuous stripe interrupted by vertical markings. Other names include 'Indian hatchet fish' and 'winged danio'.

Laubuka siamensis is a cyprinid from the Mekong, the Chao Phraya and Mae Klong in Thailand, and smaller drainages south to Peninsular Malaysia. Long considered synonymous with L. laubuca, it seems likely to be the species behind many of the fish entering the trade under that name. A conspicuous dark stripe, iridescent blue in life, runs uninterrupted along the rear of the body to an oval blotch on the caudal peduncle. It swims in groups at or just below the surface and is an accomplished jumper.

Microdevario kubotai is a miniature cyprinid from peninsular Thailand and the Salween drainage in southern Myanmar. Relatively common in the ornamental trade, it is sold under names including 'green neon rasbora' and 'yellow neon rasbora'. It apparently inhabits calm to moderately-flowing, well-oxygenated headwaters and minor tributaries. In nature it typically occurs in groups of 20-50, and at least 8-10 are recommended.

Devario affinis is a poorly-known devario described from 'Tenasserim', the part of Myanmar south and east of the Irrawaddy delta. It was considered a synonym of D. aequipinnatus for a period and was revalidated by Fang in 2001. Little diagnostic detail exists beyond Blyth's description of 1860. It is likely restricted to hill streams and upper parts of small rivers with clear, well-oxygenated water.

Sundadanio axelrodi is a miniature cyprinid from Borneo, where it inhabits black water streams and pools associated with forest peat swamps. Originally described as Rasbora axelrodi, it is the only member of its genus. Several colour forms exist depending on locality, normally labelled 'red', 'green' or 'blue', and they are best not mixed. Very peaceful but timid, it does best alone or with similarly sized species, in a group of at least 20-30.

Nematabramis alestes is a cyprinid from the southern Philippines, with records from Basilan, Mindanao, Palawan and Busuanga. The only member of the genus with barbels shorter than the head, its body has a pronounced ventral keel.

Nematabramis borneensis is a cyprinid endemic to the Malaysian state of Sabah in northern Borneo. It looks particularly similar to N. alestes, sharing a dark lateral stripe, but is told apart immediately by its barbels, which are longer than the head.

Nematabramis everetti is a cyprinid endemic to Borneo, known from Sarawak and Sabah plus East and North Kalimantan. It has a distinctive dark, vertically-elongate humeral marking, more prominent than in other Nematabramis species. Juveniles and subadults appear to favour fast-moving water, while adults are found in deeper, slower stretches of minor tributaries.

Nematabramis steindachnerii is a cyprinid endemic to northern and central Borneo, in Sarawak, Sabah, Brunei and North and East Kalimantan. It has barbels longer than the head but not reaching beyond the pectoral-fin base, and a relatively slender body with a short head.