Pethia

Pethia aurea is a small cyprinid known from ponds in South 24 Parganas District, West Bengal, in the Ganges delta of northern India. Considered a phenotype of the similar P. gelius before its description, it has a yellowish-golden body, a broad black band around the caudal peduncle and a black blotch beneath the dorsal-fin origin. Very peaceful but timid, it does best in a group of at least 8-10 alongside other diminutive species.

Pethia canius is a small cyprinid from West Bengal in northern India, with recent collections from Cooch Behar and Nadia districts. Long considered a synonym of the closely related P. gelius, it had its identity settled and a neotype designated by Knight (2013). It inhabits ponds and other still-to-sluggish waters, and its small size and timid nature mean it does best alone or with other diminutive species.

The rosy barb, Pethia conchonius, is a small cyprinid found from Pakistan throughout India, Nepal and Bangladesh. Generally considered one of the hardiest small cyprinids in the hobby, it is an excellent choice for newcomers. Wild specimens are not usually available and the vast majority are commercially bred, with long-finned, 'veil-tail', 'super red', 'neon' and 'golden' strains among the forms selective breeding has produced. Feral populations exist in several countries.

Cuming's barb, Pethia cumingii, is a small cyprinid endemic to southwestern Sri Lanka, apparently only in the Bentara and Gin river drainages. It was long thought to occur in yellow- and red-finned forms, and the red-finned fish are now recognised as P. reval, a smaller species of sluggish lowland rivers. Reports suggest the more brightly-coloured fish are becoming scarcer, and selective collection for the aquarium trade may have altered wild populations.

Pethia didi is a small cyprinid from the Ayeyarwady drainage around Lake Indawgyi and Myitkyina, Kachin State, where it appears to be endemic. Rare in the aquarium trade though occasionally available, it has two black, vertically-orientated flank blotches, one behind the operculum and one on the caudal peduncle, a pattern shared with several congeners. The type locality is a swift, shaded stream through bamboo forest, and the species is subject to seasonal temperature fluctuations in nature.

The lipstick barb, Pethia erythromycter, is a small cyprinid from the upper Ayeyarwady River basin in northern Myanmar, including Lake Indawgyi. Sometimes traded as 'Tulip barb', it first appeared in the hobby in 2006 and was described by Kullander (2008). Males have red pigmentation around the mouth and tubercules on the snout when nuptial. It may nip slow-moving or long-finned tankmates but does very well with other small, active cyprinids or nemacheilid loaches.

The golden dwarf barb, Pethia gelius, is a small cyprinid native to the Ganges and Brahmaputra river drainages of northern India and Bangladesh. Records suggest a wider range, including Tamil Nadu and the Ayeyarwady delta in Myanmar, though the latter may warrant investigation. Knight (2013) settled its identity, revalidating P. canius and describing P. aurea, both previously treated as phenotypes of P. gelius. Very peaceful but timid, it does best alone or with other diminutive species.

The glass barb, Pethia guganio, is a small cyprinid widespread in the Ganges and Brahmaputra river systems of Bangladesh, Nepal and northern India. It lives in slow-moving or standing waters such as pools, ditches and minor rivers. Poorly known in the hobby, it shares its stiff, serrated last dorsal-fin ray, incomplete lateral line and 36-39 lateral scales only with Puntius nangalensis.

Pethia manipurensis is a small cyprinid apparently endemic to Loktak Lake in Bishnupur District, Manipur state, northeastern India. The species is considered endangered with a declining population trend, though it is bred commercially for the aquarium hobby. Males carry orange-red pigmentation on the flanks and caudal fin, as in P. meingangbii and P. padamya, but its humeral marking is a small spot where both of those have a large, vertically-elongated one.

Pethia nigripinnis is a small cyprinid of cool, flowing hill streams in Kerala and Tamil Nadu, apparently endemic to the southern Western Ghats. Adult males have black dorsal, anal, pelvic and pectoral fins. Its need for cooler temperatures makes it unlikely to suit the general community aquarium, and it will probably do best alone or with comparably-sized species needing similar conditions.

The black ruby barb, Pethia nigrofasciata, is a small cyprinid endemic to the Kelani and Nilwala river basins in the 'wet zone' of Sri Lanka. Sometimes traded as 'purple-headed barb' or 'ruby barb', it has three dark, vertical flank markings, and in spawning males the head and front of the body turn reddish-purple. Farm-raised fish are fairly adaptable in water chemistry, while wild stock are likely to prefer slightly acidic to neutral conditions.

The Odessa barb, Pethia padamya, is a small cyprinid from central Myanmar, also recorded from the lower Chindwin, a tributary of the Ayeyarwady. In the trade since the early 1970s, it first appeared in Ukraine and was widely considered a hybrid until natural populations were found, with the formal description following in October 2008. Males carry a thick band of bright red-orange on the flanks, and farm-produced fish seem to hold their colour better when stressed.

The dwarf barb, Pethia phutunio, is a small cyprinid from the lower Ganges and Brahmaputra river basins in Bangladesh and India. Frequently misidentified and quite rare in the trade, it is sometimes called 'spotted-sail barb' or 'spotted-tail barb'. Several congeners share its two black flank blotches, but it is smaller than all of them at 25 to 30 mm. It inhabits sluggish rivers, streams, ponds and swamps, often over deep mud or silt.

The Pookode Lake barb, Pethia pookodensis, is a small cyprinid described from Pookode Lake in Wayanad district, Kerala, and possibly endemic there. Pookode is a small forest lake and tourist destination that has suffered some degradation, and the IUCN classify the species as 'Critically Endangered'. It is most similar to P. ticto and P. punctata, with two dark flank markings, one on the front of the body and one on the caudal peduncle.

Pethia punctata is a small cyprinid endemic to the Western Ghats of southwestern India, where it appears restricted to west-flowing rivers. Poorly known in the hobby, it has a confusing taxonomic history and has been treated as both a synonym and a subspecies of P. ticto. It has a complete lateral line, two dark body blotches with the front one a scale row below the lateral line, and rows of spots in the dorsal fin.

Pethia reval is a small cyprinid endemic to western Sri Lanka, known from the Kelani and Maha Oya river systems and the drainages between them. Considered a red-finned colour form of P. cumingii before its description, it is a smaller fish, to 33.6 mm SL, with red dorsal, anal and pelvic fins (pale yellow in the Kalu River population). The Mahaweli River population appears to have been introduced.

The Narayan barb, Pethia setnai, is a small cyprinid common in rivers draining the Western Ghats of India, described from Sanguem in Goa. It is widely traded as 'Puntius' narayani, though the trade fish all have the serrated dorsal-fin spine of P. setnai, a feature 'P.' narayani lacks. The central of its three dark flank markings, beneath the dorsal fin, is uniquely pale and diffuse. In hill streams and smaller rivers it gathers in backwater pools and deeper, slower areas.

The Shalyni barb, Pethia shalynius, is a small cyprinid that appears to be endemic to Meghalaya state in northeastern India. It is known from only a handful of localities in the Khasi and Jaintia hills, mostly streams above 1200 metres with cool, clear, well-oxygenated water, and is apparently under threat from industrial activity. Very peaceful, it is still a poor choice for the general community aquarium because of its preference for cooler temperatures.

Pethia sharmai is a small cyprinid known only from a handful of localities around Chennai in Tamil Nadu, India. It mostly inhabits ponds and lakes, many of them in urban areas under pressure from urbanisation. Very peaceful but small and timid, it does best alone or with other diminutive species, and it is almost unheard of in the hobby outside India.

Pethia sp. 'Myanmar' appears to be an undescribed small cyprinid, supposedly collected in northern Myanmar. This fish has been widely misidentified and sold as the congener P. tiantian or 'Burmese bumble-bee barb'. Generally very peaceful, it suits the well-researched community aquarium in a mixed-sex group of at least 8-10, where rival males display their best colours.

Pethia stoliczkana is a small cyprinid that appears to range from Manipur state in northeastern India through Myanmar and Thailand to western Laos. Much of the literature confuses it with P. ticto, but the two do not occur in the same waters and the lateral line is complete in this species and incomplete in P. ticto. The form from Mandalay division in Myanmar is sometimes sold as Puntius sp. 'pearlscale'. It mostly inhabits shady, flowing streams and tributaries.

Pethia tiantian is a small cyprinid known only from the remote, mountainous area of Putao in Kachin state, northern Myanmar. Both known localities, the Nan Hto Chaung and the Mali Hka River, are part of the upper Ayeyarwady system. The species is only exported occasionally, and an undescribed fish often traded as 'Burmese bumblebee barb' is sometimes mislabelled with its name. It is subject to seasonal temperature fluctuations in nature.

The ticto barb, Pethia ticto, is a small cyprinid widely distributed through most of the Indian subcontinent, from Pakistan and Nepal to Bangladesh. Its name is frequently misapplied to P. padamya in aquarium literature, though P. ticto is much the less colourful fish and males lack reddish-orange pigmentation on the body. Morphology and colour pattern vary by population, and some populations have already been described as distinct species.