Interestingly some observations suggest that the character of the highest-ranked, or alpha, fish appears to affect that of the whole group though it must be said that scientific studies of botiid loach behaviour are virtually non-existent. It certainly seems that they display a degree of ‘personality’ with some specimens being naturally bolder/more aggressive than others. The alpha is normally the largest specimen within the group and often female.

Sound also appears to be an important factor in communication since these loaches are able…

The genus Danio contains only the type species, D. dangila, separated on the basis of its larger size and the shape of the caudal-fin, which in adults is only slightly emarginate or even truncate in shape, a feature it shares only with Tinca tinca (the common tench) among other cyprinids.

The remaining species, of which B. rerio is thought to be the most ancient, are included in the revalidated genus Brachydanio Weber & de Beaufort, 1916.

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…

This species’ identity was settled and a neotype designated by Knight (2013) who also revalidated the congener P. canius (Hamilton, 1822) and described the closely-related P. aurea.

These three had previously been considered to represent geographic forms of P. gelius, albeit on a tentative basis, with the validity of P. canius having been discussed since the late 19th century.

Apparently most abundant in shallow streams and minor tributaries, sometimes at relatively high altitudes, and apparently shows a preference for substrates of mud or silt. Given the extent of its range it would seem sensible to assume that it inhabits various habitat-types which also vary in water depth, flow, and turbidity depending on the time of year.

To date the species is known mostly from the upper Ayeyarwady River basin in northern Myanmar where it’s been collected close to the city of Myitkyina in Kachin State as well as around nearby Lake Indawgyi, the largest inland lake in Southeast Asia and home to ten globally threatened bird species.

The lake and surrounding area were designated a protected zone by the Ministry of Ecotourism in 1999 and now form the Indawgyi Lake Wildlife Sanc…

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.