Yamuna

This species is sometimes sold under the trade name of 'chameleon fish' due to its ability to rapidly change colour, especially when breeding or stressed. It was originally described as Labrus badis by Hamilton but Bleeker reclassified it as Badis buchanani in 1854; he had adopted the species name 'badis' as the new name for the genus and wished to avoid using a tautonym. At that time the use of tautonyms was avoided in zoological taxonomy but is now permissible under ICZN ru...

Barilius spp. are near-exclusive surface-feeders preying mostly on flying insects in nature with some small fishes and benthic invertebrates probably taken as well but in the aquarium they're largely unfussy and will accept most foods.

The physical appearance of B. almorhae sensu stricto is something of a mystery. No pictures of live specimens appear in any scientific publications we've read and we've been unable to find a certified image of one anywhere meaning it's possibly never been seen in the aquarium trade. Instead the most commonly available members of the nominal species grouping seem to be B. lohachata, B. sp. 'Kosi' and B. sp. 'Teesta' (see individual notes below), plus the assorted hybrids that have appeared since the turn of the century (Grant, 2007).

Endemic to the Ganges and Brahmaputra river basins and thus occurs in northern India, Nepal and Bangladesh. Type locality is 'the Yamuna River, and northern rivers of Behar and Bengal'. The distribution of the genus as a whole is interesting because these fish occupy the area that geographically separates Indian and Southeast Asia barbs and it has been theorised that they may represent an evolutionary 'link' species...

This species occasionally appears in the ornamental trade, usually as 'striped hill trout' or 'banded hill trout'. It can be distinguished from congeners by the following combination of characters: lateral line complete with 40-42 scales; barbels absent; 10-13 anal-fin rays; body with 9-11 dark blue vertical bars; last dorsal-fin ray extending to caudal-fin base.

Probably a micropredator feeding on small insects, worms, crustaceans and other zooplankton in nature. In the aquarium it should accept dried foods of a suitable size but should not be fed these exclusively. Daily meals of small live and frozen fare such as Daphnia, Artemia, Moina, etc., along with good quality flakes and granules will result in the best colouration and encourage the fish to come into breeding condition.

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.