Petagas

Gastromyzon extrorsus is a hillstream loach from the Kimanis and Petagas basins, draining the western Crocker Range in Sabah, Malaysian Borneo. The brown body carries up to nine thin gold stripes and the head a gold reticulate pattern. Growing to around 80 mm SL, it lives in swift, shallow streams with clear, oxygen-saturated water, and in aquaria needs clean, well-oxygenated water with strong turnover.

Gastromyzon lepidogaster is a hillstream loach from northern Borneo and the most widely-distributed member of the genus. It occurs in Sabah, Brunei and East Kalimantan. Colour is variable: large adults may be bright green, orange or barred, and can apparently change from barred to plain in a few seconds. It is occasionally available in the trade, where the orange form is particularly sought after.