Brevis Yunnanilus

Yunnanilus brevis is one of several highly localised nemacheilid loaches endemic to the lakes and associated streams of the Yunnan plateau in southwestern China. The Dianchi Lake system, its primary habitat, has suffered severe pollution, overfishing, and habitat modification over recent decades, rendering several of its endemic fish species extremely threatened. Yunnanilus brevis has Conservation status and is primarily available in the hobby through captive-bred stock from a small number of dedicated breeders.

The species is compact and short-bodied compared to most Yunnanilus, reaching barely 4.5 cm. Its patterning is subtle — a mottled brown and cream dorsal surface with a faint lateral blotch pattern. In aquaria it is active and sociable, forming loose schools in the mid-to-lower water column. It appreciates cool, clean water and performs poorly above 22 °C.

Keeping and breeding Y. brevis contributes meaningfully to conservation awareness of Yunnan's threatened freshwater biodiversity. The species is a good companion for other cool-water Chinese fish and presents a compelling story for aquarium education purposes.

Water: 16–22°C, pH 7.0–8.0, GH 5–15, KH 3–10; moderate flow and good oxygenation; the alkaline end of the range reflects Dianchi Lake chemistry. Tank: 60 L minimum; open swimming areas with rocky structures; gentle to moderate flow; slightly harder water than most hillstream species. Feeding: Omnivore — small sinking pellets, frozen daphnia and cyclops, spirulina flakes; easy to feed once settled. Breeding: Has been bred in captivity by specialist breeders; condition with cool water changes; scatter-spawner over fine substrate. Compatibility: Peaceful; keep with other cool-water Chinese species; avoid tropical fish requiring temperatures above 24°C.