Goldstriped flying fox

About

Found drifting through murky stretches of large rivers across the Mekong basin and into Malaysia and Indonesia, this obscure Southeast Asian cyprinid, Crossocheilus cobitis, lives much of its life close to the riverbed. Sheltering under floating structures like logs and pontoons, and likely pushing out onto floodplains when seasonal rains raise water levels. It's a herbivore that grazes on algae, periphyton, and phytoplankton, with a narrow mouth well suited to scraping surfaces rather than gulping open-water food. Identification is tricky territory with this genus. A bold, unbroken lateral stripe running from the snout tip to the base of the tail, capped with a small concentrated blotch, is one of the more reliable visual cues. Two pairs of barbels and the characteristic disconnected lip structure of Crossocheilus, upper and lower lips joined only by a thin membrane rather than fused, help separate it from lookalikes. The problem is that virtually every laterally-striped Crossocheilus entering the trade gets lumped under the name siamensis regardless of actual identity, so what you buy may or may not be this species. It is also suspected to represent a species complex that taxonomy hasn't fully untangled yet. For a beginner-friendly herbivore with a genuinely interesting natural history, it's worth the uncertainty.