Crossocheilus nigriloba is a cyprinid endemic to Borneo, known from the Kapuas, Belayan and Mahakam rivers in Indonesian Kalimantan. Rarely seen, it is among the near-identical congeners traded as 'Siamese algae-eater' or 'SAE' but is simple to identify: the lower caudal-fin lobe carries dark pigment suffused with red, which gave rise to the trade name 'penguin flying fox'. The lateral stripe breaks into blotches when the fish are sparring, stressed or sleeping.

Moderate