Two-spot Bristletooth

About

The two-spot bristletooth (Ctenochaetus binotatus) is a mid-sized surgeonfish distributed across a sweeping range of the Indo-Pacific, from the reefs of East Africa all the way out to the Tuamoto Islands, and from southern Japan down to coastal Australia and New Caledonia. Like other members of the Ctenochaetus genus, it sports the characteristic bristle-like teeth that give it a surprisingly delicate touch when grazing. Rather than cropping algae in the way many tangs do, it scrapes thin films of detritus and microscopic algae from reef surfaces and rubble. That feeding habit puts it in an interesting ecological position: among the organisms it ingests are dinoflagellates that produce ciguatoxin, making this fish a notable link in the ciguatera toxin pathway. In the wild it tends to be solitary, working the deeper lagoons and seaward reef slopes. In an aquarium it fits reasonably well into a reef setup with enough rock work to replicate that grazing environment, though it deserves the space and water quality that intermediate-level marine keeping demands. Its two-spot name refers to a pair of small spots near the tail. Subtle compared to some flashier tang relatives, but a reliable identification marker once you know what to look for.