Upper fish: One of the scale-scraping aggressive mimics of Lake Malawi, the haplochromine cichlid Corematodus shiranus. Lower fish: Its model and chief prey, which is only very distantly related to it—a member of the endemic Malawi tilapia species flock, which includes Oreochromis ("Nyasalapia") squamipinnis and several related species. Photo copyright © 1997 by M. K. Oliver.

Note how convincingly the haplochromine's color pattern resembles that of the tilapiine, from the bright silvery ground color to the irregular outlines of the black bars. It is this similarity, together with behavioral mimicry, that permits the Corematodus to swim (in relatively low numbers) among shoals of Oreochromis, approach them, and rapidly bite at the caudal fin, rasping small epithelium-covered scales from the fin. These scales seem to constitute the chief diet of the two known Corematodus species; hundreds of the scales are found in the gut contents (Fryer & Iles, 1972). Be sure to look at the peculiar jaws and dentition characterizing this genus, as illustrated for the other species, Corematodus taeniatus.

Last Update: 16 November 2000 Web Author: M. K. Oliver, Ph.D. Copyright © 1997-2021 by M. K. Oliver, Ph.D. - ALL RIGHTS RESERVED