A new cichlid: Ptychochromis mainty

My personal favorites are fishes from the family Cichlidae. This group comprises of perhaps 2000-3000 very diverse freshwater species. This makes them one of the largest vertebrate families. 

Almost all of these fishes occur in the southern hemisphere. They have long been an important source of food for humans with the consequence that in places such as Lake Tanganyika, they are so overfished that they are in danger of disappearing. Outside the southern hemisphere, the cichlids are known mostly to tropical-fish enthusiasts through a couple of colorful representatives, e.g. the discus or the freshwater angelfish. However, nowadays people will likely know cichlids from tilapia which are increasingly farmed as a food source in the northern hemisphere. 

Today's newcomer belongs to a small genus that is endemic to Madagascar - Ptychochromis. The species was named after the Malagasy word for black, mainty, referring to the species’ uniform dark

pigmentation pattern in preservation and large black midlateral blotch in life.

For the experts: We describe a new species in the endemic Malagasy cichlid genus Ptychochromis. Ptychochromis mainty, new species, is known from four individuals, all collected in the Fort Dauphin region of southeastern Madagascar, and shares a palatine morphology (eastern-type palatine) with other eastern congeners. Ptychochromis mainty is distinguished from all congeners by a nearly uniform dark brown to black pigmentation pattern in preservation and by the presence of a relatively continuous and expansive black longitudinal midlateral blotch in life, extending from the posterior margin of the opercle to the caudal peduncle. The new species is further distinguished from other eastern Ptychochromis species by having minimal or no overlap of the first supraneural with the dorsoposterior region of the supraoccipital crest (vs. marked overlap). We present a molecular-based phylogeny for all available Ptychochromis species, which supports the hypothesis that P. mainty is a distinct taxon. The new species is recovered as the sister taxon to P. grandidieri within a clade comprising species with an eastern-type palatine morphology. We present a geometric morphometric analysis that provides additional evidence to distinguish P. mainty from congeners.