The Malagasy cichlid genus Ptychochromis is revised and five new species are described, one of which is presumed to be extinct. The three valid nominal species, P. oligacanthus, P. grandidieri, and P. inornatus, are redescribed with diagnoses provided for each. A phylogeny of ptychochromin cichlids, derived from the simultaneous analysis of morphological features and nucleotide characters from a combination of mitochondrial and nuclear genes is presented. Ptychochromis is diagnosed by a suite of derived features of the pharynx, infraorbital series, and palatine morphology. In addition, the sister taxon to Ptychochromis, Ptychochromoides katria, is removed from Ptychochromoides and placed in its own genus, Katria, which is described herein as new. Katria is diagnosed by a unique pigmentation pattern, the absence of paired anterior gas bladder chambers that approach the neurocranium, an elevated vertebral count, and a slender caudal peduncle. An unnamed clade comprising Ptychochromis and Katria is diagnosed by a suite of derived features of the pharynx, sensory canal system, supraneural patterning, and palatine morphology.