Ptychochromis is a genus of cichlids endemic to rivers and lakes in Madagascar. One species (P. grandidieri) can also be seen in brackish water. Most species in this genus are threatened, and P. onilahy is probably extinct. Most reach a length of 12–15 cm (4.7–5.9 in), but P. insolitus only reaches 5.5 cm (2.2 in), while P. grandidieri and P. oligacanthus reach 21–25 cm (8.3–9.8 in).