Homalopsinae is a sub-family of Colubridae which contains some 10 genera and about 4 dozen species. They are typically stout-bodied water snakes, and all are mildly venomous. The genus Brachyorrhos may belong elsewhere. Two monotypic genera are notable for their unusual morphology: Erpeton possesses a pair of short, fleshy appendages protruding from the front of the snout, and Bitia has uniquely enlarged palatine teeth. Cerberus have been noted to use sidewinding to cross slick mud flats during low tide. Fordonia and Gerarda are the only snakes known to tear their prey apart before eating it, pulling soft-shelled crabs through their coils to rip them apart prior to ingestion.