A New Stygobitic Crayfish from Mexico, Procambarus Cavernicola (Decapoda: Cambaridae), with a Review of Cave-Dwelling Crayfishes in Mexico

Procambarus (Austrocambarus) cavernicola, a new species of stygobitic crayfish known only from Gabriel Cave, Oaxaca, Mexico, is described. The new species is characterised by a body that lacks pigmentation, except for small purple spots on the eyes; with small setae on the tip of the eye; elongated chelipeds, with the surface of chela covered with small tufts of short setae; first pleopod of form I male with mesial process elongated and conical, triangular central projection, reduced cephalic process and cephalic shoulder forming convex border; annulus ventralis with preannular plate covered with short setae, postannuluar plate oval-shaped, with blunt tubercles. The new species is morphologically similar to other stygobite members of the subgenus Austrocambarus from the Oaxaca–Veracruz area, whose relationships are discussed. The distributions and levels of adaptation to the subterranean environment of 16 cave-inhabiting taxa of Procambarus in Mexico are reviewed.