Pithecheirops Emmons 1993

Pithecheirops Emmons 1993, Proc. Biol. Soc. Wash., 106: 752.

Type Species: Pithecheirops otion Emmons 1993

Species and subspecies: 1 species:

Species Pithecheirops otion Emmons 1993

Discussion: Pithecheir Division. Closely related to Pithecheir and morphologically similar to species in that genus except for small details of molar occlusal patterns, and its much smaller and uninflated bullae, all of which were noted in the original description and comparisons. The contrasting middle ear features not clearly emphasized are: blade of manubium nearly parallel in Pithecheirops (perpendicular in Pithecheir), orbicularis apophysis present (absent in Pithecheir), pars flaccida present (absent in Pithecheir), and as a consequence of the latter, the posterodorsal rim of ectotympanic is incomplete (complete in Pithecheir). These states in Pithecheirops are likely plesiomorphic relative to those in Pithecheir, which agrees with the difference in extent of bullar inflation between the two. Whether these comparisons contrast a more ancestral species with derived ones within a monophyletic group (single genus), or whether Pithecheirops actually represents a different monophyletic clade (two genera) will have to be determined by surveying adults within a phylogenetic study employing as many data sets as possible and a broad range of Indomalayan genera.