Eye morphologies in Ptomaphagus. Lateral view of head capsule and compound eye or eyelets (arrowheads) of Ptomaphagus species discussed in this paper. Ptomaphagus cavernicola and P. consobrinus are macrophthalmic and were used as outgroups in this study. Ptomaphagus shapardi, the only soil-dwelling species in the hirtus-group, has reduced eyes and is considered microphthalmic. The other 17 members of the hirtus-group are extremely microphthalmic.