Is† Umenocoleus a roach or a beetle?
The systematic position of the Cretaceous genus †Umenocoleus Chen & Tan is re-evaluated. The re-assignment in 2014 back to Coleoptera is rejected based on numerous morphological features incompatible with such a placement. This includes an orthognathous head, multi-segmented antennae, the lack of a cephalic neck region, the exposed cervical membrane, a dorsal surface with cup-shaped punctures but without tubercles, moderately sclerotized forewings with rounded apices and lacking window punctures, the lack of an elevated mesoscutellar shield, and unfolded hind wings with numerous veins. Supposedly ancestral coleopteran features are implausible considering the comparatively young age (Early Cretaceous). As previously suggested, the genus is phylogenetically closely related to “roachoids” like †Ponopterix Vršanský & Grimaldi and †Petropterix Vršanský (†Umenocoleoidea Chen & Tan; see Vršanský, 2003) and probably also to †Alienopteridae (†Alienoptera).