Protohermes costalis

Liu, Xingyue, Hayashi, Fumio & Yang, Ding, 2007, Systematics of the Protohermes costalis species-group (Megaloptera: Corydalidae), Zootaxa 1439, pp. 1-46 : 11

The Protohermes costalis species-group

Diagnosis. Median ocellus apparently transverse; posterior pair of ocelli widely separated, distance between them mostly equal to that between antennal bases. Male ninth gonostylus always enveloped by ninth tergum and invisible in dorsal view. Male tenth tergum short and subcylindrical, ventrally usually produced into a tubercle bearing a small tuft; tip usually slightly incised and densely setose. Male tenth sternum arched, basally more or less elevated at middle, apical margin usually incised medially. Female eighth sternum subtrapezoidal and narrowing toward apical portion. Female ninth abdominal segment mostly inflated laterally forming a pair of sac-like lobes.