Genus Gerarus Scudder, 1885.

Type species. Gerarus vetus Scudder, 1885.

Composition. We restrict the genus to the species Gerarus vetus Scudder, 1885, Gerarus bruesi Meunier, 1909, Gerarus fisheri (Brongniart, 1885) Burnham, 1983, G erarus collaris Handlirsch, 1906, and Gerarus danielsi Handlirsch, 1906 (see above).

Diagnosis. Burnham (1983) compared Gerarus to Nacekomia, Progenentomum, Genentomum and Gerarulus. Kukalová­Peck & Brauckmann (1992) did not give a new diagnosis of the genus. Thus we propose a new diagnosis, based on forewings characters: ScP long, straight, anteriorly pectinate; branches of ScP simple or shortly ramified; RP with few distal branches; MA differentiated into MA1 and MA2; MA1 generally connected to RP by a short cross­vein or shortly fused; MP ramified very proximally; CuPa present, more or less weak; CuPb ramified with an anterior branch long or reduced, and either connected or not to CuPa.

Note. The very long, spiny pronotum of numerous Gerarus spp. is a strong synapomorphy (Burnham 1983; Kukalová­Peck & Brauckmann 1992) but is unknown in Gerarus bruesi, thus it is not possible to determine if it is at the family or genus level.

Discussion. Gerarus vetus as figured by Kukalová­Peck & Brauckmann (1992: figs. 4,10,13) has a simple MP, suggesting closer relationships with Orthoptera than with G. bruesi and G. danielsi, which have an MP which is clearly and very proximally ramified. In his composite reconstruction of the holotype of G. vetus, Burnham (1983: fig. 4) did not figure a simple but a forked MP vein. It is not certain if the holotype of G. vetus and the specimens studied by Kukalová­Peck & Brauckmann (1992) belong to the same species or even genus. Thus, the monophyly of this genus remains unclear.