Pseudocimbex Rohwer, 1908

Archibald, S. Bruce & Rasnitsyn, Alexandr P., 2023, Cimbicidae (Hymenoptera, ‘ Symphyta’) in the Paleogene: revision, the new subfamily Cenocimbicinae, and new taxa from the Eocene Okanagan Highlands, Zootaxa 5278 (1), pp. 1-38 : 31-32

Genus Pseudocimbex Rohwer, 1908

Fig. 28 .

Pseudocimbex Rohwer, 1908, p. 526 .

Type species: Pseudocimbex clavatus Rohwer, 1908 , by original designation.

Diagnosis. Distinct from all other Symphyta by hind wing with M+Cu branching to M, Cu unusually basally; M and Cu at a low angle to M+Cu, almost aligned with it; cell mcu long, narrow, wedge-shaped; cu-a present, vertical. Also distinct from all other Symphyta by comparatively short antenna (about as long as half head width) with subspherical club consisting of several very short segments. Additionally distinct from Cimbicidae by lack of 2r-rs; by its wide costal space; and by presence of vein Sc.

Remarks. 2r-rs is not detected in the forewing in some cimbicid specimens described here, presumably by preservation. It is, however, confidently absent in both forewings of Pseudocimbex examined dry and wetted with ethanol ( Fig. 28 ). The very short antenna does occur in various Pergidae , however, there it is combined with an elongate and non-segmented club. In comparison with extant species, a placement of this fossil in either Cimbicidae or Pergidae remains ambiguous.

Species included. Type species only.

Figures

FIGURE 28. Pseudocimbex clavatus Rohwer holotype, UCM-18614, Tenthredinoidea incertae sedis, from the Florissant Formation:A, photograph; B, drawing; C, drawing of right forewing; D, drawing of left forewing; E, drawing of left hind wing. Scale bars A–B, 5 mm; C–D, 3 mm.