Zigrasimecia hoelldobleri Cao, Boudinot & Gao, 2020

Abstract, Júlio Cezar Mário Chaul, 2023, A revision of the Cretaceous ant genus Zigrasimecia Barden & Grimaldi, 2013 (Hymenoptera: Formicidae: † Zigrasimeciinae), Zootaxa 5325 (3), pp. 301-341 : 321

Zigrasimecia hoelldobleri Cao, Boudinot & Gao, 2020

Diagnosis (worker). Large species. Head subquadrate in full-face view. Body pilosity composed of long, flexuous, mildly clavate, and apically truncate setae. Labral distal margin fringed with soft setae. Dorsal mesosomal outline conspicuously convex; propodeum without strongly marked corners between the dorsal and posterior surfaces. Petiolar node apex brief, but not sharp, the transition from the anterior to the posterior surfaces being a short, curved surface.

Comments. The holotype of this species is very distinct for its pilosity and large size ( Fig. 14 ), being easily separated from all remaining species of Zigrasimecia by those respects. Two morphospecies are similar to Z. hoelldobleri , however their poor preservation prevents any conclusive identification. See comments under morphospecies Zigrasimecia ufv-04 about a possible complex of species formed by it, Z. hoelldobleri and Zigrasimecia ufv-06.

The paratype CNU-HYM-MA2019054 of Z. hoelldobleri , differs considerably from the holotype and is here taken out of the type series of the species for not sharing the same type of setation with the holotype. Moreover, CNU-HYM-MA2019054 propodeum appears to have better-defined faces and the petiolar node with better defined top and posterior faces. The specimen is probably conspecific to specimen CNU-HYM-MA2019065, both are likely members of a new species similar to Z. ferox , but differing from the latter by having somewhat longer and more abundant pilosity on the body, the apex of the node oblique rather than flat, and a slightly different shape of the head, with the anterior section just posterad the clypeal lobes a bit more constricted (see comments about specimen CNU-HYM-MA2019065 below). Alternatively, the limits of Z. ferox could be broadened to include specimens CNU-HYM-MA2019065 and CNU-HYM-MA2019054, something that should preferably be done when more specimens are available and/or can be physically examined.

The distalmost row of very thin, crooked setae on the labrum of Z. hoelldobleri holotype is an odd and unique trait of the species; however, it is difficult to check in specimens with a retracted labrum (most of the known specimens so far); therefore, it could be, in fact, a more common trait in the genus.

Figures

FIGURE 14. Relative body size comparison of all described species of Zigrasimecia (with morphospecies Zigrasimecia ufv-11 included, see Section 3.3 of text).