Zigrasimecia ufv-08, 2023

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 : 328-329

Zigrasimecia ufv-08

( Fig. 17 )

This morphospecies is composed of two specimens that were originally in one single piece (separated for study). The amber matrix is extremely dirty and both specimens appear desiccated (the entire body "sculpturing" appears to be an artifact). The specimens do not have conspicuous standing setae, instead, they have a curved small pilosity on the head which is similar to Zigrasimecia ufv-11 (see below). They have a subrectangular head. Compound eye has around 50 ommatidia. The frontal carina is poorly developed. The propodeal dorsal and descending surfaces are separated by a strong angle. The petiole is somewhat long and low, the node top surface is round, not bilobed (very distinct from any shape seen in other species or morphospecies). If better-preserved specimens confirm that the traits attributed to this morphospecies are not artifactual (some sclerite shapes could be a result of stretching), it will certainly belong to a new species, as this combination of traits is unique in the genus. This morphospecies was excluded from the dichotomous identification key.

Examined material. Workers (UFV-LABECOL-010579 and UFV-LABECOL-010580). Hukawng Valley, Kachin Province, Myanmar; Lower Cenomanian (ca.98.79 ± 0.62 Ma) [ JCMCC] .

Figures

FIGURE 17. Morphospecies Zigrasimecia ufv-08, two specimens originally in the same piece (separated for study). Specimen UFV-LABECOL-010580 in A, C and D and specimen UFV-LABECOL-010579 in B. A, full-face view of head; B, profile of left side of body; C, zooming of left side of metasoma in profile; D, detail of mesosoma in dorsal view. Scale bars are 0.2 mm.