Traumatomutilla americana (Linnaeus, 1758)

Bartholomay, Pedro R., Williams, Kevin A., Lopez, Vinicius M. & Oliveira, Marcio L., 2019, Revision of the Traumatomutilla americana species group (Hymenoptera: Mutillidae), Zootaxa 4608 (1), pp. 1-34 : 4

Traumatomutilla americana species-group

Diagnosis. The females of this species group can be defined by a unique combination of characters: posterior margin of vertex armed laterally with a pair of smooth impunctate subtriangular or subrectangular tubercles, one on each side; mesonotum not emarginated anterior to propodeal spiracles, slightly rounded laterally, lacking longitudinal medial carina; scutellar scale distinct, disconnected from anterior transverse carina; apex of middle and hind femora rounded; T1 with dorsal and anterior faces indistinct, smoothly rounded into each other; pygidial plate subovate, defined by lateral carina at least at apical half and with longitudinal subparallel often interrupted costations. Additionally, the genal carina is present and short, broadly separated from tubercles of vertex. The males can be defined by having the vertex slightly swollen medially, posterior to occiput; clypeus with a pair of closely spaced short, usually blunt tooth-like projections; short truncate axillar projection with well-defined posterior face; scutellum simply convex; T1 subnodose, with distinct anterior and dorsal faces. Additionally, most species have a small cluster of setae anteromedially on S2 and the pygidial plate irregularly rugose throughout, except T. quadrum which has a distinct posteromedial pit filled with setae on S2 and the pygidial plate mostly unsculptured, smooth, with dense shallow micropunctures apicolaterally.

Included taxa. Three valid species: T. americana ( Linnaeus, 1758) , T. ocellaris ( Klug, 1821) , and T. quadrum ( Klug, 1821) .

Distribution. East of the Andes ranging from Colombia and Venezuela to Argentina.

Remarks. The T. americana group is one of the most commonly encountered groups throughout South America. As in other smaller-bodied groups, the mesosoma is comparatively robust and box-like with the posterior face of the propodeum conspicuously longer than the dorsal face. Males of the T. americana group have consistent external and genitalic morphology, with the exception of the males of T. quadrum which have a slenderer and nearly parallel cuspis throughout, in contrast with the abruptly tapered apical half or third of the other males in the group. Examination of the types of T. bellifera ( Gerstaecker, 1874) , T. lunigera ( Gerstaecker, 1874) and T. compar ( André, 1895) revealed that the first belongs to the T. trochanterata species-group and the latter two belong to the T. inermis species-groups. Some females from other species-groups approximate the T. americana species-group in overall morphology by having the apex of meso- and metafemora apparently rounded ( T. compar (André) , T. tetrastigma ( Gerstaecker, 1874) and T. hemicycla ( Gerstaecker, 1874) from the T. inermis species-group) and/or by having the pygidial plate comparatively broadened ( T. tulumba Casal, 1969 , from the T. trochanterata species-group). However, species from the T. inermis group have the pygidial plate subpyriform and species from both groups have T1 narrower and more distinctly petiolate.