Revision of the subgenus Kappa de Saussure of Mischocyttarus de Saussure (Hym.; Vespidae, Polistinae, Mischocyttarini) Author Silveira, Orlando Tobias text Zootaxa 2006 2006-09-28 1321 1 1 108 https://biotaxa.org/Zootaxa/article/view/zootaxa.1321.1.1 journal article 10.11646/zootaxa.1321.1.1 1175­5334 5071103 EFBAA3CB-89D7-4719-9E67-66D62D10E5EC Group of Mischocyttarus adolphi Zikán Species of this group share the following features: small size, body extremely robust, mesoscutum wider than long (Figs. 50, 57, 62, 65), first metasomal segment very short, variably convex dorsally (Figs. 51–52, 58–59, 63–64), median furrow reaching anterior margin of the propodeum, and pronotum anteriorly with a secondary margin. Some of these characters seem to be correlates of a trend of body shortening, and may as well be observed in the species of the M . socialis group, but these are larger wasps in which the pronotum has no secondary margin, and the male antenna has the apex very short. Mischocyttarus adolphi Zikán , M . latissimus Richards , M. frontalis (Fox) , M . santacruzi Raw , and M. fidus sp. n. further share a very elevated pronotal carina, and the metanotum is wider and less convex. Mischocyttarus anthracinus Richards is easily distinguished by its dark color pattern, practically without yellow marks. Richards (1978) did not recognize the close similarity between his new species M . latissimus and M . adolphi , considering the first as possibly related to M . immarginatus Richards and M latior (Fox) . His judgment was due to the extreme reduction of the occipital carina in M . latissimus (quite similar in M . adolphi ). The two species are in fact not so easy to delineate, occupying the opposite ends of an east­west continuum across northwestern South America. They are diagnosable by some color features, but these also vary geographically within the two observed non­sympatric groupings of specimens. However, the only available samples of males from Colombia (correlating to M . latissimus ) and Brazil ( M . adolphi ) have antennae with very different lengths (see figures 53 and 54), this being the only reliable structural character supporting maintenance of the two species concepts.