Polybia (Omega), (de Saussure 1854) (de Saussure, 1854)

Borges, Rafael Cabral & Silveira, Orlando Tobias, 2019, Revision of the species-group of Mischocyttarus (Omega) filiformis (de Saussure 1854), with description of three new species (Hymenoptera, Vespidae), Zootaxa 4657 (3), pp. 545-564 : 546-547

The group of M. (Omega) filiformis (de Saussure 1954) ; sensu Silveira (2008).

This species-group is composed of seven species (three of them newly described here) that share the follow- ing characters: posterior part of the head around the occipital foramen forming a deep cavity, its ventral portion horizontal and sharply margined, like a shelf (see Fig. 17 ); occipital carina well developed, ocelli positioned as a low isosceles triangle; proepisternum with anterior margin strongly raised and reflexed (but not double-margined); pronotum without lateral fovea, and with anterior lamella strongly raised medially and reflexed, the region immediately posterior without a secondary margin; pronotal carina strongly produced at sides forming lateral humeral lobes, profile from above concave forwards, carina continuous (from side to side), with the lamella high and a little bent backwards at centre, not extended downwards at the sides of the pronotum; mid tibia with a single spur; first metasomal segment variably elongate; male antenna spiral rolled; nest comb as an ordinary cluster of cells.

This species-group can be promptly distinguished from other Mischocyttarus (and other Polistinae) by having a single midtibial spur.

Figures

FIGURES 14–20. Head in frontal view (except 17, posterior view) (females; all from Brazil, except 14 and 16) 14: M. filiformis (Bolivia, Beni; NHM); 15 and 17: M. omicron (Pará, Carajás; MPEG); 16: holotype of M. napoensis (Ecuador; NHM); 18: holotype of M. kallindusfloren sp. nov. (Pará, Carajás; MPEG); 19: holotype of M. asahi sp. nov. (Pará, Carajás; MPEG); 20: M. buyssoni (R. de Janeiro; MPEG); all scales = 0.50 mm. Figure 21: colony and nest of M. filiformis (Pará, Belém; campus of MPEG)—nest size 1,5 × 1,2 cm.