Rhogogaster

Taeger, Andreas & Viitasaari, Matti, 2015, European Rhogogaster s. str., with notes on several Asian species (Hymenoptera: Tenthredinidae), Zootaxa 4013 (3), pp. 369-398 : 371

Definition of Rhogogaster

The genus belongs to the Tenthredininae . It is difficult to separate from Tenthredo s.l. (about 1000 species), and its status requires future evaluation in the course of a re-classification of the Tenthredininae . Currently, Rhogogaster is kept separate, but it is possible, once phylogenetic relationships of the Tenthredininae have been analysed more thoroughly, that the species will have to be included in Tenthredo in the future.

Ross (1937) used the shape of the mandibles to characterize Rhogogaster in a broader sense. The more or less rectangular basal tooth of the right mandible (fused 3rd and 4th tooth, Fig. 1 c) was also used for the separation of Rhogogaster s.l. by Zhelochovtsev & Zinovjev (1988), Taeger (1991) and Goulet (1996). Unfortunately, this character is frequently hard to see, as the mandibles are usually closed and covered by the clypeus and labrum, and older pinned specimens are difficult to relax to enable the mandibles to be opened. In males, for example in R. punctulata , the rectangular tooth may be flat and tends to be bidentate ( Fig. 1 d). Nevertheless, this character is considered to be the principal character of the genus in a broader sense, even if it is only reliable for females.

Figures

FIGURE 1. a – b: Rhogogaster scalaris ♀ alive, from France, Midi-Pyrénées: Barèges 3 km ENE; 1450 m— a dorsal view b lateral view. c – d: face and shape of mandibles and clypeus in frontal view— c R. scalaris ♀, d R. punctulata ♂. e – f: head and thorax laterally, arrows in direction of anterior and ventral margin of pronotum— e R. sibirica: without submarginal furrow, f Tenthredo aericeps Konow, 1907: with submarginal furrow. g – h: apex of hind tibia, tibial spurs and basal tarsomeres— g T. virescens (lectotype), h R. scalaris (lectotype).