S. Mahunka szerk.: Folia Entomologica Hungarica 64. (Budapest, 2003)
3. Face entirely yellow-red, usually head and pronotum yellow to red; apical punctures of fused 2+3 tergites dorsally extended to 1/4 of tergites length and much less ventrally S. flavipes Hartig, 1843 Head and pronotum black, at most reddish near mouth; apical punctures of fused 2+3 tergites dorsally extended at least to 1/3 of tergites length 4 4. Fl of male distinctly expanded basally and apically (Fig. 7A); scutellar foveae separated by wide septa (Figs 5A, 7D); notauli weakly impressed, very indistinct or absent anteriorly (Fig. 5A) S. crassicornis (Curtis, 1838)' Fl of male not expanded, slightly curved and with the inner surface of the curve flattened (Fig. 7B); scutellar foveae separated by narrow septa as wide as foveae wideness (Fig. 7C); notauli incomplete and more deep S. clandestinus Eady, 1952' 5. Radial cell 2.5-3.0 times as long as wide (Figs 8A-C); Fl of male strongly expanded apically (Figs 8F-H) 6 - Radial cell 2.0-2.5 times as long as wide (Figs 8D-E); Fl of male weakly expanded apically and basally, slightly curved in middle (Figs 8L-M) 8 6. Apical punctures forming relatively narrow band, extended not more than to 1/4 of 2+3 fused tergites length (Fig. 4B); Fl at least 1.5 times as long as F2, pedicel distinctly longer than broad (Figs 8F, I); veins pale, radial cell 2.5-2.8 times as long as broad (Fig. 8A); face and mesosoma black in both sexes S. pallidipennis Mayr, 1872 - Apical punctures forming relatively wide band, extended to 1/2-1/3 length of 2+3 fused tergites (Fig. 4 A); F 1 as long as F2, pedicel as long as broad or only slightly longer than broad, usually spherical in male (Figs 8G, H, J and K); other characters variable 7 7. Radial cell not more than 2.5 times longer than broad (Fig. 8C); wing veins dark brown; Fl of male strongly expanded apically (Fig. 8G); face (especially in males) and often mesosoma (especially in females) partially yellow, orange or red S. umbraculus (Olivier, 1791) Radial cell longer, 2.5-2.7 times as long as broad (Fig. 8B); venation ligth; first fagellomere of male less expanded apically (Fig. 8H); face and mesosoma black in both sexes S. diaphanus Houard, 1911 Closely related species but easily distinguishable by Fl of males (see Eady 1952, Nieves-Aldrey & Pujade-Villar 1985, Nieves-Aldrey 200lfc, Pujade-Villar 2002).
