Chelostoma grande species group

The four representatives of the Chelostoma grande species group are characterised in both sexes by a very long proboscis (Fig. 10, 11). Additional characters of the females are the large body length, which is at least 8 mm but mostly longer, the basally distinctly constricted terga 2-3 (Fig. 10), and the long labrum, which is at least 2.5× as long as apically wide (Fig. 13). An additional character of the males is the presence of two sharp and tooth-like projections on the hypostomal area formed by the hypostomal carinae in the basal half (Fig. 16). The species are oligolectic on Dipsacoideae ( Caprifoliaceae), most likely including C. scabiosae, for which only one pollen load was available for study.