Colletes fasciatus, Smith, 1853

Kuhlmann, Michael, 2007, Revision of the bees of the Colletes fasciatus-group in southern Africa (Hymenoptera: Colletidae), African Invertebrates 48 (2), pp. 121-166 : 123

The Colletes fasciatus -group

The species group is named after C. fasciatus , the first described representative of this group that was described by Smith (1853). Species of this group are isolated among the Colletes of the eastern hemisphere and North America by a characteristic combination of morphological features. Interestingly, a few South American Colletes show a close resemblance to species of the C. fasciatus -group, but at present it is unclear if this is an indicator for a phylogenetic relationship, or is caused by convergent evolution. Thus, a detailed study of the rich but little known South American Colletes fauna is needed to confirm the status of the below-mentioned features as synapomorphies of the C. fasciatus -group.

Both sexes are characterised by an oval-shaped metasoma with T1 being fairly close to regularly rounded anteriorly, and with the broadest part approximately in the middle of T2. T1 is slightly shortened compared with other Colletes species. In the males the tip of T7 is narrowly rounded (except for C. inornatus and C. testaceipes ) and often slightly protruding. The surface of the metasoma often has a bluish shine. The discs of all terga are densely covered with long erect hairs. In the males of all species, except for C. genalis , C. testaceipes and two of the undescribed specimens, the hind basitarsus is more or less broadened and sometimes partly modified (e.g. curved or crested), except in C. genalis and an undescribed male where the gonostylus and the wings of the penis valves are modified (e.g. elongate, reduced, broadened), extremely so in some species. In about half of the species the males have elongate antennae and swollen femorae and mid tibiae. In the females, the clypeal protuberance, in profile, is at least 3/4 of the width of the eye (less only in C. gessi ). The clypeus is strongly and regularly convex ( Fig. 1 ) (except in C. gessi ) and in C. cyanonitidus it has a slight longitudinal, median depression.

Figures

Figs 1–4. (1) Colletes albohirtus, clypeus of female, frontal view; (2) C. genalis, scopa on hind leg of female, dorsal view; (3) C. laticaudus, partly reduced scopa on hind leg of female, dorsal view; (4) C. karooensis sp. n., reduced scopa on hind leg of female, dorsal view. Scale bars: Fig. 1 = 0.5 mm; Figs 2–4 = 0.2 mm.