A58: Packer, L. 2000. The biology of Thrincohalictus prognathus (Perez) (Hymenoptera: Halictidae: Halictini). J. Hym. Res. 9:53-61.
Abstract: The Halictine bee Thrincohalictus prognathus (Perez) was studied in Israel in May and the beginning of June, 1998. Additional information was obtained from museum specimens. The species appears to be both common and widespread in northern Israel, particularly in the Galilee and Golan Heights where it occurs between altitudes of several hundred metres up to 1650m on Mount Hermon. Despite having an unusually elongate head, the species visits a wide range of flowers which generally do not possess a long corolla. Like most temperate halictines, only mated females overwinter and become active in the spring, as early as mid March. Males are found no earlier than mid May. The apparent age of females increases from March to May with newly eclosed, unworn individuals appearing in late May/early June. All worn early summer individuals were mated and had well developed ovaries. Thus, ovarian development and phenological data are inconsistent with the species being eusocial but are consistent with it being univoltine. The behaviour exhibited by paired females in artificial observation arenas indicates that T. prognathus possesses the repertoire of agonistic and cooperative behaviours usually found in halictines but that aggressive interactions predominate. Comparisons with other species indicate that the relative frequency of passing behaviour is very low and inconsistent with that expected for a communal species. I conclude that this species is probably solitary.