DISCRIMINATION OF THE BUMBLEBEE SPECIES B OMBUS-CRYPTARUM AND B-LUCORUM BY MEANS OF MALE LABIAL GLAND SECRETIONS AND MORPHOLOGICAL CHARACTERS (HYMENOPTERA, APIDAE)

Three taxa of the subgenus Terrestribombus Vogt 1911 [genus Bombus Lin naeus 1758] have been reared in the laboratory and assigned by the mai n component (MC) Of the male labial gland secretions to the species te rrestris Linnaeus 1758 (MC = 2,3-Dihydrofarnesol), lucorum Von Linne 1 761 (MC = Myristoleic acid ethyl ester) and cryptarum Fabricius 1775 ( MC = Lauric acid ethyl ester). Individuals of terrestris can be identi fied by proboscis-length, individuals of lucorum and cryptarum by the Rf-values of Phosphoglucomutase on PAGE-gel. Coloration and boundary o f the collare at the edge of the pronotolobus of queens are reliable c haracters to discriminate cryptarum and lucorum. 39 compounds includin g mainly hydrocarbons, alcohols and esters are identified from the mal e labial glands of cryptarum.