Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo 2, 166 10 Prague, Czech Republic.
Bombus lucorum (L.) is a widely distributed bumblebee species, occurring
through whole Palaearctic region. To attract females for mating, males mark their territories
with a pheromone produced in the cephalic part of their labial gland (patrolling behaviour).
B. lucorum males show wide colour variations. Two forms (blonde and dark)
occurring in Sweden were separated morphologically (Bergström et al.,
1973). The colour variability is correlated with the composition of the labial gland secretion.
While the blonde form contained ethyl (Z)-9-tetradecenoate as the main
component, the dark form produced mainly ethyl dodecanoate. The purpose of our study was
to investigate whether the Czech form can be correlated to one of the Scandinavian forms or
if there exist more forms in our territory.
Labial gland secretions of 22 B. lucorum males, collected in 6 localities in the
Czech Republic, were analysed. The secretion consists of 60 compounds with ethyl
(Z)-9-tetradecenoate being the main component. Although the collected males
showed variability in colours to certain extent, all individuals belonged to one form according
to the chemical composition of their labial gland secretions. The form of B. lucorum
occurring in the Czech Republic corresponds well to the Scandinavian blonde form of this
species.
Supported by the Grant Agency of the Czech Republic (#203/98/0453).