Identification and analysis of the male labial gland secretions of three species of Bombus (Thoracobombus) (Hymenoptera: Apidae)

The males of the three species of bumblebees, Bombus (Thoracobombus) ruderarius (Müller), B. (T.) persicus Radoszkowski and B. (T.) mesomelas Gerstaecker collected from Vikan village, Qazvin province and their male labial gland secretions were analyzed by gas chromatography/ mass spectrometry (GC/MS) and components of their extracts were identified. The major compounds were a complex mixture of alkenols, alkenals, fatty acids, hydrocarbons, wax type esters and steroids. The main component of male labial gland secretions of B. ruderarius, B. persicus and B. mesomelas were determined to be 9-hexadecenol (42.1%), Z-13-octadecen-1-yl acetate (81.8%) and Z-12-pentacosene (34.4%), respectively. Results showed that if detection of species in male bumblebees would be difficult by using morphologic characters, then identification could be confirmed by detecting main component of male labial gland of these bees.