Abstract
Lizards possess epidermal glands which produce secretions playing a role as semiochemicals. Classic anatomical studies do not give detailed information on the nature of the secretions. Here I used GC-MS analysis of gland secretions to focus on the molecular structure of femoral gland secretions in two xeric-adapted agamid lizards, Uromastyx aegyptia and U. ornata. Steroids, alcohols, carboxylic acids, alkanes, aldehydes, carboxylic acid esters and squalene were detected as lipidic compounds. Monoglycerides of fatty acids and glycerol monoethers of long chain alcohols previously only detected in Lacertidae and Gekkonidae were also identified. The compounds constituting femoral secretions are possibly an adaptation to hot and dry habitats, with specific chemical profiles for each species. The presented data support the hypothesis that Uromastyx (and lizards in general) use femoral gland secretions for chemical communication.