Age related differences in lipophilic compounds found in femoral gland secretions of male spiny-footed lizards, Acanthodactylus erythrurus

Although chemoreception plays an important role in social organization of many lizards, only a few studies have examined the chemicals found in secretions used for intraspecific communication. We report the composition of the secretion of the femoral glands of males of the spiny-footed lizard (Acanthodactylus erythrurus). On the basis of mass spectra, obtained by GC/MS, we identified 45 lipophilic compounds, including several alcohols ranging from 10 to 29 carbon atoms (mainly hexacosanol and tetracosanol), steroids (mainly cholesterol and dehydrocholesterol), n-C9 to n-C20 carboxylic acids, esters of carboxylic acids, and minor components such as lactones, ketones, squalene and a-tocopherol. Some of these compounds are reported for the first time in lizards. Adult and subadult males differed in the composition of secretions, with C9 to C15 carboxylic acids being more abundant in younger than in older lizards, whereas C16 to C20 carboxylic acids were more abundant in older lizards. Also, older lizards had significant lower proportions of cholesterol and campesterol but higher proportions of dehydrocholesterol.