Chemical composition of precloacal secretions of Liolaemus lizards.

Interspecific chemical variation of precloacal pore secretions of Liolaemus lizards was characterized in 20 species, and intraspecific chemical variation was characterized using nine individuals of L. bellii. The latitude (Chile, 18 degrees to 33 degrees South latitude) and altitude (100 to 4350 m.a.s.l.) of the capture sites were recorded, as well as the number of precloacal pores of each lizard. Secretions were analyzed by GC-MS. A total of 49 compounds were found distributed among the 20 species of Liolaemus. Different chemical patterns occurred at intra- and interspecific levels. Compounds belonged to three main families: n-alkanes, long chain carboxylic acids, and steroids. Cholesterol and five carboxylic acids (tetradecanoic, hexadecanoic, hexadecenoic, octadecanoic, and Z-9-octadecenoic) appeared in all species. The number of precloacal pores correlated positively with altitude and negatively with latitude, suggesting that lizards produce more secretions under harsh environments.