Composition of the Cloacal Gland Secretion of Tuatara, Sphenodon punctatus

Abstract

The lipophilic content of the cloacal gland secretion of the tuatara (Sphenodon punctatus) was investigated. GC/EI-MS Analysis of CH2Cl2 extracts of the secretions revealed triacylglycerols as major glandular constituents. Twelve major medium-chain fatty acids were found to be conjugated to glycerol in different combinations, resulting in complex mixtures. These acids were identified by transesterification and subsequent derivatization of natural samples, and their structures were verified by synthesis. The natural glycerides contain predominantly three of the following acids: octanoic (A), (E)- and (Z)-oct-4-enoic (B and C, resp.), (4E,6Z)-octa-4,6-dienoic (tuataric acid; D), (R)-2,6-dimethylheptanoic (E), (R)-2,6-dimethylhept-5-enoic (F), (Z)-dec-4-enoic (G), (4Z,7Z)-deca-4,7-dienoic (H), (R)-3,7-dimethyloct-6-enoic (I), (R)-4,8-dimethylnon-7-enoic (J), (2R,6S)-2,6,10-trimethylundec-9-enoic (K), and (2R,5E)-2,6,10-trimethylundeca-5,9-dienoic acids (L). Several additional acids, occurring in trace amounts only, were tentatively identified by MS. The elucidation of the absolute configuration of the acids was performed by GC on chiral phases. Individual tuatara show specific mixtures of glycerides with up to 100 components. The individual mixtures may permit individual recognition because the bouquets seem to be stable over years.

Heterogeneous tempo and mode of evolutionary diversification of compounds in lizard chemical signals

“…In these reptiles, a number of studies have failed to identify evidence revealing a role for quantitative traits biasing mating success during female mate choice (which has consolidated the view that sexual selection in these animals takes place via male–male contests; Olsson, Madsen, & Møller, 1998). In contrast, accumulating evidence suggests that this mechanism is fundamentally mediated by chemical signals (i.e., chemical compounds or/and a mixture of them; Martín & López, 2014, 2015) from secretions produced by follicular femoral and precloacal glands (Cooper, 1994; Escobar, Escobar, Labra, & Niemeyer, 2003; Flachsbarth, Fritzsche, Weldon, & Schulz, 2009; García‐Roa, Cabido, López, & Martín, 2016; García‐Roa, Carreira, López, & Martín, 2016; Martín & López, 2014). Indeed, recent literature confirms that both natural and sexual selection are affected by these secretions (López & Martín, 2005; Martín & López, 2006c; Martín, Ortega, & López, 2015; Martín et al., 2007).…”

Natural products from the integument of nonavian reptiles

“…113 Glycerides containing the common C 16 and C 18 acids also are present, but not together with 104-114.…”

Volatile Methyl Esters of Medium Chain Length from the Bacterium Chitinophaga Fx7914

“…In contrast, simple 2-methylalkanoic acids are found in bacteria, plants, and animals. The parent acids of the 2,X-dimethyl-branched esters reported here are also not known from nature, except for 2,7-dimethyloctanoic acid which occurs bound to glycerol in epidermal glands of the reptile, Sphenodon punctatus [46].…”