Growth and age of the southernmost nocturnal gecko Homonota darwini: a skeletochronological assessment

PIANTONI CARLA, IBARGUENGOYTIA NORA RUTH, CUSSAC VICTOR

AMPHIBIA-REPTILIA

BRILL ACADEMIC PUBLISHERS

Año: 2006 p. 393 - 400

0173-5373

Age and growth of Homonota darwini were studied using skeletochronology on diaphyseal femoral cross-sections. Individual ages were assessed after estimating the resorbed rings in relation to snout-vent length. Snout-vent length and age show a sigmoidal relationship and growth rates show a shift from premature growth to mature breeding when sexual maturity is achieved. The model indicates that sexual maturity in H. darwini is reached at five years in females and nine in males. Species longevity is estimated to be 17 years, which corresponds to a k-selected trait of late maturity and long life expectancy. Once sexual maturity is achieved, size is a poor indicator of age in this species. These results are discussed in terms of behavioural and physiological adaptations of this species to the strong environmental pressures of the Patagonian steppe. They also support the hypothesis that daytime burrow temperatures, which are similar to body temperatures recorded in diurnal lizard species, meet the physiological growth requirements of nocturnal lizard species.