Age structure and growth pattern in two populations of the golden-striped salamander chioglossa lusitanica (caudata, salamandridae)

Abstract

We studied age structure and growth in two populations of the golden-striped salamander, Chioglossa lusitanica, in northern Portugal by cohort analysis and skeletochronology. Lines of Arrested Growth (LAG) deposited during the larval phase could be distinguished from LAG deposited after metamorphosis. One or two LAG were found in larvae, with counts corresponding to age in years as predicted from larval size distributions. Post-metamorphic modal age was 5 to 6 years and longevity was 8 years. Von Bertalanffy growth curves for males and females from both populations were different from one another. Sexual maturity was reached 4 to 5 years after metamorphosis and corresponded with a snout-vent length of 43-44 mm in both sexes. A tendency was observed for females to be older than males. Mature females were on average larger than mature males. Larval growth was higher in spring than in winter and differed between populations and years. The population in which larvae grew relatively slowly was characterized by large young adults and vice versa, perhaps reflecting contrasting aquatic and terrestrial feeding conditions. The knowledge here presented is important for the better understanding of the population dynamics and ecological and conservation requirements of the golden-striped salamander.