Variations in age, size at maturity and gestation duration among two neighbouring populations of the alpine salamander (Salamandra lanzai)

We describe the age structures of two neighbouring terrestrial salamander p opulations. The skeletochronological method was also used on larvae in uter o and on new-born individuals. The age of adults was 8-24 years in populati on A, while males reached maturity at 3-5 years old and the youngest female s were 6 years old in population B. Males and females from population B wer e also larger than those in population A. For the first time, lines of arre sted growth (LAGs) were also found in the humerus of intra-uterine larvae a nd new-born individuals, indicating that young can spend up to 3 years in u tero (population B) and up to 4 years (population A) before hatching. Growt h of adults (fitted by the Bertalanffy model) also exhibited differences in growth coefficient (k) and mean asymptotic length (SVLmax) between sexes a nd populations. Local climatic conditions differed between the two areas of these populations and we hypothesize that the number of rainy days directl y influences foraging during the short period of activity (< 3 months), lea ding to a delay in age at maturity, smaller length and growth rate, and inc reased gestation duration in the drier environment. The discussion is focus ed on proximate environmental influences on the variation of length and ass ociated life-history traits in ectotherms, especially in terrestrial salama nders.