We studied a population of sand lizards (Lacerta agilis) near the northern edge of the species’ range in coastal Sweden. We captured, marked, released and recaptured 98 adult female lizards over 5 years. Hatchlings from 146 laboratory-incubated clutches (1279 eggs) from field-caught gravid females were measured, weighed, marked and released at the study site. Female sand lizards usually laid only a single clutch of 4 to 15 eggs each year, but varied considerably in the time of year at which they laid their eggs. Oviposition dates shifted between years depending on weather (basking opportunities), but the relative timing of oviposition was consistent within a given female from year-to-year. The first females to oviposit each year were large animals in good physical condition, that had grown rapidly in previous years. ‘‘Early’’ clutches were larger than ‘‘later’’ clutches, had higher hatching success, and tended to have higher post-hatching survival rates. Offspring from early clutches were larger than ‘‘later’’ hatchlings, and differed in body proportions (probably because seasonal changes in maternal temperatures directly modified offspring phenotypes). Overall, our study documents several strong correlates of the timing of oviposition, and suggests that variation in this trait among females has strong fitness consequences, perhaps related to maternal ‘‘quality’’. The correlations we observed between oviposition date and other traits that have been invoked as determinants of hatchling survival in reptiles (e.g., hatchling size, body shape, opportunities for multiple mating by the mother) suggest that hypotheses advocating simple causal connections between these traits and hatchling success should be viewed with caution.

We studied growth and longevity of Lacerta agilis from a sample (34 adults and 2 small-sized juveniles) of a population living at high altitude in north-western Italy using skeletochronological method. Snout vent length (SVL) mean of males did not significantly differ from that of females although the latter were in average bigger (SVL ± SD, males: 69.3 ± 7.1 mm, n = 11; females: 73.9 ± 9.7 mm, n = 22; Mann- Whitney U-test, U = 1.76, P = 0.077). Age ranged from 2 to 4 years (mean age ± SD = 2.3 ± 0.2) in males and from 2 to 3 years in females (mean age ± SD = 2.59 ± 0.5 years). Age mean did not significantly differ between the sexes (Mann-Whitney U-test, U = 1.35, P = 0.174). The two juveniles were 30 and 32 mm in SVL and both were 1-2 months old. In both sexes, a significant positive correlation between SVL and age was recorded although weakly significant for males (Spearman’s correlation coefficient, males: rs = 0.70, P = 0.05; females: rs = 0.75, P < 0.001). Von Bertalanffy growth curves well fitted to the relationships between age and SVL and showed a different profile between males (asymptotics size, SVLmax = 81.9 mm; growth coefficient, k = 0.63) and females (SVLmax = 100 mm; k = 0.40). Results indicate that individuals of L. agilis studied by us are short-living when compared with other populations of the same species.