A Contribution to the Thermal Ecology of Lacerta agilis bosnica Schreiber, 1912 (Reptilia: Lacertidae)

Thermal ecology is critical for the study of the biology of every living species. Accordingly, body temperature affects the performance and fitness of animals. In the particular case of ectotherms, this effect is further reinforced since they rely on environmental conditions for heat adjustment. Current air and substrate temperatures are among the crucial sources of regulation for their body heat. In the case of lizards, various behavioral techniques are employed to insure their thermoregulation and therefore survival. The aim of the present study is to identify the basic thermal preferences of Lacerta agilis bosnica, including possible age and sex related variations. This lacertid subspecies is endemic to the high mountains across the Balkan Peninsula and limited between 1100 and 2200 m above sea level. Our results revealed highest body temperature of 35.9°C and lowest – of 19.5°C both measured in adult females. We calculated the average thermoadaptation index (Ti) of 1.27 for all individuals. Furthermore, the positive correlations of lizard body temperature (Tb) compared to air (Ta) and to substrate (Ts) temperatures were highest in immature males, while lowest - in adult males. We found statistically significant differences between the age/sex groups within Tb and Ta. Regarding Ts and Ti, the tests did not show significant differences between the groups. We concluded that L. agilis bosnica is a taxon adapted to low ambient temperatures. With this discovery we contributed to the exploration of the understudied subspecies Lacerta agilis bosnica.