Age structure and body size of a critically endangered species, Acanthodactylus harranensis (Squamata: Lacertidae) and its demography

Within reptiles, lizards cover less area across the globe than snakes do. One out of every seven known species of lizards in the world is found only in its type locality. Acanthodactylus harranensis Baran, Kumlutas, Lanza, Sindaco, Ilgaz, Avci & Crucitti, 2005, is one of these species. It is an endemic lizard species in Turkey with a very small area of occupancy and is listed in the critically endangered category (CR) by the IUCN. Here we document the age structure and body size of A. harranensis using skeletochronological methods for the first time and aim to point out current problems and contribute to an understanding of its demography. The mean age of males was found to be significantly higher than that of females. The maximum life span was 10 years in males while it was 9 years in females. The 8-year-old age group contained a higher number of individuals than any other age group. The mean snout-vent length of specimens was not significantly different between the sexes. As in many other lizards, A. harranensis exhibits a low-level male-biased sexual dimorphism. Acanthodactylus harranensis also displayed a considerably bigger body size than other studied lacertids from Sanliurfa province. The data presented in this study may contribute to future conservation efforts for this endangered species.