Skeletochronological assessment of age in the Persian mountain salamander, Paradactylodon gorganensis (Clergue-Gazeau and Thorn, 1979) (Caudata: Hynobiidae) from Golestan Province, Iran

Abstract

Lines of arrested growth (LAGs) were assessed in the Golestan Province population of the critically - endangered museum specimens of Persian mountain salamander, Paradactylodon gorganensis (Clergue-Gazeau and Thorn, 1979) from Northeastern Iran using skeletochronology. LAGs were clearly discernable in the tibia and femur bone cross-sections and could be interpreted for age determination. The number of LAGs in the sampled Golestan Province population (n=29)was found to be 8-11 (9.75 1.13 years) in males (n=12), 7-13 (9.26 1.98 years) in females (n=15) and 7 and 8 (7.50 0.70 years) in two unknown sex specimens for the first time.The snout-vent length (SVL) was 90.20 - 119.38 (103.85 10.48) mm in males, 77.60 - 135.00 (105.96 15.89) in females and 108.00 and 123.00 mm in unknown sex specimens. It was not found significant correlation between body size and age (P > 0.05). Although limited in sample size, the data suggest that males with ages over eleven years are absent in the fixed specimens studied. Our study showed that skeletochronological method can be successfully applied to Iranian P. gorganensis based on the clear arrest of growth in the hibernation period, as previously observed in other species in subtropical regions.