A skeletochronological study of age in the Caspian pond turtle, Mauremys caspica caspica (Testudines: Geoemydidae) in Golestan Province, Iran

Abstract

We estimated age of the Caspian pond turtle, Mauremys caspicacaspicain Golestan Province with the skeletochronological method, using specimens collected by nets in natural habitats such as ponds and fish farms. In adult M. c. caspica, lines of arrested growth (LAGs) were clearly discernable in the phalangeal and fibula bone cross-sections. The median age of M. c. caspica in the examined Golestan Province population(n = 22) was calculated 9.6 years (4-12) in males (n = 10), and 10.16 years (4-13) in females (n = 12) for the first time. The maximum straight carapace length (SCL2) was in the range of 83.74–221.41 (mean ± SD = 178.39 ± 48.89) mm in males and 103.02–236.84 (193.52 ± 41.32) mm in female specimens. Significant correlation was found between body size and age (p < 0.001). No difference was found in age composition between the sexes. Our study showed that skeletochronological method can be successfully applied to the Caspian pond turtle based on the clear arrest of growth in the hibernation period.