SEXTUAL DIMORPHISM IN Gloydius halys (VIPERIDAE: CORTALINAE) OF CENTRAL ALBORZ MOUNTAINS OF IRAN

We described the taxonomic relationship of pitvipers population of Central Alborz mountains of Iran. The morphological data on Gloydius halys snakes; 8 female and 11 male snake from three Lar, Taleghan and Gachsar regions of Central Alborz Mountains Iran, showed sexual dimorphism. The results of independent samples test showed that body length (SVL) in male was 48 ±10 cm that was more than SVL in female, 43 ± 6 cm (P≤0.05), head length (HL) in male was 2.2 ± 0.3 cm and more than females, 1.9±0.2 cm at P=0.01. The mean height of the head (HH) was 0.95 ± 0.04 cm and more than 0.52 ± 0.70 cm, respectively (P = 0.04). The size of the Sq front in male snakes was 22.6 ± 0.8 and 21.7 ± 0.7 in female (P = 0.02), Ciruocular right in male was 5.6 ± 0.5 and in female snake 5.13 ± 0.3 (P = 0.02), the size of the CG trait for male and female was respectively 9.6 ± 0.8 and 11.1 ± 0.8 at P = 0.007, the size of the ventral scales number for males was 153.7 ± 4.2 and for females 148 ± 5.9, P = 0.03, and the subcaudal for male was 37.18 ± 1.5 and females 32.7±1.9, (P≤0.05). Also, in the multivariate analysis of the main components, the separation of male and female samples is evident. In the geographical variation, there was a significant difference in the seven characters between different populations, and in the hierarchical clustering analysis, the separation of three populations of Lar, Taleghan and Gachsar was observed. Result reveals the geographical differences in Gloydius halys of Central Alborz mountains of Iran and tow populations from Lar and Takht –E-Solyman have close relations and somehow distinct from halys of Gachsar population and dimorphism was observed in female and male of all three populations.