Asymmetry study of meristic characters of head in Schmidt's whip snake (Dolichophis schmidti) and large whip snake (Dolichophis jugularis) in north of Iran

Developmental disturbances in reptiles may lead to asymmetry of morphological characters such as asymmetry in scale numbers and skeletons and change from normal status. Therefore, it was studied morphological disturbances and asymmetry of meristic characters of two non-venomous colubrid snakes, Schmidt's whip snake (Dolichophis schmidti) and large whip snake (Dolichophis jugularis) in north of Iran. In this research, 13 meristic characters of head region of 33 specimens of Dolichophis schmidti (16 males, 6 females, 5 juveniles and 6 unidentified sexes) and 28 specimens of Dolichophis jugularis (15 males, 7 females, 5 juveniles and 1 unidentified sexes) were studied under binocular. Specimens collected from west Azarbaijan, east Azarbaijan, Alburz, Mazandaran, Golestan, Chaharmahal  va Bakhtiari, Lorestan, Khorasan Razavi and Zanjan provinces and belonging to zoology museum of Golestan university (ZMGU), Gonbad Kavoos  university and personal collections. Results revealed that specimens of Dolichophis schmidti were asymmertric in supralabials (3 specimens), infralabials (5 specimens), anterior subocular (1 specimen), postocular (1 specimen), temporal (7specimens), prenasal (2 specimens) and loreal (1 specimen). Also it was asymmetric left and right sides of supralabials (3 specimens), infralabials (7 specimens), anterior subocular (1 specimen), temporal (5 specimens) and loreals (3 specimens) in Dolichophis jugularis. These morphological asymmetric characters in Dolichophis schmidti and Dolichophis jugularis may be the result of embryonic disturbances, dominant homozygote and genetical changes.