Phylogenetic Relationships of Scorpion Compsobuthus matthiesseni Based on Sequences of Internal Transcribed Spacer 2 Gene from Khuzestan Province, Iran

Buthidae family includes scorpions with highly potent venom such as Compsobuthus matthiesseni is important due to the prevalence of scorpion stings in Khuzestan Province, Iran. Morphometric comparison of males and females (n=5 each) showed that the body and carapas of the females were longer and wider (32.57±0.23 mm and 3.75±0.22 mm, respectively) than those of males (28.89±0.25 mm and 3.55±0.12 mm, respectively). From the seven specimens of C. matthiesseni scorpion, 410-bp gene fragments of ribosomal internal transcribed spacer 2 were amplified by polymerase chain reaction. The specimens of CM1 and CM2 (isolated from Baghmalek, Khuzestan) were in the same group with bootstrap values of 87%. Nevertheless, CM4 and CM3 (isolated from Shushtar and Bidroobe, Khuzestan) with bootstrap values of 73% and 62% were separated from the two specimens of Baghmalek, respectively. The two specimens CF3 and CM5 (isolated from Masjed Soleiman, Khuzestan) with bootstrap values of 88% were placed next to each other in a separate group. CF2 was separated from the rest of the specimens with a bootstrap value of 54%. Out of the seven scorpions that were examined, six specimens (CM1, CM2, CM3, CM4, CM5, and CF3) showed the greatest similarity between 1.1% and 4%. However, the genetic distance between CF2 and the rest of the specimens was at the range of 10.8-14.2%. It can be concluded that all C. matthiesseni scorpions from Khuzestan Province belonged to one species; nonetheless, differences were observed within the species, especially in the case of CF2, which might be intraspecies.