Abstract
The Androctonus crassicuda is the most diverse scorpion species in the family of Buthidae, which is endemic to Khuzestan province, Iran. Investigation of the relationship of species by means of a molecular study of specimens is one of the new approaches due to the limitations of the morphological approaches. In the current study, the analysis was based on 32 morphological characteristics of A. crassicuda native to southwest Iran. Moreover, the DNA sequencing of two mitochondrial markers, namely cytochrome oxidase subunit I and 12sRNA loci was performed, and the phylogenetic tree was constructed using maximum likelihood method with 1000 replications using MEGA software (version 7). Based on the results of the phylogenetic tree, A. crassicuda was classified into a monophyletic group. However, the genetic diversity of this species populations was not significant (0.001). The highest and lowest genetic distance of A. crassicuda was compared with the reports obtained in Urmia and west Azerbaijan, Iran. There was a clear divergence between the A. crassicuda isolated from northern and southern areas of Iran. This study showed the importance of geographical and climate features of the region and genetic distance among the populations. The phylogenetic analysis of Androctonus species from other regions showed the highest and lowest genetic distance with A. gonneti (Morocco) and A. amoreuxi (Portugal), respectively. The comparison of the morphological characteristics and morphometric results revealed that metasoma characteristics are important in the identification of A. crassicuda. The results of the analysis of the morphometric values of A. crassicuda were mainly compatible with the phylogenetic trees and supported the traditional morphological classification, thereby presenting a clearly definition of the genera of Androctonus species.