Farkhondeh Sayyadi - Department of Biology, Faculty of Science, Razi University, ۶۷۱۴۹۶۷۳۴۶ Kermanshah, Iran
Nasrullah Rastegar-Pouyani - Department of Biology, Faculty of Science, Razi University, ۶۷۱۴۹۶۷۳۴۶ Kermanshah, Iran
Mehri Azadbakht - Department of Biology, Faculty of Science, Razi University, ۶۷۱۴۹۶۷۳۴۶ Kermanshah, Iran
Khosrow Chehri - Department of Biology, Faculty of Science, Razi University, ۶۷۱۴۹۶۷۳۴۶ Kermanshah, Iran

The morphology and structure of the hemipenis play a significant role in the recognition of species, and could be an excellent indicator of the phylogenetic relationships among male taxa. The hemipenes have value in distinguishing taxa. Laudakia nupta and Paralaudakia caucasia are sympatric in Kalekan Neck (Northeastern regions of Kermanshah Province, 34° 42’ N, 47° 17’ E, Elevation: 1880 m). In this study, we investigated and compared hemipeneal structure of Laudakia nupta and Paralaudakia caucasia as character displacement in sympatric populations. Hemipenes of eight adult collected males (four from each species) were removed and examined morphology and histology. The results indicate that there are differences in the structure of their hemipenis between two species. In Laudakia nupta, hemipenes are black organs, approximately smooth tubular with groove and split in tips but in Paralaudakia caucasia, hemipenes are pink organs, bilobed, branched and bifurcated structure. It seems that the difference between the structure of hemipenises in two species can be a factor in the separation of male species in Kalekan Neck (Northeastern regions of Kermanshah Province). The structure of hemipenis is potentially important for distinguishing male species.

hemipenis, character displacement, Laudakia caucasica, Laudakia nupta, sympatric populations