New Data on Two Subspecies of Mesobuthus eupeus, the Most Medically Important Scorpion Species in Northwestern Iran

Scorpions are among the most medically important arthropods in Iran, particularly northwestern areas. To date, five scorpion species, i.e. Mesobuthus eupeus, Mesobuthus caucasicus, Androctonus crassicauda, Hottentotta saulcyi, and scorpio maurus, have been identified. The family Buthidae is responsible for most cases of scorpionism in Iran. The Mesobuthus eupeus species belong to this family and is commonly distributed from Turkey to China, including Iran. Among these species, Mesobuthus eupeus is regarded as the most medically important species and responsible for most cases of envenomation in this area. Morphological differences between some species collected in the study area have been reported. The present study, thus, aimed to identify the subspecies of Mesobuthus eupeus in northwestern Iran. Scorpions were captured in the summer months from 37 localities in three northwestern provinces in Iran: West Azerbaijan, East Azerbaijan, and Ardabil. Scorpion collection was carried out using rock rolling and ultraviolet methods. A total of 376 specimens of Mesobutus eupeus (177males and 199 females) were collected and identified as Mesobuthus eupeus (98.4%) and Mesobuthus eupeus philippovitschi (1.6%). Owing to the findings of our study, M.e.philippovitschi has been added to the scorpion fauna of northwestern parts of Iran for the first time. Unlike M.e. eupeus which is widely distributed from plains to mountainous regions, M.e.philippovitschi has limited distribution and is found mostly along the borders with neighboring countries. This subspecies is the most medically important and most prevalent one in the region. The findings of the present study also provide the basis for future consideration of regional antivenom production for this medically important species.