N. Gholinezhad - Faculty of Marine Science and Technology, North Tehran Branch, Islamic Azad University (IAU),Tehran, Iran
A. Ashja Ardalan - Faculty of Marine Science and Technology, North Tehran Branch, Islamic Azad University (IAU),Tehran, Iran
M. Malek - School of Biology, College of Science, University of Tehran, Tehran, Iran

Gastropods are considered as the main molluscs of rocky shores and often show marked zonation patterns both horizontally and vertically. Biodiversity and distribution of gastropods were investigated at ۸ stations on rocky shores of Qeshm Island during the coldest and warmest months January and  August, respectively, in ۲۰۱۸. In the present study, ۳۵ gastropod species were identified. The highest frequency of gastropod (۵۵۰±۳۴۵) was observed at S۲ station (Tula ۲) and the lowest one was observed at S۸ station (Naz Island) (۲۷۳±۸۳.۷۰). Planaxis sulcatus was found as the dominant species at all stations (%۵۵.۷۶). The results of the ۳-way permutational (MANOVA) test showed that the species’ structures of the gastropod community are different at various stations and during sampling months. The results of the nMDS test confirmed these differences in the structure and species composition of the gastropod population during two months. The highest diversity (Shannon index: ۳.۱۳) and species richness (Margalef index: ۴.۵۳) was observed at the S۲ station and the lowest diversity (Shannon index: ۲.۷۳, Margalef index: ۳.۰۳) was observed at the S۸station. According to the results of the SIMPER test, the highest percentage of participation in Bray-Curtis dissimilarity between the two months in summer and winter and at different sampling stations in terms of species density was related to Planaxis sulcatus. The structure of gastropod population at the studied stations can be influenced by the factor of seasonal changes.

Biodiversity, Spatial Distribution, Rocky shores, Qeshm Island, Persian Gulf