Biogeography and distribution of Elasmobranches based on biodiversity indices in the Persian Gulf and Oman Sea

The present study aimed to the biodiversity of Chondrichthyes and distribution of this group of aquatic animals in the Persian Gulf and Oman Sea using biodiversity indices and finally, the maps were ploted using the GIS software. Data collection was carried out from October to December 2018 using bottom trawler by Ferdows from Sistan and Baluchestan and Hormozgan provinces waters in the Persian Gulf and Oman Sea. A total of 4014 specimens were caught in the study area, of which 245 specimens belonged to 10 species and 4 families of sharks and 3769 specimens belonged to 21 species and 12 families. The results showed that Margalef species richness index varied from zero to 1.82 for sharks and from zero to 2.65 for batoids. Also, the Pielou’s evenness index varied from 0.43 to 1 for sharks and from 0.11 to 1 for the batoids. Also, the Shannon index varied from zero to 1.9 for sharks and zero to 1.86 for batoids. The Shannon Diversity Index distribution for sharks only showed a range of 54 to 56 degrees longitude (range south of Qeshm Island to Bandar-lengeh) as a hotspot compared to the rest of the study area. On the other hand, the distribution of this index showed two points, range from 57 to 59 degrees longitude (Sirik to Meydani) and of 53 to 55 degrees longitude (Kish Island to Qeshm Island) as hotspots for the presence of batoids.