Morphological aspects of dorsal fin for eight shark species with special reference to the first records in Egyptian Mediterranean waters, Alexandria, Egypt

M. Azab, Ahmad; M. M. Khalaf-Allah, Hassan; M. H. Sarhan, Moustafa; A. M. El-Tabakh, Mohamed

doi:10.21608/ejabf.2019.48551

Morphological aspects of dorsal fin for eight shark species with special reference to the first records in Egyptian Mediterranean waters, Alexandria, Egypt

Document Type : Original Article

Authors

10.21608/ejabf.2019.48551

Abstract

The present study aimed to describe the dorsal fin measurements used to differentiate between some shark species in Egyptian Mediterranean waters. A total of 43 specimens of sharks were seasonally collected from the commercial catch of the Mediterranean Sea land fish markets in Alexandria, during the period from May 2017 to June 2018. Morphometric characters of dorsal fin were recorded for each specimen. Many photos had been captured for each shark specimen to be processed by Image J software to calculate different ratios of morphological aspects for dorsal fin.
Results showed that the collected specimens belong to 8 species (Heptranchias perlo, Hexanchus griseus, Squalus megalops, Centrophorus uyato, Oxynotus centrina, Squatina squatina, Isurus oxyrinchus and Isurus paucus) and three species of them (Heptranchias perlo, Squalus megalops and Isurus paucus) are a new record in the Egyptian Mediterranean waters. The morphological aspects of dorsal fin in these eight shark species were greatly varied in shape.
The morphological aspects of studied shark species proved the potential capability of this method for shark species identification. The statistical analysis of morphometric ratios showed significant variances between investigated species. Our study attempted to add more update information on shark dorsal fin morphological and dimensional scaling.

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