New records, conservation status and pectoral fin description of eight shark species in the Egyptian Mediterranean waters

M. Shaban, Walaa; A. M. El-Tabakh, Mohamed

doi:10.21608/ejabf.2019.57896

New records, conservation status and pectoral fin description of eight shark species in the Egyptian Mediterranean waters

Document Type : Original Article

Authors

10.21608/ejabf.2019.57896

Abstract

For a taxonomical purpose, the present study described and analyzed the pectoral fin shape and measurements of sharkspecimens, collected from the Egyptian Mediterranean Sea waters at Alexandria, during the period from May 2017 to June 2018. Morphology and morphometric fin characters were used taxonomically to differentiate between shark species via photo program analysis. After confirming the identification of sharks, a list of shark species in the Egyptian Mediterranean waters was given with emphasize on new record species as well as the conservation status of each species.
Results showed that the collected specimens belong to eight species from different six families belonging to four orders. Species-list of sharks in this study including; Heptranchias perlo, Hexanchus griseus, Squalus megalops, Centrophorus uyato, Oxynotus centrina, Squatina squatina, Isurus oxyrinchus and Isurus paucus. By comparing the present findings with the previous studies,three shark species out of these eight species were considered as new records in the Egyptian Mediterranean waters. These new records are Heptranchias perlo, Squalus megalops and Isurus paucus.According as the global assessment of the IUCN (2018) red list, Heptranchias perlo and Hexanchus griseus are reported as near threatened species; while Oxynotus centrina considered as vulnerable species. Isurus oxyrinchus and Isurus paucus mentioned as endangered species. However, Squatina squatinais critically endangered. On the other hand, data was insufficient to state the situation of Squalus megalops and Centrophorus uyato.
The morphological aspects of pectoral fins, for these eight shark species, were greatly varied in shape that proved the potential capability to use this new technique as an important identification and classification tool. The statistical analysis of morphometric ratios also supports this proposition and shows a significant variance between investigated species. Our study attempted to add more update information on shark pectoral fin morphological and dimensional scaling.

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