First records of echinoderm species in the checklist of the Algerian coast (Mediterranean Sea), found off Paloma Island

Abstract

The study of echinoderms in the Mediterranean region has generated considerable interest and has led to significant advancements in systematic research. Numerous species have been identified, with 35% of them belonging to the Holothuroidea class. This paper provides pertinent information on the echinoderm fauna of the Algerian coast, specifically focusing on the sampling conducted at Plane Island in western Algeria. Additionally, it includes an updated account of previously recorded species. The recent research findings consist of a total of 288 specimens: 284 ophiuroids and 4 echinoids. The research provides a comprehensive list of all the species identified. Additional species have been discovered at Paloma (Plane) Island. Several of these species have not previously been recorded on the Algerian coastline, such as the pencil urchin Stylocidaris affinis. A map of its distribution has been created to monitor its establishment in the Mediterranean. Our findings show that S. affinis is more abundant in shallow waters ranging from 50 to 150 m. A total of 70 species were documented along the Algerian coast, with the majority belonging to the classes Holothuroidea and Ophiuroidea. The class Crinoidea, however, only counts three species: Antedon bifida moroccana, A. mediterranea, and Leptometra celtica. The majority of species (65.2%) have a distribution that spans the region of the Atlantic Ocean and the Mediterranean Sea. Approximately 33% of species are potentially exclusive to the Mediterranean region, and only one species (1%) is found worldwide. Three echinoderms are now indexed as endangered or threatened in Barcelona’s Appendix II. Moreover, to provide a comprehensive understanding, this study compares the fauna of the Algerian coast with that of adjacent seas.

Keywords

• plane island; algerian basin; endangered species; indigenous species; pencil urchin.