Contribution to the Study of the Biodiversity of Patellidae in the Gulf of Skikda (Northeast Algeria)

This study aims to inventory the different species of limpets and analyze the fauna and flora colonizing the rocky substrate of a part of the Algerian eastern coast. In 2022, we collected 189 limpets from five sites in Skikda bay, identifying six species of the Patellidae family within the genus. Patella: P. caerulea, P. rustica, P. vulgata, P. ulyssiponensis, P. intermedia, and the endangered Mediterranean species P. ferruginea. The dominant plants identified belong to six orders: Ulvales, Cladophorales, Bryopsidales, Gigartinales, Ralfsiales, and Bangiales, while the dominant animals are distributed in seven orders: Vetigastropoda, Decapoda, Neogastropoda, Isopoda, Sessilia, Scalpelliormes, and Camarodonta. The most abundant limpet species is Patella rustica, while Patella ferruginea and Patella ulyssiponensis are the rarest. The Shannon–Weaver diversity index for the five studied sites is H' = 1.44 bits, indicating comparable biodiversity richness. Additionally, the presence of nine trace metal elements (TME) was measured in the flesh of the most abundant species at each site, revealing contamination by Cd, Pb, Hg, and Ni, while the values of Cu, Zn, and Fe do not exceed the IAEA-407 standards.