Marine biodiversity patterns off Alexandria area, southeastern Mediterranean Sea, Egypt.
The biological marine system in the Mediterranean Sea off Alexandria, Egypt, was investigated to recognise its biodiversity and the relations among "ichthyofauna, invertebrates, and benthic" cover including biota and flora, as well as seabed bathymetry during 2017 using a multi-seasonal surveys by the commercial bottom trawler. Moreover, zooplanktonic community from the water column was also collected to support the picture of the biodiversity in the investigated area. The identified species were 94 fishes, 64 invertebrates, 6 benthic flora, and 304 zooplanktonic species. The ichthyofauna included 5 Chondrichthyes species (5.3% of the fish species), while Osteichthyes fishes were 89 species (94.7%) belonging to 48 families and 72 genera. The most abundant family was Sparidae (13 species). The highest abundance offishes occurred in the summer (68 fish species 72.34%), while the lowest abundance occurred in the spring (49 species, 52.13%). Regarding the demersal and benthic biota, the most abundant phylum was Mollusca (31 species) and represented by three classes (Bivalvia, Cephalopoda, and Gastropoda). Gastropoda was the most abundant class (18 species), while the lowest Phyla was Chordata (1 species of Ascidians) and Annelida (1 species). The number of lessepsian fish species were 17 (18.1%) of the total number of species caught by the bottom trawl net. In addition, this work provided new records Aulopareia unicolor (F): Gobiidae) for the area for first time and considered the second time in Egypt. The benthic flora was represented by 6 species belonging to three phyla (Tracheophyta, Chlorophyta, and Rhodophyta). Sea grasses