Spider (Araneae: Araneomorphae) diversity in Annaba Province, Northeastern Algeria

Spiders, as predatory arthropods, play essential roles in ecosystem equilibrium and serve as bioindicators. To contribute to the understanding of spider diversity in northeast Algeria (Annaba province), a survey of spider fauna was conducted in both forest and urban sites over two consecutive years using the "hand collecting" method. A total of 879 adult spiders (681 females and 198 males) were identified, representing 25 families and 67 species. The Salticid Plexippus paykulli (Audouin, 1826) was the most abundant species, with 127 specimens collected. The most abundant families were Salticidae and Araneidae, with counts of 171 and 139 individuals, respectively. The Shannon-Weaver index varied from 2.17 to 3.68 bits across the different sites, while evenness values ranged from 0.60 to 0.75. This study significantly expanded the known spider species in Annaba province from 96 to 138.