Diversity
The results showed that 37 species of Crustacea were recorded in the western Libyan coast. They belong to four orders: Isopoda, Decapoda, Amphipoda, and Balanomorpha (Table 1). The number of sampled species varied between 14 (Tellil) and 29 (EL-Shajara) (Table 2). In previous studies twenty species were recorded in Libya (Sogreah 1977), 125 species of amphipods (Ortiz and Petrescu 2007). In similar studies in North Africa, 133 species of amphipods were recorded in Tunisia (Zakhama-Sraieb et al. 2009), Diwara et al. (2008) recorded 44 species in North Tunisia, while, in the eastern coast of Algeria, 45 species of Crustacea were recorded in Annaba (Frehi and Derbal 2005).