Codium pulvinatum (Bryopsidales, Chlorophyta), a new species from the Arabian Sea, recently introduced into the Mediterranean Sea

Codium pulvinatum sp. nov. (Bryopsidales, Chlorophyta) is described from the southern shores of Oman and from the Mediterranean shore of Israel. The new species has a pulvinate to mamillate–globose habit and long narrow utricles. Molecular data from the rbcL gene show that the species is distinct from closely related species, and concatenated rbcL and rps3–rpl16 sequence data show that it is not closely related to other species with similar external morphologies. The recent discovery of well-established populations of C. pulvinatum along the central Mediterranean coast of Israel suggests that it is a new Lessepsian migrant into the Mediterranean Sea. The ecology and invasion success of the genus Codium, now with four alien species reported for the Levantine Sea, and some ecological aspects are also discussed in light of the discovery of the new species.