Demosponges of the red coral bottoms from the Alboran Sea

Abstract

This paper deals with a study of demosponge fauna inhabiting the red coral facies on the circalitoral bottoms surrounding the Alboran Island (Western Mediterranean, Alboran Sea). A total of 58 species were recognized, after examining a total of 107 sponges. Two of these species are new to science (Plakinastrella mixta sp. nov. and Leptolabis megachela sp. nov.) and another one (Rhaphidectyon spinosum Topsent) is recorded for the first time in the Mediterranean. Some other specimens collected belonging to poorly known species, such as Erylus papulifer Pulitzer-Finali, Isops anceps (Vosmaer), Spongosorites flavens Pulitzer-Finali and Timea cumana Pulitzer-Finali, are described briefly. Two controversial specimens, assigned to Microciona spinarcus and Plocamilla cf. novizelanica, are also described and discussed. A high degree of epibiosis and abundance of rare species were the major features characterizing the material studied.

Keywords :

• Demospongiae
• Corallium rubrum
• systematics
• Alboran Sea