TY - JOUR T1 - Cosmopolitism in sponges : the "complex" Guitarra fimbriata with description of a new species of Guitarra from the Northeast Atlantic JF - Scientia marina Y1 - 1993 A1 - Boury-Esnault, N A1 - Pansini, M A1 - Uriz, MJ SP - 367 EP - 373 KW - ATLANTIQUE NORD-EST KW - COSMOPOLITE SPECIES KW - GUITARRA KW - POECILOSCLERIDA AB - A new species of the genus Guitarra (G. laplani) is described from the Gibraltar region (Northeast Atlantic). The type material of the species, G. fimbriata Carter and G. voluta Topsent revised by scanning electron microscopy, and the results compared with descriptions from the literature. The results suggest G. voluta is a valid species and provide grounds for distinguishing two groups of specimens among those described under the name G. fimbriata. The first group is formed by North Atlantic deep specimens matching the holotype of G. fimbriata and is mainly characterized by tornostrongyloid megascleres, the presence of two categories of placochelae, and microspined pseudoisochelae. The second group, with an Indo-Pacific littoral distribution, would correspond to G. bipocillifera Broensted, characterized by oxeas tapering to long points as megascleres, one category of placochelae, and distinctive spiny isochelae. These results illustrate a new example of what was previously believed to be a cosmopolite species, that a thorough reexamination has shown to be a species complex, thus restricting the distribution of G. fimbriata s.s. to the North Atlantic. VL - 57 N1 - Recent advances in ecology and systematics of sponges. Eds: Uriz,M-J; Rützler,K ER -