Reevaluating sponge diversity and distribution in the Mediterranean Sea

Abstract

The aim of this paper was (1) to update sponge diversity and distribution in the Mediterranean and (2) to re-examine faunal relationships among the Mediterranean areas on the basis of their sponge fauna. The Mediterranean demosponge faunal list was updated to 629 species by taking into consideration recent data from previously poorly studied areas. The species lists of 14 Mediterranean areas were compared on the basis of their sponge species richness, species composition, and taxonomic relatedness of species using multivariate analyses and diversity measures, such as PD, Delta?, and Lambda?. The 14 Mediterranean areas examined for their diversity and affinities were assembled into four major zoogeographic groups: the northwestern, northeastern, the central zone, and southeastern areas. Richest in species numbers were the areas belonging to the two northern groups. The species richness comparisons and similarity analyses performed at the generic level showed that it can be safely used as a surrogate for sponge species diversity in the Mediterranean. The results of this study showed that the simple traditional division of the Mediterranean Sea into a western, central, and eastern basin cannot reliably describe the distribution of sponges in the area. Thus, the W to E faunal decline previously presented for several faunal groups shifts to a general NNW-SSE pattern when one examines separately the northern and the southern parts of the traditional basins. This gradient seems to be in agreement with differences in key environmental variables, such as latitude, salinity, temperature, and water circulation, besides the typically examined distance from Gibraltar.

New and rare sponges from the deep shelf of the Alboran Island (Alboran Sea, Western Mediterranean)

“…A total of 631 demosponges sensu lato: (i.e., Demospongiae + Homoscleromorpha) have been listed for the Mediterranean (Voultsiadou 2009;Calcinai et al 2013; the present study). Interestingly, the bottoms around the Alboran Island host 194 demosponge species (Table 6), which means about 30.4% of the total Mediterranean demosponge fauna.…”

Shedding light on an East-Mediterranean mesophotic sponge ground community and the regional sponge fauna

“…Consequently, it is vital to study these unique habitats in order to better understand their role in the local ecosystem and determine how best to protect them. Voultsiadou (2009) analyzed the spatial distribution of the Mediterranean sponge fauna and revealed a north-north-west to south-south-east gradient in sponge diversity, rather than the commonly accepted west-east gradient (Voultsiadou, 2005a;Coll et al, 2010;Mouillot et al, 2011;Coll et al, 2012). Nonetheless, we hypothesized that this gradient might not be as steep as described, and that the Levant's low sponge biodiversity could be the result of lower research efforts in the Eastern-Mediterranean region (Van Soest et al, 2012).…”

“…The Levantine Sea sponge diversity had been regarded until now as species-poor compared to that of other parts of the Mediterranean Sea (Voultsiadou, 2009;Coll et al, 2010;Van Soest et al, 2012). This has been mainly attributed to the physicochemical conditions of the Levantine Sea, which are less suitable for the Atlantic species that inhabit the western and northern parts of the Mediterranean.…”

“…Whereas sponge fauna of the Western Mediterranean has been studied quite thoroughly, data on the Levant fauna are scarce (see Carteron, 2002;Perez et al, 2004;Voultsiadou, 2005aVoultsiadou, , 2009Vacelet et al, 2007;Vacelet et al, 2008;Evcen & Cinar., 2012;Van Soest et al, 2012;Topaloglu et al, 2014). Specifically, current knowledge on the sponge fauna of the Mediterranean coast of Israel is outdated, limited to the shallow waters, and derived from several old publications, including surveys of the benthic fauna in the bay of Haifa conducted in the 1950s (Levi, 1957;Gottlieb, 1959).…”

Diversity patterns and zoogeography of the Northeast Atlantic and Mediterranean shallow-water sponge fauna

“…Pansini & Longo (2003), followed by Voultsiadou (2009), were the first to provide a comprehensive account of the diversity and biogeography of the Mediterranean sponges. Both studies recognized the contribution of the Atlantic Ocean to the diversity patterns seen in the Mediterranean, but the lack of an analysis combining data from both areas has obscured our understanding of the relationship between them.…”