Dysidea avara (Schmidt, 1862) Fig. 8

Spongelia avara Schmidt, 1862: 29.

Description.

Growth form usually irregularly massive (2-4 cm large, 1-2 cm thick) and commonly lobate. Specimens with large size (15-20 cm in diameter) and long digitations (5 cm) not infrequent. Colour constantly light rose-violet. Surface free of foreign debris, conulose with a regular fibrous network interconnecting apices of conules; conules large (3-6 mm high, 2-6 mm apart, sometimes clubbed). Oscules (4-10 mm in diameter) apical on digitations with a very delicate transluscent collar (2-4 mm) sometimes evident in living specimens; inhalant apertures (30-50 µm in diameter) scattered . Choanosome lax with ovoid choanocyte chambers (70 µm in diameter). Skeleton as a three-dimensional network of irregular polygonal meshes (100-800 µm) with primary fibres extremely variable in size (60-300 µm) constantly and heavily filled by foreign material; secondary ones (20-40 µm) with light and laminated spongin almost regularly free of debris or with scattered grains. Reproduction reported in June.

Habitat.

Cave, coralligenous community, artificial reefs, rocky/muddy/detritic bottom, lagoon, Posidonia oceanica meadow. Bathymetric range 1-100 m.

Mediterranean caves.

Blava, Meda Petita, Petita de la Vaca, Blue, Misidacis caves (Balearic Sea); Galatea*, Falco*, Bisbe* caves (Sardinian Sea); Béar, Troc, Endoume caves (Gulf of Lions), Bergeggi Cave (Ligurian Sea); Taccio Vecchio 1 Cave-Lampedusa* (Sicily Channel); Sifone Cave (Ionian Sea); Croatian, Columbera, Stražica caves (Northern Adriatic Sea); Sorrentino, Spido, Bue Marino caves (Southern Adriatic Sea); Farà Cave (Aegean Sea) (Boury-Esnault 1971; Pouliquen 1972; Pulitzer-Finali and Pronzato 1980; Bibiloni et al. 1984a, b; Bianchi and Morri 1994; Corriero et al. 2000; Novosel et al. 2002; Martì et al. 2004; Faresi et al. 2006; Turon et al. 2009; Denitto et al. 2010; Pronzato and Manconi 2011; Bakran-Petricioli et al. 2012; Cadeddu 2012; Gerovasileiou and Voultsiadou 2012).