Halisarca dujardini Johnston, 1842

Manconi, Renata, Cadeddu, Barbara, Ledda, Fabio & Pronzato, Roberto, 2013, An overview of the Mediterranean cave-dwelling horny sponges (Porifera, Demospongiae), ZooKeys 281, pp. 1-68 : 43-44

Halisarca dujardini Johnston, 1842 Fig. 36

Halisarca dujardini Johnston, 1842: 192.

Description.

Growth form encrusting, few mm thick and few cm in diameter. Consistency jelly-like or softly colloidal. Surface smooth with small oscular tubes and not evident inhalant apertures. Colour in vivo pale yellow to dark yellowish, sometimes with more or less dark blue tonalities. Absence of horny skeleton. Flagellate chambers radially arranged around the aquiferous system canals, elongated and typical of the genus (25 µm in diameter, 60-150 µm in length).

Habitat.

Cave, Posidonia oceanica meadow, coralligenous community, rocky/sandy bottom, frequently epibiotic on rhodophyte algae, Ircinia spp. and Smittina cervicornis (Pallas, 1766). Bathymetric range 5-100 m.

Mediterranean Caves.

Blava, Calamars, La Catedral, J 1, Meda petita, Petita de la Vaca caves (Balearic Sea); Troc, Bagaud caves (Gulf of Lions); Bergeggi Cave (Ligurian Sea); Secca delle Formiche-Vivara, Gaiola caves (Central Tyrrhenian Sea) ( Sarà 1961a; Boury-Esnault 1971; Pulitzer-Finali and Pronzato 1976; Pulitzer-Finali 1977; Bianchi et al. 1986; Bibiloni et al. 1989; Uriz et al. 1992; Harmelin et al. 2003; Pronzato and Manconi 2011).