An overview of the Mediterranean cave-dwelling horny sponges (Porifera, Demospongiae) Author Manconi, Renata Author Cadeddu, Barbara Author Ledda, Fabio Author Pronzato, Roberto text ZooKeys 2013 281 1 68 http://dx.doi.org/10.3897/zookeys.281.4171 journal article http://dx.doi.org/10.3897/zookeys.281.4171 1313-2970-281-1 Dysidea incrustans (Schmidt, 1862) Fig. 10 Spongelia incrustans Schmidt, 1862: 29. Description. Growth form encrusting (3-8 mm thick). Consistency fragile. Colour light grey to pale violet. Surface reticulate, conulose showing the internal aquiferous system in transparency. Conules 1-3 mm high, 3-5 mm apart. Oscules (5-7 mm) scattered, with a transparent collar. Skeletal network irregular with meshes (200-600 µm in diameter) formed by ascending primary fibres (70-90 µm in diameter) cored of foreign material, and secondary fibres (5-30 µm in diameter) generally lacking inclusions. Habitat. Cave, rocky bottom, artificial reefs, Posidonia oceanica meadow, lagoon, also. Frequently as encrusting patches also on other sponges or epibiotic on Pinna nobilis . Bathymetric range 1-100 m. Mediterranean Caves. Galatea* Cave (Sardinian Sea); Lerici Cave (Ligurian Sea); Mago, Mitigliano caves (Central Tyrrhenian Sea); Taccio Vecchio 1 Cave-Lampedusa* ( Sicily Channel); Gamberi*, Gymnasium* caves (Ionian Sea) ( Pulitzer-Finali and Pronzato 1976 , 1980 ; Pansini et al. 1977 ; Pulitzer-Finali 1977 ; Pansini and Pronzato 1982 ; Pronzato and Manconi 2011 ; Cadeddu 2012 ). Figure 10 Dysidea incrustans . a close up of a large (ca. 20 cm) encrusting specimen showing scattered small oscula and visible inhalant pores b reticulate skeleton with a secondary network of slimmer fibres almost free of inclusions c main fibres cored of foreign material supporting the conules at the sponge surface.