Dictyoceratida Minchin 1900

Figure 26Spongia lamella. a–c different growth forms d grouped oscules in the inner exhalant sponge surface e detail (SEM) of the inhalant apertures f detail of sponge surface with mineral grains enclosed in the slim collagenous layer g skeletal network of a lamina with abundant, cored primary fibres extended between the inner and outer surfaces, and inter-connected by a network of thinner secondary fibres without inclusions.

Figure 27Spongia nitens. a, b dry specimens of the Schmidt’s collection preserved in the Landes Museum Joanneum of Graz c drawing of a living specimen d fibre showing an opaque narrow core e, f different magnification (LM) of the skeletal network, entirely free of mineral inclusions. a, b modified from Desqueyroux-Faundez and Stone (1992) c, d modified from Vacelet (1987) a, b scale bars = 1 cm.

Figure 28Spongia officinalis. a massive large living specimen (ca. 25 cm) showing a finely conulose surface with scattered small oscula b close up of the conulose surface covered by a thin uncellularized collagenous layer (SEM) c magnifications of an inhalant cribrose basal area (SEM) d conules at the spongin skeleton surface (SEM) e twisted surface of secondary fibres (SEM). b, c modified from Pronzato et al. (1998) d, e modified from Pronzato & Manconi (2008) b, d scale bars in mm.

Figure 29Spongia virgultosa. a schematic drawing of the aquiferous system architecture and direction of incurrent and excurrent water flow b low magnification of the skeleton (LM) supporting a funnel c' spongin skeletons of some specimens showing the exhalant funnels (arrows) of the aquiferous system c'' blowup of skeleton skeleton characterised by the absence of cored primary fibres (LM) d exhalant funnel (SEM) e inhalant funnel (SEM). c-e) modified from Pronzato et al. (1998). d, e, f scale bars in µm.

Figure 30Spongia zimocca. a specimens from the sponge market (Djerba, Tunisia) b drawing of the skeletal network at the sponge surface c long and dense conules supported by tips of primary fibres at the sponge surface (LM) d network of uncored secondary fibres e cored primary fibres among uncored secondaries. b modified from Schulze (1879a).

Figure 31Cacospongia mollior. a, b dry specimens from the Schmidt’s collection preserved in the Landes Museum Joanneum of Graz c close up of the sponge surface harbouring several specimens of Chromodoris spp. grazing on epibionts d skeletal network with primary (cored) and secondary (uncored) fibres close to the sponge surface e close up of the skeletal network with primary and secondary fibres (LM). a, b modified from Desqueyroux-Faundez and Stone (1992) d modified from Schulze (1879a) e modified from Pulitzer-Finali & Pronzato (1976) a, b scale bars = 1 cm.

Figure 32Cacospongia proficens. Spongin skeleton with primary fibres cored by alloctonous spicules of Reniera cratera (left) and Reniera mucosa (right). Modified from Pulitzer-Finali and Pronzato (1980).

Figure 33Cacospongia scalaris. a large massive specimen (ca. 35 cm) with finely conulose surface and evident scattered oscula b cored primary fibres perpendicularly connected by secondaries showing a marrow (LM) c drawing of the skeletal network; d) drawing showing radiating primary fibres typically connected by secondaries at right angle (90°). b modified from Pulitzer-Finali & Pronzato (1976) c modified from Laubenfels (1948) d modified from Schulze (1879a).

Figure 34Fasciospongia cavernosa. a large specimen (over 20 cm) from the Kerkennah Islands (Tunisia) b stout spongin fibres in the skeletal network with very scarce inclusions at different magnifications (LM) c granulated (top) and cored (bottom) fibres d internal shape of the typical hollow (from which the species name) e, f rugose surface of skeletal fibres (SEM). c modified from Vacelet (1959) d modified from Schulze (1879a).

Figure 35Hyrtios collectrix. a detail of a fibre tract showing a scanty amount of spongin with a wide variety of mineral debris embedded, including also spicules of many other sponge species b foreign materials embedded in the sponge surface c pictorial representation of a sponge cross section close to the surface with flagellate chambers represented as terminations of a tree-shaped aquiferous system. a–c modified from Schulze (1879b).

Figure 8Dysidea avara. a massive specimen (ca. 5 cm in diameter) showing a large osculum b, c the skeletal network with primary (cored) and secondary (almost uncored) fibres.

Figure 9Dysidea fragilis. a massive specimen (ca. 3 cm in diameter) with an apical osculum; b, c reticulate skeletal network and irregular meshes of primary and secondary fibres with scanty spongin (LM).

Figure 10Dysidea 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.