Haliclona (Rhizoniera) rosea (Bowerbank, 1866)

Figure 15

Isodictya rosea Bowerbank, 1866: 282–283 .

Haliclona (Rhizoniera) rosea, de Weerdt 1987: 83, fig. 7.

Material examined: ESFM-POR / 2017-212, S2, 15 –25 m, on stone, 2 specimens; ESFM-POR / 2017-217, S2, 15 –25 m, on Agelas oroides, 1 specimen ; ESFM-POR / 2017-525, S25, 15 –25 m, on stone 3 specimens; ESFM-POR / 2017- 676, S27, 5 –10 m, on stone, 2 specimens; ESFM-POR / 2017-588, S31, 5 –10 m, on stone, 2 specimens .

Description: Specimen is massive, encrusting and 0.6–1 cm in thickness (Figure 15a). Color is brown in after fixation (Figure 15b).

Consistency soft and fragile.Surface is hispid because of projecting spicules.Tubular oscules are slightly elevated (diameter: 0.3–0.8 cm). The ectosomal skeleton is absent. Choanosomal skeletons are formed by multispicular primary lines, which consist of many single spicules. Spongin is scarce and confined to the nodes of the spicules. Spicules include only long and sharp tipped oxeas (125–200 × 3–8 μm) (Figure 15c, d) No microscleres.

Habitat and distribution: This species was previously found under stones, rocks and shells from the infralittoral zone down to 100 m depth (de Weerdt 1987). It is an Atlanto-Mediterranean species (Van Soest et al. 2020). It was reported from the Adriatic (Sarà 1961), Tyrrhenian (Topsent 1925, Sarà 1958), Levantine (Tsurnamal 1968, Idan et al. 2018) and Black Seas (Evcen et al. 2016). This species is a new addition to the marine fauna of the eastern Mediterranean Sea.