Chondrosia corticata Thiele, 1900

Calcinai, Barbara, Belfiore, Giuseppe, Pica, Daniela, Torsani, Fabrizio, Palma, Marco & Cerrano, Carlo, 2020, Porifera from Ponta do Ouro (Mozambique), European Journal of Taxonomy 698, pp. 1-56 : 5-6

Chondrosia corticata Thiele, 1900

Fig. 2

Chondrosia corticata Thiele, 1900: 67 , pl. 3 fig. 21.

Material examined PONTA DO OURO • a single fragment of about 5 ×2× 1.5 cm; 26°49′17.512″ S, 32°53′42.521″ E;

Kev’s; 23.4 m deep; 3 Feb. 2017; Cerrano leg.; PO7 .

Description

The live sponge is massive ( Fig. 2A ). The large, protruding oscules in the live specimen ( Fig. 2A ), collapsed in the preserved sample. The color varies from dirty white to brown; the sides exposed are darker than other parts. The specimen preserved in alcohol shows the same color variation, with a lighter interior. The surface is smooth, with numerous foreign materials. The consistence of the sponge in spirit is soft and compressible. The fragment is cavernous with a thick cortex of about 0.7–2 mm ( Fig. 2 A–B), covering a soft pulpy choanosome, cream-colored ( Fig. 2A ).

Remarks

The absence of spicules and of an organic skeleton, the parameters usually used to discriminate sponge species, makes it difficult to distinguish between species of Chondrosia Nardo, 1847 leading some scientists to consider certain species such as C. reniformis (the type species of the genus) as cosmopolitan ( Lazoski et al. 2001).

This genus includes 10 accepted species and one ( C. pendulus Gammil, 1997 ) under inquirendum ( Van Soest et al. 2019). Among the species from the Indo-Pacific Area, C. chucalla de Laubenfels, 1936 differs from the studied material in the thinner cortex (250 µm) and in the amount of foreign material described as “enormous”. Chondrosia debilis Thiele, 1900 has been recorded in this ecoregion ( Lévi 1958; Vacelet & Vasseur 1965, 1971, 1976), but it differs in the characteristic wrinkles of the surface. Chondrosia ramsayi Lendenfeld, 1885 differs in its color, varying from bluish black to dark brown, and its rough surface. The inner part is dark brown. Chondrosia reticulata (Carter, 1885) is rich in foreign materials and doesn’t show a clear cortex. Chondrosia rugosa Hentschel, 1909 has a surface covered by papillae and wrinkles and a slightly thicker (0.7–1.5 mm) cortex.

The described specimen fits with Chondrosia corticata in the general morphology, color, and mainly in the presence of a thick cortex, embedded with foreign spicules and debris, that is peculiar in this species ( Thiele 1900).

This is the first record for the Western Indian Ocean.

Figures

Fig. 2. Chondrosia corticata Thiele, 1900. A. Specimen (PO7) in situ. The arrow points a fresh cut showing the sponge’s thick ectosome. B. Histological section showing the thick ectosome and the cavernous choanosome.