Desmacella polysigmata

Rützler, Klaus, Piantoni, Carla, Van, Rob W. M. & Díaz, Cristina, 2014, Diversity of sponges (Porifera) from cryptic habitats on the Belize barrier reef near Carrie Bow Cay, Zootaxa 3805 (1), pp. 1-129 : 68

Desmacella polysigmata van Soest, 1984

Synonymy and references. Desmacella polysigmata van Soest, 1984a: 138, fig 54, pl. 9: 3.

Material. USNM 1229065, Curlew Bank, forereef cave, 21 m; C. Piantoni and M. Parrish col. 21 Aug 2012.

External morphology. Cushion, about 4 cm in diameter and 2 cm thick. Surface partially covered by a web of filamentous red algae and a thin coralline algal crust. There are a few circular, low and porous incurrent papillae and oscula, 3–5 mm in diameter. The sponge is brittle and shows a cavernous interior where broken. The color in life is grayish white.

Skeleton structure. In the ectosome, styloid megascleres placed tangentially, a few perpendicular; numerous microscleres (sigmas). In the choanosome, megascleres in bundles and arranged in halichondrioid fashion, spaces in between densely filled with sigmas.

Spicules. Long, slender styles, many with strongylote modifications (rounded at both ends: 550–880 x 12–18 (639 x 14) Μm; sigmas I: 36–55 (46) Μm; sigmas II: 13–16 (15) Μm.

Ecology. Only one specimen was collected, from a forereef cave in 21 m; a second one from the same habitat was found as overgrowth of Prosuberites carriebowensis . Van Soest (1984a) reported the type found among muddy sand off Barbados, 100 m.

Distribution. Caribbean Sea.

Comments. The megascleres in our specimen are somewhat longer and thinner that those of the type, but all other morphological characteristics agree well with the type description.