Petrosaspongia nigra Bergquist, 1995

Uriz, María - Jesús & Cebrian, Emma, 2006, Presence of the Indo – Pacific genus Petrosaspongia Bergquist, 1995 (Porifera: Demospongiae) in the Atlantic with description of a new species (P. pharmamari n. sp.), Zootaxa 1209, pp. 61-68 : 63-64

Petrosaspongia nigra Bergquist, 1995

pictures.

Description

External features

Massive–lobulose with an unarmoured microconulose surface. Each conule ends in a thin projecting fibre ( Fig. 1 A). Consistency stony, incompressible. Oscules spread on the surface, 1–2.8 mm in diameter. Colour blackish outside, beige inside, in alcohol.

Skeleton

Reticulate with a dense network of secondary fibres forming meshes 80–225 m in diameter. They form fenestrate plates when they join the primary fibres.

Primary fibres: 355–790 m in thickness, strongly cored by foreign debris ( Fig. 1 B)

Secondary fibres: 20–80 m ( Fig. 3 A), laminated and completely free of foreign debris. ( Fig. 1 B–C & Fig. 3 C). Through SEM, the surface of the secondary fibres appears rippled in a longitudinal direction ( Fig. 1 C).

Tertiary fibres: Very thin, rare.

Choanosome containing abundant sand and other foreign materials ( Fig. 1 D).

Distribution: Southwest Pacific region, New Caledonia islands, from 10 to 38 m depth.

Note. The re–examination of the holotype allowed us to measure the skeletal elements, and our results provide larger fibre diameters (particularly for the primary fibres) from those given by Bergquist (1995).

Figures

FIGURE 3. Light microscope pictures of the secondary skeleton of (A) P. nigra, (B) P. pharmamari, (C) laminated secondary fibres of P. nigra, (D) laminated secondary fibre of P. pharmamari.

FIGURE 1. P. nigra: (A) holotype preserved in alcohol, (B) primary fibres (double arrow) with foreign debris and a network of secondary fibres (arrow), (C) laminated secondary fibres with longitudinal ripples, (D) choanosome with considerable amounts of foreign debris (arrows). SEM