Petrosia (Petrosia) weinbergi (Van Soest, 1980 )

Campos, Maurício, Mothes, Beatriz, Eckert, Rafael, Van, Rob W. M. & Soest, 2005, Haplosclerida (Porifera: Demospongiae) from the coast of Maranhão State, Brazil, Southwestern Atlantic, Zootaxa 963, pp. 1-22 : 17-18

Petrosia (Petrosia) weinbergi (Van Soest, 1980)

Figs. 10 A–D

Petrosia weinbergi Van Soest, 1980: 75 –76, Fig. 27, pl. XII Figs. 3–4

Petrosia weinbergi ; Lehnert, 1993: 48 –49, Figs. 16, 74–76, tab. 11; Lehnert & Van Soest, 1998: 93.

Examined material. MCNPOR 5035, 184 m, 01°03’25”S – 43°30’36”W, 15.VI.1999 (fragment deposited in ZMAPOR 17913).

Material studied for comparison. Petrosia weinbergi (Van Soest, 1980) : ZMAPOR 12756, material deposited in MCNPOR 6250 (det. Rob Van Soest).

Description. Massive fragment ( Fig. 10 A): 5.5 cm long, 5.0 cm width, 3 cm height. Smooth surface, rough to the touch; oscules circular (only one observed), 0.3–0.4 cm in diameter. Preserved material with very hard consistency, colour dark gray.

Skeleton. The ectosome consists of a single spicule network with nodal spongin ( Fig. 10 B). This network is supported by thick spicule tracts, forming rounded meshes (350– 570 µm in diameter). Choanosome with rounded thick meshes at uppermost portion; beneath these meshes the skeleton is gradually filled by many spicules in confusion, less spongin ( Fig. 10 C).

Spicules. Oxeas ( Figs. 10 D): three size categories, some curved, slightly swollen. Blunted extremities, acerate forms may occur. All three categories presents the same features and variations, but are perfectly distinguishable by their sizes: Oxea I: 160– 242. 4 – 290 / 10– 12. 4 –15 µm; oxea II: 77.5– 105. 3 –145 / 5– 7. 8 –12.5 µm; oxea III: 55– 67. 5 –75 / 2.5– 4. 9 –7.5 µm.

Remarks. This is the first record of the species outside the Caribbean. The three size categories of swollen oxeas distinguish it from other West Indian species, and the comparision with type material confirms our identification. Our sample has slightly larger dimensions compared to those presented by Van Soest (1980), mainly in the spicule thickness.

Distribution. Mexico to Curaçao (Van Soest, 1980; Lehnert, 1993; Lehnert & Van Soest, 1998). Brazilian coast: Maranhão (present study).

Figures

FIGURE 3. Haliclona (Halichoclona) lernerae sp. nov. A, sample (scale: 3 cm). B, tangential view of ectosome (scale: 200 µm). C, perpendicular section of choanosome (scale: 300 µm). D, line drawings of oxeas (scale: 50 µm).

FIGURE 4. Amphimedon caribica (Pulitzer­Finali, 1986). A, sample (scale: 3 cm). B, tangential view of ectosome (scale: 200 µm). C, perpendicular section of choanosome (scale: 300 µm). D, line drawings of oxeas (scale: 50 µm).

FIGURE 10. Petrosia (Petrosia) weinbergi (Van Soest, 1980). A, sample (scale: 2 cm). B, tangential view of ectosome (scale: 300 µm). C, perpendicular section of choanosome (scale: 300 µm). D, line drawings of oxeas (scale: 50 µm).