Scleritoderma sp.

Schlacher-Hoenlinger, Monika A., Pisera, Andrzej & Hooper, John N. A., 2005, Deep-sea “ lithistid ” assemblages from the Norfolk Ridge (New Caledonia), with description of seven new species and a new genus (Porifera, Demospongiae), Zoosystema 27 (4), pp. 649-698 : 655-661

Scleritoderma sp.

( Figs 2B ; 6 ; 21 )

MATERIAL EXAMINED (see Table 1). — Kaimon-Maru, 380 m ( QM G318716).

DESCRIPTION

Growth form

Small pillow to subspherical/ovoid sponge with a broad base and a flattened upper surface which bears a large pore area with numerous, evenly distributed openings. The examined specimen is 1.2 cm high and 4.5 cm wide.

Colour

Beige in etoh.

Oscules

Numerous, evenly distributed, very small (0.1- 0.3 mm diameter). The larger pores are mainly scattered on one side of the sponge.

Texture

Hard, stony.

Surface ornamentation

Rough to touch, slightly uneven with canals and tiny pores.

Ectosomal skeleton

No special distinction.

Choanosomal skeleton

Choanosomal skeleton consists of rhizoclones, which are branched and are covered with numerous branched spines, with tips divided into small- er spine-like processes. Large openings on the surface of the choanosomal skeleton are present.

Megascleres

Desmas spinose rhizoclone, with short and blunt rays: 220-300 µm/30-40 µm.

Oxeas large, protruding from around oscular openings, always broken.

Microscleres

Acanthorhabds (curved, common): 45.8-51.0 × 2.24 µm.

Sigmaspires also present.

REMARKS

This specimen possibly belongs to a new taxon, but was dead on collection, with only some microscleres preserved; its specific determination remains uncertain. The presence of acanthorhabds excludes it from Leiodermatium and places it within the genus Scleritoderma , which is also confirmed by the typical appearance of the ectosomal spicules and the presence of sigmaspires.

Schlacher-Hoenlinger M. A. et al.

Due to the degraded state of the animal only few sigmaspires were detected. Its pillow or subspherical shape makes it different from other so far described species of Scleritoderma .

Scleritoderma flabelliforme Sollas, 1888 ( Figs 2D ; 7 ; 22A, B )

Scleritoderma flabelliformis Sollas, 1888: 316 , pl. 35: 26-50. — Lévi F Lévi 1989: 47, fig. 15, pl. 2: 3.

HOLOTYPE. — Ki Island , Indonesia, S of West Papua ( BMNH 1891.5 .4.10).

MATERIAL EXAMINED (see Table 1). — Épon ge, 508- 541 m ( QM G318641). — Antigonia, 540 m ( QM G318658). — Banc 1, 458- 680 m ( QM G318664).

DESCRIPTION

Growth form

Norfolk Ridge specimens were consistently massive, flabelliform sponges, or tree-like digitate

New “lithistids” (Porifera, Demospongiae) from New Caledonia masses with nodes, whereas Sollas (1888) and Lévi F Lévi (1989) described the species as highly polymorphic, ranging from flabellate/digitate forms to cup-ear- to vase-shaped or curved plates. Present specimens are approximately 4 to 5 cm high and 2.5 to 5 cm wide, with a 1.5 to 2.5 cm broad base.

Colour

Dirty white to grey in etoh.

Oscules

Oscules are distributed at the tops of the nodes, and/or one or both sides are covered with small pore-like, raised oscules (0.3 mm diameter).

Texture

Hard, stony.

Surface ornamentation

Smooth.

Ectosomal skeleton

Ectosomal spicules are acanthostrongyles/rhabds which form a dense tangential layer on the surface. Choanosomal skeleton

The very dense choanosomal skeleton with large opening on the surface is composed of thorny rhizoclones.

Megascleres

Desmas spinose, thorny rhiziclone, with short, blunt rays: 400-500 µm/30-45 µm.

New “lithistids” (Porifera, Demospongiae) from New Caledonia

Microscleres

Microrhabds (curved): 61.6-101 × 5.66-7.72 µm. Sigmaspires (spinose): 8.25-11.5 × 1.86-2.22 µm.

REMARKS

The material described here differs morphologically from the holotype in being massive digitate or flabelliform, and in having oscules located mostly at the top of the branches, but it strongly resembles specimens of S. flabelliforme from the China Sea described by Lévi F Lévi (1988). Furthermore, this species is described in the literature as being highly polymorphic, ranging from flabelliform, encrusting, massive with nodes to cup- to vase-shaped (Pisera F Lévi 2002a). In its spicule characteristics and size these specimens closely resemble the holotype, and there is no hesitation in assigning this material to this taxon.

Figures

FIG. 2. — A, Aciculites orientalis Dendy, 1905; B, Scleritoderma sp.; C, S. camusi Lévi & Lévi, 1983; D, S. flabelliforme Sollas, 1888; E, Corallistes australis n. sp.; F, Herengeria vasiformis n. sp.; G, H. auriculata Lévi & Lévi, 1988. Scale bars: 1 cm.

FIG. 6. — Scleritoderma sp.; A, outer surface of the choanosomal skeleton with canal openings leading to oscules; B, choanosomal skeleton; C, details of choanosomal skeleton of rhizoclones; D, details of articulation between choanosomal desmas; E, details of choanosomal skeleton of rhizoclones; F, detail of spinose rhizoclone. Scale bars: A, 1 mm; B, E, 200 µm; C, D, F, 100 µm.

FIG. 21. — A-D, Aciculites orientalis Dendy, 1905; A-C, heads of strongyles; D, strongyles; E, F, Scleritoderma sp.; E, heads of strongyles; F, strongyles. Scale bars: A-C, F, 10 µm; D, 100 µm; E, 5 µm.

FIG. 7. — Scleritoderma flabelliforme Sollas, 1888; A, outer surface of the choanosomal skeleton with large openings; B, choanosomal skeleton; C, details of choanosomal skeleton of rhizoclones; D, details of choanosomal skeleton of rhizoclones; E, outer surface with crust of curved microstrongyles; F, detail of outer surface with crust of curved microstrongyles. Scale bars: A, 1 mm; B, 500 µm; C, 100 µm; D, E, 200 µm; F, 50 µm.

FIG. 22. — A, B, Scleritoderma flabelliforme Sollas, 1888; A, acanthorhabds; B, sigmaspires; C, D, S. camusi Lévi & Lévi, 1983; C, acanthorhabds; D, sigmaspires. Scale bars: A, C, 20 µm; B, D, 2 µm.