Neoschrammeniella castrum, Schlacher-Hoenlinger & Pisera & Hooper, 2005

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 : 678-679

Neoschrammeniella castrum n. sp. ( Figs 3D ; 15 ; 29 )

HOLOTYPE. — Épo nge seamount, Norfolk Ridge, 24°54’72”S, 168°21’87”E, 508-541 m, RV Alis, 23.VI.2001, Warén dredge, coll. T. Schlacher ( MNHN DCL 3905 , a fragment of the holotype in QM [G318564s).

ETYMOLOGY. — Named for the massive and thick walled gross morphology ( castrum, Latin for fort, walled town, stronghold).

OTHER MATERIAL EXAMINED (see Table 1). — Épo nge, 539-545 m (QM G318586).

DESCRIPTION

Growth form

Massive, short, cup-shaped sponges with a broad base, thick walls and round cup openings and rounded margins. Specimens are approximately 3 cm high and 3 cm wide with an approximately 2.5 cm broad simple base.

Colour

Beige to light brown in etoh.

Oscules

Not visible.

Texture

Hard, stony.

Surface ornamentation

Smooth.

Ectosomal skeleton

Ectosomal skeleton contains smooth dichotriaenes perpendicular to the surface and abundant microscleres. Microscleres at the surface are numerous forming a crust and consist of microspinose spirasters with short, blunt rays.

Choanosomal skeleton

Choanosomal structure composed of strongly tuberculated, irregular dicranoclones, resulting in a very dense skeleton. Choanosomal microscleres are streptasters/spirasters with long pointed rays.

Megascleres

Dicranoclone desmas are very thick, and are densely covered with mushroom-shaped tubercles, which are clearly subdivided into smaller callosities: 520-700 µm/70-85 µm.

Dichotriaenes smooth; conical, curved rhabdome and conical rays of cladome: 457-693 µm long × 293-350 µm diameter (cladome).

Microscleres

Streptasters (spirasters) with long pointed rays: 85.3-114 × 69.1-90.2 µm.

Massive spirasters with short blunt rays: 12.4- 14.6 × 6.95-8.57 µm.

REMARKS

As for the new Neoschrammeniella species described above ( N. norfolkii n. sp.), this new species undoubtedly belongs to the genus Neoschrammeniella on the basis of its characteristic microscleres and desmas, but differs considerably in shape from the type species. The new species N. castrum n. sp. is similar in shape to N. norfokii n. sp. but differs in having only two types of microscleres instead of three types, and in having more massive but shorter spirasters with a blunt rays, which are much less regularly developed. It differs also in having tubercles on the desmas which are further subdivided into smaller callosities, while N. norfolkii n. sp. has smooth tubercles.

Family PLEROMIDAE Sollas, 1888 DEFINITION. — Polymorphic lithistids with megaclone (usually smooth) choanosomal desmas and ectosomal dichotrianes; sometimes additionally anatriaenes; microscleres are spirasters or amphiasters, microxeas and/or styles (Pisera F Lévi 2002c).

Figures

FIG. 3. — A, Isabella mirabilis n. gen., n. sp.; B, Neoschrammeniella moreti (Lévi & Lévi, 1988); C, N. norfolkii n. sp.; D, N. castrum n. sp.; E, Anaderma rancureli Lévi & Lévi, 1983. Scale bars: 1 cm.

FIG. 15. — Neoschrammeniella castrum n. sp.; A, outer surface of the choanosomal skeleton; B, details of outer surface of the choanosomal skeleton; C, D, details of choanosomal desmas. Scale bars: A, 1 mm; B, 500 µm; C, 200 µm; D, 100 µm.

FIG. 29. — Neoschrammeniella castrum n. sp.; A-E, choanosomal spirasters with long pointed rays; F-K, massive ectosomal rhabdlike spirasters; L, M, ectosomal dichotriaene; N, cladome of ectosomal dichotriaene. Scale bars: A-E, 20 µm; F-K, 5 µm; L-N, 100 µm.