Latrunculia (Latrunculia) triverticillata Alvarez 2002

Latrunculia (Latrunculia) triverticillata Alvarez et al., 2002

(Figs 1L, 2, 3F, 5C; Tables 2 & 3)

Latrunculia triverticillata Alvarez et al., 2002, PG. 170, FIG. 3D, 9 Latrunculia spinispiraefera; Bergquist 1961, PG. 189, FIG. 13

Holotype material. Not examined NZOI H 799, NIWA collection.

Additional paratype material. NZOI P­1269; NZOI 1270, Niwa collection; Latrunculia spinispiraefera Bergquist 1961, Chatham Rise, 396 m, Sta. 6 (CM unregistered).

Other material examined. T. S 15545 (cross ref. Ts 462), Tas., D'Entrecasteaux Channel, Tinderbox, E. of boat ramp, depth 1–3 m, collected by K.L. Gowlett­Holmes on the 14/07/ 1991. T. S 15544 (Ts 464), Tas., Tasman Penin., Shag Rock Bay, depth 15–17 m, collected by K.L. Gowlett­Holmes, 9/10/1994. NZOI stn M780 (cross ref. Ts 55) unidentified sponge in NIWA collection, 44º 36.35'S, 167º 52.05'E, depth 40 m, collected on the 01/04/1981.

Diagnosis. Small, semispherical sponge (Fig. 3F) with cylindrical­shaped oscules, which are divided into 2–3 chambers, and numerous thin truncated lipped and subglobular thick crater­like areolate porefields that are covered with a distinct poral pellucid membrane. Colour in life is dark green; in preservative, choanosome dark brown and ectosome dark chocolate brown. Styles are fusiform, 333 (300–355) x 11 (9–12) m, n=20 [Holotype 377 (326–413) x 6 m (after Alvarez et al. 2002); Bergquist voucher 350 x 6 m (after Bergquist 1961)] (see Table 3). Anisodiscorhabds (Fig. 1L) with a simple manubrium, above which is a basal whorl similar in diameter to the median and subsidiary whorls; the whorls are denticulate with 4 groups of spines. The apical whorl is simple and also spined. Anisodiscorhabd length 45 (43–46) x 7 (7) m, n=20 [Holotype 42 m long (after Bergquist 1961)]. The choanosomal skeleton consists of a firm, well developed but irregular polygonal­meshed reticulation and towards the surface the spicules become denser and tend to be vertically arranged (Fig. 5C). The surface of the ectosome is lined with an erect layer of non­interlocking anisodiscorhabds. The ectosome of Voucher specimen T. S 15545 consists of a clear, thick band of collagenous mesohyal, 130–273 µm thick, at the base of which is a thin band of paratangential styles 20 µm deep (Fig. 5C). The thickness of this paratangential layer differs in voucher specimen T. S 15544 and the holotype (NZOI H­799), which has a thick paratangential layer of densely interlocking megascleres, approximately 180 m wide in T. S 15544 and 200–450 m in the holotype. The sponge are frequently found on flat rocky surfaces in New Zealand as compared to off Tasmania where it is found on rocky substrata, under rocky overhangs and rocks; depth range 1–396 m (after Alvarez et al. 2002).

Geographic distribution (Fig. 2). Tasmania; New Zealand

Remarks. This species is clearly differentiated from other New Zealand species by Alvarez et al. 2002 by the morphology of the anisodiscorhabds, and colouration in life and the surface morphology.