Latrunculia (Biannulata) purpurea Carter, 1881

Samaai, Toufiek, Gibbons, Mark J. & Kelly, Michelle, 2006, Revision of the genus Latrunculia du Bocage, 1869 Porifera: Demospongiae: Latrunculiidae) with descriptions of new species from New Caledonia and the Northeastern Pacific (, Zootaxa 1127 (1), pp. 1-71 : 52-54

Latrunculia (Biannulata) purpurea Carter, 1881

( Figs 1R, 5F , 6H2, 7, 8B; Tables 2 & 3)

Latrunculia purpurea Carter, 1881 , PL. XVIII, FIG. 5A–C ; Latrunculia purpurea ; Kelly­Borges and Vacelet, 1995, pg 497. Negombata purpurea ( Carter, 1881) ; Hooper and Wiedenmayer, 1994, pg 249; Negombata purpurea ( Carter, 1881) ; Alvarez at al., 2002, PG 152, TABLE 1 & PG 178.

Holotype material. Not examined. Holotype BMNH 1954.3.9.455, specimen destroyed during war, Latrunculia purpurea Carter 1881 , PL. XVIII. FIG. 5 , A–C.

Additional material. Not examined, BMNH 1954.3.9.458 (slide). Originally identified as L. corticata .

Other material examined. QM 310897 (cross ref. Q66C 2463­S and Ts 16), Horseshoe Reef 3 km of Margaret Brock Lighthouse, Cape Jaff , 36º 56.80'S, 139º 35.00'E, depth 18 m, collected by AIMS/NCI, February, 1989 . MKB 1335 , Horseshoe Reef 3 km of Margaret Brock

Lighthouse, Cape Jaff, 36º 56.80'S, 139º 35.00'E, depth 18 m, collected by AIMS/NCI, February , 1989. QM 310897 (cross ref. Q66C 2463­S and Ts 123) Horseshoe Reef 3 km of Margaret Brock Lighthouse , Cape Jaff , 36º 56.80'S, 139º 35.00'E, depth 18 m, collected by AIMS/NCI, February , 1989. QM 311064 (cross ref. Ts 153 and Q66C 2883­Y), Split Rock ; Eclipse Island , Albany, W.A, 35º 11.20'S, 117º 52.40'E, depth 20 m, collected by AIMS/NCI March 1989 .

Description. The sponge is flat, compressed, thin, circular, cake­like or fungiform. The voucher specimens are cake­like and thickly encrusting ( Fig. 8B). Surface smooth, finely hispid, and generally fold­like with no visible oscules or mammiform areolate porefields on the surface. Ectosome thin, not separable from underlying choanosome. Texture soft, spongy, compressible, and leathery on the surface. Colour in life dark green; in preservative, choanosome dark chocolate brown and ectosome dark brown. Carter (1881) described the fresh holotype as "ragged" and "proliferous" on the upper surface and texture spongy being "dark brown­purple" in colouration (from Carter 1881)

Skeleton. The choanosomal skeleton is a confused very irregular polygonal­meshed reticulation formed by wispy tracts of aniso­oxeas with no distinction between the primary and secondary tracts ( Fig. 5F ). The tracts range in width from 100–250 m in thickness and form meshes that are 273 m wide. Within the inner choanosome, the tracts are more robust and compact but diverge towards the surface where they become more vertically arranged. Scattered throughout the choanosome, between the tracts, are numerous anisodiscorhabds and abundant interstitial megascleres. The surface of the ectosome is lined with an erect layer of anisodiscorhabds. Beneath the discorhabds in the ectosome is a thin paratangential layer of densely interlocking megascleres, approximately 150 m wide.

Spicules. Megascleres (Fig. 6H2): aniso­oxeas are smooth and thin, fusiform at ends, 324 (288–336) x 5 (5) m, n=20 [Holotype 330 x 6 m (from Burton's unpublished catalog housed in BMNH)]. Microscleres ( Fig. 1R): anisodiscorhabds, the manubrium is a reduced vertically arranged spinose base followed by a smooth long, slender cylindrical shaft 12 m long and 2 m wide. The median whorl is reduced, circular and horizontally arranged with spines slanted upwards, similar in diameter to the subsidiary and apical whorl. The subsidiary whorl is more or less slanted upwards. The spines of the apical whorl are more or less horizontally arranged ending in a crown­like tuft of vertically arranged spined projections, 32 (31–36) x 2.4 (2.4) m, n=20 [Holotype 30 m long (from Burton's unpublished catalogue housed in BMNH)].

Substratum, depth range and ecology. Sheer rock walls; crevices and gullies, Boulders. Associated with Ecklonia other algae and sponges. Depth range: 18–20 m

Geographic distribution ( Fig. 7 ). South Australian Basin, Australia;

Remarks. All species previously identified within the genus Latrunculia have had either straight or polytylote styles, with a few species having strongyloxeas (see above). This species is unique in that it possesses aniso­oxeas as megascleres. Carter (1879) and (1881) described two species under the name Latrunculia ( L. purpurea and L. corticata ), which possess oxeas as megascleres. Ridley and Dendy (1887) questioned the validity of these oxeate sponges and doubtfully placed them in the genus Latrunculia . Kelly­Borges and Vacelet (1995) in their review of Diacarnus and Negombata placed Latrunculia corticata in the genus Negombata after examination of the holotype. They also suggested that Latrunculia purpurea was a valid species of Latrunculia based on Carter's description: "sponge being flat, compressed, circular, thin, cake like or fungiform, brown purple in colour, with a ragged and proliferous upper surface". Kelly­Borges and Vacelet (1995) also indicated that the microsclere compliment of Latrunculia purpurea is typical of Latrunculia ­"the two inner spined discs are disposed towards one end of the spicule, and is disposed on the upper side arranged perpendicular on the darker surface of the sponge".

Alvarez et al. (2002) however, after examination of the type material (BMNH 1954.3.9.458) of L. purpurea Carter , suggested that this species was incorrectly assigned to Latrunculia , based on the then current diagnosis of Latrunculia . During the course of the same year, Samaai and Kelly (2002) emended the definition of Latrunculia to include species with oxeote megascleres. As, it is currently perceived, based on a combination of characters, including the ontogeny of the anisodiscorhabds, we conclude that this is a valid species of Latrunculia . Structurally the discorhabd complement is very different to L. spinispiraefera , L. citharistae and L. kaikoura (see Fig. 1) and are smaller on average than the species in the subgenus Biannulata from New Zealand (see Table 3).

Figures

FIGURE 5. Photomicrographs of choanosomal architectures: A. Latrunculia ikematsui Tanita 1968; B. Latrunculia oxydiscorhabda Alvarez et al. 2002; C. Latrunculia triverticillata Alvarez et al. 2002; D. Latrunculia austini sp. nov.; E. Latrunculia citharistae Vacelet 1969; F. Latrunculia purpurea Carter 1881.

FIGURE 7. Worldwide distributions of Latrunculia (Biannulata) species. Distributions of A) Latrunculia spinispiraefera Brøndsted, B) Latrunculia citharistae Vacelet, C) Latrunculia purpurea Carter, D) Latrunculia oparinae Samaai and Krasokhin; E) Latrunculia lunaviridis Samaai and Kelly; F) Latrunculia microacanthoxea Samaai and Kelly; G) Latrunculia kaakaariki Alvarez et al.; H) Latrunculia duckworthi Alvarez et al.; I) Latrunculia procumbens Alvarez et al.; J) Latrunculia wellingtonensis Alvarez et al., 2002; K) Latrunculia kaikoura Alvarez et al.; L) Latrunculia millerae Alvarez et al.; M). Latrunculia austini sp. nov.