Latrunculia (Biannulata) algoaensis, Samaai, Toufiek, Janson, Liesl & Kelly, Michelle, 2012

Samaai, Toufiek, Janson, Liesl & Kelly, Michelle, 2012, New species of Latrunculia from the Agulhas shelf, South Africa, with designation of a type species for subgenus Biannulata (Demospongiae, Poecilosclerida, Latrunculiidae), Zootaxa 3395, pp. 33-45 : 40-41

Latrunculia (Biannulata) algoaensis sp. nov.

( Fig. 5 A–C; Fig. 6 AA; Table 1 )

Material examined. Holotype SAM-A24720: Bell Buoy Reef, Algoa Bay, off Port Elizabeth Eastern Cape, South Africa, 33.843° S; 25.816° E, collected by Shirley Parker-Nance on SCUBA, 22 March 2010, 22– 30 m [cross reference number RU-510-3].

Type locality. Algoa Bay, South Africa.

Description. Thickly encrusting to hemispherical sponge, 2.5 cm long x 4 cm wide x 3.5 cm high ( Fig. 5 A), with volcano-shaped oscules, 1 mm wide, up to 2 mm high, and several large, broad, thick-lipped areolate porefields. Texture compressible, colour in life green, in preservative, dark brownish green.

Skeleton. Choanosome an irregular polygonal reticulation of wispy tracts of megascleres, ranging in width from 40–50 μm, forming meshes 140–280 μm wide. A. palisade of microscleres defines the outer ectosome, below which is a paratangential layer of megascleres, 200–350 μm thick, becoming vertical near the porefields ( Fig. 5 B). Numerous anisodiscorhabds are scattered throughout the choanosome between tracts.

Megascleres. Styles ( Tab. 1 ): Smooth, slightly sinuous, centrally thickened and fusiform, often polytylote; 369 (326–384) x 11 (10–12) μm, n=20.

Microscleres. Anisodiscorhabds ( Tab. 1 ; Fig. 5 C): Shaft smooth, 6 μm wide. Basal whorl and manubrium undifferentiated, forming a cuff of large multi-spined protrusions with smooth deeply incised and sculpted spines orientated perpendicular to the axis. Median whorl, 24 μm in diameter, divided into four segments, each segment possessing narrow spearhead-shaped spines, subsidiary whorl, 22 μm in diameter, with narrow, almost rudimentary spines slanted slightly upwards, and divided into segments, each segment possessing five narrow spearhead-shaped spines. Apical whorl and apex form a tuft of smooth sculpted spines; 48 (46–50) μm, n=20.

Ecology. Sponge exposed to considerable wave-surge on rocky platform at 22– 30 m.

Etymology. Named after the location from whence the species was collected.

Remarks. The anisodiscorhabds of L. (B.) algoaensis sp. nov. are reminiscent of those of New Zealand species L. (B.) kaakaariki , L. (B.) duckworthi , L. (B.) wellintonensis and L. (B.) procumbens , in that the basal cuff and other whorls have deeply incised spines that are relatively smooth, sculpted, and are rarely microspined. Those of other South African species are often heavily and consistently spined or serrated ( Fig. 6 W, X). While L. (B.) algoaensis sp. nov. has a similar morphology to L. (B.) gotzi sp. nov. and known species L. (B.) lunaviridis and L. (B.) microoacanthoxea , the former has smooth styles, and is dark green with distinctive broad, thick-lipped areolate porefields.

Figures

FIGURE 5. Latrunculia (Biannulata) algoaensis sp. nov.: A. Holotype SAM-A 24720, preserved specimen, scale = 10 mm; B. Transverse histological section of the body showing the thick ectosome, scale = 100 µm; C. Anisodiscorhabd with smooth, sculpted, vertical, multispined, projections at base, scale = 10 µm.

FIGURE 6. A comparison of anisodiscorhabds and other microscleres of species presently considered valid within subgenera Latrunculia (L.) du Bocage, 1869 (A – N), L. (Biannulata) Samaai et al., 2006 (O – AA), and L. (B.) incertae sedis (AB – AD): A. L. (L.) triverticillata Alvarez et al., 2002; B. L. (L.) fiordensis Alvarez et al., 2002; C. L. (L.) oxydiscorhabda Alvarez et al., 2002; D. L. (L.) cratera du Bocage, 1869; E. L. (L.) bocagei Ridley & Dendy, 1886; F. aciculodiscorhabd of L. (L.) apicalis Ridley & Dendy, 1886; G. aciculodiscorhabd of L. (L.) biformis Kirkpatrick, 1908; H. L. (L.) basilis Kirkpatrick, 1908; I. L. (L.) brevis Ridley & Dendy, 1886; J. L. (L.) palmata Lévi, 1964; K. L. (L.) multirotalis Topsent, 1905; L. L. (L.) ikematsui Tanita, 1968; M. L. (L.) novaecaledoniae Samaai et al., 2006; N. L. (L.) crenulata Lévi, 1993; O. L. (B.) kaakaariki Alvarez et al., 2002; P. L. (B.) duckworthi Alvarez et al., 2002; Q. L. (B.) procumbens Alvarez et al., 2002; R. L. (B.) wellingtonensis Alvarez et al., 2002; S. L. (B.) kaikoura Alvarez et al., 2002; T. L. (B.) millerae Alvarez et al., 2002; U. L. (B.) spinispiraefera Brøndsted, 1924; V. L. (B.) purpurea Carter, 1881; W. L. (B.) lunaviridis Samaai & Kelly, 2003; X. L. (B.) microacanthoxea Samaai & Kelly, 2003; Y. L. (B.) gotzi sp. nov.; Z. L. (B.) kerwathi sp. nov.; AA. L. (B.) algoaensis sp. nov.; AB. L. austini Samaai et al., 2006; AC. L. citharistae Vacelet, 1969; AD. L. oparinae Samaai & Krasokhin, 2002. Reproduced or redrawn from du Bocage (1869), Ridley & Dendy (1886), Topsent (1905), Brøndsted (1924), Lévi (1964, 1993), Alvarez et al. (2002), Samaai & Krasokhin (2002), Samaai & Kelly (2003), Samaai et al. (2006), (not to scale).