Geodia cf. barretti Bowerbank, 1858

Periasamy, Rengaiyan, Cárdenas, Paco, Kurian, Palayil John, Ingole, Baban & Samaai, Toufiek, 2023, Is the North Atlantic Geodia barretti (Porifera, Tetractinellida, Geodiidae) present on the Southwest Indian Ridge?, Zootaxa 5380 (5), pp. 461-474 : 464-467

Geodia cf. barretti Bowerbank, 1858

Figure 2 ; Table 1

Geodia barretti, Bowerbank, 1858: p. 290 .

Cydonium barretti, Gray, 1867: p. 548 .

Sidonops barretti, von Lendenfeld, 1903: p. 101

Geodia simplicissima, Burton, 1931: p. 2

Material examined. NCPOR /HYD-CIO/0011, unnamed seamount 265 km southwest of Rodrigues Triple Junction , Southwest Indian Ridge, - 26.4835°S, 67.41°E, depth 2236 m, modified benthic sledge, collected by Dr. Baban Ingole, 11 April 2019; UPSZMC 190804, two spicule slide preparations of the same specimen .

Comparative material. Geodia barretti , holotype, BNHM 1877.5 .21.1399, South side of Vikna Island , North- Trøndelag, Norway, 183 m, coll. R. McAndrew; Geodia hentscheli , holotype, ZMB Por 7549, North of Spitsbergen, 81°20′N, 20°30′E, 1000 m, 11 th August 1898; Geodia garoupa , holotype, MNRJ 7349 , Campos Basin , RJ, Brasil, 22.366°S, 39.893°W, 1130 m, 7 Feb. 2003, coll. RV Astro Garoupa .

Description. A small, damaged presumably previously subspherical sponge ( Fig. 2A ), 20 × 10 × 30 mm in diameter, growing on a rock ( Fig. 2A ). The sponge is firm and hard but compressible. Most of the surface has been removed during collection but it appears prickly with spicules protruding 1 mm ( Fig. 2A ) where the ectosome layer is still visible. Oscules and pores are not visible. Cortex 0.8–1 mm thick where visible ( Fig. 2B ). Colour in life beige, with cortex whitish; in ethanol whitish beige.

Skeleton ( Fig. 2B ). Ectosomal skeleton with oxeas II protruding the surface ( Fig. 2B ). Layer of strongylasters followed by a layer of sterrasters. Triaene cladomes support the cortex. Oxyasters and sterrasters are present in the choanosome.

Spicules ( Fig 2C–I ; Table 1 ). Megascleres. Oxeas I ( Fig. 2D ), large, usually bent, 2991 (2461–3774) μm × 58 (46–71) μm. Oxeas II ( Fig. 2D ), straight, 672 (518–897) μm × 9.5 (8–11) μm. Ortho- to dichotriaenes ( Fig. 2C ) with a wide size range, most are dichotriaenes, rhabdome with tapering tips and commonly with one to two ectopic branches, bent up ( Fig. 2C ), rhabdome: 2934 (1824–3494) μm × 114 (92–148); cladome structures vary, with the clad tips either bent down or bent inside or straight, clad tips are commonly slightly dichotomized, orthoclad, 250 (181–345) μm; protoclad, 170 (118–233) μm; deuteroclad, 201 (115–265) μm. Anatriaene, one found on slide UPSZMC 190804, rhabdome broken,> 1264 µm × 30 µm; cladome fairly opened, clad 136 µm.

TABLE 1. (Continued)

Microscleres. Oxyasters ( Fig. 2I ), one category, approximately 13 spiny slender actines, 28 (25–31) μm in diameter. Sterrasters ( Fig. 2E, F ), spherical to oval (most are spherical), 106.7 (95–120)/111.6 (100–121) μm in length/width, warty rosettes with 6–9 cylindrical rays ( Fig. 2G ). Strongylasters, with 12–15 actines, spined at the extremity, 11 (11–12) μm in diameter ( Fig. 2H ). Much larger and elongated sterrasters (186–198 x 151–160 µm) were also found on slides UPSZMC 190804 but they were considered to be contamination of another Geodia .

DNA sequence data. MT806154 (COI); OP328304 (28S); MT791489 (18S).

Figures

FIGURE 2. Geodia cf. barretti (NCPOR/HYD-CIO/0011) attached on a rock. B. thick section (cortex thickness 1 mm). Red arrow points at oxeas crossing the cortex. C. ortho/dichotriaene. D. oxeas I & II. E, F. sterraster. G. sterraster surface showing the rosettes with warts. H. strongylasters. I. oxyasters. D scale = 0.7 mm.