Haliclona (Reniera) oberi, Sim-Smith & Hickman & Kelly, 2021

Sim-Smith, Carina, Hickman, Cleveland & Kelly, Michelle, 2021, New shallow-water sponges (Porifera) from the Galápagos Islands, Zootaxa 5012 (1), pp. 1-71 : 19-20

Haliclona (Reniera) oberi sp. nov.

( Fig. 8 , Table 2)

Material examined. Holotype — MCCDRS9440, Nameless Island , 0.67° S, 90.586° W, 18 m, 9 Aug 2003.

Type locality. Nameless Island .

Habitat and distribution. Only known from type locality. Found growing in a small recess on a vertical rock wall; 18 m.

Description. Thinly encrusting sponge, 3 mm thick, with several oscules (3 mm in diameter) that have slightly raised, translucent margins. The terminal ends of dense aquiferous canals are visible under the semi-translucent surface giving the sponge a punctate appearance. Colour in life is light pinkish apricot, colour in ethanol is tan ( Fig. 8A–B ). Texture is extremely soft, delicate and easily torn.

Skeleton. The ectosome and the choanosome are both unispicular, isotropic reticulations, with the ectosome a single tangential layer ( Fig. 8C–D ). Some paucispicular tracts are present in some sections of the choanosome. Spongin is moderately abundant at the spicule nodes.

Spicules. Megascleres —Oxeas, small, relatively stout with pointed tips; 135 (118–154) × 9 (7–12) µm (n = 20) ( Fig. 8E ). Numerous smaller, thinner oxeas are also present, but these are likely to be immature spicules.

Etymology. Named after William Ober MD, companion for numerous dives while assisting in the photography and collection of these sponges. He also contributed with his fine illustrations to the publication of the Galápagos Marine Life Series of field guides.

Remarks. Only one species of Haliclona (Reniera) have been described from the tropical/subtropical eastern Pacific ( Table 2). Haliclona (R.) caduca Hajdu, Desqueyroux-Faúndez, Carvalho, Lôbo-Hajdu & Willenz, 2013 from Chile is a lobed sponge that has smaller oxeas (101 (85–113) µm) than H. (R.) oberi sp. nov. The six species of Haliclona (subgenus unknown) from the eastern Pacific, as described for H. (H.) clairae sp. nov. above, all differ from this species, as outlined in Table 2.

Subgenus Soestella De Weerdt, 2000

Diagnosis. Chalinidae with a subanisotropic choanosomal skeleton consisting of ill-defined paucispicular primary lines, irregularly connected by paucispicular secondary lines. There is a slight but consistent tendency of the spicules to form rounded meshes. Ectosomal skeleton a discontinuous, tangential, rather open reticulation, due to many rounded meshes framed by spicules in lines of 2–5 spicules thick. Spongin always present at the nodes of spicules, but never abundant. Oxeas usually slender. Microscleres, if present, sigmas, toxas or raphides (from De Weerdt 2002).

Figures

FIGURE 8. Haliclona (Reniera) oberi sp. nov. holotype MCCDRS9440: A. In situ. B. Preserved specimen. C. Surface view of sponge showing the tangential ectosome. D. Cross section of the choanosome. E. Oxeas.