Tedania (Tedaniopsis) aurantiaca Goodwin & Brickle 2012, sp. nov.

Tedania (Tedaniopsis) aurantiaca sp. nov.

(Figure 15)

Type material: Holotype: BELUM Mc 7661. Husvik, South Georgia (54°10.285’S, 36° 40.412’W); depth 18m; collected by C. Goodwin, D. Poncet and P. Brewin, 26 th November 2010.

Paratypes: Samples in 95% ethanol, tissue section and spicule preparation on slides. BELUM Mc 7583. Prion Island Site 1, South Georgia (54°001.590’S, 37°15.178’W); depth 17.6m; collected by C. Goodwin, D. Poncet, and P. Brewin, 19 th November 2010. BELUM Mc 7624. Right Whale Bay, South Georgia (54°00.173’S, 37° 40.856’W); depth 18m; collected by C. Goodwin, J. Brown and S. Brown, 21 st November 2010. BELUM Mc 7652. Jagged Point, Possession Bay, South Georgia (54°04.514’S, 37° 07.188’W); depth 10.4m; collected by C. Goodwin, D.Poncet and P. Brewin, 23 rd November 2010. BELUM Mc 7659. Husvik, South Georgia (54°10.285’S, 36° 40.412’W); depth 18m; collected by C. Goodwin, D. Poncet and P. Brewin, 26 th November 2010. BELUM Mc 7670. Husvik, South Georgia (54°10.150’S, 36° 39.322’W); depth 18m; collected by D. Poncet, P. Brewin, C. Goodwin 26 th November 2010.

Comparative material examined: MNHN DT1667 Tedania (Tedaniopsis) charcoti Topsent, 1908 Holotype. Ile Booth-Wandel ‘ Le Francais’. Microscope preparations.

ZMB S2315 Tedania vanhöffeni var. gracilis Hentschel, 1914 (Holotype T. gracilis (Hetschel, 1914)), specimen and spicule preparation and tissue section prepared from specimen.

BMNH 79.12.27.12 Tedania tenuicapitata Ridley, 1881, Holotype. Tissue section and spicule preparation slides.

Etymology: From the Latin aurantiacus, meaning orange-coloured.

External morphology: In situ appearance: Mustard yellow to cadmium orange lobed crust with large oscules. In thicker, larger, specimens the oscules may be raised on mammiform processes (Fig. 15a).

Preserved appearance: Cream sponge composed of rounded lobes, firm, not compressible. Ectosome very smooth.

Skeleton: The choanosomal skeleton is a loose reticulation of bundles of 2–3 styles. The ectosomal skeleton consists of bundles of tornotes, which fan out to form a tangential surface layer. Onychaetes are scattered abundantly throughout the choanosome and ectosome (Fig. 15b).

Spicules: Measurements from Mc7661.

Styles: 356(407)447 by 17(21)25µm. Often slightly curved, parallel sided then tapering at the end to a sharp point (Fig. 15c).

Ectosomal tornotes: 335(359)403 by 10(13)16µm. Fusiform anisotornotes (Fig. 15d).

Onychaetes: two categories 74(90)125 and 235(261)283 by 1.7(2.1)2.8µm a few intermediates (172,206µm). The largest are pointed at both ends, the smaller with one pointed and one rounded end (Figs 15 e, f, g).

Remarks: Desqueyroux-Faúndez and van Soest (1996) reassessed the genera Tedania and Trachytedania, and reclassified the species present into three sub-genera: Tedania (Tedaniopsis) with long styles 300–700 µm, Tedania (Tedania) with short styles 150–300 µm and mucronate tornotes, and Tedania (Trachytedania) with smooth or spined short styles 150–300 µm and oxeote or mucronate tornotes (see also van Soest 2002b). The redescription of Tedania (Trachytedania) was based on the fact that no basal acanthostyles, the characterizing feature of the genus, could be found in the type species. Trachytedania has since been re-established as a valid genus by Cristobo and Urgorri (2001) who re-examined the type and located basal acanthostyles. This species confirms to the current definition of Tedania (Tedaniopsis) as it possesses styles longer than 350µm (Desqueyroux-Faúndez and van Soest 1996).

There are many Southern Ocean species within this subgenus but the majority have spicules that are much larger (Table 8). Three species have spicules of a similar range: T. gracilis (Hentschel, 1914) is the most similar in spicule size but has larger styles and shorter tornotes (Table 8). Comparison with the specimen designated as the holotype showed this has much thinner, longer styles (552(591)653 by 12(15)16µm) and thinner ectosomal spicules (397(437)490 by 6(9)13µm), however, this specimen may not be the one described in type description as it appears to differ in spiculation and is a thinly encrusting species on a bryozoan rather a sea urchin. T. charcoti Topsent, 1908 has much thinner styles (420–450 by 13µm in description, 401(434)466 by 9(13)16 µm from our measurements of type) and smaller tornotes (305–340 by10µm from description, 280–350 by 8(10)14µm from our measurements). Tedania tenuicapitata Ridley, 1881 has much smaller styles (296–387µm), tornotes (185–270µm), and onychaetes (132–327, 52–75µm) (Table 8).