Haliclona (Gellius) cf. flabelliformes (Ridley & Dendy, 1886)

Göcke, Christian & Janussen, Dorte, 2013, Demospongiae of ANT XXIV / 2 (SYSTCO I) Expedition — Antarctic Eastern Weddell Sea, Zootaxa 3692 (1), pp. 28-101 : 81

Haliclona (Gellius) cf. flabelliformes (Ridley & Dendy, 1886)

( Fig. 19 , Tab. 15 )

Haliclona (Gellius) flabelliformes (Ridley & Dendy, 1886) : following reassignment of Gellius Gray, 1867 as subgenus to Haliclona Grant, 1836 in de Weerdt 2000: 9.

Synonymy:

Gellius flabelliformis Ridley & Dendy, 1886: 334, 1887: 45 –46, pl. 26, figs. 5, 5a. Hentschel 1914: 131, pl. 8, fig. 12. Boury- Esnault & van Beveren 1982: 113–115, fig 34f–h.

Material. 1 specimen from station 048-1 (SMF 11858), 602.1 m, 70° 23.94' S, 8° 19.14' W, 12.01.2008. Material examined for comparison: BMNH 1887.5.2.153, holotype, Challenger colln., stn. 320, wet specimen.

Description. Specimen from stn. 048-1 a fragment ( Fig. 19 A), 40 x 30 x 10 mm in size. On one side, probably the upper side, two small specimens of T. leptoderma growing, 5 and 8 mm in diameter. Shape of living sponge unknown. Colour in ethanol greyish-beige.

Skeleton: Skeleton ( Fig. 19 B) of preserved specimen in poor state; a very poor organization visible with oxeas somewhat longitudinally arranged, partly forming weak tracts with single interconnecting spicules. Microscleres distributed throughout the tissue in a disorganised manner.

Spiculation ( Tab. 15 ): Main spicules very large almost straight oxeas with relatively blunt ends ( Fig. 19 C), about 1097 x 25 µm. Most common microscleres toxas ( Fig. 19 E–F), 135 x 4 µm. These very characteristic in shape, sharp, almost rectangularly bent in the middle, with short thin end pieces often slightly bent upwards. In center, sometimes small tyles present. Also present are small c-shaped sigmas ( Fig. 19 D), about 24 µm in length and 14 µm in width.

Remarks. An exact identification of the sponge is almost impossible, due to the bad state of preservation. The known species which bears the closest resemblance to our specimen is H. (G.) flabelliformes . The species was reported by Ridley and Dendy (1887) to show flabellate, thin, upright growth form, which is in contrast to our flat specimen. Ridley and Dendy (1887) also reported an irregular skeleton forming some sort of weak reticulation. This is well in accordance with the definition of the subgenus Haliclona (Gellius) as it is given in de Weerdt (2002). The spicule sizes reported by Ridley and Dendy (1887; compare Tab. 15 ) are quite similar to those obtained here. Still, differences are present especially in length of oxeas and sigmas. Oxeas are much larger in our SYSTCOsponge, while sigmas are considerably smaller. The characteristic toxas, which are only described, but not figured by Ridley and Dendy (1887), seem to be quite similar, although a bit smaller in our specimen. Those toxas are quite rare among Haliclona (Gellius) spp., especially in combination with such large oxeas. Therefore it seems not completely certain that our specimen really belongs to the species H. (G.) flabelliformes , but this is the species with the most shared similarities. The question of a more exact identification, or even a possible description as a new species, cannot be answered due to the bad state of preservation of the specimen.

Figures

FIGURE 19. Haliclona (Gellius) cf. flabelliformis (Ridley & Dendy, 1886), SMF 11858. A, habit in ethanol, on the surface of the sponge grow two small specimens of Tetilla leptoderma (SMF 11763). B, skeletal section. C, oxea. D, sigma. E – F, toxas. Scale bars: A: 10 mm, B: 1 mm, C: 100 µm, D: 5 µm, E – F: 30 µm.