Myxilla (Burtonanchora) asigmata (Topsent, 1901)

Göcke, Christian & Janussen, Dorte, 2013, Demospongiae of ANT XXIV / 2 (SYSTCO I) Expedition — Antarctic Eastern Weddell Sea, Zootaxa 3692 (1), pp. 28-101 : 59

Myxilla (Burtonanchora) asigmata (Topsent, 1901)

( Fig. 10 A)

Myxilla asigmata (Topsent, 1901) : Burton 1932: 310–311. Koltun 1964: 51–52, pl. 9, figs. 8–11, 1976: 179. Myxilla (Burtonanchora) asigmata (Topsent, 1901) : Ríos & Cristobo 2007b: 529–533, figs. 5, 6, tab. 2.

Synonymy:

Lissodendoryx asigmata Topsent, 1901 :

Lissodendoryx spongiosa var. asigmata Topsent, 1901: 18 –21, 1908: 26, pl. 3, fig. 1, 1913: 625, pl. 3, fig. 3.

Material. 1 specimen from station 048-1 (SMF 11824), 602.1 m, 70° 23.94' S, 8° 19.14' W, 12.01.2008. Material examined for comparison: BMNH 1928.2.15.438, “Discovery” Investigations, Antarctic, 1925–1928, stn. 145, R.N. CIII. i., wet specimen.

Description. Observed specimen of brown color, massive with a conulose surface formed by the endings of spicule tracts protruding above the surface. Skeleton an anisotropic reticulation with thick primary tracts and less organized, uni- to paucispicular interconnecting secondary tracts. No special ectosomal skeleton, but a slight condensation of chelae in epidermis. Spicules styles, 850 x 40 µm, tylotes with slightly spiny ends, 290–350 x 10 µm, and anchorate isochelae, 70 µm long.

Remarks. The specimen is in good accordance with this well known species that has only recently been reported and documented in detail by Ríos and Cristobo (2007b). The newly found specimen described in that study was different from all previously recorded ones by the possession of chelae with five teeth on each end. This novel character so far remains unique, as we could not find chelae other than tridentates in our sponge.

Figures

FIGURE 10. Habitus pictures. A: Myxilla (Burtonanchora) asigmata (Topsent, 1901) (SMF 11824), in ethanol, B: Phelloderma sp. nov. (SMF 11726), large sponge, growing besides small T. semisuberites (SMF 11727), alive, ex situ, C: Mycale (Oxymycale) acerata Kirkpatrick, 1907 (SMF 11800), alive, ex situ, D: Axinella antarctica (Koltun, 1964) (SMF 11835), in ethanol, E: Hemigellius bidens (Topsent, 1901) (SMF 11793), in ethanol, F: Hemigellius fimbriatus (Kirkpatrick, 1907) (SMF 11810), in ethanol, G: Cladocroce gaussiana (Hentschel, 1914) (SMF 11837), in ethanol, H: Haliclona (Reniera) sp. (SMF 11818), in ethanol. Scale bars: A: 10 mm, B: 5 mm, C: 40 mm, D: 5 mm, E: 10 mm, F: 10 mm, G: 10 mm, H: 10 mm.