Myxilla (Burtonanchora) asigmata Topsent 1901

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.