Myxilla Schmidt, 1862

Morozov, Grigori, Sabirov, Rushan Mirzovich & Anisimova, Natalia, 2018, New data on sponges from Svalbard Archipelago with a description of a new species of Halicnemia, Journal of Natural History (J. Nat. Hist.) 52 (7 - 8), pp. 491-507 : 497-498

Subgenus Myxilla Schmidt, 1862

Myxilla (Myxilla) perspinosa Lundbeck, 1905

( Figure 4 (a–e))

Myxilla perspinosa Lundbeck 1905, p. 147 , pl. V, fig. 1, pl. XIV, fig. 7a–e; Hentschel 1929, p. 944

Myxilla incrustans var. perspinosa: Koltun 1959, pp. 109–110 , fig. 62

Description

( Figure 4 (a)) The form is irregularly cloddy, massive-lobose, about 3.5 cm in height and 4 cm in length. Surface uneven, slightly scabrous and coarse-pored, covered with a thin dermal membrane. The consistency of sponge is compressible, but not strong in tension. Colour light brown.

Skeleton

( Figure 4 (b)) The main skeleton consists of a quite loose or diffuse network of bundles of spicules and single spicules; rather long and thick spicule-bundles occur. Skeleton of dermal membrane is formed by spicules lying tangentially.

Spicules

( Figure 4 (c–e)) Acanthostyles, dimensions: 178.9–262.5–305 (n = 30) × 6.1–8.1– 9.5 µm (n = 15); lanceolately pointed tornotes, with a slightly spined ends (not common), dimensions: 178.2–215.3–255.8 (n = 30) × 3.6–5.87– 7 µm (n = 15); three-toothed chelae, sometimes with additional narrow ‘alae’ on the shaft, dimensions: 13–23.98– 59.3 µm (n = 25); sigmas, both c- and s-shaped, dimensions: 20.6–34.53– 63.2 µm (n = 35).

Distribution

Norwegian ( Jan Mayen Island), Iceland, Barents and White Seas, west of Spitsbergen, Spitsbergen Bank, Bering (Avacha Bay) and Okhotsk Seas, Sea of Japan, near the Shikotan Island.

Figures

Figure 4. M. perspinosa, (a) habitus; (b) cross section through the inner part of the sponge; (c–f) SEM images of spicules; (c) acanthostyle; (d) tornote; (e) sigma, (e) chelae.