Sponge fauna of the New Siberian Shoal: biodiversity and some features of formation Author Morozov, Grigori Author Sabirov, Rushan Author Zimina, Olga text Journal of Natural History 2019 2019-01-08 52 47 2961 2992 journal article 24132 10.1080/00222933.2018.1554166 bd9add32-702b-495c-9ed7-7ed98fb4c591 1464-5262 3654165 FA2EDE40-93E0-43B7-9ACF-ECCE12B0E671 Suberites montalbidus Carter, 1880 ( Figure 8 (a – h)) suberites montalbidus Carter 1880 , p. 256 ; Fristedt 1887 , p. 428 – 429 ; Swartschewsky 1906, p. 318 – 319, pl. XIII, fig. 3 suberites sp.: Vosmaer 1882 , p. 32 – 33; pl. I, figs 22 – 23; pl. IV, figs 140 – 144 suberites montalbidus : Lambe 1895 (?), p. 127 – 128; pl. III, fig. 6a – c suberites domuncula fi cus : Koltun 1959 (?), p. 95, figs 66 – 67; pl. XXXIV, figs 1 – 3; pl. XXXVI, figs 1 – 2 Figure 8. suberites montalbidus : (a, b) longitudinal sections through the surface (a) and inner part (b) of the sponge; (c, d) habitus; (e–h) scanning electron microscope (SEM) images of spicules; (e) large tylostyle; (f) small tylostyle; (g, h) microxea and microstrongyles, respectively. Description ( Figure 8 (c – d)). Sponge elongated, pear shaped or conical, sometimes laterally flattened, up to 5.5 cm in height and 4.5 cm in width. Body slightly narrows downwards forming a short peduncle, by which the sponge attaches on stones or on polychaetes tubes. The surface is rugose, sometimes nearly smooth (only juvenile forms). The consistency is soft and elastic. The single osculum of roundish or slit-like form (about 2 mm in diameter) is placed at the summit and surrounded by the short (about 0.8 mm in height) spicular collar (not always). Colour (in alcohol) ash grey or pale pink. Six specimens examined. Skeleton ( Figure 8 (a – b)). The main skeleton consists of a quite loose or diffuse network of spicule bundles and single spicules. Only near the surface, spicules (mostly small tylostyles) become more or less regularly arranged, and grouped in the radial bundles. The cortex is composed of a thin layer of microscleres. In the underlying tissues (choanosome) microscleres are absent. Only in rare exceptions were they found in the walls of the aquiferous system. Spicules ( Figure 8 (e – h)). Styles (tylo- and subtylostyles) straight, rather short-pointed (spicules with blunt apical ends occasionally found), dimensions: 167.7 – 387.8 – 538.9 × 5.4 – 11 ( n = 200) µm; microxea and microstrongyles centrotylote, spined, dimensions 16.7 – 38.29 – 62.9 ( n = 60) µm and 8.2 – 19.57 – 36 ( n = 60) µm, respectively. Distribution Bering Sea, West and East Greenland Shelf. Chukchi Sea, East Siberian Sea , Laptev Sea, Kara Sea, Barents Sea, White Sea, North Sea . Depth range: 5 – 113 m . Remarks Widespread circumpolar boreal-Arctic species. Quite polymorphic, and is represented by at least two morphologically close species. It is possible that some specimens of suberites montalbidus examined by Fristedt (1887) , Lambe (1895) and Koltun (1959) are actually represented by a similar, newly allocated species, suberites cebriones sp. nov.