Authority
(Grunow) Ostenf. (Ostenfeld, 1903: 6)
Class
Diatomophyceae
Order
Centrales
Family
Corethraceae
Synonyms
Corethron hispidum Castrac. (Castracane, 1886: 86, pl. 20, figs 3, 5)Corethron criophilum Castrac. (Castracane, 1886: 85, pl. 21, fig.14)Corethron murrayanum Castrac. (Castracane, 1886: 86, pl. 21, fig. 4)Corethron pelagicum Brun (1891: 20, pl. 19, fig. 6)Corethron valdiviae G.Karst. (Karsten, 1904: 544, tab. 23; 1905: 101, pl. 12, figs 1–10)
Basionym
Actiniscus pennatus Grunow, in van Heurck (1883: pl. 82bis, figs 11, 12)
Additional References
Hendey (1937: 325–329, pl. vii, viii), Manguin (1954: 16), Hustedt (1958: 130), Hasle (1969: 77, 79, figs 23, 42), Fryxell & Hasle (1971: 335, figs 1–6), Priddle & Fryxell (1985: 54, figs A, C–I), Thomas & Bonham (1990: 105, pl. 12, figs 1, 3, 5), Moisan & Fryxell (1993: 493), Hasle & Syvertsen (1997: 96, pl. 15), Crawford et al. (1998: 5, figs 1, 6–25)
Description
Cells usually solitary, strongly silicified, cylindrical, heterovalvate; pervalvar axis 20–240 µm. Valves convex, circular; apical axis 5–82 µm. Upper valve with 2 types of spines around the margin (one long and barbed, the other short and hooked); hook with 2 distinctprojections at right angles to spine (Fig. e). Lower valve with a marginal ring of barbed spines (Fig. c); spines T-shaped at their base, inserted into sockets on valve margin. Prior to cell division, spines held within the parent cingulum (girdle) all point in the same direction; cells free of the cingulum have barbed spines orientated downwards and hooked spines orientated upwards. Spines entirely absent in some specimens. Terminal corona of hairs sometimes present (Fig. c). Cingulum composed of alternating open ligulate bands (Fig. f). Auxospores illustrated by Karsten (1904, tab. 23, as C. valdiviae).
Distribution
Antarctic inshore waters (Fryxell & Hasle, 1971); near Davis Station, East Antarctica (Archer et al., 1996); Heard I. (Manguin, 1954); Ross Sea (Hendey, 1937; Andreoli et al., 1995); KERFIX, 50°40’S 68°25’E, Southern Ocean (Kopczyńska et al., 1998); Southern Ocean, south of the Antarctic Polar Front, cosmopolitan through tropical waters to the Arctic (Thomas & Bonham, 1990); Weddell-Scotia Sea (Garrison et al., 1987).
Comments
N/A