Hasle, Syvertsen & Medlin (1994: 252, figs 27–30, 51–55, 57–60, 68–75, 142c)
[after Hasle et al. (1994)] Cells united at poles to form stellate or bundle-shaped colonies. Valves linear to lanceolate, with rostrate or subcapitate ends; apical axis 17–48 µm; transapical axis 3.5–5 µm. In girdle view, cells narrowly linear with deep valve mantles. Transapical striae parallel, 11–14 in 10 µm, uniseriate; areolae poroid. Sternum broad. Each valve end with an apical field of 5–8 longitudinal slits through the valve wall. Labiate process solitary, close to one valve end.
Coastal waters off Casey Station, East Antarctica; type locality, Antarctic sea-ice, 75°35’S 26°46’W [IMBB Sample 2486] (Hasle et al., 1994); South Atlantic, Weddell Sea, Terre Adélie, McMurdo Sound (see Hasle et al., 1994).
Hasle et al. (1994) included Fragilaria (?) “sp. a” Tanimura (in Tanimura et al., 1990: 28, figs 4, 5, 7) as a synonym of S. recta.
Some species formerly included in Fragilaria and Synedra have been transferred to Synedropsis on the basis of their valve striation, the occurrence and structure of labiate processes and apical pore (slit) fields and the nature of the girdle (Hasle et al., 1994). Synedropsis hyperboreoides and S. laevis were collected in the present study, and several other species, e.g. S. fragilis, S. recta, S. lata var. lata and S. lata var. angustata, have been described from Antarctic locations (Hasle, 1994).