van Heurck (1909: 8, pl. 1, fig. 3)
Amphora racovitzae var. minor Perag. (Peragallo, 1921: 61)
Manguin (1960: 327, pl. 18, fig. 210)
Cells solitary, elliptical, with truncate ends in girdle view; apical axis 31–100 µm; transapical axis 8.4–15 µm. Valves asymmetrical about the apical plane; dorsal side arcuate; ventral side concave, orientated such that the raphes lie in the same side of the cell. Raphes eccentric, biarcuate; internal endings simple. Striae uniseriate, coarse; dorsal striae 7 in 10 µm; ventral striae 6–7 in 10 µm. Areolae slit-like. Girdle bands numerous, plain (Fig. c).
Burton Lake, sea-ice and coastal waters of Plough I., Kazak I., near Davis Station, East Antarctica; type locality, 64°25'S 62°02'W, Drake Passage (van Heurck, 1909); Petermann I., Antarctic Peninsula (Peragallo, 1921); Cape Margérie, Terre Adélie (Manguin, 1960).
Cells found in Burton Lake sea-ice and coastal waters near Davis Station were small, with the apical axis 31–53 µm, the transapical axis 8.4–10 µm, width in girdle view 20–29 µm and striae 10–11 in 10 µm. They were very much in the size range of the Amphora racovitzae var. minor material reported by Peragallo (1921).
Most species of Amphora described from Antarctic waters have been based on early collections. Examination of material (especially by electron microscopy) is required in order to clarify many taxa, while Round et al. (1990) pointed out that the genus itself requires revision. In the present study, only A. racovitzae was identified with certainty. Three other species were also found (types A, B, C), but they remain unidentified.
Van Heurck (1909) listed the following species collected on the “Belgica ” Expedition: A. racovitzae van Heurck, A. angusta var. angustissima van Heurck, A. arcta A.W.F.Schmidt, A. cymbelloides Grunow, A. mexicana var. schmidtiana van Heurck, A. peragallorum van Heurck, A. peragallorum var. robusta van Heurck and A. proteus var. oculata Perag. Hustedt (1958) described A. antarctica (similar to A. cymbelloides) from 69°43’S 06°30’E, off Dronning Maud Land.
Peragallo (1921) listed the following species collected during Charcot’s “Porquoi Pas?” Expedition of 1908–10: A. bongrainii Perag., A. gourdonii Perag., A. charcotii Perag., A. petermannii Perag., A. proteus W.Greg., A. racovitzae van Heurck, A. racovitzae var. minor van Heurck, A. senonquei Perag., A. virgata Østrup, A. virgata var. crassa Perag., A. peragallorum van Heurck, A. turgida W.Greg., A. lanceolata Cleve, A. lanceolata var. aperta Perag., A. lanceolata var. robusta Perag. and A. liouvellei Perag.