Manguin (1960: 329, pl. 19, figs 218, 219a, b)
[after Manguin (1960)] Cells solitary, linear, weakly sigmoidal, with rounded apices (valve view); apical axis c. 100 µm; transapical axis 3–4 µm. Fibulae 14 in 10 µm; transapical striae not visible by LM. Central nodule present.
Terre Adélie (Manguin, 1960).
This rare species was not collected by us. Manguin (1960) noted the features separating P. antarctica from the Arctic diatom Nitzschia delicatissima Cleve [= P. delicatissima< /EM > (Cleve) Heiden], the former being larger and weakly sigmoidal.