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Authority

Manguin (1957: 123, fig. 24a–c)

Class

Diatomophyceae

Order

Pennales

Family

Cocconeidaceae

Synonyms

Cocconeis curiosa Hust. (Hustedt, 1958: 143, figs 96–99)

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Basionym

N/A

Additional References

Manguin (1960: 305, pl. 14, figs 156, 157)

Description

[after Manguin (1960)] Cells solitary, elliptical; apical axis 16–17 µm; transapical axis 11–12 µm. Transapical striae radiating, curved towards the poles, uniseriate; areolae poroid. Raphe-valve slightly concave; R-valve transapical striae 13 in 10 µm. Raphe a simple straight fissure. Pseudoraphe-valve convex; P-valve transapical striae 11 in 10 µm, the outermost areola of each stria noticeably larger.

Distribution

Cape Margérie, Terre Adélie (Manguin, 1960).

Comments

This taxon has rarely been reported and was not found by us.

Cocconeis cells are solitary and heterovalvate. One valve (the P-valve) is typically convex and bears a pseudoraphe; the other (the R-valve) is concave (or at least less convex than the P-valve) and bears a central raphe-sternum. Valve structure is usually of broad, non-areolate, transapical costae alternating with striae (intercostal areas) that contain uniseriate or multiseriate poroids (areolae). The arrangement of striae and costae on the P-valve often differs from that on the R-valve.

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