Taxon Account

Cocconeis euglypta Ehrenberg; 1854; 8

Synonymy

Cocconeis lineata var. euglypta (Ehrenberg) Grunow in Van Heurck 1880
Cocconeis placentula var. euglypta (Ehrenberg) Grunow 1884

Key references

Monnier O., Rimet F., Bey M., Chavaux R., Ector L. 2007. Sur l’identité de Cocconeis euglypta Ehrenberg 1854 et C. lineata Ehrenberg 1843 – Une approche par les sources historiques. Diatomania. 11: 30-45.

Shape
Elliptic with obtuse point particularly on raphe valve; raphe valve concave, rapheless valve convex, flexed in girdle view.

Symmetry
Valves isopolar, bilaterally symmetrical.

Valve
Frustules heterovalvar, one valve with raphe, one valve without raphe.

Striae
On raphe valve striae comprising dot-like areolae, slightly radiate to radiate, interrupted towards margin by raised siliceous rim; on rapheless valve striae slightly radiate to radiate, comprising transapically elongate areolae, forming slightly irregular, curving, more or less parallel longitudinal lines.

Axial area
On raphe valve narrow linear, straight, terminating at marginal ridge; on rapheless valve barely visible, narrow pore-free area.

Central area
On raphe valve hardly wider than axial area; absent on rapheless valve.

Raphe
Straight with expanded proximal ends, positioned close together; terminal ends straight, ending at ridge.
This page should be cited as:

Cox E. J., Jones V., Jüttner I. Cocconeis euglypta Ehrenberg; 1854; 8. In: Jüttner I., Carter C., Cox E.J., Ector L., Jones V., Kelly M.G., Kennedy B., Mann D.G., Turner J. A., Van de Vijver B., Wetzel C.E., Williams D.M. 2025 . Freshwater Diatom Flora of Britain and Ireland. Amgueddfa Cymru - National Museum Wales. Available online at https://naturalhistory.museumwales.ac.uk/diatoms/browsespecies.php?-recid=4352. [Accessed:  4 April 2025].

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Record last modified: 27/12/2020