Taxon Account

Navicula gregaria Donkin; 1861; 10

Synonymy

Navicula gregalis Cholnoky 1963

Key references

Cox E.J. 1995. Studies on the diatom genus Navicula Bory. VII. The identity and typification of Navicula gregaria Donkin, N. cryptocephala and related taxa. Diatom Research. 10(1): 91-111.

Morphology

Size
13-42 µm long, 5-10 µm wide.

Shape
Broadly lanceolate with rostrate apices.

Symmetry
Isopolar, bilaterally symmetrical.

Striae
Parallel, very slightly radiate at centre, convergent for last third of valve to apices; 18-22 in 10 µm (UK population).

Axial area
Narrow linear.

Central area
Often slightly asymmetric, more rounded on one side, squarish on other; occupying up to half of the valve width.

Raphe
Straight, central endings slightly expanded and deflected to primary side; terminal endings hooked close to the apices.

Other features
Central nodule slightly thicker than raphe sternum and slightly expanded to primary side.

Literature

References are given in chronological order.

Reference
Citation
Donkin A.S. 1861. On the marine Diatomaceae of Northumberland, with a description of several new species. Quarterly Journal of Microscopical Science, new series, London. 1: 1-15; 1 pl. Morphology; Taxonomy; Description; Illustrations; Ecology
Schoenman F.R., Archibald R.E.M. 1976. The Diatom Flora of Southern Africa. National Institute for Water Research, Council for Scientific and Industrial Research, WAT 50. Morphology; Type Illustration; Ecology
Cox E.J. 1995. Studies on the diatom genus Navicula Bory. VII. The identity and typification of Navicula gregaria Donkin, N. cryptocephala and related taxa. Diatom Research. 10(1): 91-111. Morphology; Taxonomy; Type Illustration
Cox E.J. 1995. Morphological variation in widely distributed diatom taxa: taxonomic and ecological implications. In: Marino D., Montreso M. Proceedings of the 13th International Diatom Symposium, Maratea, Biopress, Bristol. 335-345 pp Morphology; Illustrations; Ecology
Hofmann G., Werum M., Lange-Bertalot H. 2011. Diatomeen im Süßwasser-Benthos von Mitteleuropa. A.R.G. Gantner, Ruggell. 908 pp Morphology; Ecology; Illustrations

Similar Species

Similar species not published on this website:

Navicula supergregaria Lange-Bertalot & Rumrich; 2000; 171

This page should be cited as:

Cox E. J. Navicula gregaria Donkin; 1861; 10. In: Jüttner I., Bennion H., Carter C., Cox E.J., Ector L., Flower R., Jones V., Kelly M.G., Mann D.G., Sayer C., Turner J. A., Williams D.M.. Freshwater Diatom Flora of Britain and Ireland. Amgueddfa Cymru - National Museum Wales. Available online at https://naturalhistory.museumwales.ac.uk/diatoms/browsespecies.php?-recid=2578. [Accessed:  ].

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Record last modified: 27/12/2020