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Eucocconeis alpestris

(Brun) Lange-Bert. in Lange-Bert. and Genkal 1999      Category: Monoraphid
BASIONYM: Achnanthes flexella var. alpestris Brun 1880
SYNONYM(S): Achnanthes flexella var. alpestris Brun | Achnanthes alpestris (Brun) Lange-Bert. and Metzeltin | Eucocconeis flexella var. alpestris (Brun) Hust. 

Epithemia turgida


Eucocconeis americana

LM scalebar = 10 µm = 80 pixels.


Contributor: Marina Potapova - October 2010
Length Range: 12-22 µm
Width Range: 5.9-7.6 µm
Striae in 10 µm: 25-30


Valves are rectangular-elliptical with slanted ends or in the shape of a parallelogram, often twisted. The raphe valve has an oblique narrow linear or slightly sigmoid axial area and a transversely rectangular central area. The raphe is slightly sigmoid with terminal raphe fissures curved to opposite directions. The rapheless valve has a narrow linear or slightly sigmoid axial area, which is also often oblique. The central area on rapheless valve is large, hexagonal to diamond-shaped or rounded. The striae are punctate, slightly radiate, or radiate on one side of the valve, but parallel to slightly convergent on the other side, 25-30 in 10 μm.

Original Description

Basionym: Achnanthes flexella var. alpestris
Author: Brun 1880
Length Range: 15-45 µm
Striae in 10 µm:

Original Description

Var. : Alpestris. Nova, Pl. III, fig. 26. — L. 15 à 45 μ. — F.v. courbée, ventrue, à terminaisons larges, arrondies et un peu capitulées ; stries subtiles; nœud large, ordinairement conique. F.v. à simple courbure. Sources des Alpes et de la région montagneuse; assez commune.

Original Images

Cite This Page:
Potapova, M. (2010). Eucocconeis alpestris. In Diatoms of the United States. Retrieved May 22, 2018, from

Species: Eucocconeis alpestris

Contributor: Marina Potapova

Reviewer: Mark Edlund


Brun, J. (1880). Diatomées des Alpes et du Jura et de la région Suisse et Française des Environs de Genève. Imprimerie Ch. Schuchardt, Genève. 146 pp.

Lange-Bertalot, H. and Genkal, S.I. (1999). Diatoms from Siberia I. Islands in the Arctic Ocean (Yugorsky-Shar Strait). Iconographia Diatomologica 6: 1-292.

Links & ID's

Index Nominum Algarum (INA)

Original INA

California Academy of Sciences (CAS)

North American Diatom Ecological Database (NADED)

NADED ID: 187005

Autecology Discussion