Nupela impexiformis

(Lange-Bertalot in Lange-Bertalot and Krammer) Lange-Bertalot 1999      Category: Symmetrical biraphid
BASIONYM: Achnanthes impexiformis Lange-Bertalot in Lange-Bertalot and Krammer 1989

Nupela frezelii


Nupela lapidosa

LM scalebar = 10 µm = 80 pixels.


Contributor: Marina Potapova - March 2011
Length Range: 14-17 µm
Width Range: 3.8-4.6 µm
Striae in 10 µm: 44-50


Valves are elliptical-lanceolate with capitate ends. Striae are radiate, rarely discernible in LM. Axial area is linear-lanceolate. Central area is large, asymmetrical, reaching valve margin on one side of the valve. The raphe is absent on one of the valves. The raphe is straight. External proximal raphe ends are simple or slightly expanded.

Original Description

Basionym: Achnanthes impexiformis
Author: Lange-Bertalot in Lange-Bertalot and Krammer 1989
Length Range: 12-16 µm
Width Range: 3.5-4.5 µm
Striae in 10 µm: 45-55

Original Description

Original Images

Cite This Page:
Potapova, M. (2011). Nupela impexiformis . In Diatoms of the United States. Retrieved November 29, 2015, from

Species: Nupela impexiformis

Contributor: Marina Potapova

Reviewer: Sam Rushforth, Sarah Spaulding


Lange-Bertalot, H. (1999). Neue Kombinationen von taxa aus Achnanthes Bory (sensu lato). Iconographia Diatomologica 6: 276-289.

Lange-Bertalot, H. and Krammer, K. (1989). Achnanthes eine Monographie der Gattung mit Definition der Gattung Cocconeis and Nachtragen zu den Naviculaceae. Bibliotheca Diatomologica 18, 393 pp. Cramer, Berlin, Stuttgart.

Links & ID's

Index Nominum Algarum (INA)

California Academy of Sciences (CAS)

Nupela impexiformis CAS

North American Diatom Ecological Database (NADED)

NADED ID: 92015

Autecology Discussion