Encyonema reichardtii

(Krammer) D.G.Mann 1990      Category: Asymmetrical biraphid
BASIONYM: Cymbella reichardtii Krammer 1985

Encyonema pergracile


Encyonema reimeri

LM scalebar = 10 µm = 80 pixels.


Contributor: Ian Bishop - December 2017
Length Range: 10-17 µm
Width Range: 3.3-4.3 µm
Striae in 10 µm: 14-20 on dorsal; 16-20 on ventral side


Valves are small and moderately dorsiventral, with slightly protracted, rounded ends. The dorsal margin is semi-elliptic. The ventral margin varies, ranging from slightly concave to flat to clearly convex. The raphe is straight and filiform and has inflated, dorsally deflected proximal ends. The distal raphe ends are strongly recurved to the ventral margin. Central striae are somewhat irregular, curved and radiate and lower in density, characteristically with a gap between the ventral central striae. Throughout the rest of the valve, striae transition from weakly radiate to parallel to convergent at the apices.

Original Description

Basionym: Cymbella reichardtii
Author: Krammer 1985
Length Range: 8-12.5 µm
Width Range: 3-4 µm
Striae in 10 µm: 18-22

Original Description

Original Images

Cite This Page:
Bishop, I. (2017). Encyonema reichardtii. In Diatoms of the United States. Retrieved April 23, 2018, from http://westerndiatoms.colorado.edu/taxa/species/encyonema_reichardtii

Species: Encyonema reichardtii

Contributor: Ian Bishop

Reviewer: Rosalina Stancheva


Cremer, H., Wagner, B., Melles, M. and Hubberten, H. (2001). The postglacial environmental development of Raffles Sø, East Greenland: inferences from a 10,000 year diatom record. Journal of Paleolimnology 26: 67-87. 10.1023/A:1011179321529

Ivanov, P., Kirilova, E., and Ector, L. (2006). Diatom species composition from the River Iskar in the Sofia region, Bulgaria. In Advances in phycological studies Festschrift in honour of Prof. Dobrina Temniskova-Topalova, 167-190.

Krammer, K. and Lange-Bertalot, H. (1985). Naviculaceae Neue und wenig bekannte Taxa, neue Kombinationen und Synonyme sowie Bemerkungen zu einigen Gattungen. Bibliotheca Diatomologica 9:5-230, 43 pls.

Noga, T., Kochman, N., Peszek, Ł., Stanek-Tarkowska, J., and Pajączek, A. (2014). Diatoms (Bacillariophyceae) in rivers and streams and on cultivated soils of the Podkarpacie region in the years 2007-2011. Journal of Ecological Engineering 15(1): 6-25. 10.12911/22998993.1084168

Potapova, M. (2014). Diatoms of Bering Island, Kamchatka, Russia. Nova Hedwigia 143: 63-102.

Round, F.E., Crawford, R.M. and Mann, D.G. (1990). The Diatoms. Biology and Morphology of the Genera. Cambridge University Press, Cambridge, 747 pp.

Links & ID's

Index Nominum Algarum (INA)

Transfer INA
Original INA

California Academy of Sciences (CAS)

Encyonema reichardtii CAS

North American Diatom Ecological Database (NADED)

NADED ID: 110014

Autecology Discussion

Encyonema reichardtii has a cosmopolitan distributions among holoarctic rivers and streams. It has been recorded, sometimes in great abundance, in places as varied as East Greenland (Cremer et al. 2001), Luxembourg (Rimet et al. 2004), Bulgaria (Ivanov et al. 2006), the Carpathian Mountains (Noga et al. 2014), Bering Island (Potapova 2014), and in streams throughout the United States (see Google Earth Map below), reaching the greatest abundances in rivers of eastern states.


Distribution of Encyonema reichardtii in rivers of the continental U.S. based on the National Water Quality Assessment program. Retrieved 028 June 2017.

Credit/Source: USGS BioData