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Eunotia zasuminensis

(Cabejsz.) Körner 1970      Category: Eunotioid
BASIONYM: Fragilaria zasuminensis Cabejsz. 1937
SYNONYM(S): Asterionella zasuminensis (Cabejsz.) Lundh-Alm. 

Eunotia triodon


Eupodiscus radiatus

LM scalebar = 10 µm = 80 pixels.


Contributor: David R.L. Burge | Mark Edlund - June 2017
Length Range: 38-60 µm
Width Range: 1.7-2.5 µm
Striae in 10 µm: 20-22


Valves linear and elongate, weakly dorsiventral. The dorsal margin is slightly convex and the ventral margin is slightly concave giving the valves slight asymmetry appearance to the apical axis. Valves can sometimes be irregularly wavy. Apices capitate, 3.5-4.0 µm wide, ending truncate. Raphe short, present on the ventral face-mantle junction on the ventral side of each valve end. The transapical striae are parallel throughout. In girdle view the valves are often not straight and the apices are expanded in the pervalvar axis.

Original Description

Basionym: Fragilaria zasuminensis
Author: Cabejsz. 1937
Length Range: µm
Striae in 10 µm:

Original Description

Original Images

Cite This Page:
Burge, D., and Edlund, M. (2017). Eunotia zasuminensis. In Diatoms of the United States. Retrieved May 25, 2018, from

Species: Eunotia zasuminensis

Contributor: David R.L. Burge | Mark Edlund

Reviewer: Eduardo A. Morales


Cabejszekówna, I. (1937). Fragilaria zasuminensis n. sp. w jeziorze Zasumiñskim na Polesiu. Arch. Hydrobiol. Rybactwa 10: 423–425.

Eloranta, P. (1986). Melosira distans var. tenella and Eunotia zasuminensis, two poorly known planktonic diatoms in Finnish lakes. Nordic Journal of Botany 6(1): 99-103.

Körner, H. (1970). Morphologie und Taxonomie der Diatomeen Gattung Asterionella. Nova Hedwigia 20: 557-724.

Siver, P.A., Hamilton, P.B. and Morales, E.A. (2006). Two new planktic species of Eunotia (Bacillariophyceae) from freshwater waterbodies in North Carolina, USA. Algological Studies 119(1): 1-16.

Wetzel, C.E., Ector, L., Hoffmann, L. and Bicudo, D.C. (2010). Colonial planktonic Eunotia (Bacillariophyceae) from Brazilian Amazon: Taxonomy and biogeographical considerations on the E. asterionelloides species complex . Nova Hedwigia 91: 49-86. 10.1127/0029-5035/2010/0091-0049

Links & ID's

Index Nominum Algarum (INA)

Transfer INA
Original INA

California Academy of Sciences (CAS)

Eunotia zasuminensis CAS

North American Diatom Ecological Database (NADED)

NADED ID: 33067

Autecology Discussion

Eunotia zasuminensis is reported from low alkalinity and dystrophic lakes of the Adirondacks. In lakes of Finland, E. zasuminensis forms zig-zag to stellate colonies and was most abundant in the summer months of July and August (Eloranta 1986). In addition to being reported in lakes, this taxon has also been reported from large rivers in the Amazon River Basin (Wetzel et al. 2010). Material illustrated here is from boreal lakes in northern Minnesota (Voyageurs National Park) and was collected as part of the National Park Service Great Lakes Inventory and Monitoring Network.


The distribution of Eunotia zasuminensis in rivers of the United States. Accessed on July 5, 2017

Credit/Source: USGS Biodata