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Navicula kotschyi

Grunow 1860      Category: Symmetrical biraphid

Navicula ingenua


Navicula lanceolata

LM scalebar = 10 µm = 80 pixels.


Contributor: Meredith Tyree | Ian Bishop - October 2015
Length Range: 18-19 µm
Width Range: 5.0-5.6 µm
Striae in 10 µm: 20-24


Valves linear with central parallel margins and distinctly capitate apices. Striae are radiate, becoming nearly parallel at the apices. The central area is bowtie-shaped, with irregularly placed shortened striae. The axial area is narrow and linear. The raphe is filiform with unilaterally deflected distal ends. Areolae are coarse and visible in LM, numbering 20-24 in 10 µm.

Note that Navicula kotschyi lacks the features of the genus Navicula sensu stricto, and is due for inclusion in another (to be described?) genus.

The species N. savannahiana and N. texana may be conspecific with N. kotschyi, as suggested by Potapova (2013). These three taxa require further comparision to determine if they are indeed distinct species.

Original Description

Author: Grunow 1860
Length Range: µm
Striae in 10 µm:

Original Description

Navicula Kotschyi nov. spec.

Navicula parvula (hine inde subserians) a latere secundario oblonga apicibus productis capitatis, nodulo centrali magno quadrangulari saepe cruciformi dilatato, striis transversalibus punctatis radiantibus, centralibus distinctioribus 36-40 in 0.001” terminalibus tenuioribus ad 50 in 0.001”. Longit. 0.0005-0.0008”, latid. 0.0002-0.00025”.

Habitat in aqua calida termarum Budensium, ubi legerunt ell. de Heufler ct Kotschy auctumno anni 1850 (inter Oscillariam maximam Kg.). Tab. nostr. II, Fig. 12 (400/1).

Aehnlich der vorigen Art, aber schmäler und noch feiner gestreift. Der Mittelknoten ist bei vielen Exemplaren mehr oder weniger erweitert, so dass ich lange genegt war, sie als Stauroneis aufzuführen. In den meisten Fällen ist der Mittelknoten jedoch quadratisch, so dass ich sie endlich zu Navicula gestellt habe, wo sie entschieden in dieser Gruppe ihre nächsten Verwandten hat. Man könnte sie für eine Jugendform der Navicula dicephala Kg. halten, wogegen jedoch ihr massenhaftes constantes Vorkommen spricht, in dem sich kein Exemplar der N. dicephala vorfand.

Original Images

Cite This Page:
Tyree, M., and Bishop, I. (2015). Navicula kotschyi. In Diatoms of the United States. Retrieved May 23, 2018, from

Species: Navicula kotschyi

Contributor: Meredith Tyree | Ian Bishop

Reviewer: Mark Edlund


Grunow, A. (1860). Uber neue oder ungenügend gekannte Algen. Verhandlungen der Kaiserlich-Königlichen Zoologisch-Botanischen Gesellschaft in Wein, 10: 503-582.

Potapova, M. (2013). The types of 22 Navicula (Bacillariophyta) species described by Ruth Patrick. Proceedings of the Academy of Natural Sciences of Philadelphia 162: 1-23.

Links & ID's

Index Nominum Algarum (INA)

Original INA

California Academy of Sciences (CAS)

Navicula kotschyi CAS

North American Diatom Ecological Database (NADED)

NADED ID: 46269

Autecology Discussion


Distribution of Navicula kotschyi in rivers of the continental U.S. based on the National Water Quality Assessment program. Retrieved 02 May 2016.

Credit/Source: USGS BioData

EMAP Assessment

The Environmental Protection Agency (EPA) western Environmental Monitoring and Assessment Program (EMAP) study was completed during the years 2000-2004 (see citations at bottom of this page). Over 1200 streams and rivers in 12 western states (Arizona, California, Colorado, Idaho, Montana, Nevada, North Dakota, Oregon, South Dakota, Utah, Washington and Wyoming) were selected for sampling based on a stratified randomized design. This type of design insures that ecological resources are sampled in proportion to their actual geographical presence. Stratified randomized design also allows for estimates of stream length with a known confidence in several “condition classes” (good or least-disturbed, intermediately-disturbed, and poor or most-disturbed) for biotic condition, chemistry and habitat.

EMAP Distribution

Navicula kotschyi

EMAP Response Plots

Navicula kotschyi

EMAP citations

Results are published in:

Johnson, T., Hermann, K., Spaulding, S., Beyea, B., Theel, C., Sada, R., Bollman, W., Bowman, J., Larsen, A., Vining, K., Ostermiller, J., Petersen, D. Hargett, E. and Zumberge, J. (2009). An ecological assessment of USEPA Region 8 streams and rivers. U.S. Environmental Protection Agency Region 8 Report, 178 p.

Stoddard, J. L., Peck, D. V., Olsen, A. R., Larsen, D. P., Van Sickle, J., Hawkins, C. P., Hughes, R. M., Whittier, T. R., Lomnicky, G. A., Herlihy, A. T., Kaufman, P. R., Peterson, S. A., Ringold, P. L., Paulsen, S. G., and Blair, R. (2005). Environmental Monitoring and Assessment Program (EMAP) western streams and rivers statistical summary. U.S. Environmental Protection Agency Report 620/R-05/006, 1,762 p.

Stoddard, J. L., Peck, D. V., Paulsen, S. G., Van Sickle, J., Hawkins, C. P., Herlihy, A. T., Hughes, R. M., Kaufman, P. R., Larsen, D. P., Lomnicky, G. A., Olsen, A. R., Peterson, S. A., Ringold, P. L., and Whittier, T. R. (2005). An ecological assessment of western streams and rivers. U.S. Environmental Protection Agency Report 620/R-05/005, 49 p.