Taxon Account

Nitzschia inconspicua Grunow; 1862; 579


Nitzschia frustulum var. inconspicua (Grunow) Grunow sensa auct. nonnull.

Key references

Trobajo R., Rovira L., Ector L., Wetzel C.E., Kelly M., Mann D.G. 2013. Morphology and identity of some ecologically important small Nitzschia species. Diatom Research. 28(1): 37-59.


4-25 µm long, 2.3-3.2 µm wide (Mann et al. 2013, Trobajo et al. 2013).

Valves linear-lanceolate to elliptic-lanceolate with slightly protracted, narrow apices.

Isopolar, bilaterally symmetrical.

Striae parallel, slightly radiate towards apices; in smaller valves striae slightly radiate; 23.7-30.4 in 10 µm, areolae discernible in LM (Trobajo et al. 2013).

Fibulate raphe system at valve margin; fibulae rectangular dots and regularly distributed, central fibulae often positioned further apart.

Other features
Auxosporulation: paedogamous, producing auxospores from unpaired gametangia (Mann et al. 2013).

SEM morphology
Central raphe endings straight or slightly deflected to one side, terminal fissures deflected to either side, often deflected backwards. A single row of elliptical areolae in the raphe canal wall on either side of the raphe.


References are given in chronological order.

Grunow A. 1862. Die österreichischen Diatomaceen nebst Anschluss einiger neuen Arten von andern Lokalitäten und einer kritischen Uebersicht der bisher bekannten Gattungen und Arten. Erste Folge. Epithemieae, Meridioneae, Diatomeae, Entopyleae, Surirelleae, Amphipleureae. Zweite Folge. Familie Nitzschieae. 12. Verhandlungen der Kaiserlich-Königlichen Zoologisch-Botanischen Gesellschaft in Wien. 315-472, 545-588 pp; 7 pls. Morphology; Taxonomy; Description
Van Heurck H. 1881. Synopsis des Diatomées de Belgique. Atlas. Ducaju & Cie., Anvers.; pls 31-77 Illustrations
Trobajo R., Mann D.G., Chepurnov V.A., Clavero E., Cox E.J. 2006. Taxonomy, life cycle, and auxosporulation of Nitzschia fonticola (Bacillariophyta). Journal of Phycology. 42: 1353-1372. Biology
Trobajo R., Rovira L., Ector L., Wetzel C.E., Kelly M., Mann D.G. 2013. Morphology and identity of some ecologically important small Nitzschia species. Diatom Research. 28(1): 37-59. Morphology; Taxonomy; Type Illustration;
Mann D.G., Sato S., Rovira L., Trobajo R. 2013. Paedogamy and auxosporulation in Nitzschia sect. Lanceolatae (Bacillariophyta). Phycologia. 52(2): 204-220. Biology; Illustrations; Morphology
Rovira L., Trobajo R., Sato S., Ibáñez C., Mann D.G. 2015. Genetic and physiological diversity in the diatom Nitzschia inconspicua. Eurakyotic Microbiology. 62(6): 815-832. Morphology; Biology; Illustrations
Kelly M.G., Trobajo R., Rovira L., Mann D.G. 2015. Characterizing the niches of two very similar Nitzschia species and implications for ecological assessment. Diatom Research. 30: 27-33. Illustrations; Ecology; Biology
Lobo E.A., Wetzel C.E., Heinrich C.G., Schuch M., Taques F. 2017. Occurrence of a poorly known small-sized Nitzschia species in headwaters streams from southern Brazil. Nova Hedwigia Beiheft. 146: 229-240. Morphology; Illustrations
Shen R., Ren H., Yu P., You Q., Pang W., Wang Q. 2018. Benthic diatoms of the Ying River (Huaihe River Basin, China) and their application in water trophic status assessment. Water. 10: 1013. Ecology

Similar Species

Similar species not published on this website:

This page should be cited as:

Carter C. F., Trobajo R., Mann D.G., Kelly M., Rovira Torres L., Jüttner I., , Nitzschia inconspicua Grunow; 1862; 579. In: Jüttner I., Carter C., Cox E.J., Ector L., Jones V., Kelly M.G., Kennedy B., Mann D.G., Turner J. A., Van de Vijver B., Wetzel C.E., Williams D.M.. Freshwater Diatom Flora of Britain and Ireland. Amgueddfa Cymru - National Museum Wales. Available online at [Accessed:  ].

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Record last modified: 23/03/2021