Entomoneis punctulata

(Grunow) K.Osada and H.Kobayasi 1990      Category: Asymmetrical biraphid
BASIONYM: Amphiprora paludosa var. punctulata Grunow in Cleve and Grunow 1880
SYNONYM(S): Entomoneis paludosa var. punctulata (Grunow) Czarn. and Reinke 1982 

Entomoneis paludosa


Envekadea metzeltinii

LM scalebar = 10 µm = 80 pixels.


Contributor: Loren Bahls - February 2012
Length Range: 29-45 µm
Width Range: 7.0-11.4 (valve height, including keel) µm
Striae in 10 µm: 36-40


Frustules are very lightly silicified and come to rest primarily in girdle view, a view which is dominated by two highly arched bilobate keels, one on each valve. The keel lobes are broadly rounded and the keels are only slightly torsioned so that both lobes are more or less in focus at the same time. A row of dots, that may be determined to be fibulae, follow the contour of each lobe a short distance from the keel margin. The short, curved junction line between valve face and keel is restricted to a terminal portion of each lobe of the keel. The cingulum is composed of five or six open bands. Striae are very faint and continuous from the valve face onto the keel without differentiation. The fine structure of the striae cannot be resolved in LM.

Original Description

Basionym: Amphiprora paludosa var. punctulata
Author: Grunow in Cleve and Grunow 1880
Length Range: 46-50 µm
Striae in 10 µm:

Original Description

Original Images

Cite This Page:
Bahls, L. (2012). Entomoneis punctulata. In Diatoms of the United States. Retrieved April 19, 2018, from http://westerndiatoms.colorado.edu/taxa/species/entomoneis_punctulata

Species: Entomoneis punctulata

Contributor: Loren Bahls

Reviewer: Rex Lowe


Cleve, P.T. and Grunow, A. (1880). Beiträge zur Kenntniss der Arktischen Diatomeen. Kongliga Svenska-Vetenskaps Akademiens Handlingar, 17(2): 121 pp., 7 pls.

Czarnecki, D.B. and Reinke, D.C. (1982). Nomenclatural changes among some Kansas diatoms. Transactions of the Kansas Academy of Sciences 85(3): 174-176.

Osada, K. and Kobayasi, H. (1990). Observations on the forms of the diatom Entomoneis paludosa and related taxa. In: Proceedings of the Tenth International Diatom Symposium (H. Simola, ed.), Koeltz Scientific Books, Koenigstein, pp. 161-172.

Witkowski, A., Lange-Bertalot, H. and Metzeltin, D. (2000). Diatom Flora of Marine Coasts I. Iconographia Diatomologica 7: 1-925.

Links & ID's

Index Nominum Algarum (INA)

Original INA

California Academy of Sciences (CAS)

Entomoneis punctulata CAS

NCBI Genbank Taxonomy

Entomoneis punctulata NCBI

North American Diatom Ecological Database (NADED)


Autecology Discussion

There is only one record of Entomoneis punctulata in the Montana Diatom Collection, that from the Redwater River near Circle, Montana. This taxon is likely overlooked in strewn mounts because of its weakly silicified frustules and faint markings. E. punctulata is widespread in marine to brackish waters of the Arctic and temperate regions, including the Baltic Sea (Witkowski et al. 2000). Osada and Kobayasi (1990) report it from several river estuaries in Japan.


Redwater River, McCone County, Montana: home of Entomoneis punctulata.

Credit/Source: Loren Bahls