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Craticula accomodiformis

Lange-Bert. 1993      Category: Symmetrical biraphid

REPORTED AS: Navicula accomoda (Krammer and Lange-Bertalot 1986, pg. 128, figs 45: 18-19 ) 

Craticula accomoda


Craticula acidoclinata

LM scalebar = 10 µm = 80 pixels.


Contributor: Ian Bishop | David R.L. Burge - May 2015
Length Range: 31-36 µm
Width Range: 9.9-13 µm
Striae in 10 µm: 23-25 in the center valve, 25-29 in the ends


Valves lanceolate-elliptical with rostrate apices and rounded ends. Striae are parallel at the valve center, becoming weakly radiate along most of the valve length, parallel then weakly convergent near the apices. Stria density increases towards the valve apices. Areolae are fine and not visible in LM. The axial area is narrow. The central area is slightly expanded. The raphe is filiform, with inflated proximal ends. The distal raphe ends sharply deflected to the same direction.

Original Description

Author: Lange-Bert. 1993
Length Range: 28-35 µm
Width Range: 8-11.5 µm
Striae in 10 µm: 20-28

Original Description

Valvae ad instar et quoad strias et areas et raphem generaliter Craticula accomoda valde similes, sed tamen semper maiores, longitudo (24?)28-35(37)µm, latitudo 8-11.5 µm; striae 20-28/10 µm, nodulum centralem versus distantiores positae, 17-25/10 µm (sicut C. accomoda). A C. accomoda differt habitatione conditionibus aquarum non pollutis.

Original Images

Cite This Page:
Bishop, I., and Burge, D. (2015). Craticula accomodiformis. In Diatoms of the United States. Retrieved May 23, 2018, from

Species: Craticula accomodiformis

Contributor: Ian Bishop | David R.L. Burge

Reviewer: Kalina Manoylov


Krammer, K. and Lange-Bertalot, H. (1986). Bacillariophyceae. 1. Teil: Naviculaceae. In: Ettl, H., J. Gerloff, H. Heynig and D. Mollenhauer (eds.) Süsswasserflora von Mitteleuropa, Band 2/1. Gustav Fisher Verlag, Jena. 876 pp.

Lange-Bertalot, H. (1993). 85 Neue taxa und uber 100 weitere neu definierte Taxa erganzend zur Subwasserflora von Mittleuropa. Bibliotheca Diatomologica 27, 454 p. Cramer, Berlin, Stuttgart.

Links & ID's

Index Nominum Algarum (INA)

Original INA

California Academy of Sciences (CAS)

Craticula accomodiformis CAS

North American Diatom Ecological Database (NADED)

NADED ID: 21018

Autecology Discussion

Outside of the U.S, C. accomodiformis occurs in central Europe and the subtropics with mesosaprobic and polysaprobic taxa (Lange-Bertalot 1993). We verified occurrences of C. accomodiformis in the Iowa River, IA and Buffalo Creek, TX, both of which watersheds are heavily dominated by agriculture.


Distribution of Craticula accomodiformis in rivers of the continental U.S. based on the National Water Quality Assessment program. Retrieved 03 June 2015.

Credit/Source: USGS BioData