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Aulacoseira valida

(Grunow in Van Heurck) Krammer 1991      Category: Centric
BASIONYM: Melosira crenulata var. valida Grunow in Van Heurck 1882
SYNONYM(S): Melosira valida (Grunow in Van Heurck) F.Meister 

Aulacoseira tenella


Bacillaria paradoxa

LM scalebar = 10 µm = 40 pixels.


Contributor: Jonathan English | Marina Potapova - December 2010
Diameter: 7-16 µm
Mantle Height: 10-16 µm
Rows of areolae in 10 µm: 12-17


Frustules are cylindrical and form chains. Valves are 7-16 µm in diameter, with a mantle height of 7-16 µm. The ratio of the mantle height to valve diameter is 0.8-1.5. The mantle has thick walls. The valve face is slightly convex, covered by small areolae. Pervalvar rows of coarse, rectangular areolae are strongly curved to the right (dextrorse), 12-17 in 10 µm. There are 11-17 areolae in 10 µm along the pervalvar row. The mantle areolae are larger near the valve face and gradually become smaller toward the collum. The collum is approximately 1/3-1/5 of the mantle height. The spines are large, spatula-shaped and originate from two pervalvar costae. The ringleiste is solid and wide.

Original Description

Basionym: Melosira crenulata var. valida
Author: Grunow in Van Heurck 1882
Diameter: µm
Rows of areolae in 10 µm:

Original Description

Original Images

Cite This Page:
English, J., and Potapova, M. (2010). Aulacoseira valida. In Diatoms of the United States. Retrieved May 23, 2018, from

Species: Aulacoseira valida

Contributor: Jonathan English | Marina Potapova

Reviewer: Sarah Spaulding


Houk, V., Klee, R. and Passauer, U. (2007). Observations on taxa of Melosira sensu lato among the slides from the Grunow diatom collection in Vienna (Austria). Part. 1. Diatom Research 22(1): 57-80. 10.1080/0269249X.2007.9705695

Krammer, K. (1991). Morphology and taxonomy in some taxa of the genus Aulacoseira Thwaites (Bacillariophyceae). II. Taxa in the A. granulata-. italica- and lirata-groups. Nova Hedwigia 53: 477-496.

Links & ID's

Index Nominum Algarum (INA)

Original INA

California Academy of Sciences (CAS)

Aulacoseira valida CAS

NCBI Genbank Taxonomy

Aulacoseira valida NCBI

North American Diatom Ecological Database (NADED)

NADED ID: 10029

Autecology Discussion