Achnanthidium duthiei

(Sreen.) Edlund 1994      Category: Monoraphid
BASIONYM: Achnanthes duthei Sreen. 1971
SYNONYM(S): Achnanthes duthiei Sreen. | Rossithidium duthiei ('duthii') (Sreen.) Kingston 

Achnanthidium druartii


Achnanthidium eutrophilum

LM scalebar = 10 µm = 80 pixels.


Contributor: Marina Potapova - August 2010
Length Range: 22-32 µm
Width Range: 4.5-5.2 µm
Striae in 10 µm: 14-22 in the center valve, 28-34 at the ends


Valves are linear to linear-lanceolate, with broadly capitate ends. The raphe valve is concave and the rapheless valve is convex. Both valves possess a linear axial area, which widens slightly in the middle portion of the valve. No central area is present. The striae are parallel or very slightly radiate throughout both valves. Striae density on both valves is 14-22 in 10 µm in the middle and 28-34 in 10 µm at the apices. The external openings of the areolae are transapically elongated, appearing as narrow slits. Each stria in the middle part of the valve is composed of 4-5 areolae. The raphe is straight, filiform. The terminal raphe fissures are hooked towards the same side of the valve. Externally, the central raphe ends are teardrop-shaped. Internally, the central raphe ends curve to opposite sides.

Original Description

Basionym: Achnanthes duthei
Author: Sreen. 1971
Length Range: 20-33 µm
Width Range: 4-4.5 µm
Striae in 10 µm: 20-24

Original Description

Original Images

Cite This Page:
Potapova, M. (2010). Achnanthidium duthiei. In Diatoms of the United States. Retrieved April 19, 2018, from

Species: Achnanthidium duthiei

Contributor: Marina Potapova

Reviewer: Sarah Spaulding


Edlund, M.B. (1994). Additions and confirmations to the algal flora of Itasca State Park. II. Diatoms from Chambers Creek. Journal of the Minnesota Academy of Science 59(1):10-21.

Ponader, K. and Potapova, M. (2007). Diatoms from the genus Achnanthidium in flowing waters of the Appalachian Mountains (North America): Ecology, distribution and taxonomic notes. Limnologica - Ecology and Management of Inland Waters 37: 227-241 . 10.1016/j.limno.2007.01.004

Sreenivasa, M.R. (1971). New fossil diatoms from Ontario. II. Achnanthes duthii sp. nov., Achnanthes undulatus sp. nov., and Neidium distincte-punctatum Hustedt var. major var. nov. Phycologia 10(1):79-82.

Links & ID's

Index Nominum Algarum (INA)

California Academy of Sciences (CAS)

Achnanthidium duthiei CAS

North American Diatom Ecological Database (NADED)

NADED ID: 1056

Autecology Discussion