Achnanthidium eutrophilum

(Lange-Bertalot) Lange-Bertalot 1999      Category: Monoraphid
BASIONYM: Achnanthes eutrophila Lange-Bertalot 1996
SYNONYM(S): Achnanthes eutrophila Lange-Bertalot 

Achnanthidium duthiei

 

Achnanthidium exiguum

LM scalebar = 10 µm = 80 pixels.



Observations

Contributor: Marina Potapova - May 2009
Length Range: 5.4-17.8 µm
Width Range: 2.1-4.0 µm
Striae in 10 µm: 25-35 in the middle of raphe valve

Description

Valves are rhombic-elliptical to rhombic-lanceolate. The raphe valve is concave with a linear axial area. The axial area widens slightly in the middle portion of the valve. Terminal raphe fissures are straight. Central raphe endings are slightly expanded externally, and curved to opposite sides internally. The rapheless valve is convex, with a narrow linear axial area widening slightly in the middle. Striae are radiate throughout both valves, 25-35 in 10 µm. A few central striae are more distant from each other. External openings of areolae are rounded or elliptical and transapically elongated. Each stria in the middle part of the valve contains 4-5 areolae.



Original Description

Basionym: Achnanthes eutrophila
Author: Lange-Bertalot 1996
Length Range: 4–18 µm
Width Range: 3–4 µm
Striae in 10 µm: 24-27

Original Description

Schalen in Umriss regelmässig rhombisch oder rhombisch-elliptisch, bei den grösseren Exemplaren rhombisch-lanzettlisch, mit +/- breit gerundeten, niemals vorgezogen oder kopfig erscheinenden Enden. Länge 4-18 µm, Breite 3-4 µm. R-Schale: Raphe filiform. gerade bis zu den kleinen Terminalporen, niemals mit gekrümmten Terminalspalten. Axialarea schmal- bis linear-lanzettlisch, manchmal zu einer sehr kleinen Zentralarea erweitert. Meistens jedoch ist keine Zentralarea differenziert. Streiffen durchgehend radial, 24-27 in 10 µm. Die zwei mittleren sich gegenüberstehenden Streifen oder auch je zwei bis drei erschinen stärker merkiert und sind weiter entfernt gestellt als die ubrigen. RL-Schale: Zentralarea nicht ausfeprägt, Axialarea und Streifen wie auf der R-Schale.

Original Images


Cite This Page:
Potapova, M. (2009). Achnanthidium eutrophilum. In Diatoms of the United States. Retrieved July 25, 2014, from http://westerndiatoms.colorado.edu/taxa/species/Achnanthidium_eutrophilum

Species: Achnanthidium eutrophilum

Contributor: Marina Potapova

Reviewer: Sam Rushforth

Citations

Lange-Bertalot, H. (1999). Neue Kombinationen von taxa aus Achnanthes Bory (sensu lato). Iconographia Diatomologica 6: 276-289.

Lange-Bertalot, H. and Metzeltin, D. (1996). Indicators of oligotrophy - 800 taxa representative of three ecologically distinct lake types, Carbonate buffered - Oligodystrophic - Weakly buffered soft water. Lange-Bertalot, H. (ed.), Iconographia Diatomologica. Annotated Diatom Micrographs. Vol. 2. Ecology, Diversity, Taxonomy. Koeltz Scientific Books. Königstein, Germany, 2:390 pp.

Links & ID's

Index Nominum Algarum (INA)

California Academy of Sciences (CAS)

Achnanthidium eutrophilum CAS

North American Diatom Ecological Database (NADED)

NADED ID: 1046

Autecology Discussion

Although formation of mucilagenous stalks was never observed in A. eutrophilum, this species might be able to produce stalk as other Achnanthidium species.