Psammothidium daonense
(Lange-Bertalot in Lange-Bertalot and Krammer) Lange-Bertalot 1999 Category: Monoraphid
BASIONYM: Achnanthes daonensis Lange-Bertalot in Lange-Bertalot and Krammer 1989
SYNONYM(S): Psammothidium grischunum f. daonensis (Lange-Bertalot) Bukhtiyarova and Round
LM scalebar = 10 µm = 80 pixels.
Observations
Contributor: Marina Potapova - August 2010
Length Range: 9-23 µm
Width Range: 4.8-7.5 µm
Striae in 10 µm: 24-30
Description
Valves are elliptical to linear-elliptical. The raphe valve has a linear axial area, which widens into a transapically elliptical, rectangular, or diamond-shaped central area. The raphe is straight, without terminal fissures. The central and terminal raphe ends are slightly expanded externally. The central raphe ends curve toward opposite sides internally. The rapheless valve has a large rhomboid axial area, which has an irregular border. The central area is usually not differentiated from the axial area. Striae are radiate on both valves, 24-30 in 10 µm, interrupted at the valve margin. One row of areolae is present on the mantle of both valves; occasionally a second row of areolae is inserted on the valve margin. Areolae are 36-48 in 10 µm within the striae. The external openings of the areolae are mostly circular, occasionally elongated.
Original Description
Basionym: Achnanthes daonensis
Author: Lange-Bertalot in Lange-Bertalot and Krammer 1989
Length Range: 10-26 µm
Width Range: 5-8 µm
Striae in 10 µm: 27-32
Original Description
Valvae ellipticae ad lineari-ellipticae apicibus late rotundatis non protractis, 10-26 μm longae, 5-8 μm latae. Raphovalva: Raphe filiformis recta, poros terminales influens; pori centrales modice approximate. Area axialis anguste linearis area centralis variabiliter transverse dilatata. Areovalva: Area axialis plus minusque late lanceolata influens in aream centralis rhombicam irregulariter marginatum. Striae transapicales modice radiantes in media parte valvarum usque ad apices, 27-32/10 μm. Quamquam similis a A. marginulata, A. kryophila, A. helvetica satis differt.
Original Images
Cite This Page:
Potapova, M. (2010). Psammothidium daonense. In Diatoms of the United States. Retrieved May 23, 2013, from http://westerndiatoms.colorado.edu/taxa/species/psammothidium_daonense
Species: Psammothidium daonense
Contributor: Marina Potapova
Image Credit: Marina Potapova
- Valves elliptical to linear-elliptical
- Central area on rapheless valve rhomboid with irregular edges
- Raphe straight
Valves are elliptical to linear-elliptical. The raphe valve has a linear axial area, which widens into a transapically elliptical, rectangular, or diamond-shaped central area. The raphe is straight without terminal raphe fissures. The rapheless valve has a large rhomboid axial area with an irregular border. The striae are radiate, 24-30 in 10 µm.
Compare
Psammothidium daonense differs from P. helveticum and P. chlidanos by the large rhomboid axial area on the rapheless valve. Psammothidium daonense has wider and more elliptical valves than P. marginulatum and P. scoticum.
Psammothidium marginulatum
Psammothidium helveticum
Psammothidium chlidanos
Citations
Bukhtiyarova, L. and Round, F. E. (1996). Revision of the genus Achnanthes sensu lato. Psammothidium, a new genus based on Achnanthidium marginulatum. Diatom Research 11: 1-30.
Lange-Bertalot, H. (1999). Neue Kombinationen von taxa aus Achnanthes Bory (sensu lato). Iconographia Diatomologica 6: 276-289.
Lange-Bertalot, H. and Krammer, K. (1989). Achnanthes eine Monographie der Gattung mit Definition der Gattung Cocconeis and Nachtragen zu den Naviculaceae. Bibliotheca Diatomologica 18, 393 pp. Cramer, Berlin, Stuttgart.
Manoylov, K.M. (2007). On some Psammothidium species from rivers in the United States. Diatom Research 22(2): 317–327.
Links & ID's
Index Nominum Algarum (INA)
California Academy of Sciences (CAS)
North American Diatom Ecological Database (NADED)
NADED ID: