Taxon Account

Psammothidium L. Bukhtiyarova & F.E. Round; 1996; 3

Key references

Bukhtiyarova L., Round F.E. 1996. Revision of the genus Achnanthes sensu lato. Psammothidium, a new genus based on A. marginulatum. Diatom Research. 11(1): 1-30.

Monnier O., Lange-Bertalot H., Hoffmann L., Ector L. 2007. The genera Achnanthidium Kützing and Psammothidium Bukhtiyarova et Round in the family Achnanthidiaceae (Bacillariophyceae): A reappraisal of the differential criteria. Cryptogamie, Algologie. 28(2): 141-158.

Morphology

Frustules slightly bent in girdle view with a raphe system only on one valve (monoraphid); linear, lanceolate or elliptical in valve view, occasionally with broadly rostrate apices; girdle narrow, so that cells most often lie in valve view.

Frustules heterovalvar, isopolar, bilaterally symmetrical (but the raphe is sometimes oblique to the apical axis); bent in girdle view, with the raphe valve on the ‘outside’ of the bend; the raphe valve and pseudoraphe valve are ± similarly patterned.

Striae uniseriate, parallel to slightly radial, fine (relative to the small size of the valves in this genus); areolae small, circular occluded by fine pore plates (hymenes) at their inner apertures.

Axial area narrow and linear, or broader and lanceolate. Central area expanded, sometimes unilaterally, rounded, oval, or an acute-angled fascia or subfascia.

Raphe straight or slightly sigmoid; external central endings simple; internal central endings offset, deflected in opposite directions; terminal fissures absent or turned to opposite sides.

Girdle structure unknown.

A single chloroplast per cell, lying against one side of the girdle and one valve.

Literature

References are given in chronological order.

Reference
Citation
Bukhtiyarova L., Round F.E. 1996. Revision of the genus Achnanthes sensu lato. Psammothidium, a new genus based on A. marginulatum. Diatom Research. 11(1): 1-30. Morphology; Taxonomy; Description; Type Illustration;
Krammer K., Lange-Bertalot H. 2004. Süßwasserflora Mitteleuropas. Bacillariophyceae. 4. Teil. Achnanthaceae. Kritische Ergänzungen zu Achnanthes s.l., Navicula s.str., Gomphonema. Eds Ettl H., Gärtner G., Heynig H., Mollenhauer D., Gustav Fischer Verlag, Stuttgart. 468 pp Taxonomy; Illustrations; Morphology
Monnier O., Lange-Bertalot H., Hoffmann L., Ector L. 2007. The genera Achnanthidium Kützing and Psammothidium Bukhtiyarova et Round in the family Achnanthidiaceae (Bacillariophyceae): A reappraisal of the differential criteria. Cryptogamie, Algologie. 28(2): 141-158. Morphology; Taxonomy; Illustrations;
Enache M.D., Potapova M., Sheibley R., Moran P. 2013. Three new Psammothidium species from lakes of Olympic and Cascade Mountains in Washington State, USA. Phytotaxa. 127(1): 49-57. Morphology; Taxonomy; Illustrations
This page should be cited as:

Mann D. G. Psammothidium L. Bukhtiyarova & F.E. Round; 1996; 3. In: Jüttner I., Bennion H., Carter C., Cox E.J., Ector L., Flower R., Jones V., Kelly M.G., Mann D.G., Sayer C., Turner J. A., Williams D.M.. Freshwater Diatom Flora of Britain and Ireland. Amgueddfa Cymru - National Museum Wales. Available online at https://naturalhistory.museumwales.ac.uk/diatoms/browsespecies.php?-recid=3733. [Accessed:  ].

Image Gallery

Record last modified: 27/12/2020