Meridion circulare var. constrictum (Ralfs) Van Heurck; 1880; pl.51
Key references
Williams D.M. 1985. Morphology, Taxonomy and Inter-Relationships of the Ribbed Araphid Diatoms from the Genera Diatoma and Meridion (Diatomaceae: Bacillariophyta). Bibliotheca Diatomologica Vol. 8, J. Cramer, Vaduz. 228 pp.; 27 pls.
Morphology
Shape
Valves clavate with capitate or subcapitate head poles and slightly protracted foot poles, wedge-shaped in girdle view.
Symmetry
Heteropolar, bilaterally symmetrical.
Axial area
Narrow, linear.
Other features
Prominent transapical ribs.
SEM morphology
Small spines can be located along the valve margin.
Uniseriate, unevenly spaced striae with round, occluded external areola openings.
A large transapically elongated rimoportula near the head pole.
A pore field is present at the foot pole.
Valves clavate with capitate or subcapitate head poles and slightly protracted foot poles, wedge-shaped in girdle view.
Symmetry
Heteropolar, bilaterally symmetrical.
Axial area
Narrow, linear.
Other features
Prominent transapical ribs.
SEM morphology
Small spines can be located along the valve margin.
Uniseriate, unevenly spaced striae with round, occluded external areola openings.
A large transapically elongated rimoportula near the head pole.
A pore field is present at the foot pole.
Literature
References are given in chronological order.
Reference |
Citation |
|---|---|
| Ralfs, J. 1843. On the British species of Meridion and Gomphonema. The Annals and Magazine of Natural History. 12: 457-467. | Morphology |
| Van Heurck H. 1881. Synopsis des Diatomées de Belgique. Atlas. Ducaju & Cie., Anvers.; pls 31-77 | Morphology; Taxonomy |
| Williams D.M. 1985. Morphology, Taxonomy and Inter-Relationships of the Ribbed Araphid Diatoms from the Genera Diatoma and Meridion (Diatomaceae: Bacillariophyta). Bibliotheca Diatomologica Vol. 8, J. Cramer, Vaduz. 228 pp.; 27 pls. | Morphology; Taxonomy; Illustrations; |
| Rhode K.M., Pappas J.L., Stoermer E.F. 2001. Quantitative analysis of shape variation in type and modern populations of Meridion Ag. Journal of Phycology. 37: 175-183. | Morphology |
| Stancheva R. 2006. Distribution of resting spores of Eunotia soleirolii and Meridion circulare var. constrictum (Bacillariophyta) in sediments of peat bogs from Mt. Central Sredna Gora, Bulgaria. Ognjanova-Rumenova N., Manoylov K. (eds.) Advances in Phycological Studies, Pensoft, Sofia, Moscow. 111-121 pp | Biology |
This page should be cited as:
Williams D. M., Jüttner I. Meridion circulare var. constrictum (Ralfs) Van Heurck; 1880; pl.51. In: Jüttner I., Carter C., Cox E.J., Ector L., Jones V., Kelly M.G., Kennedy B., Mann D.G., Turner J. A., Van de Vijver B., Wetzel C.E., 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=2422. [Accessed:
].
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Record last modified: 27/12/2020