Surirella brebissonii Krammer & Lange-Bertalot; 1987; 82, 85
Krammer K., Lange-Bertalot H. 1987. Morphology and taxonomy of Surirella ovalis and related taxa. Diatom Research. 2(1): 77-95.
English J., Potapova M. 2012. Ontogenetic and interspecific valve shape variation in the Pinnatae group of the genus Surirella and the description of S. lacrimula sp. nov. Diatom Research. 27(1-2): 9-27.
Valves ovate. Headpole evenly rounded, footpole acute, becoming much more rounded in small valves (towards the end of size reduction).
Heteropolar, bilaterally symmetrical.
Radiate in the valve centre, strongly radiate towards the valve ends; areolae not resolvable in LM
Narrow, linear or slightly undulating. The axial area in surirelloid diatoms is not homologous with the axial areas of naviculoid diatoms (it does not contain the raphe)
Raphe slits occupying the whole perimeter of the valve, not visible in LM.
Transapical ribs (which also act as fibulae, linking the mantle to the valve face beneath the raphe) distinct, extending from the margin across a quarter or a third of the valve width, leaving a ±lanceolate area without ribs along the apical axis.
The keel is low and not raised on winglike extension.
Externally transapical ribs extend from the margin to the sternum, with a network of small irregularly placed ribs in between them.
Striae multiseriate with small elongated external and rounded internal areola openings.
Internally every 3rd or 4th transapical rib is strongly thickened and continues from the valve margin beneath the raphe to the valve face; however, the thickening does not continue to the sternum, leaving the central part of the internal surface more or less flat and creating the impression of a lanceolate 'saddle' in LM (depending on the focus). In between the thickened ribs, several smaller fibulae can be seen creating a raphe canal.
Raphe endings straight, slightly expanded, lying at the headpole and footpole.
References are given in chronological order.
|Krammer K., Lange-Bertalot H. 1987. Morphology and taxonomy of Surirella ovalis and related taxa. Diatom Research. 2(1): 77-95.||Morphology; Taxonomy; Description; Type Illustration;|
|Krammer K., Lange-Bertalot H. 1988. Süßwasserflora Mitteleuropas. Bacillariophyceae. 2. Teil. Bacillariophyceae, Epithemiaceae, Surirellaceae. Eds. Ettl H., Gerloff J., Heynig H., Mollenhauer D., Gustav Fischer Verlag, Stuttgart. 596 pp||Morphology; Illustrations; Type Illustration|
|Hofmann G., Werum M., Lange-Bertalot H. 2011. Diatomeen im Süßwasser-Benthos von Mitteleuropa. A.R.G. Gantner, Ruggell. 908 pp||Morphology; Illustrations; Description; Ecology|
|English J., Potapova M. 2012. Ontogenetic and interspecific valve shape variation in the Pinnatae group of the genus Surirella and the description of S. lacrimula sp. nov. Diatom Research. 27(1-2): 9-27.||Morphology; Illustrations;|