The valve ends are almost the same with only slight variations. The Wing canal is very narrow with indistinct projection. The gurtle view is rectangular, the center sometimes squeesed in. The ends are wedge-shaped or sometimes protracted, often with different structure. Length to width ratio is most often 1 to 3 or 1 to 4, very rarely 1 to 5.
(Krammer and Lange-Bertalot 1988), (Hustedt 1930).
Ecological distribution
Found in Lakes, ponds, rivers, springs/ streams, pools, thermal springs, and swamps. pH: Acidobiontic, acidophilous, indifferent, alkailphilous, alkalibiontic. Halobion: Oligohalobous, indifferent, and euryhalobous. Current: Indifferent, rheophilous, and rheobiontic. Special habitat: Tychoplanktonic, and Periphytic. (Beaver 1981).
Synonyms
Surirella ovalis var. angusta (Kutzing 1844)Van Heurck 1885, p. 189, (73/13) Surirella apiculataWm. Smith 1856, p. 88 Surirella angusta var. apiculata Grunow 1862, p. 455, 7/8 Surirella ovalis var. apiculata Otto Muller 1904, pg. 36, 2/10; Otto Muller 1904 in Schmidt et al. 1874 -__, 246/14 Surirella nana var. ? pantocsekiiCleve-Euler 1939, p. 11, fig. 10
?Sur1rella angusta? sensu Schmidt 1875 in Schmidt et al. 1874-__, 23/41 Surirella ovata var. angusta (Kutzing 1844) Cleve-Euler 1952, p. 123, fig. 1566 k, l
Surirella ovata var. smithii Cleve-Euler 1952, p. 123, fig. 1566 m ( e. p.)
Surirella ovata var. smithii f. producta Cleve-Euler 1952, p. 123, fig. 1566 1
Surirella angusta var. genuina Grunow 1862, p. 141
(VanLandingham 1978)