The valve has a slightly concave ventral margin and a distinctly convex dorsal margin. Protracted rounded apices slightly recurved toward the dorsal side of the valve. Along the central margin raphe is sometimes apparent. The pores of the median end of the raphe and the central portion curve toward dorsal margin but do not reach the midpoint of the breadth of the valve. fairly distinct openings in the plate subtending raphe. Frustules in girdle view almost rectangular or variably swolen in middle portion. Costae in girdle view have rounded ends, not distinct or capitate. Two to three rows of alveoli between costae.
(Patrick and Reimer 1975).
Type Locality
USA, North Eastern states, Gulfcoast states, South Central states, East Central states, West Central states, Lake states, Plains states, New Mexico, Colorado, Wyoming, Arizona, Utah, Oregon and Washington (Patrick and Reimer 1975).
Synonyms
Navicula turgida Ehr. Phys. Abh. Akad. Wiss. Berlin, for 1830:64 1832 [Described, Ibid., for 1831:80. 1832} Illustrated in Infusionsthierchen, pl. 14, fig. 5 1838. Eunotia turgida Ehr. Ehr., Ber. Akad. Wiss. Berlin, for 1837:45 1837. Cystopleura turgida Ehr. Kuntze, Revisio Gen. Plant., vol. 2, p. 891. 1891.
(Patrick and Reimer 1975).
Ecological distribution
Found in a wide range of habitats including lakes, ponds, rivers, springs or streams, lagoons, pools,oozing areas in rock faces, thermal springs, swamps and terrestrial. It ranges from Acidobiontic to Alkalibiontic. It's Halobion spectrum includes beta range, oligohalobous, indifferent and saproxenous. It is limnobiontic and limnophilous. (Beaver 1981).
Alveoli rows are 7 to 9 in 10 micrometers (Patrick and Reimer 1975).
Note: Husted 1932 found the length to be up to 200 micro meters, Ehrenberg (1830) states they might be 22.5 -112 micrometers long.