(Ehrenberg) D.G. Mann 1989 Category: Symmetrical biraphid
SYNONYM(S): Diadesmis bacillum (Ehrenberg) Kützing 1844 | Pinnularia bacillum (Ehrenberg) Ehrenberg 1876 | Schizonema bacillum (Ehrenberg) Kuntze 1898
Contributor: Pat Kociolek - March 2011
Length Range: 30-45 µm
Width Range: 9-10 µm
Striae in 10 µm: 12-14
Valves are linear-elongate with rounded apices. The axial area is straight and bordered by a distinct hyaline conopeum. The raphe is straight with rounded and slightly dilated proximal external ends. The distal ends are deflected onto the margin. T-shaped thickenings are present, but indistinct, near the ends. Striae are radiate and arched, becoming parallel at the apices. Striae are broadly spaced at the center of the valve, and become finer (to 22 in 10 µm) at the ends.
Jahn, R., Mann, D.G., Evans, K.M. and Poulíčková, A. (2008). The identity of Sellaphora bacillum (Ehrenberg) D.G. Mann. Fottea 8: 121–124.
Krammer, K. and Lange-Bertalot, H. (1986). Bacillariophyceae. 1. Teil: Naviculaceae. In: Ettl, H., J. Gerloff, H. Heynig and D. Mollenhauer (eds.) Susswasserflora von Mitteleuropa, Band 2/1. Gustav Fisher Verlag, Jena. 876 pp.
Patrick, R.M. and Reimer, C.W. (1966). The Diatoms of the United States exclusive of Alaska and Hawaii, V. 1. Monographs of the Academy of Natural Sciences of Philadelphia 13.