Ehrenberg 1854 Category: Asymmetrical biraphid
SYNONYM(S): Gomphonema truncatum var. turgidum (Ehrenberg) Patrick 1975
Contributor: Ian Bishop - December 2015
Length Range: 30-49 µm
Width Range: 11.3-15.0 µm
Striae in 10 µm: 10-14
Valves are strongly asymmetric to the transapical axis, with a broad, truncated headpole, nearly as wide as the central inflation. The footpole is narrow and rounded, with a porefield bisected by the distal raphe. The axial area is wide and linear-lanceolate. The raphe is complex and lateral. The central area is small with central striae of variable length, and containing a single isolated stigma. Striae are parallel to weakly radiate, except at the footpole, where they become strongly radiate. Areolae are coarse and easily visible in LM, measuring 21-26 in 10 µm. Voigt discontinuities are often visible.
Author: Ehrenberg 1854
Length Range: µm
Striae in 10 µm:
Ehrenberg, C.G. (1854). Mikrogeologie. Einundvierzig Tafeln mit über viertausend grossentheils colorirten Figuren, Gezeichnet vom Verfasser. Voss, Leipzig., Pl. 5, II, fig. 23 (iconotype).
Patrick, R.M. and Reimer, C.W. (1975). The Diatoms of the United States, exclusive of Alaska and Hawaii, V. 2. Monographs of the Academy of Natural Sciences of Philadelphia 13.
Reichardt, E. (2001). Revision der Arten um Gomphonema truncatum und G. capitatum. In Jahn R., Kociolek, J.P., Witkowski, A. and Compère, P. (Eds.). Lange-Bertalot-Festschrift, Studies on Diatoms. A.R.G. Gantnter Verlag K.G. Ruggell. pp. 187-224.