Kociolek and Stoermer 1988 Category: Asymmetrical biraphid
BASIONYM: Gomphoneis eriense var. variabilis Kociolek and Stoermer 1988
Contributor: Pat Kociolek - February 2011
Length Range: 25-45 µm
Width Range: 9.5-12 µm
Striae in 10 µm: 10-13 in the center, 14-16 at the poles
Valves are lanceolate-clavate, with a distinctly protracted, broadly rounded head-pole, a robust to linear central portion of the valve and a distinctly rounded footpole. Smaller valves are elliptical-clavate, with the headpole protracted slightly. Striae are radiate at the central portion of the valve and strongly radiate at the poles. The raphe is undulate and lateral. The axial area is narrow, widening slightly towards the central area. A small, barely circular central area with a single stigma is present. The striae have individual areolae observable with DIC or oblique light in the light microscope. Longitudinal lines are distinct near the axial area, less so at the apices. Apical pore fields are present at the footpole.
Gomphoneis eriense var. variabilis is widely distributed throughout western North America.
Basionym: Gomphoneis eriense var. variabilis
Author: Kociolek and Stoermer 1988
Length Range: µm
Striae in 10 µm:
Kociolek, J.P. and Stoermer, E.F. (1988). Taxonomy, ultrastructure and distribution of Gomphoneis herculeana, G. eriense and closely related species (Naviculales: Gomphonemataceae). Proc. Acad. Nat. Sci. Phil. 140: 24-97. http://www.jstor.org/stable/4064935
NADED ID: 36002