Oxyneis binalis

(Ehrenb.) Round 1990      Category: Araphid
BASIONYM: Fragilaria binalis Ehrenb. 1854
SYNONYM(S): Tabellaria binalis (Ehrenb.) Grunow 

Orthoseira roeseana


Oxyneis binalis var. elliptica

LM scalebar = 10 µm = 80 pixels.


Contributor: David R.L. Burge | Mark Edlund - June 2016
Length Range: 12-20 µm
Width Range: 2.2-3.7 at the valve center, 6.3-8.4 at the widest part of the valve µm
Striae in 10 µm: 16-18 at center valve


Valves are small and panduriform with a flat valve face. The apices are rounded in larger valves, becoming more broad in smaller valves. A central sternum is faintly evident. Striae are parallel at the valve center, becoming curved and convergent at the apical inflations, finally becoming slightly radiate at the apices. Copulae number 6 to 8 in 10 µm (girdle view), each with a septum at the end opposite the open end of the girdle band. Each valve has a single rimoportula located near one of the apical pore fields, not visible in LM.

Original Description

Basionym: Fragilaria binalis
Author: Ehrenb. 1854
Length Range: µm
Striae in 10 µm:

Original Description

Original Images

Cite This Page:
Burge, D., and Edlund, M. (2016). Oxyneis binalis. In Diatoms of the United States. Retrieved April 25, 2018, from http://westerndiatoms.colorado.edu/taxa/species/oxyneis_binalis

Species: Oxyneis binalis

Contributor: David R.L. Burge | Mark Edlund

Reviewer: Sylvia Lee


Camburn, K.E. and Charles, D.F. (2000). Diatoms of Low-Alkalinity Lakes in the Northeastern United States. Academy of Natural Sciences of Philadelphia, Special Publication 18, 152 pp.

Ehrenberg, C.G. (1854). Mikrogeologie. Einundvierzig Tafeln mit über viertausend grossentheils colorirten Figuren, Gezeichnet vom Verfasser. Voss, Leipzig., Pl. 5, II, fig. 23 (iconotype).

Lewis, F.D. (1865). On extreme and exceptional variations of diatoms, in some White Mountain localities. Proceedings of the Academy of Natural Sciences of Philadelphia 17(1): 7-18.

Round, F.E., Crawford, R.M. and Mann, D.G. (1990). The Diatoms. Biology and Morphology of the Genera. Cambridge University Press, Cambridge, 747 pp.

Siver, P.A. and Hamilton, P.B. (2011). Diatoms of North America: The Freshwater Flora of Waterbodies on the Atlantic Coastal Plain. Iconographia Diatomologica 22.

Links & ID's

Index Nominum Algarum (INA)

Transfer INA
Original INA

California Academy of Sciences (CAS)

Oxyneis binalis CAS

North American Diatom Ecological Database (NADED)

NADED ID: 9107001

Autecology Discussion

Oxyneis binalis can form ribbon-like or zigzag colonies by attachment at the apical pore fields with mucilage pads. Oxyneis binalis has been reported from the northeastern United States and often occurs in lakes with low pH (Lewis 1865, Flower 1989, Camburn and Charles 2000, Siver and Hamilton 2011).


Distribution of Oxyneis binalis in rivers of the continental U.S. based on the National Water Quality Assessment program. Retrieved 13 June 2016.

Credit/Source: USGS BioData & GoogleEarth