Encyonema yellowstonianum

Krammer 1997      Category: Asymmetrical biraphid

Encyonema triangulum


Encyonopsis aequaliformis

LM scalebar = 10 µm = 40 pixels.


Contributor: Sarah Spaulding - August 2010
Length Range: 39-75 µm
Width Range: 17-23 µm
Striae in 10 µm: 10-11


Valves are strongly dorsi-ventral. The dorsal margin is broadly arched, while the ventral margin is slightly expanded. Valves are 39-75 μm long by 17-23 μm wide, as reported by Krammer (1997). The valve apices are rounded. The axial area is relatively broad in the central part, narrowing at the valve ends. The raphe branches are lateral and have a slight arch towards the ventral margin. Each raphe branch is positioned nearly centrally within the axial area. Proximal raphe ends are slightly expanded and dorsally deflected. Distal raphe ends curve slightly to the dorsal margin, but are deflected ventrally near the valve apices. The dorsal striae are divergent. The rows of external dorsal areolae closest to the central area are oval, to irregular and become lineolate. Central dorsal striae 10-11 in 10 μm and distal striae 5 in 5 μm. Central ventral striae 7-8 in 10 μm, and distal striae 6 in 5 μm. The density of areolae within a central, dorsal stria is 8 in 5 μm. The striae continue on the dorsal valve margin.

Original Description

Author: Krammer 1997
Length Range: 39-75 µm
Width Range: 16.8-23 µm
Striae in 10 µm: 9-11

Original Description

Original Images

Cite This Page:
Spaulding, S. (2010). Encyonema yellowstonianum. In Diatoms of the United States. Retrieved April 26, 2018, from http://westerndiatoms.colorado.edu/taxa/species/encyonema_yellowstonianum

Species: Encyonema yellowstonianum

Contributor: Sarah Spaulding

Reviewer: Mark Edlund


Krammer, K. (1997). Die cymbelloiden Diatomeen. Eine Monographie der weltweit bekannten Taxa. Teil 2. Encyonema part., Encyonopsis and Cymbellopsis. Bibliotheca Diatomologica 37:1-469.

Spaulding, S.A., Pool, J., Castro, S. and Hinz, F. (2010). Species within the genus Encyonema Kützing, including two new species Encyonema reimeri sp. nov. and E. nicafei sp. nov. and E. stoermeri nom. nov., stat. nov. Proceedings of the Academy of Natural Sciences of Philadelphia 160(1):57-71. 10.1635/053.160.0107

Links & ID's

Index Nominum Algarum (INA)

California Academy of Sciences (CAS)

Encyonema yellowstonianum CAS

North American Diatom Ecological Database (NADED)


Autecology Discussion