Kurtkrammeria

Bahls 2015      Category: Asymmetrical biraphid
TYPE SPECIES: Kurtkrammeria weilandii (Bahls) Bahls

Krasskella

 

Lemnicola

Image Credit: Loren Bahls

CLASS: Bacillariophyceae
  ORDER: Cymbellales
    FAMILY: Cymbellaceae

  1. Valves naviculoid, slightly dorsiventral
  2. Areolae slit-like or crescent shaped
  3. Striae convergent at the apices
  4. 1-3 dorsal stigmata present, or stigma absent
  5. Apical pore fields present or absent

Valves are naviculoid and slightly dorsiventral, symmetric to the transapical axis and asymmetric to the apical axis. The raphe is centrally located. Areolae in the striae are slit-like or crescent shaped and oriented with their long axes parallel to the apical axis. Transapical striae are radiate near the valve center, becoming parallel, then convergent near the apices. A more or less well developed apical pore field may be present at both ends of the valve, or pore fields may be absent.

In Encyonopsis species, areolae are round or oblong, rather than slit-like or crescent shaped, with the long axes oriented in a transapical direction. In Encyonopsis, terminal striae are radiate or parallel, but not convergent. Stigmata and apical pore fields are absent in Encyonopsis. In other features, Kurtkrammeria is similar to Encyonopsis. Both genera have naviculoid and slightly dorsiventral valves with centrally located raphes. In both genera the proximal raphe ends are inclined toward the dorsal side of the valve and distal raphe fissures are deflected ventrally.

Kurtkrammeria includes the former Encyonopsis aequalis, E. neoamphioxys, E. stodderi, and E. subspicula.

Cite This Page:
Bahls, L. (2015). Kurtkrammeria. In Diatoms of the United States. Retrieved December 11, 2017, from http://westerndiatoms.colorado.edu/taxa/genus/kurtkrammeria

Contributor: Loren Bahls - December 2015
Reviewer: Sarah Spaulding - December 2015