Pliocaenicus
Round & Håkansson 1992 Category: Centric
TYPE SPECIES: Pliocenicus hercynicus Round & Håkansson
CLASS: Coscinodiscophyceae
ORDER: Thalassiosirales
FAMILY:
- Valve face transversely undulate
- Rows of areolae radiate from valve center
- Valve face with central fultoportulae
The valve face of Pliocaenicus has a distinct transverse undulation. Areolae radiate from the valve center in single rows, rather than being organized into groups, or fascicles. A number of fultoportulae are positioned at the center of valve face. Marginal fultoportulae are present between the striae, near the valve/mantle interface. Species in Pliocaenicus lack areolae on the valve mantle, below the marginal strutted process.
Pliocaenicus shares a number of features with Cyclotella, Cyclostephanos, and Stephanodiscus. Many of the distinguishing features are visible in SEM. This genus is known from oligotrophic lakes in Siberia, Mongolia, western North America and Pleistocene deposits in Alaska.
Cite This Page:
Spaulding, S., and Edlund, M. (2008). Pliocaenicus. In Diatoms of the United States. Retrieved June 20, 2013, from http://westerndiatoms.colorado.edu/taxa/genus/Pliocaenicus
Contributor: Sarah Spaulding | Mark Edlund - December 2008
Citations
Cremer, H. and Van de Vijver, B. (2006). On Pliocaenicus costatus (Bacillariophyceae) in Lake El’gygytgyn, East Siberia. European Journal of Phycology. 10.1080/09670260600621932
Flower, R.J., Ozorina, S.P., Kuzima, A. and Round, F.E. (1998). Pliocaenicus taxa in modern and fossil material mainly from eastern Russia. Diatom Research 13: 39-62.
Khursevich, G. and Stachura-Suchoples, K. (2008). The genus Pliocaenicus Round & Håkansson (Bacillariophyta): Morphology, taxonomy, classification and biogeography. Nova Hedwigia 86: 419-444.
Round, F.E. and Håkansson, H. (1992). Cyclotelloid species from a diatomite in the Harz mountains, Germany, including Pliocaenicus gen. nov. Diatom Research 7: 109-125.