Encyonopsis
Krammer 1997 Category: Asymmetrical biraphid
TYPE SPECIES: Encyonopsis cesatii Krammer
Image Credit: Ditmar Metzeltin
CLASS: Bacillariophyceae
ORDER: Cymbellales
FAMILY:
- Frustules with slight apical asymmetry
- Stigmoid present (dorsal) or absent
- Striae uniseriate
- Terminal raphe fissures ventrally deflected
Valves of Encyonopsis tend to be only slightly asymmetrical in the apical axis. Some species may be nearly symmetrical to the apical axis and confused with other taxa. Striae are uniseriate. If a stigmoid is present, it will be located on the dorsal side of the central area. The raphe is positioned nearly centrally on the valve. Terminal raphe fissures are ventrally deflected. In contrast to Cymbella, the valves of Encyonopsis lack apical pore fields.
The valve shape of Encyonopsis is more naviculoid and less asymmetrical than many cymbelloid genera. Encyonopsis includes the former Cymbella microcephala complex, C. falaisiensis, C. cesatii, and C. kriegeri.
Cite This Page:
Spaulding, S., Edlund, M., and Metzeltin, D. (2009). Encyonopsis. In Diatoms of the United States. Retrieved May 23, 2013, from http://westerndiatoms.colorado.edu/taxa/genus/Encyonopsis
Contributor: Sarah Spaulding | Mark Edlund | Ditmar Metzeltin - January 2009
Reviewer: Sam Rushforth
Citations
Krammer, K. (1982). Valve morphology and taxonomy in the genus Cymbella C.A. Agardh. Morphology of Diatom Valves 11: 1-299.
Krammer, K. (1997). Die cymbelloiden Diatomeen. Eine Monographie der weltweit bekannten Taxa. Teil 2. Encyonema part., Encyonopsis and Cymbellopsis. Bibliotheca Diatomologica 37:1-469.
Krammer, K. (2003). Cymbopleura, Delicata, Navicymbula, Gomphocymbellopsis, Afrocymbella. Diatoms of Europe. Diatoms of the European Inland Waters and Comparable Habitats 4: 1-530.
Patrick, R.M. and Reimer, C.W. (1966). The Diatoms of the United States exclusive of Alaska and Hawaii, V. 1. Monographs of the Academy of Natural Sciences of Philadelphia 13.
Vouilloud, A.A. Sala, S.E. Avellaneda, M.N. and Duque, S.R. (2010). Diatoms from the Colombian and Peruvian Amazon: the genera Encyonema, Encyonopsis and Gomphonema (Cymbellales: Bacillariophyceae). Revista de Biologia Tropical 58: 45-62.