Grunow 1860      Category: Asymmetrical biraphid
TYPE SPECIES: Brebissonia boeckii (Ehrenberg) O'Meara




CLASS: Bacillariophyceae
  ORDER: Cymbellales
    FAMILY: Cymbellaceae

  1. Striae biseriate
  2. Proximal raphe ends relatively widely separated

Valves are rhombic-lanceolate or lanceolate and slightly isopolar. The valve face is flat and the mantle is shallow. Striae are biseriate. Robust transapical ribs are present. The proximal raphe ends are expanded and internally deflected to the primary side of the valve. The distal raphe fissure is long and bent. Internally, a prominent helictoglossa is present. Copulae are open.

Brebissonia is considered to be closely related to Cymbella, as based on plastids, raphe structure and formation of stalks growth habit. A single plastid is present, positioned against on side of the girdle and extending beneath both valves. Cells produce mucilage stalks, which are joined in colonies.

The genus is not common, but may be locally abundant in brackish or marine waters.

Cite This Page:
Spaulding, S., and Metzeltin, D. (2013). Brebissonia. In Diatoms of the United States. Retrieved April 25, 2018, from

Contributor: Sarah Spaulding | Ditmar Metzeltin - June 2013