(Agardh) Mahoney and Reimer 1986 Category: Asymmetrical biraphid
BASIONYM: Gomphonema lanceolatum Agardh 1831
Contributor: Dan Bogan - June 2013
Length Range: 57.8-146.0 µm
Width Range: 16.6-25.8 µm
Striae in 10 µm: 10-12 in the valve center, 12-14 at the apices
Valves are lanceolate to lanceolate-elliptical with slightly protracted, broadly rounded to attenuate ends. Striae are parallel in the center becoming radiate toward the apices. The elongate central nodule results in a large gap between proximal raphe ends. Internally, helictoglossae are present at the raphe ends, at least 3 µm from valve apex. Apical pore fields are present.
Basionym: Gomphonema lanceolatum
Author: Agardh 1831
Length Range: µm
Striae in 10 µm:
Agardh, C.A. (1831). Conspectus Criticus Diatomacearum. Part 3. Lundae. Litteris Berlingianis. pp. 33-48.
Mahoney, R.K. and Reimer, C.W. (1986). Studies on the genus Brebissonia (Bacillariophyceae). I. Introduction and observations de B. lanceolata comb. nov. In: M. Ricard, ed., Proceedings of the 8th International Diatom Symposium: Koeltz, Koenigstein: 183-190.
Potapova, M. (1996). Epilithic algal communities in rivers of the Kolyma Mountains, NE Siberia, Russia . Nova Hedwigia 63 (3-4): 309-334. 0029-5035/96/0063-0309
Brebissonia lanceolata has been found in several wadeable streams in southwestern Alaska. The pH of these streams ranges from 6.9 to 7.9 with a mean of 7.3 and specific conductance ranges from 19 to 86 µS/cm with an average of 44 µS/cm. It has also been reported from streams and rivers in Eastern Siberia (Potapova 1996).
Credit/Source: Photo by Daniel Rinella