algal bloom

Pseudanabaena

Taxonomy

Order
Synechococcales
Family
Pseudanabaenaceae
Genus
Pseudanabaena

Examples of Pseudanabaena


pseudanabaena

400X total magnification; 10 μm scale bar. Pseudanabaena trichomes indicated by red arrow.

pseudanabaena

400X total magnification; 10 μm scale bar.

Morphology

Trichomes solitary or forming fine mats. Trichomes typically straight or curved, less commonly wavy; usually fairly short, consisting of a small number of cells, or (uncommonly) long, with many cells; usually conspicuously constricted at crosswalls; without firm sheaths, but may have wide, diffluent mucilaginous envelopes. Immotile or facultatively with slow gliding movement. Cells mostly cylindrical with rounded ends, or sometimes nearly barrel-shaped; almost always longer than wide, rarely almost isodiametric; apical cells cylindrical with rounded ends in typical Pseudanabaena, or pointed in subgenera Ilyonema and Skujanema. One or two polar (near crosswalls) aerotopes may be present, though such species may eventually be classified into a separate genus.

Ecology

Recorded from a variety of habitat types: planktic, metaphytic, periphytic, and benthic in various waters; on soils; endogloeic; and in thermal and mineral springs.

References

  • Johansen, J. R., & Komárek, J. (2015). Filamentous Cyanobacteria. In J. D. Wehr, R. G. Sheath, & J. P. Kociolek (Eds.), Freshwater Algae of North America: Ecology and Classification (2nd ed., pp. 146-150). Waltham, MA: Elsevier.
  • Komárek, J. & Anagnostidis, K. (2008). Cyanoprokaryota-2. Teil/Part 2: Oscillatoriales. In B. Büdel, G. Gärtner, L. Krienitz, & M. Schagerl (Eds.), Süßwasserflora von Mitteleuropa (Vol. 19/2, pp. 70-72). Heidelberg, Germany: Spektrum.