Sorastrum

Sorastrum
Sorastrum spinulosum
Scientific classification Edit this classification
Domain: Eukaryota
Supergroup: Archaeplastida
Clade: Viridiplantae
Division: Chlorophyta
Class: Chlorophyceae
Order: Sphaeropleales
Family: Hydrodictyaceae
Genus: Sorastrum
Kützing
Type species
Sorastrum echinatum
(Meneghini) Kützing
Species

Sorastrum is a genus of green algae in the family Hydrodictyaceae. It is a component of the phytoplankton of freshwater ponds, lakes, and ditches. Sorastrum is common in tropical to temperate regions of the world, but due to its small size it is often overlooked.

The genus was named by Friedrich Traugott Kützing and comes from the Ancient Greek terms σωρός (sōrós, "heap") and ἄστρον (astron, "star").

Description

Sorastrum forms spherical colonies of 8 to 128 cells. Individual cells are kidney-shaped, pear-shaped, or wedge-shaped, or spherical (in Sorastrum sphericum) and attached to a central body of mucilage via gelatinous strands. On each cell there are two to four outwardly pointing spines. Each cell contains a single chloroplast with a one pyrenoid.

Identification of species depends on the size and shape of the cells, particularly the spines.

Reproduction

Reproduction occurs asexually, by zoospores. Zoospores have two flagella each and are formed by the repeated division of the protoplast. Once divided, the zoospores are released from a tear in the mother cell wall. Sexual reproduction has not been observed in Sorastrum, but is presumed to be similar to that of Hydrodictyon and Pediastrum.

References

  1. 1 2 3 4 Guiry, M.D.; Guiry, G.M. "Sorastrum". AlgaeBase. University of Galway. Retrieved 2023-05-23.
  2. ↑ See the NCBI webpage on Sorastrum. Data extracted from the "NCBI taxonomy resources". National Center for Biotechnology Information. Retrieved 2007-03-19.
  3. 1 2 Keshri, Jai Prakash; Mallick, Prasant (2013). "The genus Sorastrum Kützing (Hydrodictyaceae, Sphaeropleales, Chlorophyta) from India, with a new species S. philiposianum". Bangladesh Journal of Plant Taxonomy. 20 (2): 243–249. Bibcode:2013BJPT...20..243K. doi:10.3329/bjpt.v20i2.17399.
  4. ↑ Rabenhorst, L. (1853). Kryptogamen-Flora von Sachsen, Ober-Lausitz, Thüringen und Nord-Böhmen, mit Berücksichtigung der benachbarten Länder: erste Abtheilung: Algen im weitesten Sinne, Leber und Laubmoose. Leipzig: Verlag von Eduard Kummer. pp. i–xx, 1–653.
  5. ↑ Bicudo, Carlos E. M.; Menezes, Mariângela (2006). Gêneros de Algas de Águas Continentais do Brasil: chave para identificação e descrições (2 ed.). RiMa Editora. p. 508. ISBN 857656064X.
  6. ↑ Shubert, Elliot; Gärtner, Georg (2014). "Chapter 7. Nonmotile Coccoid and Colonial Green Algae". In Wehr, John D.; Sheath, Robert G.; Kociolek, J. Patrick (eds.). Freshwater Algae of North America: Ecology and Classification (2 ed.). Elsevier Inc. ISBN 978-0-12-385876-4.