| Characium | |
|---|---|
 | |
| Characium hookeri | |
Scientific classification  | |
| (unranked): | Viridiplantae |
| Division: | Chlorophyta |
| Class: | Chlorophyceae |
| Order: | Sphaeropleales |
| Family: | Characiaceae |
| Genus: | Characium A. Braun in Kützing, 1849 |
| Type species | |
| Characium sieboldii | |
| Species[1] | |
|
See text | |
Characium is a genus of green algae in the family Characiaceae.[1] It is very commonly found in freshwater habitats, where it is attached to phytoplankton or zooplankton.[2]
Description
Characium consists of single or rarely clustered cells. They are attached to a plant or animal substrate (thus epiphytic or epizoic), via a stalk or a circular pad. The cells have diverse shapes, ranging from fusiform to club-shaped or spherical, and are variously straight, hooked, or S-shaped. Cells usually contain a single parietal chloroplast filling the cell, with a central pyrenoid. In some species, the chloroplasts fragment into multiple plastids, each with one pyrenoid.[3] Mature cells have one nucleus (are uninucleate).[4]
Characium reproduces asexually by zoospores. Zoospores have two flagella.[3]
Identification
The genus Characium is similar to Characiopsis, a type of algae in the class Eustigmatophyceae. The two genera are very similar and have been confused in the past;[5] however, Characium produces starch to store excess carbon and thus stains brown to purple in Lugol's iodine solution, while Characiopsis does not.[6] Many other similar segregate genera have been named. These include Deuterocharacium, which differs in having chloroplasts without pyrenoids,[7] and Characiopodium, with multinucleate mature cells.[4]
Identification of species depends on the shapes and sizes of the cell body, as well as the stipe with which the body is attached.[1]
Species list
- C. acuminatum
- C. ambiguum
- C. angustum
- C. astipitatum
- C. braunii
- C. bulgariense
- C. cerassiforme
- C. conicum
- C. epipyxis
- C. giganteum
- C. groenlandicum
- C. guttula
- C. heteromorphum
- C. limneticum
- C. marinum
- C. nasutum
- C. obtusum
- C. ornithocephalum
- C. ovale
- C. polymorphum
- C. prodani
- C. pseudopyriforme
- C. pyriforme
- C. rostratum
- C. saccatum
- C. sieboldii
- C. strictum
- C. substrictum
- C. subulatum
- C. tenue
- C. terrestre
- C. urnigerum
- C. westianum
References
- 1 2 3 Guiry, M.D.; Guiry, G.M. "Characium". AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. Retrieved 2023-09-26.
- ↑ 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.
- 1 2 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.
- 1 2 Ettl, Hanuš; Gärtner, Georg (2013). Syllabus der Boden-, Luft- und Flechtenalgen (in German) (2nd ed.). Springer-Verlag. ISBN 9783642394614.
- ↑ Guiry, M.D.; Guiry, G.M. "Characiopsis". AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. Retrieved 2023-09-26.
- ↑ Matthews, Robin A. (2016). "Freshwater Algae in Northwest Washington, Volume II, Chlorophyta and Rhodophyta". A Collection of Open Access Books and Monographs. Western Washington University. doi:10.25710/fctx-n773.
- ↑ Guiry, M.D.; Guiry, G.M. "Deuterocharacium". AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. Retrieved 2023-10-09.