Hydrianum
| Hydrianum | |
|---|---|
 | |
| Hydrianum ovale | |
Scientific classification  | |
| Kingdom: | Plantae |
| Division: | Chlorophyta |
| Class: | Chlorophyceae |
| Order: | Chlamydomonadales |
| Family: | incertae sedis |
| Genus: | Rabenhorst, 1868 |
| Type species | |
| Hydrianum ovale Rabenhorst[1] | |
| Species[1] | |
| |
| Synonyms | |
| |
Hydrianum is a genus of green algae, in the order Chlamydomonadales. It is found in freshwater habitats such as marshes and bogs, as an epiphyte on plants or other algae.[1] It is common, but most likely overlooked due to its similarity with similar genera such as Characium.[3]
Description
Hydrianum consists of solitary or clustered cells attached to a substrate, via a mucilaginous pad or a stipe. Cells are cylindrical, oval, or spindle-shaped; in some species they are distinctly curved. Cells are uninucleate (with a single nucleus), they contain a single parietal chloroplast (or multiple when older). Pyrenoids are generally absent but may be present in a few species.[1]
Asexual reproduction occurs via the formation of zoospores; the zoospores are released through a rupture near the apex of the cell wall, while one zoospore stays behind and develops into a new vegetative cell. Zoospores have two flagella and a single chloroplast. After swimming, the zoospores settle and develop into a new cell. Sexual reproduction has not been observed in this genus.[1]
Members of Hydrianum with a pyrenoid can be confused with Characium, but in Hydrianum the zoospores exit subapically or apically, while in Characium the zoospores exit through a lateral opening. Additionally, in Hydrianum a zoospore may remain in the sporangium and develop into a new cell. The genus is also similar to Characiopsis, which generally lacks pyrenoids, but is unrelated.[3]
References
- ^ a b c d e Guiry, M.D.; Guiry, G.M. "Hydrianum". AlgaeBase. University of Galway. Retrieved 2022-02-25.
- ^ Guiry, M.D.; Guiry, G.M. "Chlororhabdion". AlgaeBase. University of Galway. Retrieved 2024-11-30.
- ^ a b Komárek, J.; Fott, B. (1983). Chlorophyceae (Grünalgen), Ordnung Chlorococcales. Das Phytoplankton des Süßwassers (in German). E. Schweizerbart'sche Verlagsbuchhandlung. p. 1044.
External links