Hydra viridissima
Hydra viridissima | |
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Hydra viridissima | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Cnidaria |
Class: | Hydrozoa |
Order: | Anthoathecata |
Family: | Hydridae |
Genus: | Hydra |
Species: | H. viridissima
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Binomial name | |
Hydra viridissima | |
Synonyms | |
Hydra viridissima is a species of cnidarian which is commonly found in still or slow-moving freshwater[2] in the Northern temperate zone. Hydra viridissima is commonly called green hydra due to its coloration, which is due to the symbiotic green algae Chlorella vulgaris which live within its body.[3] These creatures are typically 10 mm long and have tentacles that are about half of their length.[4] They are strictly carnivorous and typically feed on small crustaceans, insects and annelids. Hydra are normally sessile and live on aquatic vegetation. They secrete mucous to attach to substrate using their basal disc.[4]
Anatomy
Hydra are multi-cellular organisms. They are made up of two layers of epithelial cells and have a
Movement
Although Hydra are
Symbiosis
H. viridissima is currently the only known Hydra species that has a permanent
Growth pattern
Hydra are capable of escaping death by renewing their body tissues. Mortality rates are extremely low and there have been no signs of decline in reproductive rate.[11]
Sensitivity to pollution
Hydra cannot be found in impaired water due to their low tolerance to pollution. They can be used to rank toxicants on level of potential hazard. The simple tubular body and diploblastic membranes, all of the epithelial cells are in constant contact with the environment, this allows for toxic substances being exposed to all body surface.[5] Harsh metals and high levels of those metals can cause mortality. One advantage of being able to reproduce asexually is that they can still reproduce successfully during times where there are high levels of harsh metals.[12]
Reproduction
Hydra are typically
When the Hydra reproduces asexually, buds will be produced that attach to the body wall. The buds are genetically identical clones of the parent. When they are mature they will break free. The parent can possess several buds that are at different stages of development at the same time. The bud once detached from the parent will float until they find some hard substrate to attach to.[2]
References
- ^ a b c "Hydra viridissima Pallas, 1766". World Register of Marine Species.
- ^ a b c Hamrsky, Jan. "Hydra". Life in Freshwater.
- ^ PMID 18660967.
- ^ a b Wright, Jonathan (1997). "Hydra". Hydra: Facts Sheet.
- ^ PMID 22689364.
- ^ "Information on Hydra". www.countrysideinfo.co.uk. Retrieved 2019-04-14.
- PMID 17174108.
- ^ PMID 16351895.
- PMID 4845245.
- .
- S2CID 2009972.
- .
- S2CID 23257641.