Spirotrich
Spirotrichs Temporal range:
| |
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Euplotes, a spirotrich | |
Scientific classification | |
Domain: | Eukaryota |
Clade: | Diaphoretickes |
Clade: | SAR |
Clade: | Alveolata |
Phylum: | Ciliophora |
Subphylum: | Intramacronucleata |
Infraphylum: | Spirotrichia |
Class: | Spirotrichea Bütschli 1889[2] |
Typical subclasses | |
Hypotrichia Licnophoria Oligotrichia Phacodiniidea Protohypotrichia |
The spirotrichs are a large and diverse group of ciliate protozoa.[3] They typically have prominent oral cilia in the form of a series of polykinetids, called the adoral zone of membranelles, beginning anterior to the oral cavity and running down to the left side of the mouth. There may also be one or two paroral membranes on its right side. The body cilia are fused to form polykinetids called cirri in some, and are sparse to absent in others.
Forms with cirri are common throughout soil, freshwater, and marine environments. Individuals tend to be flattened, with cirri confined to the ventral surface. These are variously used for crawling over objects, acting as feet, swimming, or assisting in food capture. They are generally divided into hypotrichs and stichotrichs, but were originally all considered hypotrichs.
Forms with sparse or absent body cilia tend to be smaller and are mostly marine, but a few are common in freshwater. Again, they are generally divided into oligotrichs and choreotrichs, but were originally all considered oligotrichs. The latter group includes the tintinnids, which produce loricae or shells and are the predominant fossil ciliates.
As first defined by
The remaining spirotrichs form a
See also
References
- PMID 21810989.
- ISBN 978-1-4020-8239-9.
- ISBN 978-1-4020-8239-9.