Hexarthra (six arm rotifer)
Hexarthra spp. · Aquatic life
Under the microscope · Photo: CC0
Also called Hexarthra mira, Jumping rotifer, Hexarthra fennica
How to identify Hexarthra (six arm rotifer)
- Microscopic cone shaped soft body about 0.1 to 0.3 mm
- Six muscular arms tipped with feathery bristles
- Jumps quickly by rowing the arms
- No foot
Similar species
Polyarthra also jumps but uses flat paddles in four bunches; Filinia has three long bristles.
Profile
| Season | Summer. |
|---|---|
| Starts | About 65 F and warmer |
| Depth | Open water |
| How it spreads or reproduces | Females clone themselves through the season; tough resting eggs survive drying and travel on birds, wind and equipment |
| Habitat | Warm ponds and reservoirs; also alkaline and slightly salty lakes. |
Why it matters in a lake
A summer grazer of small algae and bacteria, common in warm, alkaline water.
Where it is found
- Idaho: Occasional
- Oregon: Occasional
- Wyoming: Occasional
Classification
| Kingdom | Animalia |
|---|---|
| Phylum | Rotifera |
| Class | Eurotatoria |
| Order | Flosculariaceae |
| Family | Hexarthridae |
| Scientific name | Hexarthra spp. |
Keratella (spined rotifer)
Polyarthra (feather rotifer)
Brachionus (rotifer)
Asplanchna (sac rotifer)
Kellicottia (long spine rotifer)
Filinia (bristle rotifer)
Synchaeta (cold water rotifer)
Trichocerca (rat tail rotifer)
Conochilus (colonial rotifer)
Lecane (flat rotifer)Need a hand?
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