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Date & Time : 16, November 2024 04:24
Classification
Phylum - Cnidaria
Class - Scyphozoa
Order - Semaestomae
Genus - Aurelia
Common name
Jelly fish
Habit and Habitat
It is a medusoid Jelly fish which is solitary and marine in habit. It mostly lives in warm and temperate latitudes. It feeds on diatoms, protozoans, molluscs, crustaceans and copepodes.
Distribution
It is found along the entire Atlantic coast and Pacific coast.
Identifying Characters
- Body is totally transparent and gelatinous. Mesoglea reflects lightrays with crystal-like clearness.
- Body is made up of about 98% water.
- Body colour is bluish-white or pinkish.
- It is about 30 cm in diameter.
- Body is composed of saucer-shaped umbrella which can be divided into ex-umbrellar and sub-umbrellar surfaces.
- Subumbrellar surfac consists of marginal tentacles, marginal lappet and manubrium.
- Marginal tentacles contain stinging cells.
- Marginal lappets are eight in number and contain sense organs namely tentaculocysts in eight lobes.
- Manubrium hangs down from the centre of subumbrellar surface.
- It is surrounded by four, frilled and long oral arms disposed along four perradii.
- There are four rounded apertures called subgenital pits found in between oral arms.
- Mouth leads to a short gullet which directly opens into the stomach.
- Stomach consists of four interradial gastric pouches. Each gastric pouch gives rise to branched radial canals communicating with circular canal.
- There are three kinds of radial canals: Interradial, Adradial and Perradial
- Locomotion occurs with the help of rhythmic contractions of umbrellar surfaces.
- Aurelia is dimorphic having male and female sexes separately.
- Development is indirect and include planula, scyphistoma and ephyra larva.
- Life cycle exhibits schyphistoma larva as the only polypoid stage. Rest all stages are medusoid.
Video of Aurelia aurita (moon jellyfish) taken at the Monterey Bay Aquarium in Monterey, CA USA, in April, 2003.
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