Moon Jellyfish Anatomy
http://lanwebs.lander.edu/faculty/rsfox/invertebrates/aurelia.html
The moon jellyfish is categorized as a medusa because of its distinct, pulsating bell-shaped body. Like other invertebrates, the moon jelly possesses a hydrostatic skeleton, which is used for support and locomotion. It is composed of a gelatinous-like structure, called the mesoglea, which helps provide support and structure for the animal (Frank and Rinkevich 2013). the mesoglea is in between two protective layers -- the outer epidermis, and the inner gastrodermis. Radial symmetry is present in this invertebrate.
Although these jellyfish do not have a central nervous system, they are able to detect certain stimuli such as touch through a nerve network. They possess very simple eye spots, or ocelli, by which they are able to sense light and dark (Hamner et al. 2004). The tentacles of the moon jelly possess stinging cells called nematocysts. Though not lethal to humans, these nemaotcysts help stun their prey before ingestion (Costello and Colin 1994).
The oral arms on this jellyfish aid in bringing in food to the mouth, which is enclosed by the manubrium. The gastric filaments, which can vary in color, protrude into the edge of the stomach where they secrete digestive enzymes (Dawson 2003). The gastric pouches are radial divisions of the stomach that help to increase surface area.
The radial canals branch off of the ring canal. Both of these structures allow water to move through the jellyfish and can help with movement.
Although these jellyfish do not have a central nervous system, they are able to detect certain stimuli such as touch through a nerve network. They possess very simple eye spots, or ocelli, by which they are able to sense light and dark (Hamner et al. 2004). The tentacles of the moon jelly possess stinging cells called nematocysts. Though not lethal to humans, these nemaotcysts help stun their prey before ingestion (Costello and Colin 1994).
The oral arms on this jellyfish aid in bringing in food to the mouth, which is enclosed by the manubrium. The gastric filaments, which can vary in color, protrude into the edge of the stomach where they secrete digestive enzymes (Dawson 2003). The gastric pouches are radial divisions of the stomach that help to increase surface area.
The radial canals branch off of the ring canal. Both of these structures allow water to move through the jellyfish and can help with movement.
Defining Feature
http://life-sea.blogspot.com/2011/07/life-of-moon-jellyfish.html
As seen in the picture on the left, the moon jelly can easily be distinguished by the 4 horseshoe shapes on its central disc. These structures are the gonads and are under the stomach. Most moon jellies have 4, while it is possible to see some with 5.
