Moon Jellyfish

Aurelia aurita

Habitat & Distribution :  Indo-Pasific Ocean

Diet: Plankton, protozoa,  small fish larvae

Size: Diameter up to 25-40 cm

Lifespan: 6 - 18 months

Description

Aurelia aurita has a transparent, umbrella-like shape known as a bell. Its body structure facilitates movement, generating the thrust needed for swimming. Aurelia aurita appears translucent and is identifiable by four horseshoe-shaped gonads. This jellyfish feeds by capturing prey with its tentacles and bringing it into the body for digestion. Located on the underside of the bell is the manubrium, which functions as the mouth. Aurelia aurita lacks respiratory organs such as gills, lungs, or tracheae; instead, the species breathes through the diffusion of oxygen from the water across the thin membrane covering its body.

Behavior

They are generally found in the water column. These jellyfish are only capable of limited movement, and drift with the current, even when swimming. This jellyfish traps its prey with a current produced by the pulsation of its movement.

Reproduction

They reproduce via a complex, two-stage life cycle involving both sexual and asexual reproduction. This cycle alternates between a sedentary polyp form and a free-swimming medusa (adult) form. During the adult medusa phase, reproduction occurs sexually through the formation of male and female gametes. Fertilization produces a planula larva, which serves as the initial developmental stage of a new individual. The planula larva attaches to a suitable substrate and develops into a polyp. In this phase, reproduction occurs asexually through a process called strobilation, which produces ephyrae. The ephyrae then grow and develop until they reach the adult medusa stage, ready to engage in sexual reproduction once more.

Communication & Perseption

Lacking a central nervous system, they have no means of complex communication. These jellyfish interact with their environment and members of their own species through chemical signals, the sense of touch, and responses to their surroundings.

Predator

Sea turtles, ocean sunfish, and other predatory fish