Life Cycle of the Moon Jellyfish (Aurlia aurita)
Aurlia aurita, commonly called the moon jellyfish, got its name because of its translucent circular bell. The moon jellyfish, Aurlia sp., has a smooth, saucer shaped body with eight lobes along the edge of the bell called the bell margin. Along the bell margin are little cilia, which are referred to as marginal tentacles. The marginal tentacles may have a mild sting but is harmless to most humans. There are four horseshoe shaped stomach pouches that make a four-leaf clover in the middle. Directly underneath the food pouches are the gonads. The moon jellyfish also has four white, frilly appendages surrounding the mouth referred to as oral arms. There are both male and female moon jellyfish that reproduce sexually. The distinction between male and female is that "females hold the fertilized eggs, which appear as whitish-gray clumps" (Aurelia), on the oral arms. "During reproduction, the male releases sperm through its mouth into the water column" (Buddin). The sperm swim through the water column into the female's mouth in a kind of hit or miss' style of fertilization. "Female jellyfish pick up strands of sperm floating in the water released from males, and fertilize themselves internally" (MarineBio). After fertilization, a zygote is formed. To maximize fertilization, Aurlia sp. travel in large groups called smucks. As the moon jellyfish journey through the ocean there are greater chances of zygote formation in Aurlia sp. when they travel together in high numbers. Males use the water column to maximize fertilization rates. The oral arms hold the zygotes until they develop into free-swimming larva. Aurelia sp. goes through alternation of generations between the polyp stage and the medusa stage. The...
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