Chrysaora quinquecirrha has two different body forms during its life cycle. The first form is a polypoid stage, where the organism is a small and sessile stalk, generally only millimeters long. Tentacles facilitate feeding. The polyp may either remain sessile, resembling coral and sea anemones, or it may be free-floating. Due to the polyp’s ability to bud asexually, it can either remain solitary or be colonial. Polyp strobilation, or budding, may lead to the appearance of ephyra, which are small, immature jellies.
From ephyra to adult medusa, C. quinquecirrha has six different stages. These stages are categorized by the change in morphological structure. Two stages involve the growth of the ephyra, while the other four stages are for medusa development. The first four stages seen in species growth have been reproduced in the laboratory, while the last two stages have been recorded from nature. Stage I consists of newly-liberated ephyra, from polyps, which average between two to three and a half millimeters wide from lappet-tip to lappet-tip across the tiny medusa. Stage II is characterized by the presence of primary tentacles, and the development of the oral arms. As the medusa enters stage III, the lappets tend to fold under the medusa, thereby reducing its resemblance to its ephyra stage. Stage IV development is noted by the appearance of secondary tentacles between the primary tentacles. Stage V introduces the growth of 16 tertiary tentacles in the medusa. At this point there are 40 tentacles, and 48 lappets. The last stage, stage VI, is when the medusa has grown to a size of seven or more tentacles and eight or more lappets per octant. As previously mentioned, these last two stages have not been successfully reproduced in the lab, but research has shown that tentacle numbers in adult medusa vary, and are not a dependable taxonomic character in this group of Schyphozoa.
Development - Life Cycle: metamorphosis ; colonial growth
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