Mnemiopsis
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Mnemiopsis is a genus of ctenophore (comb jellies).
They have a body that is oval-shaped and transparent, with four rows of ciliated combs that run along the body vertically and glow green when disturbed at night. They have several feeding tentacles. Unlike cnidarians, Mnemiopsis doesn't sting. Their tentacles can grow up to several yards in length. Its body contains 97% water. They are small animals, having a maximum body length of 60 mm.
Mnemiopsis is a carnivore that consumes copepods, larvae, and fish eggs. It sometimes known to eat its own kind. It also has many predators that feed on it. Many are vertebrates, including species of birds and fish. Some predators are jelly animals, such as cnidarians and other ctenophore species, including sea jellies.
Mnemiopsis is self-fertilizing, which means one individual can make a new population. Eggs and sperm are released into the external area for fertilizing to begin. They have gonads that contain the ovary and spermatophore bunches in their gastrodermis. This animal carries 150 eggs along each meridional canal. The spawning is started at late evening or at 1:00 or 2:00 a.m. The spawning eggs develop a thick cover within 1 minute after touching the seawater. Between 2,000 to 8,000 eggs are produced from large specimens. Egg production starts when the animals reaches 15 mm in length. 20-30 mm is the largest size of reproducing Mnemiopsis.
Mnemiopsis is mostly found in areas of brackish water. It can tolerate a range of salinity, temperature, and water quality. Mnemiopsis appear in Chesapeake Bay from August to September.