A member in the Order of jellyfish having 8 modified mouth arms armed with nematocysts, rather than the usual tentacles. Each mouth arm has numerous small mouth openings rather than the usual single manubrium.
Commonly known as the blubber, Catostylus is a rhizostome jellyfish with no tentacles but which has 8 modified feeding `arms’ armed with nematocysts. Usually causes a very mild sting with slight skin irritation, although more severe stings have been rarely reported.... catostylus
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