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n.1.(Zool.) A genus of transparent marine annelids which swim actively at the surface of the sea. They have deeply divided or forked finlike organs (parapodia). This genus is the type of the order, or suborder, Gymnocopa.
Webster's Revised Unabridged Dictionary, published 1913 by G. & C. Merriam Co.
References in periodicals archive ?
"We're still addressing the kinds of observations he was making," Haddock said."There's still a lot to learn." (Cover photo: Tomopteris, a genus of sea worms that emits blue light, but one species can produce yellow.)
The least transparent tissues were from the pelagic gastropods (excluding Clione) (17%) and Tomopteris (9.1%).