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heteronereis

noun
het·​ero·​nereis | \¦hetərō+\

Definition of heteronereis 

: a free-swimming dimorphic sexual individual of certain polychaete worms (family Nereidae) characterized by greatly enlarged eyes, enlarged and modified parapodia and other appendages, and more or less complete obliteration of the internal viscera by masses of developing germ cells

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History and Etymology for heteronereis

New Latin, from heter- + Nereis

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