nauplius

noun, plural nau·pli·i [naw-plee-ahy] /ˈnɔ pliˌaɪ/.

1. (in many crustaceans) a larval form with three pairs of appendages and a single median eye, occurring usually as the first stage of development after leaving the egg.

noun plural -plii (-plɪˌaɪ)

1. the larva of many crustaceans, having a rounded unsegmented body with three pairs of limbs