Adult male and female, nauplius 1 and 2, and preadult 1 and 2 stages of Paralebion elongatus Wilson, 1911 (Copepoda: Euryphoridae) are redescribed and described, respectively, from specimens collected from aquarium-held reef whitetip sharks (Triaenodon obesus) captured in Hawaiian waters. A circular area of villiform papillae between the frontal plates in the adult stage supports evidence that this region does not have a chemosensory function. Time-of-capture data suggest that P. elongatus can complete its life cycle in a captive environment