A new deep-water hermit crab species of the family Parapaguridae, Oncopagurus oimos, is described from Moruroa (French Polynesia, Tuamotu Archipelago). The new species is distinguished primarily by its distinctive color pattern (still visible in alcohol-preserved specimens after one year), and consisting of broad stripes on the left cheliped and ambulatory legs. Other diagnostic characters of the new species are: (1) males lacking first pleopods and having reduced unpaired left second pleopods; (2) slender left cheliped; (3) rounded mesial face of the right chela. The new species is compared to another congeneric species, O. tuamotu Lemaitre, 1994 that also occurs in French Polynesia, as well as to other species of the genus in which males lack first pleopods.
deep-water hermit crab, new species, Parapaguridae, Oncopagurus, French Polynesia, Tuamotu Archipelago.