A new species of artotrogid copepod (Siphonostomatoida), Cryptopontius tanacredii n. sp., associated with the scleractinian coral Pocillopora damicornis (Linnaeus) from Easter Island, is described. The new species can be distinguished from its 20 congeners by the combination of the following six characters: (1) 9-segmented antennule, (2) terminal segment of leg 4 exopod armed with nine elements, (3) second segment of P1 endopod with two setae, (4) two setae on outer lobe of maxillule, (5) inner lobe of the maxillule tipped with two setae, and (6) free segment of P5 present and armed with three setae. This is the first record of the genus from the eastern Pacific and the first occurring in association with a scleractinian coral.