A New Species of Leidya Corn Alia and Panceri, 1861, and the First Record of the Genus Lobocepon Nobili, 1905, Both from the Eastern Pacific Ocean, with a Review of the Parasites of Grapsid Crabs Worldwide (isopoda, Bopyridae, Ioninae)

Leidya infelix, new species, is described as a parasite of the grapsid crab Pachygrapsus crassipes Randall from the west coast of Baja California, Mexico. Another male belonging to the genus Leidya from the same host and nearly the same locality may belong to the same species, but that is not certain. A lone immature female bopyrid assignable to the genus Lobocepon is recorded as a parasite of Grapsus grapsus (L.) from the Pacific coast of Nicaragua; although probably a representative of a new species, it was not suitable for description. Included are reviews of the genera Leidya Cornalia and Panceri, 1861, and Lobocepon Nobili, 1905, and a tabulation of all species of bopyrid isopods reported to infest grapsid crabs worldwide.