THE SYNONYMY OF EXCORALLANA KATHYAE MENZIES, 1962, WITH EXCORALLANA TRUNCATA (RICHARDSON, 1899), WITH A REDESCRIPTION OF THE SPECIES (CRUSTACEA, ISOPODA, EXCORALLANIDAE)

ABSTRACT Excorallanakathyae Menzies, 1962, is synonymized with E. truncata (Richardson, 1899) and the species redescribed and figured. Previous authors failed to describe or figure the diagnostic lateral incisions in the pleotelson and the lacinia and molar process of the mandible. The presence of vestigial molar processes and lacinia on the mandibles of excorallanid isopods, previously unreported, supports Menzies et al. (1955) and Brusca's (1981) placement of the excorallanids between the Cirolanidae and the Aegidae in a proposed phylogenetic lineage of flabelliferan isopods. E. truncata ranges through five zoogeographic provinces (Californian, Mexican, Cortezian, Galapagan, and Panamanian); it has been collected at depths ranging from 183 meters to the intertidal zone.