title: A new species of the zephyrinid nudibranch genus Janolus (Mollusca: Nudibranchia) from North America and Costa Rica.
abstract: A new species of zephyrinid nudibranch of the genus Janolus Bergh 1884 is described from the Pacific Coast of North America and Costa Rica. J. anulatus sp. nov. differs from other species of Janolus by its external and internal morphology. J. anulatus has a brown or white body with pink, white, and brown spots, smooth papillae epithelium at the base and papillated in the distal part, unbranched digestive gland ducts, smooth jaws, and smooth rachidian and lateral teeth. The species is compared with other species from the Panamic Province and the Western Atlantic. A new extension range of J. barbarensis is documented.
authors.affiliation: Museo de Zoología, Escuela de Biología, Universidad de Costa Rica, San Pedro de Montes de Oca, San José, Costa Rica. ycamacho@biologia.ucr.ac.cr
authors.forename: Yolanda E
authors.initials: YE
authors.lastname: Camacho-García
authors.forename: Terrence M
authors.initials: TM
authors.lastname: Gosliner
mesh_terms: D000818:Animals; D003364:Costa Rica; D049851:Gastropoda / Q000033:anatomy & histology* / Q000145:classification*