Paronatrema guillerminae n. sp. (Digenea: Syncoeliidae) parasite of the blue shark Prionace glauca (Linnaeus) (Elasmobranchii: Carcharhinidae) off the western coast of Baja California Sur, Mexico

Nine specimens of Paronatrema guillerminae n. sp. were collected from the gills of the blue shark Prionace glauca (Linnaeus) captured by artisanal fishing in the locality of Punta Belcher (Magdalena Bay), Baja California Sur, Mexico. Paronatrema guillerminae n. sp. is proposed as a new species because it presents distinctive characteristics within the genus Paronatrema (Dollfus), in the following morphological traits: body size, (larger than congeneric species), tegument with scale-like extensions, ovary shape (rounded), and testes number (more than 200). The new species is described herein.