title: A new species of Ascocotyle (Trematoda: Heterophyidae) from the South American sea lion, Otaria flavescens, off Patagonia, Argentina.
abstract: We describe a new heterophyid species, Ascocotyle (Ascocotyle) patagoniensis n. sp., based on specimens collected from the intestines of the South American sea lion Otaria flavescens from Patagonia (Argentina). Ascocotyle (A.) patagoniensis n. sp. is distinguished from the other species of the subgenus by the number of circumoral spines, which are arranged in 2 rows of 18 to 23. The new species also differs from the other species in having a gonotyl without papillae. The specimens exhibited the widest seminal receptacle described for a species of this subgenus. Species of the subgenus Ascocotyle usually infect fish-eating birds or mammals in freshwater or brackish habitats. Ascocotyle (A.) patagoniensis n. sp. is the first species of the subgenus described from a marine mammal. However, no metacercariae of Ascocotyle spp. were found in 542 marine teleosts from 20 species collected in the same locality. The life cycle of the marine species from the Ascocotyle -complex infecting pinnipeds remains elusive.
authors.affiliation: Cavanilles Institute of Biodiversity and Evolutionary Biology, University of Valencia, 46980 Valencia, Spain. jesus.s.hernandez@uv.es
authors.forename: Jesús Servando
authors.initials: JS
authors.lastname: Hernández-Orts
authors.forename: Francisco Esteban
authors.initials: FE
authors.lastname: Montero
authors.forename: Enrique Alberto
authors.initials: EA
authors.lastname: Crespo
authors.forename: Néstor Aníbal
authors.initials: NA
authors.lastname: García
authors.forename: Juan Antonio
authors.initials: JA
authors.lastname: Raga
authors.forename: Francisco Javier
authors.initials: FJ
authors.lastname: Aznar
mesh_terms: D000818:Animals; D001118:Argentina; D001267:Atlantic Ocean; D005260:Female; D006578:Heterophyidae / Q000033:anatomy & histology / Q000145:classification* / Q000302:isolation & purification; D007411:Intestinal Diseases, Parasitic / Q000469:parasitology / Q000662:veterinary*; D007422:Intestines / Q000469:parasitology; D008297:Male; D046070:Sea Lions / Q000469:parasitology*; D014201:Trematode Infections / Q000469:parasitology / Q000662:veterinary*