The Pilargidae (Annelida: Polychaeta) of the Pacific Coast of Costa Rica

Thirteen species of Pilargidae (Annelida: Polychaeta) from the subtidal and intertidal Pacific Coast of Costa Rica are reported. A new species, Sigambra vargasi n. sp., is described and an as yet undescribed species, Sigambra sp. A, is also reported. The occurrence of Sigambra tentaculata (Treadwell), Loandalia riojai Salazar-Vallejo, Pilargis berkeleyi Monro, Ancistrosyllis hamata Hartman and Ancistrosyllis jonesei Pettibone are range extensions for these species. The occurrence of Sigambra pettiboneae Hartmann-Schroder, Parandalia tricuspis (Muller), Cabira incerta Webster, Ancistrosyllis papillosa Jones and Ancistrosyllis hartmanae Pettibone are new records of these species for the eastern Pacific Ocean. Synelmis cf albini (Langerhans) is also reported. A taxonomic key to these species is included.