Chrysopetalids annelids have been little studied in the Tropical Eastern Pacific (TEP), with only 24 species recorded in the region. Most records are from northwestern Mexico and Costa Rica, leaving many sites along the Tropical Pacific coast of America unexplored. Furthermore, there are species recorded and described from the region with problems in their status, including questionable records, modest illustrations or descriptions, and lost type material. This paper aims to improve the knowledge of this family in the TEP. Almost 290 specimens were revised, provided from five scientific collections, covering 51 sites along the TEP and nearby. Two subfamilies: Calamyzinae and Chrysopetalinae, nine genera and 20 species were determined. Of these, ten species have been previously recorded, three are indeterminable and seven are new species: Paleanotus karlyae n. sp., Arichlidon mucropaleum n. sp., Bhawania bastidai n. sp., Chrysopetalum mexicanum n. sp., C. tovarae n. sp. A new genus is proposed, Bhawatsonia n. gen. which includes two new species, B. fusa n. sp. as its type species, B. nenoae n. sp. and, the new combination and neotype of B. purpurea n. comb. An updated and revised checklist of all chrysopetalids species recorded in the region is included, currently composed of 16 genera, 30 species, and four morphospecies.
author email: christopher.cruz-gomez@hotmail.com