title: The fishes of Cayo Arcas (Campeche Bank, Gulf of Mexico): an updated checklist.
abstract: Cayo Arcas is a small, offshore reef complex on the southwest corner of Campeche Bank, Gulf of Mexico. The only published information (from 2000) on the fishes of that reef refers to 37 species. Here additional information is added, some from unpublished observations during the 1980s, as well as author observations made during 2013 and 2016. These bring the checklist of that reef's fishes up to 162 species. The possible effects of the limited number of fish habitats available at Cayo Arcas on the composition of its fish fauna are discussed. The Indo-Pacific damselfishNeopomacentrus cyanomos(Bleeker, 1856) was first recorded in the Atlantic in mid-2013, on shoreline reefs in the southwest corner of the Gulf of Mexico. Recently reviewed underwater photographs show thatNeopomacentrus cyanomosalso was present at Cayo Arcas in mid-2013, 350 km from the first-record site. Hence it evidently had a substantial population in the southwest Gulf of Mexico in 2013, and must have arrived in there long before that year.
authors.affiliation: Smithsonian Tropical Research Institute, Balboa, Panamá.
authors.forename: D Ross
authors.initials: DR
authors.lastname: Robertson
authors.affiliation: Instituto de Ciencias Marinas y Pesquerías, Universidad Veracruzana, Hidalgo 617, Col. Río Jamapa, C.P. 94290, Boca del Río, Veracruz, México.
authors.forename: Horacio
authors.initials: H
authors.lastname: Perez-España
authors.affiliation: Facultad de Ciencias Naturales, Universidad Autónoma del Carmen, Ciudad del Carmen, Campeche, México.
authors.forename: Enrique Nuñez
authors.initials: EN
authors.lastname: Lara
authors.affiliation: CINVESTAV Unidad Mérida, Mérida, Yucatan, Mexico.
authors.forename: Francisco Puc
authors.initials: FP
authors.lastname: Itza
authors.affiliation: Unidad Multidisciplinaria en Docencia e Investigación de Sisal, Facultad de Ciencias, UNAM, Yucatan, México.
authors.forename: Nuno
authors.initials: N
authors.lastname: Simoes
keywords: Endemic species; invasive damselfish species; reef-fishes; reef-habitat; southwest Gulf of Mexico