Geographic genetic variation in the Coral Hawkfish, Cirrhitichthys oxycephalus (Cirrhitidae), in relation to biogeographic barriers across the Tropical Indo-Pacific
Rolando Quetzalcoatl Torres-García,
Michelle R. Gaither,
D. Ross Robertson,
Eloisa Torres-Hernández,
Jennifer E. Caselle,
Jean-Dominique Durand,
Arturo Angulo,
Eduardo Espinoza-Herrera,
Francisco J. García-De León,
Jonathan Valdiviezo-Rivera,
Omar Domínguez-Domínguez
Affiliations
Rolando Quetzalcoatl Torres-García
Laboratorio de Biología Acuática, Facultad de Biología, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Michoacán, Mexico
Michelle R. Gaither
Department of Biology, Genomics and Bioinformatics Cluster, University of Central Florida, Orlando, Florida, United States
D. Ross Robertson
Smithsonian Tropical Research Institute, Balboa, Panama, Panama
Eloisa Torres-Hernández
Colección Nacional de Peces, Pabellón Nacional de la Biodiversidad, Departamento de Zoología, Instituto de Biología, Universidad Nacional Autónoma de México, Ciudad de México, Mexico
Jennifer E. Caselle
Marine Science Institute, University of California, Santa Barbara, Santa Barbara, California, United States
Jean-Dominique Durand
MARBEC, Université de Montpellier-IRD-CNRS, Montpellier Cedex, France
Arturo Angulo
Escuela de Biología, Museo de Zoología/Centro de Investigación en Biodiversidad y Ecología Tropical (CIBET), y Centro de Investigación en Ciencias del Mar y Limnología (CIMAR), Universidad de Costa Rica, San José, San José, Costa Rica
Eduardo Espinoza-Herrera
Investigación Marina Aplicada, Parque Nacional Galápagos, Puerto Ayora, Isla Santa Cruz, Ecuador
Francisco J. García-De León
Laboratorio de Genética para la Conservación, Centro de Investigaciones Biológicas del Noroeste S. C., La Paz, Baja California Sur, Mexico
Jonathan Valdiviezo-Rivera
Colección de Peces, Instituto Nacional de Biodiversidad, Quito, Pichincha, Ecuador
Omar Domínguez-Domínguez
Laboratorio de Biología Acuática, Facultad de Biología, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Michoacán, Mexico
The Tropical Indo-Pacific (TIP) includes about two thirds of the world’s tropical oceans and harbors an enormous number of marine species. The distributions of those species within the region is affected by habitat discontinuities and oceanographic features. As well as many smaller ones, the TIP contains seven large recognized biogeographic barriers that separate the Red Sea and Indian Ocean, the Indian from the Pacific Ocean, the central and eastern Pacific, the Hawaiian archipelago, the Marquesas and Easter Islands. We examined the genetic structuring of populations of Cirrhitichthys oxycephalus, a small cryptic species of reef fish, across its geographic range, which spans the longitudinal limits of the TIP. We assessed geographic variation in the mitochondrial cytb gene and the nuclear RAG1 gene, using 166 samples collected in 46 localities from the western to eastern edges of the TIP. Sequences from cytb show three well-structured groups that are separated by large genetic distances (1.58–2.96%): two in the Tropical Eastern Pacific (TEP), one at Clipperton Atoll another occupying the rest of that region and the third that ranges across the remainder of the TIP, from the central Pacific to the Red Sea and South Africa. These results indicate that the ~4,000 km wide Eastern Pacific Barrier between the central and eastern Pacific is an efficient barrier separating the two main groups. Further, the ~950 km of open ocean that isolates Clipperton Atoll from the rest of the TEP is also an effective barrier. Contrary to many other cases, various major and minor barriers from the Central Indo-Pacific to the Red Sea are not effective against dispersal by C. oxycephalus, although this species has not colonized the Hawiian islands and Easter Island. The nuclear gene partially supports the genetic structure evident in cytb, although all haplotypes are geographically mixed.
