Molecular Phylogeny and Biogeography of the Amphidromous Fish Genus Dormitator Gill 1861 (Teleostei: Eleotridae)

Abstract

Species of the genus Dormitator, also known as sleepers, are representatives of the amphidromous freshwater fish fauna that inhabit the tropical and subtropical coastal environments of the Americas and Western Africa. Because of the distribution of this genus, it could be hypothesized that the evolutionary patterns in this genus, including a pair of geminate species across the Central American Isthmus, could be explained by vicariance following the break-up of Gondwana. However, the evolutionary history of this group has not been evaluated. We constructed a time-scaled molecular phylogeny of Dormitator using mitochondrial (Cytochrome b) and nuclear (Rhodopsin and β-actin) DNA sequence data to infer and date the cladogenetic events that drove the diversification of the genus and to relate them to the biogeographical history of Central America. Two divergent lineages of Dormitator were recovered: one that included all of the Pacific samples and another that included all of the eastern and western Atlantic samples. In contrast to the Pacific lineage, which showed no phylogeographic structure, the Atlantic lineage was geographically structured into four clades: Cameroon, Gulf of Mexico, West Cuba and Caribbean, showing evidence of potential cryptic species. The separation of the Pacific and Atlantic lineages was estimated to have occurred ~1 million years ago (Mya), whereas the four Atlantic clades showed mean times of divergence between 0.2 and 0.4 Mya. The splitting times of Dormitator between ocean basins are similar to those estimated for other geminate species pairs with shoreline estuarine preferences, which may indicate that the common evolutionary histories of the different clades are the result of isolation events associated with the closure of the Central American Isthmus and the subsequent climatic and oceanographic changes.

A biogeographic framework of octopod species diversification: the role of the Isthmus of Panama

“…However, to evaluate the influence of the final seaway closure on divergence and distribution of Atlantic and Pacific sister species, it is important to use a calibration independent of the isthmus formation to avoid circular reasoning in the divergence time interpretation (Marko, 2002;O'Dea et al, 2016). Therefore, molecular phylogenies containing sister species from each side of the IP have been calibrated using the fossils record and/or the molecular evolutionary rate of a particular gene (e.g., Bermingham & Lessios, 1993;Knowlton et al, 1993;Collins, 1996;Bartoli et al, 2005;Bacon et al, 2013;Galván-Quesada et al, 2016).…”

Complete mitochondrial genomes of three Neotropical sleeper gobies: Eleotris amblyopsis, E. picta and Hemieleotris latifasciata (Gobiiformes: Eleotridae)

“…This marine-derived and diadromous component comprises five families (Ariidae, Atherinidae, Gerridae, Eleotridae, and Gobiidae) that, despite representing an important fraction of the diversity of this Neotropical assemblage, is considerably understudied (McMahan et al 2013;Galv an-Quesada et al 2016); particularly relative to the other taxa in the region such as poeciliids and cichlids that have been the focus of many systematic and biogeographic studies (e.g. Martin and Bermingham 1998;Perdices et al 2005;Alda et al 2013;Marchio and Piller 2013;McMahan et al 2017).…”

Sex Chromosomes and Internal Telomeric Sequences in Dormitator latifrons (Richardson 1844) (Eleotridae: Eleotrinae): An Insight into Their Origin in the Genus

“…The distribution of Dormitator has been interpreted as the result of vicariance that followed the break-up of Gondwana, with transisthmian differentiation of two main lineages: one composed of the species sampled in the Western Atlantic basin, and the other represented by the species from the Pacific basin. Although two morphological subspecies have been proposed in this area— Dormitator latifrons mexicanus Ginsburg 1953, restricted to the Pacific coast of Mexico, and Dormitator latifrons latifrons , present in South America—molecular data showed the absence of phylogeographic structure in the Pacific area, that is, the data did not support morphological differentiation ([ 13 ] and references herein).…”