Evolutionary history of the snooks: Phylogeny, biogeography and diversification of the genus Centropomus

Abstract

The snooks (Centropomus spp.) are a group of 13 morphologically similar fish species that are widely distributed off the Atlantic and Pacific coasts of the Americas. This study used a multilocus approach to assess the evolutionary relationships within the genus, and to estimate the divergence times of all the taxa. A total of 105 specimens were analyzed throughout the geographic distribution of the different species. The results of the analyses suggest that the genus Centropomus is composed of four species groups, which originated in the Miocene (~20 Ma) with the common ancestor of the genus probably inhabiting coastal environments in the Americas prior to its diversification. However, most of the cladogenetic events that determined the extant diversity of the genus occurred more recently, during the Pliocene-Pleistocene transition. The samples analyzed here permitted identify three distinct clades within the C. parallelus/C. mexicanus complex, with Centropomus mexicanus likely being restricted to the Gulf of Mexico. The results of the present study also corroborated the existence of two distinct lineages in Centropomus parallelus and identified two previously undescribed lineages in Centropomus viridis. The estimates of divergence times indicated that the formation of the Isthmus of Panama played an important factor in the evolution of the snooks, as weel as oscillations in sea level and ecological adaptations. The type of habitat is related to the evolutionary history of the genus, with the ancestral forms likely inhabiting riverine shoreline environments. Our findings highlight the importance of spatially comprehensive sampling for a better understanding of the evolutionary history of the centropomids, and reinforce the need for a more comprehensive taxonomic review of the genus Centropomus.

Fig 1. The geographic range of the genus Centropomus in the Western Atlantic (orange) and Tropical Eastern Pacific (blue).

The black circles represent the sampling points. The codes refer to the collection localities (S1 Table). This map was compiled by the authors using the QGIS software (Geographic Information System – https://www.qgis.org). Adapted from Rivas [4]. Centropomus irae obtained by the authors represents the genus.

Fig 2. Multilocus topology showing the evolutionary relationships within the genus Centropomus.

The values shown above the nodes indicate the statistical support defined by the Bayesian Posterior Probability (BPP), while those below the nodes represent the bootstrap (BS) values. Centropomus irae obtained by the authors represents the genus.

Fig 3. The maximum credibility tree with the Time to the Most Recent Common Ancestor (TMRCA) of the different snook species and the ancestral geographic range of the genus.

The gray horizontal bars represent the 95% Highest Posterior Density Interval (HPDi) of the estimated age of each node. The values above the nodes are the mean coalescence times, while those below the nodes represent the statistical support defined by the Bayesian Posterior Probability (BPP). The orange circles represent the taxa from the Western Atlantic and the blue circles, those from the Tropical Eastern Pacific. Node boxes show letters corresponding to the likely ancestral range. The map shows the biogeographical provinces used in the BioGeoBEARS analysis, delineated following Araujo et al. [49] and Tosetto et al. [50] for Western Atlantic, and Robertson & Cramer [51] for Tropical Eastern Pacific. This map was produced by the authors using the QGIS software (https://www.qgis.org).

Fig 4. Geographic ranges of the Centropomus species found in the Western Atlantic (orange) and Tropical Eastern Pacific (blue).

The black circles represent the sampling points. These maps were produced by the authors using the QGIS software (https://www.qgis.org). Adapted from Rivas [4].

Fig 5. Phylogenetic arrangements proposed for the genus Centropomus.

Above are the relationships recovered by (A) Fraser [11] based on osteological parameters, (B) Greenwood [12] based on osteological plus external morphology, and (C) Rivas [4] based only external morphology. Below are three distinct molecular phylogenetic arrangements proposed by (D) Tringali et al., [8] based on a single locus (rRNA16S), and Ossa-Hernández et al. [13] and Malcher et al. from a multilocus approach. The orange circles represent the taxa from the Western Atlantic and the blue circles, those from the Tropical Eastern Pacific. The gray vertical bars indicate the groups proposed in each previous study and the colored bars indicate the groups proposed in the present study.