Phylogeography and phylogeny of the epineritic cosmopolitan bonitos of the genus Sarda (Cuvier): inferred patterns of intra‐ and inter‐oceanic connectivity derived from nuclear and mitochondrial DNA data

• Published in: Journal of Biogeography
• Main Authors: Viñas, Jordi, Alvarado Bremer, Jaime R., Pla, Carles
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2010
• Subjects: Pacific; North Atlantic; North West Atlantic
• Online Access: http://dx.doi.org/10.1111/j.1365-2699.2009.02225.x; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1365-2699.2009.02225.x; https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1365-2699.2009.02225.x

Abstract Aim To reconstruct the phylogenetic relationships of the four species of the genus Sarda ( Sarda sarda , Sarda orientalis , Sarda australis and Sarda chilensis ) and their phylogeographic history in the context of historical and ecological biogeography. Also, to reconstruct within‐species phylogenetic relationships to test whether the North Atlantic and Mediterranean populations of Atlantic bonito ( S. sarda ) warrant subspecies status, and the validity of the allopatric northern and southern populations of eastern Pacific bonito ( S. chiliensis ), recognized as S. chiliensis lineolata and S. chiliensis chiliensis . Location Representative samples of all four Sarda species collected world‐wide were analysed. Methods Phylogenetic inference was carried out with neighbour‐joining, maximum parsimony and maximum likelihood, employing nucleotide sequences of the mitochondrial DNA (mtDNA) control region I (CR‐I) and of the single‐copy nuclear DNA (nDNA) Tmo‐4c4 gene. Analysis of molecular variance was used on the mtDNA data to estimate the extent of geographic population structuring. Results Gene trees derived from mtDNA and nDNA data yielded concordant phylogenies that support the monophyly of the genus Sarda . The following sibling pairs received strong statistical support: striped bonito ( S. orientalis ) with Australian bonito ( S. australis ), and Atlantic bonito ( S. sarda ) with eastern Pacific bonito ( S. chiliensis ). Furthermore, the origin of S. sarda mtDNA is paraphyletic with respect to S. chiliensis , and these results are indicative of introgression. The analysis of Tmo‐4c4 sequences corroborates the ancestral hybridization between these allopatric species. Comparisons of north‐west Atlantic and Mediterranean populations of S. sarda using mtDNA CR‐I data revealed substantial genetic differentiation. By contrast, no differences between the putative northern and southern allopatric subspecies of S. chiliensis were detected. Main conclusions The monophyly of the genus Sarda as indicated by ...