Phylogeography, population connectivity and demographic history of the Stoplight parrotfish, Sparisoma viride (Teleostei: Labridae), in the Greater Caribbean

Abstract

Few genetic studies that provide biological, ecological and evolutionary information have been conducted for parrotfishes, including Sparisoma viride, and none has covered the full geographic range of this species. Here, we examine the genetic patterns of the Stoplight parrotfish (S. viride) in the Greater Caribbean and its relationship with the recognized biogeographic provinces in the region. Phylogeographic, population and coalescent analyses were performed to examine the genetic structure and connectivity of S. viride populations throughout its entire range within the Greater Caribbean. Two mitochondrial (control region and coxI) and one nuclear (RHO) markers were used. The Stoplight parrotfish shows high haplotypic diversity (h) and low nucleotide diversity (π) in the control region, and low genetic diversity in coxI and RHO. No evidence of genetic structure was found, indicating a panmictic population throughout the Greater Caribbean with highly symmetrical migration rates among previously defined Caribbean biogeographic provinces. The demographic history estimates indicate events of bottlenecks followed by a population expansion dated at 80,000 years ago (kya) during the Pleistocene epoch. These results suggest that the contrasting environmental conditions that define the Greater Caribbean provinces are not barriers to gene flow for S. viride. The phylogeographic patterns of Stoplight parrotfish could be associated with the biological characteristics of the species (such as extensive pelagic larval duration and use of multiple habitats), historical demographic events and physical conditions of the Greater Caribbean, promoting the genetic homogeneity of the species in the region.