Journal of the
Ocean Science Foundation

An open-access free online peer-reviewed Marine Biology Journal, since 2008.

published by the Ocean Science Foundation

 
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RESEARCH ARTICLE

Hypoplectrus floridae n. sp. and Hypoplectrus ecosur n. sp., two new Barred Hamlets from the Gulf of Mexico (Pisces: Serranidae): more than 3% different in COI mtDNA sequence from the Caribbean Hypoplectrus species flock

Benjamin C. Victor

Abstract

The species flock of hamlets of the genus Hypoplectrus from the coral reefs of the tropical western Atlantic contains more than a dozen morphs distinguished by color pattern alone. Thus far, they have been characterized by a high level of genetic uniformity, raising many questions about whether they represent true species, incipient species, or color variants. However, DNA barcoding of the COI mtDNA gene from two otherwise unremarkable marking variations of the Barred Hamlet from the Gulf of Mexico and Florida reveals two separate relatively deep lineages more than 3% sequence-divergent from the large homogenous clade that contains all other barcoded Hypoplectrus, including Caribbean Barred Hamlets H. puella and seven other species, collected from all quadrants of the Caribbean Sea. The two new clades differ by more than 1.2% in the barcode sequence from each other and have distinctive marking patterns and are therefore described as new species. Hypoplectrus floridae n. sp. is found in the eastern Gulf of Mexico and South Florida and is characterized by a pair of symmetrical dark spots at the base of the caudal fin along with a break in the mid-body narrow bar. Hypoplectrus ecosur n. sp. has, at present, been collected only at Contoy, at the northern tip of the Yucatan peninsula, and is distinguished by the same pair of dark spots at the base of the caudal fin as well as a series of additional dark spots along the upper caudal peduncle and below the base of the soft dorsal fin. The remarkable combination of minor marking differences with large genetic differences not only underscores the inconsistency of phenotypic and genotypic divergence in some lineages of reef fishes, but provides philosophical support for the validity of species-level recognition for at least some members of these species flocks. Further documentation of the distribution and consistency of these mtDNA lineages is needed to resolve the complex phylogenetic processes taking place at the intersection of the biogeographic zones of the Caribbean, Florida, and the Gulf of Mexico.

     

CITATION:

Victor, B.C. (2012) Hypoplectrus floridae n. sp. and Hypoplectrus ecosur n. sp., two new Barred Hamlets from the Gulf of Mexico (Pisces: Serranidae): more than 3% different in COI mtDNA sequence from the Caribbean Hypoplectrus species flock. Journal of the Ocean Science Foundation, 5, 2–19.

http://dx.doi.org/10.5281/zenodo.1012591

publication date: 30 August 2012