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.
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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.
https://doi.org/10.5281/zenodo.1012591
publication date: 30 August
2012
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