RESEARCH ARTICLE
Three new endemic cryptic species revealed by DNA barcoding
of the gobies of the Cayman Islands (Teleostei: Gobiidae)
Benjamin C. Victor
Abstract
A survey
of the mitochondrial DNA marker COI for the gobies
of the Cayman Islands reveals two categories of gobies:
a set of genera that are no different genetically
from other Caribbean populations, including Coryphopterus,
Ctenogobius, Gnatholepis, and Priolepis,
and a set of species that have local mtDNA lineages
quite different from populations elsewhere in the
region, including Elacatinus, Tigrigobius,
and Risor. The cryptic divergent lineages include
some that show distinct phenotypic differences and
are described here as three new endemic species, as
well as others that have divergent local DNA lineages
but no apparent phenotypic differences and are treated
as genovariants, i.e. populations of the same species
with genetic differences. The Cayman Cleaner Goby,
Elacatinus cayman n. sp., is found to be a
close relative of E. evelynae (1.5% divergent;
minimum interspecific distance, K2P), despite the
fact that specimens were originally paratypes of E.
genie (which are 7.5% divergent): their shared
feature of a complete groove above the upper lip is
not apparently a synapomorphy with E. genie
(i.e. not a shared derived character). A neighbor-joining
tree of COI mtDNA sequences for all ten cleaner goby
species of the tropical W. Atlantic is presented.
The Cayman Sponge Goby, Elacatinus centralis
n. sp., differs from E. horsti of the southern
Caribbean by the color of the stripe and snout, and
is further genetically than is the differently marked
Shortstripe Sponge Goby E. chancei (the geographically
intervening relative from the Lesser Antilles). A
neighbor-joining tree of COI mtDNA sequences for all
but two of the striped sponge goby species of the
tropical W. Atlantic is presented. The Cayman Greenbanded
Goby, Tigrigobius harveyi n. sp., has many
more green bands than the Greenbanded Goby of the
Antilles, T. multifasciatus, and differs by
more than 10% in mtDNA sequence; however, it is only
3% different from the Redcheek Goby of Honduras and
the Panamanian Greenbanded Goby. Other species of
Tigrigobius, as well as Risor ruber,
have divergent local DNA lineages, but no apparent
phenotypic differences from other Caribbean populations.
No consistent biogeographical relationships are apparent–
the location of the nearest-neighbor lineages within
the region differs from species to species. A revised
species list for the gobies of the Cayman Islands
is presented and the Kuna Goby, Coryphopterus kuna,
is recorded there for the first time.
|
CITATION:
Victor, B.C. (2014) Three
new endemic cryptic species revealed by DNA barcoding
of the gobies of the Cayman Islands (Teleostei: Gobiidae).
Journal of the Ocean Science Foundation, 12,
25-60.
https://doi.org/10.5281/zenodo.1049119
publication date:22 October
2014
|