RESEARCH ARTICLE
Citharichthys
darwini n. sp., a new endemic flatfish from the Galápagos
Archipelago (Teleostei: Pleuronectiformes: Paralichthyidae)
Benjamin C. Victor & Gerard
M. Wellington
Abstract
A
new flatfish, Citharichthys darwini n. sp.,
is described from the shores of Isla Isabela on the
western side of the Galápagos Archipelago. Our recent
collection from Tagus Cove in 1998 is the first record
of the species on Isla Isabela since a series of specimens
were collected at Tagus Cove and nearby by the Allan
Hancock Expedition in 1934. C. darwini is a
dwarf species with adults maturing at around 30 mm
SL and the largest collected less than 60 mm SL. The
new species is distinguished from other eastern Pacific
members of the Citharichthys/Etropus
group by a narrow body (maximum body width 39–45%
SL), medium-sized mouth (upper jaw 31–35% HL), low
dorsal and anal fin-ray counts (D 70–75, A 51–58),
relatively few slender gill rakers (4–7 upper, 8–10
lower), and non-deciduous scales. The barcode mtDNA
COI sequence (used by the Barcode of Life project)
for the new species falls within the broad Citharichthys/Etropus
clade, but is more than 16% divergent from other Citharichthys
in the BOLD barcode database (including most of the
known species). The nearest-neighbor sequence in the
phenetic tree for paralichthyid flatfishes is an Atlantic
species, Citharichthys sp., from the U.S. Virgin
Islands. The species list of flounders and sanddabs
(Paralichthyidae) for the Galápagos Islands is revised
and expanded to six, including Syacium maculiferum,
previously considered a Cocos Island endemic. C.
darwini is apparently the only endemic flatfish
(Paralichthyidae or Bothidae) in the Galápagos Archipelago.
The new species is associated with the cooler water
and coarse black volcanic sands of the recently emerged
western islands in the chain.
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CITATION:
Victor, B.C. & Wellington,
G.M. (2013) Citharichthys darwini n. sp., a
new endemic flatfish from the Galápagos Archipelago
(Teleostei: Pleuronectiformes: Paralichthyidae). Journal
of the Ocean Science Foundation, 6, 19-32.
https://doi.org/10.5281/zenodo.1036811
publication date: 28 February
2013
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