Synopsis of the Grenadier Fishes (Gadiformes; Teleostei) of Taiwan
Author
Iwamoto, Tomio
Section of Ichthyology, California Academy of Sciences, 55 Music Concourse Drive, San Francisco, CA 94118, USA;
Author
Nakayama, Naohide
Laboratory of Marine Biology, Faculty of Science, Kochi University, 2 - 5 - 1 Akebono-cho, Kochi, 780 - 8073, Japan;
Author
Shao, Kwang-Tsao
Research Center for Biodiversity, Academia Sinica No. 128, Sec. 2, Academia Road, Nankang, Taipei 115, Taiwan;
Author
Table, Hsuan-Ching Ho
text
Proceedings of the California Academy of Sciences
2015
2015-04-15
62
3
31
126
journal article
299670
10.5281/zenodo.11512126
522b8de7-880d-40ca-803e-aa5a3a05c5f6
0068-547X
11512126
Hymenogadus gracilis
Gilbert and Hubbs, 1920
Hymenocephalus
(
Hymenogadus
)
gracilis
Gilbert and Hubbs, 1920:522–525
, fig. 31 (
holotype
,
USNM
78227, 96 TL, off s. Luzon,
Philippines
,
13 28ʹ45ʺN
,
121 01ʹ12ʺE
, 162 fm [
296 m
]).— Marshall and Iwamoto
in
Marshall, 1973:602–604
, fig. 31 (
19 spec.
, nw. Pacific, e. and w. Atlantic;
342–618 m
).— Iwamoto and
Merrett, 1997:518
, fig. 20b.—
Shao et al., 2008
: table 2 (
3 spec.
,
Taiwan
[
NET
,
SCS
],
100–950 m
)
Hymenogadus gracilis
:
Okamura, 1970:61–63
, pl. XVIII, text-fig. 27 (
60 spec.
,
91–128 mm
TL; s.
Japan
,
300–500 m
).— Okamura
in
Masuda et al., 1984:94
, pl. 80H (compiled).— Okamura
in
Okamura and Kitajima, 1984:201, 359, fig. 143 (p. 200) (
3 spec.
,
Okinawa
Trough [East
China
Sea],
295–385 m
).—
Chiou et al., 2004b:44–45
, fig. 13 (
2 spec.
, ne.
Taiwan)
.
MATERIAL
EXAMINED
(
6 spec.
).—
NET
:
ASIZP 61229
(1, 118 TL), Nan-fang-ao
;
ASIZP 61230
(1, 120 TL),
Da-xi
;
ASIZP 65565
(1, 60 TL),
Da-xi
;
ASIZP 70278
(1, 105 TL),
Da-xi.
Other specimens:
ASIZP 68334
(2, 96–112 TL),
Aurora
,
357–
367 m.
DISTINGUISHING
FEATURES
.— 1D II9–11; P i14–i17;
V
7–9, usually 8; inner GR-I 14–18 total. Body depth 50–60% HL, about
9–10 in
TL; barbel long, 20–30% HL. Attains about
130 mm
TL.
DISTRIBUTION
.— Probably circumglobal in warm seas, but not central e. Pacific, central e. Atlantic, and central Pacific (but see Remarks), in
300–
450 m.
REMARKS
.— The taxonomic status of the Hawaiian species
H. tenuis
Gilbert and Hubbs, 1917
has yet to be resolved. It may be a synonym of
H. gracilis
.
Okamura (1970:58)
recognized
Hymenogadus
as a full genus with two included species,
H. gracilis
and
H. kuronumai
, and by implication, also
H. tenuis
.
Okamura also placed
H. kuronumai
into its own subgenus
Spicomacrurus
Okamura, 1970
, a taxon that
Iwamoto et al. (2011)
elevated to full generic status.
Hymenogadus gracilis
appears to be more characteristic of oceanic elevations, such as islands, seamounts, and ridges, than to continental landmasses, and the terete body form is suggestive of a more pelagic, active-swimming lifestyle (not benthic, as proposed by
Okamura 1970:60
). Surprisingly, the species was not recorded by Okamura (
in
Okamura et al. 1982
) from the Kyushu-Palau Ridge. Pelagic captures have been reported (Sazonov and Iwamoto 1992) in the upper
300 m
over bottom depths of>
1,000 m
.