Crabs (Crustacea, Decapoda) from the Sea off East and Southeast Asia collected by the RV Hakuhō Maru (KH- 72 - 1 Cruise) 1. Sulu Sea and Sibutu Passage
Author
Takeda, Masatsune
Department of Zoology, National Museum of Nature and Science, 4 - 1 - 1 Amakubo, Tsukuba, Ibaraki 305 - 0005, Japan E-mail: takeda @ kahaku. go. jp (MT) / h-komatu @ kahaku. go. jp (HK)
takeda@kahaku.go.jp
Author
Ohtsuchi, Naoya
International Coastal Research Center, Atmosphere and Ocean Research Institute, The University of Tokyo, 1 - 19 - 8 Akahama, Otsuchi, Iwate 028 - 1102, Japan E-mail: ohtsuchi @ g. ecc. u-tokyo. ac. jp
ohtsuchi@g.ecc.u-tokyo.ac.jp
Author
Komatsu, Hironori
Department of Zoology, National Museum of Nature and Science, 4 - 1 - 1 Amakubo, Tsukuba, Ibaraki 305 - 0005, Japan E-mail: takeda @ kahaku. go. jp (MT) / h-komatu @ kahaku. go. jp (HK)
takeda@kahaku.go.jp
text
Bulletin of the National Museum of Nature and Science. Series A, Zoology
2021
2021-05-21
47
2
65
97
journal article
10.50826/bnmnszool.47.2-65
2434-091X
12759907
09E0EFF3-ABE7-43D7-AA85-DA3BF08E47B9
Dicranodromia foersteri
Guinot, 1993
(
Figs. 4–5
)
Material examined.
RV
Hakuhō Maru
KH-72-1 cruise, sta. 20 (Sibutu Passage;
05°40.9′N
,
119°46.3′E
–
05°43.1′N
,
119°47.0′E
;
460–514 m
deep); otter trawl; 10 June, 1972; 1˂ (ovig.), NSMT-Cr 28966
.
Measurements
. CB
33.3 mm
; CL in median line,
33.7 mm
; length of rostrum,
3.3 mm
; length of first ambulatory leg,
62.2 mm
; diameter of egg,
2.2 mm
.
Remarks.
In the ovigerous female at hand, the carapace was cracked into two, with somewhat damaged posterior part (
Fig. 4A
), but there is no problem to depict the species characteristics. The key prepared by Guinot (1995) was used to identify the present specimen, with combination of the characters that 1) the carapace dorsal surface is smooth and not disguised by the setae of variable lengths, 2) the palm is granulated for its whole outer surface, 3) the last leg is rather long and slender. As a result, it was keyed out to
D. martini
Guinot, 1995
from the
Philippines
, or
D. foersteri
Guinot, 1993
from the Chesterfield Islands,
New Caledonia
and
Vanuatu
. Some differences between the two species were mentioned by Guinot (1995), viz. the antero-external tooth of the basal antennal segment is strong and long in
D. martini
(stout and short in
D. foersteri
), the infra-orbital tooth is large and bifid in
D. martini
(pointed and simple in
D. foersteri
), the epistome is armed with some sharp granules in
D. martini
(unarmed in
D. foersteri
), the anterior margin of the buccal frame is fringed with spinules in
D. martini
(only indistinctly dentated in
D. foersteri
), and the dactyli of the first two ambulatory legs are relatively long and subequal to the carpi in
D. martini
(comparatively short and slightly shorter than the carpi in
D. foresteri
). These differences are appli- cable to the ovigerous female examined, and the different length and stoutness of the ambulatory legs are the important criteria among the differences. It is recorded at present that the ambulatory dactyli are half as long as the propodi in
D. foersteri
, rather than two-thirds in
D. martini
, although
Ng and Naruse (2007)
found some variations in the length of the ambulatory carpi in
C. martini
.
Ng and McLay (2005)
described a new species,
D. danielae
from Balicasag Island in the
Bohol
Sea,
200–300 m
deep, on the comparison with
D. doederleini
Ortmann, 1892
and
D. martini
Guinot, 1995
. In
D. danielae
, however, the outer surface of the chela is smooth, the external orbital tooth is armed with spinules, the posterior margin of the epistome is spinulate, and the meri and propodi of the subdorsal legs are proportionately shorter. In
D. danielae
, the outer margin of the frontal lobe is straight, differing from the weakly concave margin of
D. doederleini
and
D. martini
.
Fig. 4.
Dicranodromia foersteri
Guinot, 1993
, ovigerous female (NSMT-Cr 28966. CB 33.3 mm; CL 37.0 mm including rostrum) in dorsal (A) and ventral (B) views.
Distribution.
This species has been previously recorded from
Vanuatu
, the Chesterfield Islands and
New Caledonia
,
495–660 m
deep (Guinot, 1993, 1995), and the close congener,
C. martini
, from the Sulu and Bohol Seas,
437–930 m
deep (Guinot, 1995;
Ng and Naruse, 2007
).