1. No category

NAOSITE: Nagasaki University's Academic Output SITE
Title
Studies on Holocephali―I On the morphology and ecology of Chimaera
phantasma, and male reproductive organs.
Author(s)
Malagrino, Giovanni; Takemura, Akira; Mizue, Kazuhiro
Citation
長崎大学水産学部研究報告, v.42, pp.11-19; 1977
Issue Date
1977-02
URL
http://hdl.handle.net/10069/30700
Right
This document is downloaded at: 2015-01-31T21:19:16Z
http://naosite.lb.nagasaki-u.ac.jp
Bull.
Fac. Fish.
Nagasaki
No. 42 11∼19
Univ.,
Studies
On the
Giovanni
on
Holocephali-I
morphology
phantasma,
and
11
(1977)
and
male
MALAGRINO, Akira
ecology
of Chimaera
reproductive
TAKEMURA, and
organs.*1
Kazuhiro
MIZUE.*2
The morphological characters and ecology of Chimaera phantasma and male's reproductive
organs were investigated. Specimens (115 males, 191 females) were collected at the Nagasaki
Fish Market or caught by the authors themselves from September 1975 to October 1976. The
variation of proportion percentages compared with body length is not remarkable and the
growth curves of the male and female are indicated by the following formula:
Male
: W = 0.1913L2.2269
Female : W = 0.0376L2.6349
It was observed that the male's condition factor increases with the increment of body
length, but no seasonal variation of this factor could be observed. In females no variations
of any kind were observed. The diet is basically formed by Crustacea, especially crabs, and
teeth consist of three pairs of dental plates.
The posterior clasper is trifurcated and has no remarkable appendices. External radii are
rigid and the anterior clasper bears 8 serrations in a line. The pelvic girdle consists of right
and left cartilages. Sexual maturity in males can be considered to be reached at a body
length of 45 to 50cm.
There
the
are
many
different
fields
few
of them
even
fewer
has
research
larger,
their
of study
refer
on
Only
characters.
new
histological,
extended
to
important
Holocephali
in marine
ecology,
histology,
sources,
etc.
It is the
and
has
morphology
eco-
been
is equally
fishery
organs
of the
to the enhancement
authors
of the
re-
to conrange
primitive
out research
and ecology,
on the
and on the male
of
one
Holocephali
species, namely Chimaera phantasma.
The morphological
and ecological
ters of other Holocephali
countries
have
been
collected
described;
characin other
Harriotta
raleighana by GARRICK(1971, 1975), Chimaera
monstrosa, C. colliei, C. mirabilis, and Callo-
1922b), Neoharriota
(1966), Harriotta
purpose
seemingly
rhynchus antarcticus by LEIGH-SHARPE(1922a ,
classification,
undeveloped
of these
by carrying
reproductive
recent
not
which
animal
and
about
this
in Elasmobranches
animals
become
knowledge
However,
but
recently
Elasmobranches
morphological,
interest
of fishes,
to Holocephali.
information
concerning
to Elasmobranches
providing
logical
tribute
publications
of
carrii
by BULLIS et al
raleighana
hamphus by BEAN et al (1910),
callorhynchus and Harriotta
and H. chaetirCallorhynchus
curtis-jamesi by
*1. A part of this study was supported by scientific research fund from the Ministry of Education.
*2. Ocean Research Institute, University of Tokyo, Nakano, Tokyo, Japan.
12
G． Malagrino and A． Takemura and K． Mizue ： Studies on Holocephali−1
BEEBE et al （1941）．
species could be caught every month in
As for the Holocephali species in Japa−
the same waters． At the sarne time， it
nese coastal waters， brief morphological
seems that the number of C． phantasma
and ecological studies have been made on
landed at the fish market depends on the
Chimaera phantasma， C． （Phasmichtys） mitsu−
state of commercial fishery． This species
kurii， and Rhinochimaera pacifica by DEAN
does not appear to be so important econom−
（1904a， 1904b）， and on Holocephali in gen−
ically； it is caught only accidentally by
eral by TANAKA （1905）．
the fishermen whose real aim is to catch
According to MATsuBARA （1955）， only
sea bream and other expensive fishes． C．
nine species of Holocephali are known to
phantasma is utilized in the same way as
be in Japanese coastal waters． Among
sharks． lt is eaten mainly as boiled fish
them， two species， Chimaera phantasma and
paste or parboiled．
Phasmichtys mitsukurii， are frequently found
In the present paper， the specimens were
while the others are rarely caught．
collected and examined in order to inves−
At the Nagasaki Fish Market， Chimae−
tigate their morphological and reproductive
roids are seldom landed except for C． phan−
characters， and to compare them with
tasma， which can be collected throughout
those of other Holocephali already descrided
the year together with the subdeep sea
and of Elasmobranches．
shark， Heptranchias perlo． Nevertheless， the
Materials and Methods
number of specimens is usually not large，
specially during the winter season and
August． According to our own catches，
Many individuals of C phantasma （Fig． 1）
approximately the same number of this
are landed at the Nagasaki Fish Market
Fig． 1． Chimaera phantasma
together with Heptranchias perlo throughout
saki Fish Market or by the authors them−
the year， especially from April to July and
selves in coastal waters off Nagasaki
from September to October． The amount
Prefecture from September 1975 to October
varies according to the fishing activities
1976． According to the fishermen， C． phan−
which decrease during August and are
tasma is caught in waters 200−300m deep，
switched to different fishing grounds in
along the continental shelf of the East
winter．
China Sea． The fishing ground is shown
Materials were collected either at Naga一
by the dark area in Fig． 2．
13
Bull． Fac． Fish． Nagasaki UniV．， No． 42 （1977）
130eE
1250E
Number of specimens of C．
。
phantasma in each month
ノ Kyyshu
0ct．
ノリ
Nov．
Dec．
Jan．’76
Feb．
・愈．．．
30eN
Fishing
Mar．
Apr．
ground
May．
麟難轡
Jun．
側＿、
Jul．
Aug．
D
Sep．
Oct．
．，．．．，．1““g“
謡，、。、
ゴ
Total
191
115
Tota1
4
1
0
5
0
448639949
0
143ワ飼39側
Sep．’75
．●●齢、
外
Male
QJームー 雪⊥−⊥
Xtw’ “・…1 00f
Female
1
1
152421
0
4
0
7・2
220
298
臼−←
しなニもサロロ ロサくココ ぴ㌣ムv
Month
30010240587528
嬬tW
く、講欝欝
鰭 ． 、 県
〈 i＞
Table 1．
306
the posterior base margin・bf the anal fin
250
b
m
（Fig． 3， No． 14）．
Results and Discussions
Fig． 2． Fishing ground
The authors’ operations were carried out
on the research boat ““Kakusui”， of Naga−
saki University， in the same area at depths
1．・ Growth
Proportional dimensions of 30 parameters
were measured， as shown in Fig． 3． Table 2
8
ranging from 100m to 600m （Fig． 2−B）．
7
6
Angling by means of bottom long line or
5
4
3b
vertical long line was generally’used，
2 や
1
because this species lives at depths greater
than the usual fishing grounds of commer−
⊃
1
found in gill nets of fishermen． Table 1
’
⇔
噛 一 ’
●
’
2
−1
9皿
cial bull trawling． This species is rarely
13
14
in each month． The specimens were meas−
謬藺
shows the number of specimens collected
ured and dissected in the laboratory． Mor−
phological characters were investigated， and
ta ik2E｝×＝
x rnxF｛11 ￠
12，’，
20：ヨ1
reproductive organs， content of digestive
Ls T，
organ， liver， dorsal spine and teeth were
taken out for examination． Since the long
iz27一
and flexible tail was often found broken，
the body length is given in terms of the
length between the tip of the snout and
Fig． 3．
猶
Proportions of external measurements
14
1．
3B．
4．
5．，
〃〃〃〃〃〃
〃〃〃〃〃〃
3A．
〃〃〃〃〃〃
From snout tip to anterior margin of eye；
posterior margin of eye；
〃〃〃〃〃〃
2．
G． Malagrino and A． Takemura and K． Mizue ： Studies on Holocephali−1
rils；
18．
’origin of first dorsal fin；
6．
19．
origin of secon，d dorsal fin；
20．
base of second dorsal fin
コ コ
〃〃
〃〃
〃〃
〃〃
コ 9臼9臼9︼
245
コ 1／ 11 ／／ 1／ anterior margin of anus；
〃 ‘ ‘．．〃 〃 〃 origi血．．of posterior claspef；
ii ii ii ii diverging point．of poste−
rior clasper；
post号rior margin of pecto−
〃〃〃
〃〃〃
〃〃〃
の コ コ つ
234567
26．
ral fin；
〃〃〃
7
8QVO噌⊥
■⊥可⊥
1←i⊥−←1ーユー⊥
base of pectoral fln end；
ll 11 ／1 11 posterior margin of po＄te−
rior clasPer；
origin of pelvic fin；
base of pelvic fin end；
27．
base of anal fin end；
！1 1／ 11 11 anterior margin of gono−
pore；
28．
Length of dorsal spinel
，
29．
From snout tip to anterior margin of nostrils；
り
Table 2．
11 11 ll ll anterior margin of anterior
clasper；
Total length；
From snout tip to origin of pectoral fin；
posterior margin．
ii ii ／i ii anterior margin of gill
opentng；
21．
origin of upper caudal fin；
ll ／／ ll ll
ii ii i／ ii posterior margin of labium
mandibulare；
base of first dorsal fin end；
end；
！／ ！1 ／1 11
ii ii ii ii anterior margin of labium
mandibulare；
tip of frontal clasper；
30．・
盾?@nost一
Width of pouch of anterior c14sper；，
Length of frontal clasper；
Tip of snout to base of caudal fin end；
Proportional measurements of C． phantasma at intervals
of 10cm body length
proportional dimentions in percent of body length （No． 14）
No．
female （cm）
male （cm）
O−49
コ コ ロ コ コ の ロ ロ コ コ コ サ の ロ ロ ロ コ コ サ コ の
1⊥ −⊥
1⊥
B 。 ． 9 ・ 。 ● ●．。 ・ ・ 。 ・ ふ ・ ． ． 9 ● ● ・ ・ ． 幽
■⊥
サ コ コ コ コ の ロ サ ロ リ ロ サ ロ コ ロ ロ コ コ ．−⊥ 446
12蹟認翻翻3910n1213皿拓1617181920212
76
26
02
30
57
792
76
53
17
59
806
97
07
6
0
11 24
926
225
44
010
12
9801367
12
680
10
0
6
6
3
4
8
78
86
22
00
93
74
．8
1
1
2
4
i
⊥ 9
4
2244501 11
36
76
83
508
4
6
41
9
1
09
8
3
1
92
2
90
3
62
7
11 242
99
5．
28
57
45
10
9
1
2
O−49 50−59 60−69
2．0
2．8
2．5
1．8
3．0
2．7
118．0
104．7
50−59 60−69
70−79
80−89
10．0
10．7
10．6
10．7
11．9
15．7
14．3
15．9
15．9
16．7
22．0
22．1
22．4
22．1
25．6
41．3
41．2
40．4
41．2
42．3
99．6
100．0
99．8
98．5
99．7
159．9・
138．4
143．8
135．1
125．1
25．6
23．0
23．8
23．0
23．6
26．6
27．0
27．2
27．2
28．2
55．5
55．5
53．9
53．7
55．0
47．9
49．2
49．8
49．1
50．4
60．4
52．4
53．1
51．5
53．2
100．0
100．O
100．0
100．0
100．0
22．8
I9．2
17．9
16．4
15．8
7．8
7．6
7．1
7．6
7．7
9．1
8．8
7．9
7．8
8．4
11．2
10．4
9．8
9．9
10．4
13．1
12．6
11，7
11．8
12．7
23．7
20．9
20．6
20．3
21．3
55．9
49．4
49．7
49．2
50．0
51．5
51．9
52．6
51．8
52．7
58．0
51．4
54．2
53．0
52．9
115．7
105．2
111．2
Bull． Fac． Fish． Nagasaki Univ．， No． 42 （1977）
15
shows the ratio between proportion measu−
seasonal variation can be observed， the
rements and body length expressed in
value being larger in summer and smaller
percentage for individuals grouped at in−
in winter． However， the variation of the
tervals of 10cm．
condition factor with the season is smaller
As for the number of specimens observed，
than that with the body length． ln the
5 females were of the body length less
female， this factor remains almost constant
than 50cm， 54 in the range of 60−70cm， 77
for both season and body length．
in the range of 70 to 80cm， and 36 in the
In both sexes， the hepatosomatic index
range of 80 to 90cm． ln the male， 1 was
× 100 shows no difference
less than 50cm， 62 in the range of 50 to
60cm， and 48 in the range of 60 to 70コ口，
Data on specimens of both sexes less
than 50cm in body length is scarce and
therefore， for information， not valid， how−
ever this data is indicated only because all
of these specimens were found to be still
inmature．
liver weight
body weight
by body length or season．
2． Teeth
In Elasmobranches teeth are usually
present in large number in both jaws，
with the characteristic of being renewable，
and they play an important role in their
classification．
The tail and the dorsal spine were often
found broken so data on both shows some
discrepancies among individuals of similar
body length．
It may be observed from Table 2 that
the increment of body length in males is
accompanied by a proportional increment
of pelvic and anal fin， while the thorax
and trunk region proportion remains almost
unchanged． The head， by contrast， shows
a slight decrease．
In the case of females less marked
changes in the proportions are observed
for each region．
The relation between body length （L cm）
and body weight （W gr） is indicated by
the following formulas．
Male ：W ＝ O．1913L2・2269
Female：W ＝ O．0376L2・6349
Fig． 4． Teeth， A： Frontal view of tooth，
B： Ridges of vomerine plate， C：
Three pairs of dental plate
1n the male． the condition factor
’
謡織審×…sh・w・at・nd・n・y・f
The teeth of Holocephali （Fig． 4） are
entirely different， being larger in size and
decreasing with the increase of body length；
not numerous but equally sharp and strong，
it is about 9 for individuals of 50cm in
with knobs and ridges embedded in them．
body length， and it decreases to about 7
The function of the teeth of C． phantasma
for individuals of 70cm． Moreover， a small
is quite similar to that of globefish， well
16 G． Malagrino and A． Takemura and K． Mizue ： Studies on Holocephali−1
adapted to crush strong bodies like crusta−
age， but so far they seem to have failed
ceans or bivalves． Because of this strength，
to serve the purpose．
we somel．t／． rne＄，，．．，，．found the n，ylon gut．of p， ur
bottom long line cut and we had to use
5．’ Content of digestive organ
wire as gut．
The content of the spiral intestine was
As described by TANAKA （1905）， they
’ examined in 101 males and 171 females．
consist of three pairs of dental plates： the
’vomerine plates and palatine plates in the
［H目］♂
75
upper jaw and the lower plates in the
lower jaw． These plates are thick at the
base and thin ’at the top， specially the
Φo⊆o﹂8αξ↑O台5コ9﹂L
vomerine and lower pairs， and are support−
ed by cartilage． With the mouth closed，
the lower plates fit ’the gap between
vomerine and palatine plates． As a conse−
O
25
quence of repeated bitings， the tip of the
inner surface of those plates is defaced．
On the inner Surface of each vomeripe
plat’
?@there are ridges as shown in Fig．
4−B， whose number is ustially the same for
謂 ’” ．ω 誘’
葦1ξll∼ll舘．1．董一：
both Plates．
Fig． 6． Frequency of appearance of intestinal
content of C． phantasma “’
20
ｳ0で一匡￡↑①oト
り。
The frequency of appearance of intestinal，
content by kind is shown in Fig． 6． The
む
0
t“
‘ 宅
O o o
o
o ｛P o
o
oarasite” is Gyrocotyle sp． Sometimes four，
or five individuals can be found−in one
specimen of C phantasma． lncluded in
tt
nthers” are occasional’remains of squidpi
starfish， seaweeds， and sea anemones． lt
500 600 700mm
Body Length （No．14）
Fig． 5． Relationship between body length
and teeth ridges
was difficult to define the species because
the content almost always was found in an
advanced stage of digestion．
From Fig． 6 it is clear that C． phantasma
It seems that these layers could be
of both sexes feeds mainly on crustaceans，
related to growth （Fig． s＞ but not to age．
specially crabs with a carapace ． length of
At the same time， the above mentioned
about 3−4cm． Other kinds of conterit were
defacement prevented us from． a reliable
also of similar size． They were mostly
counting of ridges． Other body dimentions
bentie animals， like crabs， shrimps， amphi−
like skeleton length， number of dorsal
pods， shellfish， starfish， sea anemons， with
spine・serrations， and eyeball diameter were
no or rather limited swimming ability． This
examined to look for a clue to determining
fact strongly suggests that C． phantasma
17
Bull． Fac． Fish． Nagasaki Univ．， No． 42 （1977）
mainly lives at the Sea bottom． According ln general it can be said
that though
to DEAN （1904a）， movements are sluggish Holocephali have far less
species than
when kept in shallow water． But the
AnteTior Clasper
presence of small−fish bone indicates C．
phantasma could actively swim in his
natural habitat in search of food・ ko ？ K O一〉
Pelyie Girdle
4． External clasper
e
Metapterygium
bb
o
。お
ｫ
n。l sexu。1。，g。n。 a p。i，。f。h。，act・，i、ti・ ぷ‘
claspers． Holocephali have， in addition to 8
Join重 Car重ilage
this， a pair of anterior claspers and a
Be重aC．
O
Males of Elasmobranches have as exter−
Propterygium
“rscys．Nss“N．5
Ra’ р奄≠P C．
frontal clasper （Fig．7）．
The posterior clasper （Fig．8） quite
Stern C．
resembles externally that of Elasmobran。
ches， and so are its skeleton and the ske1−
eton of pelvic fin． As described on Chimaera
spP．，（）allor：ynchus sp． and Harriotta sp． by
GARRIcK（1971，1975）， DEAN（1904a，1904b）
and LEIGH−sHARpE（1921，1922），many differ−
ences can be accounted between the clasper
Fig． 9． Right skeleton of pelvic fin and
posterior clasper， Right： ventral
of Holocephali and that of Elasmobranches．
view， Left： dorsal view
Elasmobranches， they present a great−
er variety in the morphology of
their clasper．
The clasper of Elasmobranches is
not divided but in some species of
Holocephali it is divided into two or
three． ln C． phantasma， the posterior
clasper bifurcates into external and
internal radii． The external radius
’
Fig． 7． Frontal clasper
in its turn， bifurcates into two （Fig．
9）． Unlike k−those of C． monstrosa，
described by LEiGH−sHARpE （1922a），
radii of C． phantasma are not flexible．
The tips of these radii have no
dermal hooklets or accessory organs
as Elasmobranches do．
The dorsal basement of each poste−
rior clasper is covered by muscle
and is fleshy． Near each base there
Fig． 8． Posterior clasper， Right： ventral view，
is a small pouch． On C． monstrosa，
Left： posterior view
LEiGH−sHARpE （1922a） describes a
18 G． Malagrino and A． Takemura and K． Mizue ： Studies on Holocephali−1
clasper cavity in this dorsal swelling that
at the basement region， each radius looking
opens at the diverging poirit of the poste−
like a scroll． The radial cartilage of this
rior clasper． No’
@presence of clasper cavity
species is formed by 15．cartilages．
can be found in C． phantasma．
The tip of the outer border of the ante−
6． Relationship of body length with teste’s
rior part of the clasper is covered by loose
weight and with clasper length
and denticled skin． Many capillary vessels
Almost all 115 males， collected at the
are present in this body．
Nagasaki Fish Market and caught by our−
The anterior clasper of C． phantasma has
selves， were more than 50cm in body
no conspicuous differences from other
length， with the exception of one individual
Chimeroids． They bear 8 spines in line on
measuring 44．3cm caught in June．
its inner border． The pouches are widely，
The smallest specimen in the range of
open in a transverse axis with the body．
50 to 60cm， had a body length of 51．4cm，
The frontal clasper nearly resembles that
the differnce between these two individuals
of other Holocephali and is usually kept
being not so large． HoWever a striking
in a small depression of the skin as shown
difference can be appreciated in clasper
in Fig． 7． lt is strongly denticled on its
length． We considered as clasper length of
inferior surface， as described by LEiGH−
the outer clasper only．
sHARpE in C． monstrosa and Callorhynchus
轡
antarctzcus．
e
評凶
O
呪競
錦押
O
。。轟
0
O 8
between Holocephali and Elasmobranches．
The skeleton of the pelvic fin and clasper
εO⊆の﹂﹂oαω06
general structure of pelvic fin and clasper
O殖 5
There are not so many differences in
Om O
5． Skeleton of Pelvic Fin and Clasper
e
O
O
O
O
o
o
’consists of pelvic girdle， propterygium，
metapterygium， radial cartilages， joint carti−
lage， beta cartilage and stem cartilage
（Fig． 9）．
500 600 700mm
Body Length（No．14）
Fig． 10． Relationship between body length
and posterior clasper length
The pelvic girdle is connected to the
While the clasper length in the smallest
anterior clasper at its anterior margin by’
specimen is 1．7cm， it is around the average
a ligament． The biggest difference from
（9．5cm） for all other specimens （Fig． 10）．
Elasmobranches is found in the pelvic
On the other hand， the difference be−
girdle which consists of left and right
tween the testes weight of the small indi−
cartilages in C． phantasma but only one
vidual and that of specimens in the range
cartilage in most sharks． A complex system
of 50 to 60， is not so remarkable as the one
of small bones is at the tip of the stem
observed in clasper length （Fig． 11）． Nev−
cartilage in many kinds of sharks； there is
ertheless， it can be easily appreciated that，
none in C phantasnza． LEiGH−sHARp （1922）
though in large individuals increment of
described dermal hooklets at the tip of the
testes weight with body length is slow， it
stem cartilage of Rhinochimaerd atlantica．
does increase rapidly from the small indi−
Moreover， stem cartilage ，is trifurcated
vidual to the small ones in the large group．
Bull. Fac. Fish. Nagasaki Univ., No. 42 (1977)
Smithosonian
2.
19
Institution,
37, 661-663.
BEEBE, W., and TEE-VAN, J. (1941). Zoologica,
Scientific
Contribution
of
the
New
York
Zoological Society, 26(3), 245-280.
3.
BULLIS,H. R. JR., and CARPENTER,
J. S. (1966)
Copeia, 3 443-450.
4.
DEAN, B. (1904a). J. Coll. Sci., Imp. Univ.
Tokyo, 19 (3), 1-9.
5.
DEAN, B. (1904b). J. Coll. Sci. Imp. Univ.
Tokyo, 19 (4) 1-20.
6.
Fig.
11.
Relationship
and
From
from
the
the
between
testes
all
caught
in
July
weight,
we
can
contrast
in
ingly,
we
phantasma
body
the
results,
other
had
observe
conspicuous
Accord-
can
fairly
consider
that
45 and
maturity
LEIGH-SHARPE,
W. H. (1922a). J Morph., 36,
199-220.
221-240.
C.
at
of
Research, 9, 159-167.
10. LEIGH-SHARPE,W. H. (1922b). J Morph., 36,
maturity.
sexual
9.
testis
sexual
between
of the Royal
GARRICK,J. A. F. (1975) N. Z. Journal
Marine and Freshwater
18 speci-
bigger
a
8.
and
the
reaches
length
31 (3), 35-40.
GARRICK,J. A. F. (1971) Journal
7.
Society of N. Z. 1, 203-213.
mentioned
that
mens
length
weight
above
fact
body
DEAN, B. (1912). Bull. Amer. Mus. Nat. Hist.,
11. MATSUBARA,
K. (1955). Fish Morphology
a
Hierarchy.
50cm.
and
Ishizaki shoten, Tokyo, 143-145.
12. OHTA N. (ed). (1974). World Animal Encyclopedia, 159, Asahi Shimbun,
Tokyo, 4.
13. TANAKA, S. (1905), dobutsugaku
References
zasshi,
17
(206), 353-369. (In japanese).
14. TANAKA,S., TESHIMA, K., and MIZUE, K.
1. BEAN, A. B., and WEED, A. C. (1910).
Proceeding of the U. S. National Museum,
(1975), This Bull., 40, 15-22.
全 頭類 の研究―I
ギ ン ザ メ Chimaera
phantasma
の 形 態 と雄 の生 殖 器 官 に つ い て
ジ ォ バ ニ ・マ ラ グ リ ー ノ ・竹 村暘
1975年9月
体(雄115個
・水 江 一 弘
か ら1976年10月 に か け て長 崎 魚 市 に水揚 げ され た り,著 者 らが長 崎県 沿 岸 で 採 捕 した ギ ンザ メ306個
体,雌191個
体)に つ い て,形 態 学 的 に,雄 につ い はは 生殖 生態 につ いて も調 査 した。 成 長 に伴 う各
部 の外 形 プ ロポ ー シ ョンの 割 合 は ほ ぼ一 様 で あ る。 また,雌 雄 の成 長 式 は 次 式 で示 され た。
雄:W(g)=0.1913L(cm)2.2269
雌:W(g)=0.0376L(cm)2.6349
雄 の肥 満 度 は成 長 に伴 い 減 少 す るの が観 察 され た。 歯 は非 常 に強 固 な三 対 の歯 板 よ りな り,主 と し て底 棲 動 物 を
捕 食 し,中 で も小 型 の カニ を 最 も多 く捕 食 して い る。 Posterior
external
radii
は屈 曲 しな い。 Anterior
clasper
二 つ に 分 離 し て い る。 本 種 の 雄 は 体 長(No.14)45cmか
clasper
は三 叉 し,先 端 は 顕 著 な 附属 物 は な く,
の 内縁 に は 一 列 に並 ん だ8個 の 棘 が あ り, Pelvie
ら50cmで
成 熟 に達 す る。
girdle
は左右