Revision of the family Acidopsidae Števčić, 2005, and the systematic position of Typhlocarcinodes Alcock, 1900, Caecopilumnus Borradaile, 1902, and Raoulia Ng, 1987, with descriptions of two new genera and five new species (Crustacea: Brachyura: Goneplacoidea)
Author
Ng, Peter K. L.
dbsngkl@nus.edu.sg
Author
Rahayu, Dwi Listyo
dbsngkl@nus.edu.sg
text
Zootaxa
2014
2014-03-03
3773
1
1
63
journal article
5890
10.11646/zootaxa.3773.1.1
6da85b06-8386-41bc-9b34-b16eba941eab
1175-5326
4909796
19F28753-B2D0-4D1F-9D47-88886F7333FD
Subfamily
Acidopsinae
Števčić, 2005
Acidopidae [
sic
]
Števčić, 2005: 36
.
Parapilumnidae
Števčić, 2005: 70
.
Diagnosis
. Eye mobile, not pear-shaped, cornea as wide as or wider than peduncle with cornea round, pigmented; or elongated, with distal part gently tapering, cornea small but pigmented; basal antennal article quadrate, as wide as long (
Figs. 6A, B
,
11D
); epistome level, not sunken (
Fig. 12A
); anterolateral angle of third maxilliped merus angular (
Figs. 5A, B
,
10C
,
11E
); lateral edge of a3 between cx4, 5; lateral edge of a2 adjacent to cx5, st8 barely visible when abdomen closed (
Figs. 1A–D
); male opening coxal, penis short; male abdomen completely protects penis when closed; only small part of st8 visible when abdomen closed; female sterno-abdominal cavity deep, transversely narrow, vulvae positioned close to median longitudinal groove of st6 (
Figs. 3
,
10D
).
Material examined
.
Acidops fimbriatus
Stimpson, 1871
:
1
female (19.7 ×
14.9 mm
) (MNHN-IU-2013- 9470), station 8, bottom of coral reef, brushing,
10°18.49’N
109°14.1’W
, Clipperton I., Expedition
CLIPPERTON
, coll. J. M. Bouchard et al.,
14 January 2005
;
1 female
(19.2 ×
14.6 mm
) (
USNM
1191707) [photographs examined], Angel de la Guardia I., 10–15 fms (
20–31 m
), Puerto Refugio, Mexico, coll. F. E. Lewis,
14 April 1939
.
Acidops cessacii
(A.
Milne-Edwards, 1878
)
:
1 male
(7.7 ×
5.9 mm
),
1 female
(14.1 × 10.0 mm) (
NHM
99.3.23.66–67) (
syntypes
of
Epimelus cessacii
A.
Milne-Edwards, 1878
), Cape Verde Is.,
10–30 m
;
1 male
(11.3 ×
8.1 mm
),
1 female
(12.6 ×
9.9 mm
) (
ZRC
1998.58), beach and tide pools on rocky point west of main beach, North East Bay, Ascension, coll. R.B. Manning
19 May 1971
; 1 ovigerous female (9.7 ×
7.3 mm
) (
ZRC
2013.1459), rocky shores, under large rocks,
0.5–1 m
, near Pato Alegre, São Tomé, coll. A. Anker,
5 February 2006
.
Parapilumnus cristimanus
(A. Milne-Edwards, 1873)
:
lectotype
female (16.5 × 13.0 mm) (
MNHN-B
12938), Upolu, Samoa, coll. M. Balansa;
paralectotype
female (14.5 ×
10.9 mm
) (
MNHN-B
12939), New Caledonia, coll. M. Balansa;
1 male
(10.2 ×
7.6 mm
) (
IOCAS
SSFVI2-2),
1 male
(16.3 ×
12.5 mm
) (
ZRC
2003.90), Nansha Is. (Spratly Is.), South China Sea, coll.
9 May 1989
;
1 female
(23.2 ×
17.7 mm
) (
ZRC
2013.1905, ex
MNHN
2013- 268), station PR 10, outer slope,
22 m
, Paeowa I.,
05°10.8'S
145°49.8'E
, Papua New Guinea, coll. Expedition PAPUA NUIGINI,
8 November 2012
;
1 female
(10.1 × 8.0 mm) (
MNHN
2013-513), station PR 48, Malamal Passage, Sek I.,
5°07.2'S
145°49.4'E
, Papua New Guinea, coll. Expedition PAPUA NUIGINI,
17 November 2012
.
Parapilumnus oryctus
Ng, 2002
:
Holotype
male (12.3 ×
10.5 mm
) (
ZRC
2002.174), Luminao fore reef, in rubble,
20–25 m
, Guam, coll. H.T. Conley,
May 1998
.
Remarks
. The history of the family has already been discussed at length earlier. The genera
Acidops
Stimpson, 1871
, and
Parapilumnus
Kossmann, 1877
, are relatively well studied (see
Monod 1956
;
Guinot & Ribeiro 1962
;
Manning & Holthuis 1981
;
Ng 2002
;
Ng & Chen 2004
;
Guinot
et al.
2013
).
Epimelus cessacii
A.
Milne-Edwards, 1878
, was described as the
type
species of
Epimelus
A.
Milne-Edwards, 1878
, based on material from
Cape Verde
Is.
Monod (1956: 358–359)
discussed the status of
Epimelus
and argued it was a junior subjective synonym of
Acidops
, noting that at his request, John Garth compared the two respective
type
species and no major differences could be found to warrant two genera.
Rathbun (1930: 533
, pl. 215) reported that material from
Australia
also belongs to
A. fimbriatus
.
Garth (1946: 475)
figured a male specimen of
A. fimbriatus
from the Galápagos Is. and argued that Rathbun’s Australian material did not belong to this species. We agree that
Rathbun’s (1930
: pl. 215) figure of her South Australian specimen closely resembles a species of
Heteropilumnus
De Man, 1895 (Pilumnidae)
instead, and is clearly not a species of
Acidops
. Our comparisons show no major characters separating them, and we agree with
Monod (1956)
that
Acidops fimbriatus
Stimpson, 1871
, and
Epimelus cessacii
A. Milne- Edwards, 1878, are congeneric but are different species.
Acidops fimbriatus
and
A. cessacii
are indeed very similar (
Fig. 7A–D
). Comparisons of the female specimens of both species on hand show only minor differences: the basal antennular article of
A. fimbriatus
is relatively wider and larger, the front is proportionately more produced and the anteroexternal margin of the third maxilliped is relatively less angular and more rounded. Their colours in life also seem to differ, with
A. fimbriatus
a relatively uniform yellowish-brown on all its dorsal surfaces (
Fig. 40A
) while
A. cessacii
is dirty white with small patches of maroon (
Fig. 40B
). It is possible there will be more differences that when the male abdomen and gonopods of
A. fimbriatus
can be described and figured. For the moment, in view of the different distributions (one Pacific and the other Atlantic) and the differences observed above, it is best to recognise both species as valid.
The specimens of
Acidops cessacii
examined (including
two syntypes
) show some variation. The anterolateral margins show three low granuliform teeth (excluding the external orbital tooth), separated by low notches, accentuated by a short, shallow groove on the carapace. The grooves can be rather indistinct in some specimens and/or depending on the angle from which the carapace is viewed, giving the appearance that the carapaces look different (
Fig. 7A, C, D
and
Fig. 7B
) (see also A.
Milne-Edwards & Bouvier 1900
: pl. 15 figs. 1–8).
Acidops fimbriatus
occurs in the eastern Pacific, from California,
Mexico
to
Clipperton
I. and the Galápagos (
Garth 1946
;
Hendrickx 1995
;
Poupin
et al.
2009
).
Acidops cessacii
has a wide distribution in the Atlantic, occurring from West Africa to
Brazil
(see
Monod 1956
;
Manning & Holthuis 1981
;
Barreto
et al.
1993
;
Melo 1996
).
With regards to
Parapilumnus
, the additional specimens of
P. cristimanus
from
Papua New Guinea
partially fill in a geographical gap; the species was previously only known from
New Caledonia
and the South
China
Sea. They agree well with the redescriptions and figures of the species by
Ng (2002)
and
Ng & Chen (2004)
. Comparisons of all the material of the two species on hand indicate that the differences in the carapace granulation, form of the ambulatory legs and chelae cited by
Ng (2002)
to separate
P. cristimanus
from
P. oryctos
(known only from
Guam
) are not reliable and vary too much to be useful (see also
Ng & Chen 2004
). The carapace proportions remain useful, with that of
P. oryctos
still the most rounded (width to length ratio of 1.2,
Fig. 8C
) while all
P. cristimanus
, including the recent material, have ratios of 1.3 (
Fig. 8A
). In addition, there are also marked differences in the form of the male abdomen and G1 structures of the two species (see
Ng & Chen 2004
).
FIGURE 4
. Female thoracic sterna, abdomens and vulvae. A, B,
Raoulia piroculata
(
Rathbun, 1911
)
, lectotype female (7.3 × 5.5 mm) (USNM 41359a), Amirante Is., Indian Ocean; C, D,
Caecopilumnus crassipes
(
Tesch, 1918
)
, female (13.0 × 11.0 mm) (MZB), Lombok, Indonesia; E, F,
Thecaplax capillosa
gen. et. sp. nov.
, paratype female (12.7 × 10.5 mm) (ZRC 2013.1714), Lombok, Indonesia; G, H,
Typhlocarcinodes integrifrons
(
Miers, 1881
)
, paralectotype female (7.0 × 5.4 mm) (NHM 81.24b), Goree I., Senegal.
FIGURE 5
. Right third maxillipeds. A,
Acidops cessacii
(A.
Milne-Edwards, 1878
)
, syntype female (14.1 × 10.0 mm) (NHM 99.3.23.66) Cape Verde (laterally inverted); B,
Parapilumnus cristimanus
(A. Milne-Edwards, 1873)
, male (16.3 × 12.5 mm) (ZRC 2003.90), Nansha Is. (Spratly Is.), South China Sea (laterally inverted); C,
Raoulia limosa
Ng, 1987
, holotype male (8.3 × 6.3 mm) (ZMUC M58), off Marongas, Jolo, Philippines; D,
Raoulia piroculata
(
Rathbun, 1911
)
, lectotype female (7.3 × 5.5 mm) (USNM 41359a), Amirante Is., Indian Ocean; E,
Raoulia galea
sp. nov.
, holotype male (9.4 × 7.4 mm) (ZRC 2000.0980), Phuket, Thailand; F,
Raoulia fortis
sp. nov.
, holotype male (12.0 × 9.2 mm) (MNHN), Santo, Vanuatu (laterally inverted); G,
Raoulia calva
sp. nov.
, holotype male (6.6 × 5.2 mm) (ZRC 2013.1721), Society Is., French Polynesia; H,
Caecopilumnus hirsutus
(
Borradaile, 1902
)
, male (7.1 × 5.6 mm) (ZMA 261027), Flores, Indonesia (laterally inverted); I,
Caecopilumnus crassipes
(
Tesch, 1918
)
, male (11.8 × 10.1 mm) (ZRC 2013.1710) Lombok, Indonesia; J,
Caecopilumnus loculatus
sp. nov.
, holotype male (8.0 × 6.7 mm) (ZRC 2013.1723), Moorea, French Polynesia (laterally inverted); K,
Thecaplax capillosa
gen. et. sp. nov.
, holotype male (11.6 × 9.5 mm) (MZB), Lombok, Indonesia; L,
Typhlocarcinodes integrifrons
(
Miers, 1881
)
, lectotype male (8.5 × 6.9 mm) (NHM 81.24a), Goree I., Senegal.
FIGURE 6
. Left antennae and antennules. A,
Acidops cessacii
(A.
Milne-Edwards, 1878
)
, male (11.3 × 8.1 mm) (ZRC 1998.58), Ascension; B,
Parapilumnus cristimanus
(A. Milne-Edwards, 1873)
, male (16.3 × 12.5 mm) (ZRC 2003.90), Nansha Is. (Spratly Is.), South China Sea; C,
Raoulia fortis
sp. nov.
, holotype male (12.0 × 9.2 mm) (MNHN), Santo, Vanuatu; D,
Caecopilumnus crassipes
(
Tesch, 1918
)
, male (12.9 × 11.4 mm) (ZRC 2013.1711), Lombok, Indonesia; E,
Thecaplax capillosa
gen. et sp. nov.
, paratype male (13.2 × 10.7 mm) (MZB), Lombok, Indonesia; F,
Typhlocarcinodes integrifrons
(
Miers, 1881
)
, lectotype male (8.5 × 6.9 mm) (NHM 81.24a), Goree I., Senegal. Abbreviations: at3 and at4 = basal antennal articles 3 and 4, respectively; bs = basal antennal article; ba = basal antennular article. Scales = 0.5 mm.
FIGURE 7
. A,
Acidops fimbriatus
(
Stimpson, 1871
)
, female (19.7 × 14.9 mm) (MNHN-IU-2013-9470), Clipperton I.; B-G,
Acidops cessacii
(A.
Milne-Edwards, 1878
)
. B, syntype female (14.1 × 10.0 mm) (NHM 99.3.23.66), Cape Verde; C, G, female (12.6 × 9.9 mm) (ZRC 1998.58), Ascension; D, E, male (11.3 × 8.1 mm) (ZRC 1998.58), Ascension. A–D, overall dorsal views; E, anterior thoracic sternum and male abdomen; F, right chela; G, left chela. C by A. Anker.
Interestingly, both species have similar colour patterns, with the dorsal surface of the carapace dirty white with regularly arranged patches and spots of red or orange; and the legs have bands and patches of red and orange (
Fig. 40C, D
). In this respect,
Parapilumnus
is similar to
Crinitocinus
gen. nov.
(
Fig. 40E–H
).