RAFFLES BULLETIN OF ZOOLOGY 2014
RAFFLES BULLETIN OF ZOOLOGY Supplement No. 30: 255–262

Date of publication: 25 December 2014
http://zoobank.org/urn:lsid:zoobank.org:pub:A6CFEB01-E342-4F91-92C0-97C6EA3C94CC

Porcellanidae (Crustacea: Decapoda: Anomura) from Christmas andCocos (Keeling) Islands
Masayuki Osawa
Abstract. Eight porcellanid species are reported from Christmas Island and the Cocos (Keeling) Islands in thesoutheastern Indian Ocean, based on specimens collected by three expeditions to the islands from 2010 to 2012. Of
them, five species are new local records: Petrolisthes asiaticus (Leach, 1820), P. bispinosus Borradaile, 1900, P.
fimbriatus Borradaile, 1898, P. pubescens Stimpson, 1858, and P. scabriculus (Dana, 1852). Petrolisthes bispinosus
and P. fimbriatus are reported for the first time from the Indian Ocean.
Key words. Crustacea, Decapoda, Porcellanidae, eastern Indian Ocean, new records

INTRODUCTION

This paper reports on porcellanids collected by three
expeditions to Christmas and Cocos (Keeling) Islands from2010 to 2012, carried out by staff of the Lee Kong Chian
Natural History Museum (formerly Raffles Museum of
Biodiversity Research), National University of Singapore,supported by staff of the Parks Australia and the Queensland
Museum. The collection is small, but includes five species
that represent new records from those islands.

The family Porcellanidae is a group of crab-shaped anomuran
crustaceans and belongs to the superfamily Galatheoidea
together with other three familes, Galatheidae, Munididae,
and Munidopsidae (Ahyong et al., 2010). The porcellanids
are commonly found in rocky and coral reefs of temperate
and tropical coasts. The best known genus is probably
Petrolisthes Stimpson, 1858, which is the most species-richin the family with 107 species currently recognised (Osawa& McLaughlin, 2010; Osawa & Uyeno, 2013; Naderloo &Apel, 2014).

The material examined is deposited in the Zoological
Reference Collection (ZRC) of the Lee Kong Chian Natural
History Museum, National University of Singapore. Carapace
length (cl), an indication of specimen size, was measured
along the dorsal midline from the tip of the rostrum to theposterior margin of the carapace. For the species reported
in this paper, only original references, primary synonyms
and regional reports are provided.

Although local porcellanid faunas in the Indian Ocean
have been sporadically studied (e.g., Haig, 1965, 1966a,
1966b, 1983; Tirmizi et al., 1989; Hiller et al., 2010),
many of these studies focused on the western areas such as
the continental coasts from India to Iran, Madagascar, andSeychelles. For Christmas Island in the southeastern Indian
Ocean, there are only three reports on porcellanids. In his
list of decapod crustaceans from the island, Calman (1909)
firstly recorded three species: Petrolisthes coccineus (Owen,
1839) with doubt, Petrolisthes dentatus (H. Milne Edwards,
1837), and Pachycheles sculptus (H. Milne Edwards, 1837).
Johnson (1960) subsequently added Neopetrolisthes ohshimai
Miyake, 1937a (as the genus Petrolisthes Stimpson, 1858)
to the local fauna. Most recently, Orchard (2012) included
Petrolisthes lamarckii (Leach, 1820) in his book “Crabs ofChristmas Island”. On the other hand, there are no reports
on porcellanids from the Cocos (Keeling) Islands, which is
the island group nearest to Christmas Island, albeit distantby about 900 km.

SYSTEMATIC ACCOUNT
Family PORCELLANIDAE Haworth, 1825
Neopetrolisthes maculatus (H. Milne Edwards, 1837)(Fig. 1A, B)
Porcellana maculata H. Milne Edwards, 1837: 253 [type locality:
New Ireland, by subsequent designation; see Haig (1965)]
Neopetrolisthes ohshimai Miyake, 1937a: 35, unnumbered fig.
[type locality: Ishigaki Island, Ryukyu Islands]
Petrolisthes ohshimai – Johnson, 1960: 164Material examined. Christmas Island: stn CI-DIV-10, offWest White Beach, 10°27.733’S, 105°35.054’E, sand andgravel bottom, 29 January 2010, 1 male (cl 10.8 mm), ZRC
2013.0821; stn CI-D05-2011, off West White Beach, 10°27.733’S, 105°35.054’E, 1–12.3 m depth, sand and gravelbottom, 25 March 2011, 1 ovigerous female (cl 11.4 mm),
ZRC 2013.0822.

Research Center for Coastal Lagoon Environments, Shimane University, 1060
Nishikawatsu-cho, Matsue, Shimane 690-8504, Japan; Email: osawam@soc.
shimane-u.ac.jp© National University of Singapore
ISSN 2345-7600 (electronic) | ISSN 0217-2445 (print)

255

Osawa: Porcellanidae from Christmas and Cocos (Keeling) Islands
Colour in life. Carapace and abdomen white, with numerous
reddish purple or red spots; frontal and lateral regions withslightly or distinctly smaller spots than those on other regions;
gastric and branchial regions with brown shades aroundspots. Ocular peduncles and third maxillipeds white, withfew small, reddish purple or red spots. Chelipeds generally
white, with small to moderately large, reddish purple or red
spots on dorsal surfaces of merus, carpus and palm; carpus
with spots slightly or distinctly larger on median part than on
marginal parts, median part also with brown shades aroundspots; palm with small and moderately large, purple or red
spots and bearing brown shades around spots on posterior
half. Ambulatory legs white; merus with numerous small,
reddish purple or red spots on proximal half to two-thirds oflateral surface.

105°40.028’E, intertidal, coralline rocks, large boulders,mixed with coral rubble and sand, and few live corals, 11
February 2012, 1 male (cl 2.5 mm), ZRC 2013.0824.

Distribution. Widely distributed in the Indo-West Pacific.
From east Africa to Christmas Island and Western Australia,
Bismarck Archipelago, Queensland, Moluccas, Palau,
Taiwan, southern Japan, New Caledonia, Marshall and Fiji
Islands. Shallow subtidal; coral and rocky reefs, associatedwith large sea anemones (Cryptodendrum, Entacmaea,
Gyrostoma, Heteractis, Stichodactyla), typically found ina heterosexual pair (Davie, 2002; Osawa & Chan, 2010;
Poupin & Junker, 2010).

Distribution. Christmas Island, Nansha and Xisha Islands,
Guam, Caroline, Loyalty Islands, and Ellice Islands, Samoa;
coral reefs, 2–20 m (Osawa, 2007).

Colour in life. Carapace white with some dark red blotches
and spots, or dark red with broad white stripe on midline.
Abdomen white. Ocular peduncles white or pale red,corneas red. Third maxillipeds entirely white. Chelipeds
dorsally mostly white, or red with white parts distally on
palm and dactylus. Ambulatory legs generally dark red
on lateral surface, with white bands on merus, carpus andpropodus; merus with proximal and distal bands, proximal
much broader than distal; carpus with narrow band distally;
propodus with proximal and distal bands subequal in width;
dactylus pale brown.

Remarks. Although Haig (1966c) treated the record of
Pachycheles sculptus by Calman (1909) from Christmas
Island as misidentification of P. spinipes, she or othersubsequent authors never mentioned the reason of theidentification in their publications. The present specimens
confirm the occurrence of P. spinipes at Christmas Island.
Pachycheles spinipes is unique in the genus in having thecarapace with elevated squamae on the gastric region andchelipeds and ambulatory legs bearing strongly projecting,thorn-shaped tubercles (see Haig, 1966c; Osawa, 2007).

Remarks. As mentioned above, the two specimens
examined have different colour and spot patterns. The colourof the spots of the female specimen (ZRC 2013.0822) is red,
whereas that of the male (ZRC 2013.0821) is purple. The
spots on the carapace, and carpus and palm of the cheliped
are sparser, larger, and more irregular in the female than themale.

The specimens examined have two colour forms as shown in
Fig. 1C, D. The possession of a median white stripe on the
carapace and intraspecific variations of the colour pattern
are also noted and illustrated by Haig (1965) and Osawa &Chan (2010) for other congeners, P. johnsoni Haig, 1965, P.
pisoides (Heller, 1865), and P. sculptus.

Although N. ohshimai Miyake, 1937 was described on thebasis of a heterosexual pair of the uneven large blotchpattern, there are intraspecific variations in the colour andsize of the spots and N. ohshimai is now regarded as a juniorsynonym of N. maculatus (Haig, 1965, 1979; Osawa &Fujita, 2001). As shown in the larval study of N. maculatus
by Fujita & Osawa (2003), differences in colouration are
not related to each sex and a male/female pair of similar
colouration has been found in a same host. The spot patternsof the present specimens from Christmas Island fall into
the range of variation between the two colour forms of N.
maculatus illustrated by Osawa & Chan (2010: figs. 65, 66).

Petrolisthes asiaticus (Leach, 1820)(Fig. 1E)
Pisidia asiatica Leach, 1820: 54 [type locality: Isle of France(Mauritius)]
Petrolisthes leporinoides Ortmann, 1892: 263 [type locality: South
Seas]
Petrolisthes yaeyamensis Miyake, 1937b: 157, unnumbered fig.
[type locality: Ishigaki Island, Ryukyu Islands]

Pachycheles spinipes (A. Milne-Edwards, 1873)(Fig. 1C, D)

Material examined. Cocos (Keeling) Islands: stn CK-08,
Trannies Beach, West Island, 12°08.507’S, 96°49.095’E,
intertidal, sandy beach with coral rubbles, 20 March 2011, 4
males (cl 8.1–9.8 mm), 1 female (cl 6.9 mm), ZRC 2013.0825;
stn CK-25, Off William Keeling Crescent, Settlement, West
Island, 12°11.544’S, 96°49.884’E, intertidal, sandy beach toreef flat with sea grass beds and rocky bottom, 24 March
2011, 3 males (cl 3.9–6.6 mm), 1 female (cl 3.8 mm), 1
ovigerous female (cl 6.8 mm), ZRC 2013.0826; stn CK209, Westward reef flats, behind Tropika Restaurant, West
Island, 12°11.297’S, 96°49.726’E, intertidal, exposed reef
flats with sea grass patches, 6 February 2012, 1 male (cl8.7 mm), 1 ovigerous female (cl 7.2 mm), ZRC 2013.0827;

Porcellana spinipes A. Milne-Edwards, 1873: 262 [type locality:
Upalu, Samoa]
Porcellana sollasi Whitelegge, 1897: 144, pl. 7, fig. 3, 3a [typelocality: Funafuti Atoll, Ellice Islands]? Pachycheles sculptus – Calman, 1909: 706

Material examined. Christmas Island: stn CI3-15, Flying
Fish Cove, 10°25.791’S, 105°40.028’E, intertidal, coralline
rocks, large boulders, mixed with coral rubble and sand, andfew live corals, 10 February 2012, 2 males (cl 2.0, 2.6 mm),
ZRC 2013.0823; stn CI3-17, Flying Fish Cove, 10°25.791’S,
256

RAFFLES BULLETIN OF ZOOLOGY 2014
stn CK2-21, Trannies Beach, West Island, 12°08.507’S,
96°49.095’E, intertidal, 11 February 2012, 1 juvenile (cl 2.9mm), 1 male (cl 10.4 mm), 1 female (cl 8.4 mm), 1 ovigerous
female (cl 6.6 mm), ZRC 2013.0828.

Sumatra, Moluccas. Pacific Ocean: Philippines, Guangxi
Province in China, Taiwan, southern Japan (from Izu
Islands to Ryukyu Islands), Mariana Islands, Palau, northern
Australia, Caroline Islands, New Caledonia, Fiji, Tuvalu(Ellice Islands), Rotuma, Western Samoa, Phoenix Islands.
Intertidal, found under rocks (Osawa & Chan, 2010). Now
from the Cocos (Keeling) Islands in the southeastern Indian
Ocean.

Colour in life. The colouration of the present material
agrees well with that provided by Osawa & Chan (2010: fig.
86), although the ground colouration varies from brown tobluish brown.

Remarks. The specimens examined agree well with theprevious descriptions of P. asiaticus (e.g., Miyake, 1942;
Kropp, 1984; Osawa & Chan, 2010).

Distribution. Widely distributed in the Indo-West Pacific.
Indian Ocean: Seychelles, Mauritius, Gulf of Thailand,

Fig. 1. Entire animal in dorsal view, showing colouration in life. A, Neopetrolisthes maculatus (H. Milne Edwards, 1837), male (cl 10.8 mm),
ZRC 2013.0821, stn CI-DIV-10; B, Neopetrolisthes maculatus (H. Milne Edwards, 1837), ovigerous female (cl 11.4 mm), ZRC 2013.0822,
stn CI-D05-2011; C, Pachycheles spinipes (A. Milne-Edwards, 1873), male (cl 2.6 mm), ZRC 2013.0823, stn CI3-15; D, Pachycheles
spinipes (A. Milne-Edwards, 1873), male (cl 2.0 mm), ZRC 2013.0823, stn CI3-15; E, Petrolisthes asiaticus (Leach, 1820), male (cl 8.7mm), ZRC 2013.0827, stn CK2-09; F, Petrolisthes fimbriatus Borradaile, 1898, male (cl 4.1 mm), ZRC 2013.0834, stn CI3-15.

257

Osawa: Porcellanidae from Christmas and Cocos (Keeling) Islands
Material examined. Christmas Island: stn CI-03, Ethel
Beach, 10°27.805’S, 105°42.443’E, intertidal, limestonebase rock, 22 January 2010, 1 male (cl 5.7 mm), 1 ovigerous
female (cl 6.2 mm), ZRC 2013.0830; stn CI-09-2011, Ethel
Beach, 10°27.805’S, 105°42.443’E, intertidal, limestonebase rock, 21 March 2011, 1 male (cl 2.8 mm), ZRC
2013.0831; stn CI-17-2011, Waterfall Bay (Christmas
Island Resort), 10°27.54’S, 105°42.30’E, intertidal, 23
March 2011, 1 juvenile (cl 2.0 mm), 2 ovigerous females (cl5.4, 6.2 mm), ZRC 2013.0832; stn CI-27-2011, Waterfall
Bay (Christmas Island Resort), 10°27.54’S, 105°42.30’E,
intertidal, 25 March 2011, 1 male (cl 6.7 mm), ZRC
2013.0833; stn CI3-15, Flying Fish Cove, 10° 25.791’S,
105°40.028’E, intertidal, coralline rocks, large boulders,mixed with coral rubble and sand, and few live corals, 10
February 2012, 1 male (cl 4.1 mm), 1 ovigerous female (cl3.2 mm), ZRC 2013.0834; stn CI3-16, Flying Fish Cove,
10°25.791’S, 105°40.028’E, intertidal, coralline rocks, large
boulders, mixed with coral rubble and sand, and few live
corals, 11 February 2012, 1 female (cl 4.3 mm), 1 ovigerous
female (cl 5.7 mm), ZRC 2013.0835; stn CI3-17, Flying
Fish Cove, Flying Fish Cove, 10°25.791’S, 105°40.028’E,
intertidal, coralline rocks, large boulders, mixed withcoral rubble and sand, and few live corals, 11 February
2012, 1 juvenile (cl 1.6 mm), 6 males (cl 2.5–4.1 mm), 3
ovigerous females (cl 3.9–6.1 mm), ZRC 2013.0836; stn
CI3-23, Waterfall Bay, 10°27.54’S, 105°42.30’E, intertidal,
boulders, rocks and sand, with pools at low tide, and few
live corals, 13 February 2012, 2 males (cl 5.9, 6.3 mm), 2
ovigerous females (cl 5.1, 6.7 mm), ZRC 2013.0837; stn
CI3-25, Flying Fish Cove, 10°25.791’S, 105°40.028’E,
intertidal, coralline rocks, large boulders, mixed with coral
rubble and sand, and few live corals, 14 February 2012, 1
female (cl 5.8 mm), ZRC 2013.0838.

Petrolisthes asiaticus is the sole porcellanid species collectedfrom the Cocos (Keeling) Islands, but it was not obtained by
the present expeditions to Christmas Island.
The Futuna specimen referred to P. haswelli Miers, 1884 by
Poupin & Junker (2010: 129, fig. a) actually belongs to P.
asiaticus because it has the characteristic colouration of thelatter species and a dorsomedian longitudinal crest of shortridges on the palm of the cheliped.
Petrolisthes bispinosus Borradaile, 1900
(Fig. 2A, B)
Petrolisthes bispinosus Borradaile, 1900: 422 [type locality: Lifu,
Loyalty Islands]

Material examined. Christmas Island: stn CI-D06-2011,
Thunderdome Cave, 10°27.906’S, 105°36.465’E, 3–16.6
m depth, submarine cave, 26 March 2011, 1 female (cl 7.2mm), ZRC 2013.0829.
Colour. Although the fresh colouration of the present
specimen was not recorded, the colour pattern in preserved
condition generally agrees with that of P. bispinosus
provided by Haig & Kropp (1987), particularly in having
reticulated markings on the carapace and chelipeds.
Distribution. Known from various tropical islands in thewestern Pacific: Mariana, Caroline, Marshall, Loyalty,
Howland, Phoenix, and Society Islands, Samoa. Intertidal
to a depth of 6 m; generally found under small blocks andboulders or on pieces of dead coral rubble (Haig & Kropp,1987). The present specimen from Christmas Island represents
the first record of P. bispinosus from the Indian Ocean.
Remarks. There were no illustrations of P. bispinosus until
Haig & Kropp (1987) adequately redescribed the species.
Although the present specimen agrees well with the Haig
& Kropp’s (1987) description, additional illustrations of
the poorly known species are herein provided to show thespecific colour pattern and some morphological characterson the carapace.

Colour in life. Carapace and abdomen brown, withnumerous pale blue spots and some dark brown spots.
Ocular peduncles white with brown blotch on anterior part.
Third maxillipeds generally brown, with pale blue markings
on ischium and merus; propodus and dactylus orange.
Chelipeds brown, with numerous pale blue spots on dorsal
surface; carpus and palm with some dark brown and orange
spots; distal tip of fixed finger orange; dactylus orange on
proximal part of cutting edge and distal tip. Ambulatory legs
greenish brown on lateral surface, with irregular pale blue
spots on merus and carpus; propodus reddish brown, withwhite bands on submedian and distal parts; dactylus white,with pale red blotch medially

General morphology of the carapace and pereopods links
P. bispinosus to P. moluccensis (De Man, 1888), but thearmature on the carapace and ambulatory legs readily
distinguishes the two species. The epibranchial spines on the
carapace are two pairs in P. bispinosus (Fig. 2B), instead of
one pair in P. moluccensis. The outer orbital angle is acutely
pointed in P. bispinosus (Fig. 2B), but it is not produced in
P. moluccensis. The ventral margin of the dactylus of each
ambulatory leg is armed with four corneous spines in P.
bispinosus, unlike only three spines in P. moluccensis (seeOsawa & Chan, 2010: figs. 117, 118).

Distribution. Nansha and Xisha Islands, Philippines, New
Guinea, New Caledonia, Caroline, Marshall, Ellice, Tonga,
and Phoenix Islands. Intertidal, underneath rocks on reef
flats (Osawa, 2007). The present material from Christmas
Island represents the first record of P. fimbriatus from theIndian Ocean.

Petrolisthes fimbriatus Borradaile, 1898
(Fig. 1F)

Remarks. As discussed by Osawa (1998), P. fimbriatus
is closely allied to P. obtusifrons Miyake, 1937c (as P.
varicolour Osawa, 1998), but is best distinguished fromthe latter by the convex instead of subparallel, medianPetrolisthes lamarckii var. fimbriatus Borradaile, 1898: 466 [typelocality: Rotuma, South Pacific]

258

RAFFLES BULLETIN OF ZOOLOGY 2014

Fig. 2. Entire animal in dorsal view, showing colouration in preservative (A) or life (C, D). A, Petrolisthes bispinosus Borradaile, 1900,
female (cl 7.2 mm), ZRC 2013.0829, stn CI-D06-2011; B, same, showing carapace enlarged; C, Petrolisthes lamarckii (Leach, 1820),
ovigerous female (cl 10.2 mm), ZRC 2013.0840, stn CI-09-2011; D, Petrolisthes scabriculus (Dana, 1852), ovigerous female (cl 5.6 mm),
ZRC 2013.0842, stn CI-D12-2011.

branchial margins of the carapace. For fresh colouration,
P. fimbriatus differs from P. obtusifrons in that the pale
blue or white markings on the carapace and chelipeds are
generally uniform and rounded rather than irregular-shaped,
although the ground colour of the latter species is variable(see Osawa & Chan, 2010: fig. 119; Osawa & McLaughlin,
2010: fig. 2C). The colouration of the present material of
P. fimbriatus agrees well with that of the Futuna specimen
provided by Poupin & Junker (2010: 127, fig. a).

base rock, 2 February 2010, 1 male (cl 10.7 mm), 2 females(cl 4.6, 11.4 mm), 1 ovigerous female (cl 9.5 mm), ZRC
2013.0839; stn CI-09-2011, Ethel Beach, 10°27.805’S,
105°42.443’E, intertidal, limestone base rock, 21 March
2011, 1 ovigerous female (cl 10.2 mm), ZRC 2013.0840.

Pisidia lamarckii Leach, 1820: 54 [type locality: not specified]
Porcellana dentata H. Milne Edwards, 1837: 251 [type locality:
Java]
Porcellana pulchripes White, 1847: 129 [nomen nudum]
Porcellana speciosa Dana, 1852: 417 [type localities: DrummondIsland, Kingsmills Group; Wake Island; Mangsi Islands,
Philippines; Raraka, Tuamotu Archipelago]
Porcellana bellis Heller, 1865: 76 [type locality: Nicobar]
Petrolisthes dentatus – Calman, 1909: 706
Petrolisthes lamarckii – Orchard, 2012: 57

Colour in life. Based on an ovigerous female (cl 10.2mm, ZRC 2013.0840) from stn CI-09-2011. Carapace
greenish brown, with irregular-shaped dark brown blotches
symmetrically arranged and with numerous white spots.
Abdomen brown, with irregular transverse line of reddish
brown blotches on each segment and covered with whitespots. Ocular peduncles greenish brown. Third maxillipeds
greenish brown dark greenish brown; dactylus and ventral
margin of propodus orange. Chelipeds greenish brown withirregular dark brown blotches on dorsal surface; tips offingers and proximal end of cutting edge of dactylus pinkishorange. Ambulatory legs generally greenish brown withnumerous white spots on lateral surface; merus and carpus
with irregular dark brown blotches; propodus dark reddish
brown, with white bands proximally and distally; dactylus
red, with proximal white patch.

Material examined. Christmas Island: stn CI-31, Ethel
Beach, 10°27.805’S, 105°42.443’E, intertidal, limestone

Distribution. Throughout the tropical Indo-West Pacific,
westward to eastern African coast and Red Sea, eastward

Petrolisthes lamarckii (Leach, 1820)(Fig. 2C)

259

Osawa: Porcellanidae from Christmas and Cocos (Keeling) Islands
Remarks. The present specimen agrees well with the
published descriptions of P. pubescens (e.g., Kropp, 1986;
Osawa & Chan, 2010).

to Line and Tuamotu Islands; intertidal, found under rocks(Osawa & Chan, 2010).
Remarks. Calman (1909) listed Petrolisthes dentatus fromChristmas Island. Kropp (1984) mentioned that a photographof the type of Porcellana dentata shows four fairly welldeveloped teeth on the dorso-anterior margin of the carpusof the cheliped which the late Janet Haig informed him issuggestive of Petrolisthes haswelli. Nevertheless, as notedby Osawa & Chan (2010), this feature can be present in P.
lamarckii.

Petrolisthes scabriculus (Dana, 1852)(Fig. 2D)
Porcellana scabricula Dana, 1852: 424 [type locality: Sulu Sea]

Material examined. Christmas Island: stn CI-D12-2011,
Thunderdome Cave, 10°27.906’S, 105°36.465’E, 3–16.6
m depth, submarine cave, 28 March 2011, 1 ovigerous
female (cl 5.6 mm), ZRC 2013.0842; stn CI-D14-2011,
Perpendicular Wall, 10°26.722’S, 105°33.641’E, reef slopeand crest, 29 March 2011, 1 female (cl 4.5 mm), ZRC
2013.0843; stn CI-D15-2011, Boat Cave, 10°26.722’S,
105°33.641’E, reef slope and crest, 29 March 2011, 1
juvenile (cl 2.3 mm), 2 males (cl 4.6, 5.7 mm), 2 ovigerous
females (cl 4.9, 5.2 mm), ZRC 2013.0844; stn CI-D17-2011,
Thunderdome Cave, 10°27.906’S, 105°36.465’E, 3–16.6 m
depth, submarine cave, 30 March 2011, 1 male (cl 5.4 mm),
1 female (cl 3.3 mm), ZRC 2013.0845; stn CI-D18-2011,
Rhoda Wall, off Rhoda Beach., 10°27.729’S, 105°37.283’E,
5–16 m depth, reef slope and crest, 30 March 2011, 1 male(cl 5.3 mm), 1 female (cl 3.8 mm), ZRC 2013.0846.

The present specimens all were collected from Ethel Beach,and have the following characters: the rostrum is weakly
trilobate; a pair of the epigastric spines are small or welldeveloped; the carpus of each cheliped is armed with fouror five teeth on the dorso-anterior margin, the distal-most
tooth is occasionally obsolete. The female (cl 11.4 mm, ZRC
2013.0839) from stn CI-31 differs from the other specimens
examined in the colouration of the chela and the armature of
the second pereopod (first ambulatory leg). The chela of thefemale has a row of orange spots along the anterior margin,
but such a row of spots is absent in the other specimens. The
merus of the second pereopod of the female is armed witha more strongly developed spine at the ventrolateral distal
end than that of the other specimens, and the carpus bears asmall dorsodistal spine which is absent in the others. These
characters of the single female agree with those of one of
two forms of P. lamarckii reported by Osawa & Chan (2010:
figs. 109–111, 113d–f).

Colour in life. The colouration of the specimens examined
agrees well with that of P. scabriculus provided by Osawa& Chan (2010: fig. 123).
Distribution. Gulf of Thailand, Philippines, Indonesia, New
Guinea, western and eastern Australia, Nansha Islands in theSouth China Sea, Taiwan, Ryukyu Islands, New Caledonia,
Loyalty Islands. Shallow water to a depth of 55 m, often
associated with corals (Osawa & Chan, 2010). Now fromChristmas Island in the southeastern Indian Ocean.

As mentioned above, the colouration in life was recorded
only for an ovigerous female (cl 10.2 mm, ZRC 2013.0840)
from stn CI-09-2011. The overall colour is brighter and thedark brown blotches on the carapace are larger than thosereported by Osawa & Chan (2010: figs. 109–111).

Remarks. The present specimens agree well with the
published descriptions and illustrations of P. scabriculus(e.g., Nakasone & Miyake, 1968; Osawa, 2007; Osawa &Chan, 2010). As mentioned above, Petrolisthes scabriculus
is known as a shallow subtidal species, although many of thecongeners usually inhabit intertidal region.

Petrolisthes pubescens Stimpson, 1858
Petrolisthes pubescens Stimpson, 1858: 228 [type locality: Foukow
Bay (= Naze Bay), Amami-Oshima, Ryukyu Islands]

Material examined. Christmas Island: stn CI3-16, Flying
Fish Cove, 10°25.791’S, 105°40.028’E, intertidal, coralline
rocks, large boulders, mixed with coral rubble and sand, andfew live corals, 11 February 2012, 1 ovigerous female (cl8.7 mm), ZRC 2013.0841.

ACKNOWLEDGEMENTS
I am grateful to the team members of the expeditions toChristmas Island and the Cocos (Keeling) Islands from 2010
to 2012 (Peter K. L. Ng, Peter J. F. Davie, Max Orchard,
Yoshihisa Fujita, Joelle C. Y. Lai, Jose C. E. Mendoza, Tohru
Naruse, Hsi-Te Shih, Heok Hui Tan, Kai Xin Tan, Siong
Kiat Tan, Swee Hee Tan) for their efforts in collecting thepresent material. I also thank Shane T. Ahyong (AustralianMuseum) and an anonymous referee for reviewing themanuscript.

Colour. Although the fresh colouration of the present
specimen was not recorded, the colour pattern in preserved
condition generally agrees with that of P. pubescens
provided by Osawa & Chan (2010: fig. 121) and Osawa &McLaughlin (2010: fig. 2D).
Distribution. Red Sea, Mauritius, Moluccas, Taiwan,
southern Japan, Ryukyu Islands, Queensland, New Caledonia
and Marquesas Islands. Intertidal to shallow subtidal, foundunder rocks and corals (Osawa & Chan, 2010). Now fromChristmas Island in the southeastern Indian Ocean.

260

RAFFLES BULLETIN OF ZOOLOGY 2014
LITERATURE CITED

Hiller A, Harkantra S & Werding B (2010) Porcellanid crabs from
Goa, eastern Arabian Sea (Crustacea: Decapoda: Porcellanidae).
Journal of the Bombay Natural History Society, 107: 201–212.
Johnson DS (1960) On a porcelain crab, Petrolisthes ohshimai(Miyake), from Christmas Island, Indian Ocean, with a note on
the genus Neopetrolisthes Miyake. Crustaceana, 1: 164–165.
Kropp RK (1984) Three new species of Porcellanidae (Crustacea:
Anomura) from the Mariana Islands and a discussion of
Borradaile’s Petrolisthes lamarckii complex. Micronesica, 19:
91–106. [Issue dated December 1983]
Kropp RK (1986) A neotype designation for Petrolisthes tomentosus(Dana), and description of Petrolisthes heterochrous, newspecies, from the Mariana Islands (Anomura: Porcellanidae).
Proceedings of the Biological Society of Washington, 99:452–463.
Leach WE (1820) Galatéadées, Galateadæ. (Crust.). In: Cuvier
F (ed.) Dictionnaire des Sciences Naturelles, dans lequelon trait Méthodiquement des Différens étres de la Nature,
considérés soit en eux-mêmes, d’après l’état actuel de nos
connoissances, soit relativement a l’utilité qu’en peuvent retirer
la Médecine, l’Agriculture, le Commerce et les Arts. Suivi d’une
biographie des plus Célèbres Naturalistes. Ouvrage destiné auxmédecins, aux agriculteurs, aux commerçans, aux artistes, aux
manufacturiers, et à tous ceux qui ont intérêt à connoître les
productions de la nature, leurs caractères génériques et spécifi
ques, leur lieu natal, leurs propiétés et leurs usages. Volume
18. Levrault FG et Le Normant, Strasbourg et Paris, pp. 49–56.
Miers EJ (1884) Crustacea. In: Report on the Zoological Collections
made in the Indo-Pacific Ocean during the Voyage of H.M.S.
‘Alert’ 1881–2. British Museum, London, pp. 178–322,
513–575.
Milne-Edwards A (1873) Description de quelques crustacés
nouveaux ou peu connus provenant du Musée de M. C.
Godeffroy. Journal des Museum Godeffroy, 4: 253–264.
Milne Edwards H (1837) Histoire naturelle des Crustacés,comprenant l’anatomie, la physiologie et la classification de ces
animaux, 2: 1–532, atlas, 32 pp., 42 pls. Librairie Encylopédiquede Roret, Paris.
Miyake S (1937a) A new crab-shaped anomuran living commensallywith a gigantic sea-anemone (Neopetrolisthes ohshimai gen. et
sp. nov.). Zoological Magazine, Tokyo, 49: 34–36.
Miyake S (1937b) Note on Petrolisthes yaeyamensis sp. nov.
(Anomura, Porcellanidae). Zoological Magazine, Tokyo, 49:
157–158.
Miyake S (1937c) Description of a new species of Petrolisthes
from Yaéyama-Group, Riukiu Islands (Anomura, Porcellanidae).
Zoological Magazine, Tokyo, 49: 155–157.
Miyake S (1942) Studies on the decapod crustaceans of Micronsia.
III. Porcellanidae. The Palau Tropical Biological Station
Studies, 2: 329–379.
Naderloo R & Apel M (2014) A new species of porcelain crab,
Petrolisthes tuerkayi n. sp. (Crustacea: Anomura: Porcellanidae),from the Persian Gulf. Zootaxa, 3881: 190–194.
Nakasone Y & Miyake S (1968) Four unrecorded porcellanid crabs(Anomura: Porcellanidae) from Okinawa, the Ryukyu Islands.
OHMU (Occasional Papers of Zoological Laboratory, Facultyof Agriculture, Kyushu University, Fukuoka, Japan), 1: 97–111.
Orchard M (2012) Crabs of Christmas Island. Christmas Island
Natural History Association, 287 pp.
Ortmann A (1892) Die Decapoden-Krebse des Strassburger
Museums, mit besonderer Berücksichtigung der von Herrn Dr.
Döderlein bei Japan und bei den Liu-Kiu-Inseln gesammelten
und zur Zeit im Strassburger Museum aufbewahrten Formen.
IV. Die Abtheilungen Galatheidea und Paguridea. Zoologischen
Jahrbücher, Abtheilung für Systematik, Geographie und Biologie
der Thiere, 6: 241–326.

Ahyong ST, Baba K, Macpherson E & Poore GCB (2010) A
new classification of the Galatheoidea (Crustacea: Decapoda:
Anomura). Zootaxa, 2676: 57–68.
Borradaile LA (1898) On some crustaceans from the South Pacific.
Part II. Macrura Anomala. Proceedings of the Zoological Societyof London, 1898: 457–468.
Borradaile LA (1900) On the Stomatopoda and Macrura brought by
Dr Willey from the south seas. In: Willey A (ed.) ZoologicalResults based on Material from New Britain, New Guinea,
Loyalty Islands and Elsewhere, collected during the Years
1895, 1896 and 1897. Part IV. Cambridge University Press,
Cambridge, pp. 395–428.
Calman WT (1909) On decapod Crustacea from Christmas Island,collected by Dr. C. W. Andrews, F.R.S., F.Z.S. Proceedings ofthe General Meetings for Scientific Business of the ZoologicalSociety of London, 1909: 703–713, pl. 72.
Dana JD (1852–1853) Crustacea. United States Exploring
Expedition during the Years 1838, 1839, 1840, 1841, 1842,
under the Command of Charles Wilkes, U.S.N., 13: i–viii,
1–685 [1852], 686–1818 [1853]. Sherman C, Philadelphia.
(Reprinted Antiquariaat Junk, Lochem, 1972.)
Davie PJF (2002) Crustacea: Malacostraca: Eucarida (Part 2):
Decapoda-Anomura, Brachyura. In: Wells A & Houston
WWK (eds.) Zoological Catalogue of Australia. Volume 19.
3B. CSIRO Publishing, Melbourne, xiv+641 pp.
De Man JG (1888) Bericht über die von Herrn Dr. J. Brock im
indischen Archipel gesammelten Decapoden und Stomatopoden.
Archiv für Naturgeschichte, 53: 289–600.
Fujita Y & Osawa M (2003) Zoeal development of two spot-patternmorphs of Neopetrolisthes maculatus, and of N. spinatus(Crustacea: Decapoda: Anomura: Porcellanidae), reared underlaboratory conditions. Species Diversity, 8: 175–198.
Haig J (1965) The Porcellanidae (Crustacea, Anomura) of Western
Australia with description of four new Australian species.
Journal of the Royal Society of Western Australia, 48: 97–117.
Haig J (1966a) Sur une collection de Crustaces Porcellanes(Anomura: Porcellanidae) de Madagascar et des Comores.
Cahiers O.R.S.T.O.M., sèrie Ocèanographie, 3: 39–50.
Haig J (1966b) The Porcellanidae (Crustacea Anomura) of the
Iranian Gulf and Gulf of Oman. Videnskabelige Meddelelser
Dansk Naturhistrisk Forening i Kjøbenhavn, 129: 49–65.
Haig J (1966c) A review of the Indo-West Pacific species of genus
Pachycheles (Porcellanidae, Anomura). Proceedings of the
Symposium on Crustacea held at Ernakulam from January 12
to 15, 1965, Part I: 285–294. Marine Biological Associationof India, Bangalore.
Haig J (1979) Expèdition Rumphius II (1975) Crustacèsparasites, commensaux, etc. (Th. Monod et R. Serène, éd.).
V. Porcellanidae (Crustacea, Decapoda, Anomura). Bulletindu Muséum National d’Histoire Naturelle, Paris, 4e, section
A, 1: 119–135.
Haig J (1983) Porcellanidae (Decapoda, Anomura) from the
Seychelles, western Indian Ocean. Crustaceana, 45: 279–289.
Haig J & Kropp RK (1987) Petrolisthes eldredgei, a new porcellanidcrab from the Indo-West Pacific, with redescription of two
related species. Micronesica, 20: 171–186.
Haworth AH (1825) A new binary arrangement of the macrurous
Crustacea. The Philosophical Magazine and Journal, 65:
105–106, 183–184.
Heller C (1865) Crustaceen. In: Reise der öesterreichischen Fregatte
Novarra um die Erde, in den Jahren 1857, 1858, 1859, unterden Befehlen des Commodore B. von Wüllerstorf-Urbair.
Zoologischer Theil, 2(3). Kaiserlich-königlichen Hof- und
Staatsdruckerei, Wien, 280 pp.

261

Osawa: Porcellanidae from Christmas and Cocos (Keeling) Islands
Osawa M (1998) Two rare species of the genus Petrolisthes(Decapoda: Anomura: Porcellanidae) from the Ryukyu Islands,
with the description of a new species of the genus. Journal of
Crustacean Biology, 18: 597–615.
Osawa M (2007) Porcellanidae (Crustacea: Decapoda: Anomura)from New Caledonia and the Loyalty Islands. Zootaxa, 1548:
1–49.
Osawa M & Chan TY (2010) Part III. Porcellanidae (Porcelaincrabs). In: Chan TY. (ed.) Crustacean Fauna of Taiwan: Crablike Anomurans (Hippoidea, Lithodoidea and Porcellanidae).
National Taiwan Ocean University, Keelung, pp. 67–181.
Osawa M & Fujita Y (2001) A new species of the genus
Neopetrolisthes Miyake, 1937 (Crustacea: Decapoda:
Porcellanidae) from the Ryukyu Islands, southwestern Japan.
Proceedings of the Biological Society of Washington, 114:
162–171.
Osawa M & McLaughlin PA (2010) Annotated checklist of
anomuran decapod crustaceans of the world (exclusive of the
Kiwaoidea and families Chirostylidae and Galatheidae of theGalatheoidea) Part II – Porcellanidae. In: Low MEY & Tan
SH (eds.) Checklists of Anomuran Decapod Crustaceans of theWorld (Exclusive of the Kiwaioidea and Families Chirostylidae
and Galatheidae of the Galathoidea) and Marine Lobsters of theWorld. Raffles Bulletin of Zoology, Supplement 23: 109–129.
Osawa M & Uyeno D (2013) A new subtidal species of thegenus Petrolisthes Stimpson, 1858 (Crustacea: Decapoda:
Porcellanidae) from Okinawa, with an account of species of
the genus known from the Ryukyu Islands, southwestern Japan.
Zootaxa, 3670: 329–338.

Owen R (1839) Crustacea. In: The Zoology of Captain Beechey’s
Voyage; Compiled from the Collections and Notes made by
Captain Beechey, the Officers and Naturalist of the Expedition,
during a Voyage to the Pacific and Behring’s Straits performedin His Majesty’s Ship Blossom, under the command of Captain
F. W. Beechey, R.N., F.R.S., in the Years 1825, 26, 27 and28. Bohn HG, London, pp. 77–92.
Poupin J & Juncker M (2010) Guide des Crustaces Decapodes duPacifique Sud / A Guide to Decapod Crustaceans of the South
Pacific. CRISP and CPS, Noumea, 317 pp.
Stimpson W (1858) Prodromus descriptionis animalium
evertebratorum, quae in Expeditione ad Oceanum Pacificum
Septentrionalem, a Republica Federata missa, Cadwaladaro
Ringgold et Johanne Rodgers Ducibus, observavit et descripsit.
Pars VII. Crustacea Anomura. [Preprint (December 1858)from] Proceedings of the Academy of Natural Sciences ofPhiladelphia, 1858: 225–252.
Tirmizi NM, Yaqoob M & Siddiqui FA (1989) Marine Fauna ofPakistan: 3 Porcellanid Crabs (Crustacea, Anomura). Centreof Excellence in Marine Biology, University of Karachi,
Karachi, 46 pp.
White A (1847) List of the specimens of Crustacea in the collectionof the British Museum. British Museum, London, 143 pp.
Whitelegge T (1897) The Crustacea of Funafuti. In: Atoll of
Funafuti, Ellice Group: Its Zoology, Botany, Ethnology, andGeneral Structure based on Collections made by Mr. Charles
Hedley, of the Australian Museum, Sydney, N.S.W. Memoirsof the Australian Museum, 3: 125–151, pls. 6, 7.

262