RAFFLES BULLETIN OF ZOOLOGY 2019
Taxonomy & Systematics
RAFFLES BULLETIN OF ZOOLOGY 67: 217–246

Date of publication: 3 April 2019
DOI: 10.26107/RBZ-2019-0018
http://zoobank.org/urn:lsid:zoobank.org:pub:0656D7C5-0498-40B6-9348-284800EE671D

The vampire crabs of Java, with descriptions of five new species from
Mount Halimun Salak National Park, West Java, Indonesia (Crustacea:
Brachyura: Sesarmidae: Geosesarma)
Peter K. L. Ng1 & Daisy Wowor2
Abstract. Six species of vampire crabs, Geosesarma noduliferum (De Man, 1892), G. confertum (Ortmann, 1894),
G. rouxi (Serène, 1968a), G. bicolor Ng & Davie, 1995, G. dennerle Ng, Schubart & Lukhaup, 2015, and G. hagen
Ng, Schubart & Lukhaup, 2015, are known thus far from Java, Indonesia. All are endemic to the island. Surveys inand around Mount Halimun Salak National Park in West Java showed that the sesarmid crab fauna for the islandis much richer, and five new species are described. The new taxa are described, figured, and compared with theirclosest congeners. Two poorly known species, G. confertum and G. rouxi are also re-diagnosed and figured. A key
to the known species of Geosesarma from Java is also provided.
Key words. semiterrestrial crab, Indonesia, Java, taxonomy, new species, protected areas

INTRODUCTION[Cilacap], and G. hagen Ng, Schubart & Lukhaup, 2015
[Cilacap]; and one species from East Java: G. rouxi (Serène,
1968a) [Poedjon].

The freshwater sesarmid crab fauna of Java has been
increasing studied in recent years, and six species ofGeosesarma De Man, 1892, and two species of Karstarma
Davie & Ng, 2007, are now known (cf. Ng et al., 2015;
Wowor & Ng, 2018). The diversity of Geosesarma inparticular, popularly known as vampire crabs, is especiallyhigh, and some 59 species are now known from theAndamans, Thailand, Malaysia, Indonesia, Papua New
Guinea, Philippines, and Taiwan (Ng, 2017). As most ofthese species practice direct development (i.e., their large
eggs hatch into very advanced non-feeding zoeae or as
juvenile crabs (cf. Ng, 1988; Ng & Tan, 1995; Soh, 1969),
many Geosesarma species have very restricted distributions,with different species sometimes occurring just 10 km fromeach site (see Ng et al., 2015), compounding the challenge
for taxonomists.

Collections in and around Mount Halimun Salak National
Park (or Taman Nasional Gunung Halimun Salak) in WestJava and Banten Provinces in 2015 and 2016 as part of theIndonesia-German INDOBIOSYS (Indonesian Biodiversity
and Information System) project resulted in a good collectionof Geosesarma specimens. Additional collections were
subsequently made in 2017. A joint study of this material
and other specimens obtained from several previous surveys
around Bogor and Cipanas of Banten Province by the second
author showed that five species are represented, all of which
are new to science. These new species, as well as the current
taxa, are diagnosed, figured and compared with their closest
species. A new genus and new species of gecarcinucid crab
has already been described from near the summit of Mount
Halimun (Ng & Wowor, 2018).

From West Java, three species are known at present:
G. noduliferum (De Man, 1892) [Bogor], G. confertum(Ortmann, 1894) [Tjibodas or Gunung Gede], and G. bicolor
Ng & Davie, 1995 [Ujung Kulon,], with two species fromCentral Java: G. dennerle Ng, Schubart & Lukhaup, 2015

MATERIAL AND METHODS
Material examined is deposited in the Museum Zoologicum
Bogoriense (MZB), Cibinong, Bogor, Indonesia; and the
Zoological Reference Collection (ZRC) of the Lee Kong
Chian Natural History Museum (ex-Raffles Museum of
Biodiversity Research), National University of Singapore.
Indonesian words use in the text are S. or Sungai for riveror stream; Gunung for mountain; Ds. or Desa for village;
Kp. or Kampung for hamlet. The collectors were D. Wowor,
U. Nurhaman, and S. Sauri, which is written as D. Wowor
et al., unless otherwise stated.

Lee Kong Chian Natural History Museum, Faculty of Science, National Universityof Singapore, 2 Conservatory Drive, Singapore 117377, Republic of Singapore;
Email: peterng@nus.edu.sg

1

Division of Zoology, Research Center for Biology, Indonesian Institute of Sciences(LIPI), Jalan Raya Jakarta Bogor Km 46, Cibinong 16911, Indonesia; Email:daisy_wowor@yahoo.com

2

Both authors contributed equally to this work*

© National University of Singapore
ISSN 2345-7600 (electronic) | ISSN 0217-2445 (print)217

Ng & Wowor: New Geosesarma crabs from Java
The terminology used mostly follows that in Ng (1988)
with recent changes in Davie et al. (2015). Measurements
provided in millimetres are of the carapace width and length,
respectively. The following abbreviations are used: m asl= metres above sea level; coll. = collected by; G1 = malefirst gonopod; G2 = male second gonopod. The position was
obtained by using GPS (Garmin eTrex Vista C), while theelevation was acquired by the software GPS Geoplaner –GeoConverter (https://www.geoplaner.com/).

1 male (poorly preserved, 10.7 × 9.5 mm), 1 female (7.2 ×
6.5 mm) (MZB Cru 4448), Tenjolaya District, Ds. Tapos
1, Kp. Sinar Wangi, S. Ciampea at the border of Gunung
Bunder Resort, 06°40′46.6″S 106°41′39.6″E, 775 m asl,coll. D. Wowor et al., 2 October 2015; 2 males (8.5 × 7.6mm, 9.3 × 8.9 mm), 3 females (9.9 × 8.5 mm – 10.9 × 10.4mm) (MZB Cru 3403), Taman Sari District, Ds. Sukajadi,
Kp. Gadog Sisi, S. Cihideung, 06°39′03.7″S 106°43′15.3″E,
562 m asl, coll. D. Wowor et al., 26 September 2011; 1
male (9.9 × 9.1 mm) (MZB Cru 3407), 1 male (10.9 ×
10.4 mm) (ZRC 2018.0282 ex-MZB Cru 3407), Tenjolaya
District, Ds. Gunung Malang, Kp. Cibitung, S. Cibitung,06°39′01.5″S 106°43′09.3″E, 551 m asl, coll. D. Wowor etal., 27 September 2011; 2 males (10.1 × 9.2 mm, 11.3 ×
10.5 mm), 2 females (8.2 × 7.2 mm, 8.3 × 7.3 mm) (MZB
Cru 3014), 2 males (12.1 × 11.4 mm, 12.7 × 11.7 mm), 2
females (10.0 × 8.6 mm, 10.5 × 8.9 mm) (ZRC 2018.0283
ex-MZB Cru 3014), Megamendung District, Ds. Sukaresmi,
S. Cisukabirus, 06°42′09.7″S 106°54′43.7″E, 800 m asl, coll.
D. Wowor et al., 10 May 2010; 2 males (8.4 × 7.8 mm, 12.3
× 10.9 mm), 1 female (10.1 × 9.3 mm) (MZB Cru 4644),
Bogor Selatan District, Ds. Katulampa 2, S. Ciliwung,
06°38′03.6″S 106°50′24.9″E, 370 m asl, coll. D. Wowor etal., 26 July 2009; 2 males (11.1 × 10.2 mm, 11.8 × 10.4 mm),
1 ovigerous female (10.9 × 10.5 mm, eggs 1.5 mm diameter)(MZB Cru 4645), Megamendung District, Ds. Sukamanah,
S. Cisukabirus, 06°41′12.8″S 106°54′08.0″E, 703 m asl, coll.
D. Wowor et al., 24 July 2009. Cianjur Regency: 8 males(10.5 × 9.5 mm – 14.5 × 13.5 mm), 2 females (12.3 × 11.3mm, 12.6 × 11.4 mm) (MZB Cru 4646), 4 males (12.9 ×
11.5 mm – 13.7 × 12.8 mm) (ZRC 2018.0284 ex-MZB Cru
4646), Sukaresmi District, Ds. Cibadak, Kp. Rawa Benceh,
S. Ciwalen at rice field, coll. U. Komarudin, 24 July 2009;19 males (8.0 × 7.4 mm – 13.9 × 12.2 mm), 12 females (9.4
× 8.1 mm – 12.7 × 11.7 mm), 5 ovigerous females (9.6 ×
8.6 mm – 11.3 × 10.6 mm, 1 female with juveniles in pouch(11.4 × 9.9 mm) (MZB Cru 4643), Cipanas District, Ds.
Sindanglaya, at vegetable garden, coll. U. Komarudin, 24
July 2009. Banten Province, Lebak Regency: 3 males (8.8 ×
8.4 mm, 10.9 × 10.2 mm, 11.3 × 10.6 mm), 5 females (8.4 ×
7.3 mm – 10.9 × 10.2 mm) (MZB Cru 4796), 3 males (9.6
× 8.9 mm, 10.4 × 9.5 mm, 13.3 × 12.4 mm), 2 females (9.6
× 9.3 mm, 10.9 × 9.6 mm) (ZRC 2018.0294 ex-MZB Cru
4796), Banten Province, Lebak Regency, Cipanas District,
Ds. Cipanas, 06°32′54.9″S 106°23′55.7″E, 184 m asl, coll.
D. Wowor, I. Rachmatika & A. Mun’im, 30 August 2005.

TAXONOMYFamily Sesarmidae Dana, 1851
Geosesarma De Man, 1892
Type species. Sesarma (Geosesarma) nodulifera De Man,
1892, subsequent designation by Serène & Soh (1970).
Remarks. The genus continues to grow as more areas are
surveyed and new taxa discovered; with the total now standingat 59 (Ng, 2017). The number of Geosesarma species known
from Indonesia is certain to grow, and the authors are awareof more populations, some with distinctive colours, which
will need to be studied. From Java, six species are knownat present: G. noduliferum (De Man, 1892) [Bogor, west
Java], G. confertum (Ortmann, 1894) [Tjibodas, west Java],
G. rouxi (Serène, 1968a) [Poedjon, east Java], G. bicolor
Ng & Davie, 1995 [Ujung Kulon, Banten], G. dennerle Ng,
Schubart & Lukhaup, 2015 [Cilacap, central Java], and G.
hagen Ng, Schubart & Lukhaup, 2015 [Cilacap, central
Java]. In this paper, we redescribe the first three species aswell as describe five new species from forests surrounding
Mount Halimun Salak National Park in West Java.
Geosesarma noduliferum (De Man, 1892)(Figs. 1–4)
Sesarma (Geosesarma) nodulifera De Man, 1892: 342, pl. 20, fig.
16; Nobili, 1900: 512 (part).
Sesarma(Geosesarma) nodulifera – Ortmann, 1894: 56; Serène,
1968b: 106.
Sesarma (Geosesarma) noduliferum – Rathbun, 1910: 309.
Sesarma (Sesarma) nodulifera – De Man, 1902: 519; Tesch,
1917: 178.
Geosesarma noduliferum – Serène & Soh, 1970: 402, 407; Ng,
1988: 119; Ng et al., 2008: 221; Ng e al., 2015: 3, figs. 1A,
B, 2A–E, 5A, B.
(not Sesarma (Geosesarma) noduliferum – Serène 1968a: 1094,
figs. 19, 20 = Geosesarma confertum [Ortmann, 1892]).

Revised diagnosis of male. Carapace squarish, wider thanlong, lateral margins gently concave, subparallel (Figs. 1A,
B, 2A, C, E, 3A, B); dorsal surface with distinct regions,anterior regions with numerous small rounded granules (Figs.
1B, C, 2E, 3A, B); front deflexed, frontal lobes very broadwith almost truncate margins, separated by broad medianconcavity; postfrontal cristae sharp (Figs. 1B, C, 2E, 3A, B);
external orbital tooth triangular, directed obliquely outwards,
tip reaching anterior part of lateral carapace margin, firstepibranchial tooth triangular, well defined, separated frommargin by distinct cleft (Figs. 1B, 2E). Ischium of third
maxilliped ovate, wide; exopod relatively slender, withlong flagellum that extends beyond merus width (Fig. 4A).

Material examined. West Java Province, Bogor City: 1
male (12.0 × 11.0 mm) (MZB Cru 4888), Bogor Timur
District, Ds. Tajur, coll. M. Djajasasmita, 24 December
1977; 2 males (10.8 × 9.4 mm, 11.2 × 9.9 mm), 7 females(7.4 × 6.6 mm – 11.8 × 10.4 mm), 1 ovigerous female(12.0 × 10.9 mm, eggs 1.8 mm diameter) (MZB Cru 4889),
Bogor Barat District, Ds. Cilendek Barat, S. Cisadane,
06°34′54.8″S 106°46′30.7″E, 202 m asl, 21 December 2017.
Bogor Regency: 3 males (9.3 × 8.9 mm – 10.9 × 9.9 mm),
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Fig. 1. Geosesarma noduliferum (De Man, 1892), male (10.9 × 10.4 mm) (ZRC 2018.0282). A, overall dorsal view; B, dorsal view ofcarapace; C, frontal view of cephalothorax; D, anterior thoracic sternum, telson and pleonal somites 4–6; E, outer view of left chela; F,
dorsal view of dactylus of left chela.

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Fig. 2. Geosesarma noduliferum (De Man, 1892). A, B, male (12.1 × 11.4 mm) (ZRC 2018.0283); C–G, male (12.7 × 11.7 mm) (ZRC
2018.0283). A, C, overall dorsal view; B, D, anterior thoracic sternum, telson and pleonal somites 4–6; E, dorsal view of carapace; F,
outer view of left chela; G, dorsal view of dactylus of left chela.

Outer surface of palm of adult male chelae granulate; innersurface granulated but without prominent transverse comblike ridge; dorsal margin of dactylus with 11–13 (usually
10 or 11) evenly spaced small tubercles (last one near tip
often very small), each with chitinous tip (Figs. 1E, F, 2F,
G). Ambulatory legs with relatively broad meri, with sharp
subdistal spine on dorsal margin, surfaces gently rugose;
ventral margins of propodus and dactylus of adult firstambulatory leg with scattered stiff setae (Figs. 1A, 2A, C,

3A, B). Male pleon triangular; telson triangular with rounded
tip, slightly longer than broad; somite 6 with convex lateral
margins (Figs. 1D, 2B, D, 4B, C). G1 relatively slender,
subdistal part of outer margin before chitinous distal partrounded with inner dorsal section relatively slender; chitinous
distal part bent about 40° along longitudinal axis, elongate,
tapering, slender in lateral view, subspatuliform in mesial
view; tip clefted when viewed dorsally (Figs. 4D–F, H–J,
6D–F).

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Fig. 3. Geosesarma noduliferum (De Man, 1892). A, male (10.9 × 10.4 mm) (ZRC 2018.0282); B, male (12.7 × 11.7 mm) (ZRC 2018.0283);
C–E, female (10.5 × 8.9 mm) (ZRC 2018.0283). A–C, overall dorsal view; B, anterior thoracic sternum, telson and pleonal somites 4–6;
C, sternopleonal cavity showing vulvae.

Females. The adult female carapace is relatively broader andmore trapezoidal in general shape (Fig. 3C). The vulvae areon the anterior half of sternite 6, raised, directed obliquely
inwards towards the median line of the sternum, the margin isindented medially and without a sternal opercular cover (Fig.
3E). The eggs of ovigerous females were between 1.8 mm(MZB Cru 4889) and 1.5 mm in diameter (MZB Cru 4645).

proportions and the shape of somite 6, varies to some degree.
Some of the smaller specimens tend to have a slightly wider
male somite 6 with the lateral margins slightly more convex(Fig. 1D) compared to larger ones (Figs. 2B, D, 4B, C); andthe chitinous distal part of the G1 varies slightly in length
as well (Fig. 4F, J).
See General Discussion for comparisons with allied Javan
species.

Remarks. Examination of the good series of specimensof G. noduliferum obtained by the second author from thelower slopes of Mount Salak requires a revised diagnosis forthis species which is common in the habitats outside Bogor,
especially in view of the new allied species recognised here
(G. lebak, new species). The present study augments andupdates the description and figures of the type by Ng et al.
(2015). The form of the male pleon, notably the general

Notes on habitat. It is found mainly at the side ofmoderate-fast current streams, under the stones nearby
human settlement, rice field and tea plantation (Fig. 25A).
Sometimes it can be encountered in holes at the moist wallof a river. Besides that, the species also inhabits edge of
secondary forest with soft ground, in holes among dense221

Ng & Wowor: New Geosesarma crabs from Java

Fig. 4. Geosesarma noduliferum (De Man, 1892). A, D–G, male (10.9 × 10.4 mm) (ZRC 2018.0282); B, male (12.1 × 11.4 mm) (ZRC
2018.0283); C, H–J, male (12.7 × 11.7 mm) (ZRC 2018.0283). A, left third maxilliped; B, C, male pleonal somite 6 and telson; D, H,
left G1 (dorsal view); E, I, left G1 (ventral view); F, J, left G1 (dorso-mesial view); G, left G2. All structures denuded. Scales: A–C =1.0 mm; D–J = 0.5 mm.

weed. Those places are open area with very little canopy
coverage. Geosesarma noduliferum is a middle stretch stream
species live between 170 to 800 m asl.

S. Cimaja, 06°39′15.7″S 106°21′43.7″E, 536 m asl, coll. D.
Wowor et al., 26 May 2016; 6 males (8.2 × 7.4 mm – 11.7
× 11.1 mm), 5 females (7.9 × 7.0 mm – 11.2 × 10.3 mm)(MZB Cru 4551), 1 male (10.8 × 9.6 mm), 2 females (11.8
× 10.4 mm, 12.2 × 10.6 mm) (ZRC 2018.0286 ex-MZB
Cru 4551), Sobang District, Ds. Majasari, Kp. Majaharja,
S. Cigehong, a small tributary at the back of Jaro M. Yunus(head of village) home, 06°39′07.4″S 106°22′05.5″E, 588
m asl, coll. D. Wowor et al., 28 May 2016.

Life colouration. The carapace is reddish dark brown todark blue with yellow eyes and bright maroon chelae.
Distribution. Widespread in Bogor and Cianjur Regencies,
West Java Province, and Lebak Regency, Banten Province.
Geosesarma lebak, new species(Figs. 5, 6A–C, 7)

Diagnosis of male. Carapace squarish, wider than long, lateral
margins gently concave, subparallel (Fig. 5A, B); dorsal
surface with distinct regions, anterior regions with numerous
small rounded granules (Fig. 5B, C); front deflexed, frontal
lobes very broad with almost truncate margins, separated bybroad median concavity; postfrontal cristae sharp (Fig. 5B, C);external orbital tooth triangular, directed obliquely outwards,
tip slightly extending beyond anterior part of lateral carapace
margin, first epibranchial tooth triangular, well defined,
separated from margin by distinct cleft (Fig. 5B). Ischiumof third maxilliped ovate, wide; exopod relatively slender,
with long flagellum that extends beyond merus width (Fig.
7A). Outer surface of palm of adult male chelae granulate;inner surface granulated but without distinct transverse comb-

Material examined. Banten Province, Lebak Regency:
holotype: male (11.7 × 11.3 mm) (MZB Cru 4563),
Sobang District, Ds. Majasari, S. Cimaok, ca. 06°38′35.5″S106°22′22.0″E, 685 m asl, coll. Ibu Warung, 28 May 2016.
Paratypes: 10 males (9.9 × 9.0 mm – 11.7 × 11.1 mm), 1
female (9.7 × 9.4 mm) 1 female (damaged, 10.9 mm carapace
width) (MZB Cru 4648), 2 males (11.0 × 10.7 mm, 11.2 ×
10.8 mm) (ZRC 2018.0285 ex-MZB Cru 4648), data same
as holotype; 7 males (7.6 × 7.0 mm – 11.3 × 10.5 mm),
6 females (8.6 × 7.6 mm – 12.9 × 11.5 mm), 2 juveniles(MZB Cru 4553), Sobang District, Ds. Majasari, Kp. Maja,
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Fig. 5. Geosesarma lebak, new species, holotype male (11.7 × 11.3 mm) (MZB Cru 4563). A, overall dorsal view; B, dorsal view ofcarapace; C, frontal view of cephalothorax; D, anterior thoracic sternum, telson and pleonal somites 4–6; E, thoracic sternum, telson andpleonal somites 3–6; F, outer view of right chela; G, dorsal view of right chela; H, dorsal view of dactylus of right chela.

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Fig. 6. A–C, Geosesarma lebak, new species, paratype female (12.2 × 10.6 mm) (ZRC 2018.0286); D, G. noduliferum (De Man, 1892),
male (11.3 × 10.6 mm) (MZB Cru 4796); E, F, G. noduliferum (De Man, 1892), male (10.9 × 10.2 mm) (MZB Cru 4796); G, H, G.
lebak, new species, paratype male (11.2 × 10.8 mm) (ZRC 2018.0285). A, overall dorsal view; B, anterior thoracic sternum, telson andpleonal somites 4–6; C, sternopleonal cavity showing vulvae; D, E, G, left G1 (dorsal view); F, H, distal part of left G1 (dorsal view).

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Fig. 7. Geosesarma lebak, new species, holotype male (11.7 × 11.3 mm) (MZB Cru 4563). A, left third maxilliped; B, left G1 (dorsalview); C, left G1 (ventral view); D, left G1 (ventro-mesial view); E, left G1 (dorso-mesial view); F, left G2. All structures denuded.
Scales: A = 1.0 mm; B–F = 0.5 mm.

Etymology. The species is named after the locality where
the holotype of the new species was found. The name isused as a noun in apposition.

like ridge; dorsal margin of dactylus with 10 or 11 evenly
spaced small tubercles (last one near tip may be very small),each with chitinous tip (Fig. 5F–H). Ambulatory legs withrelatively broad meri, with sharp subdistal spine on dorsal
margin, surfaces gently rugose; ventral margins of propodus
and dactylus of adult first ambulatory leg with scattered stiff
setae (Fig. 5A). Male pleon triangular; telson triangular withrounded tip, longer than broad; somite 6 with convex lateral
margins (Fig. 5D, E). G1 relatively slender, subdistal part ofouter margin before chitinous distal part angular with inner
dorsal section strongly developed; chitinous distal part bent
about 45º along longitudinal axis, elongate, tapering, slenderin lateral view, subspatuliform in mesial view; tip clefted
when viewed dorsally (Figs. 6G, H, 7B–E).

Remarks. See General Discussion for comparisons withallied Javan species.
Notes on habitat. This species inhabits side of slow-moderatecurrent streams, under the cobbles nearby human settlement
and rice field. It can be also found under the cobbles of driedtributaries but with the substrate still moist (Fig. 25B). The
habitat is open area with little canopy coverage. Geosesarma
lebak, new species, lives between 500 to 700 m asl.
Life colouration. It has reddish dark brown carapace, yellow
eyes and bright red chelae (Fig. 26A).

Females. The adult female carapace is slightly broader andmore trapezoidal in form (Fig. 6A). The vulvae are on theanterior half of sternite 6, raised, directed obliquely inwards
towards the median line of the sternum, the margin is indented
medially and without a sternal opercular cover (Fig. 6C).

Distribution. Lebak Regency in Banten Province, in Gunung
Bongkok Resort of Mount Halimun Salak National Park.

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Fig. 8. Geosesarma sukabumi, new species, holotype male (11.5 × 10.3 mm) (MZB Cru 4555). A, overall dorsal view; B, dorsal view ofcarapace; C, frontal view of cephalothorax; D, anterior thoracic sternum, telson and pleonal somites 5 and 6; E, anterior thoracic sternum,
telson and pleonal somites 3–6; F, outer view of right chela; G, dorsal view of right chela; H, dorsal view of dactylus of right chela.

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Fig. 9. Geosesarma sukabumi, new species, paratype female (10.3 × 9.2 mm) (MZB Cru 4647). A, overall dorsal view; B, anterior thoracic
sternum, telson and pleonal somites 4–6; C, sternopleonal cavity showing vulvae.

Geosesarma sukabumi, new species(Figs. 8–10)

of lateral carapace margin, first epibranchial tooth truncate,well defined, separated from margin by small cleft (Fig. 8B).
Ischium of third maxilliped ovate; exopod relatively slender,
with long flagellum that extends just beyond merus width(Fig. 10A). Outer surface of palm of adult male chelae withlow granules and rugae; inner surface granulated but withouttransverse comb-like ridge; dorsal margin of dactylus with
3 or 4 distinct large tubercles on proximal third, each withchitinous tip (Fig. 8F–H). Ambulatory legs with relatively
broad meri, with sharp subdistal spine on dorsal margin,
surfaces rugose; ventral margins of propodus and dactylus ofadult first ambulatory leg with dense comb-like setae. Malepleon triangular; telson triangular with rounded tip, as longas broad; somite 6 wide, with convex lateral margins (Fig.
8D, E). G1 relatively stout, subdistal part of outer margin
before chitinous distal part gently curved with inner dorsal
section strongly developed; chitinous distal part bent about
80º along longitudinal axis, tapering, relatively slender inlateral view, spatuliform in mesial view; tip rounded whenviewed dorsally (Fig. 10B–E).

Material examined. West Java Province, Sukabumi
Regency: holotype: male (11.5 × 10.3 mm) (MZB Cru 4555),
Cikakak District, Ds. Cirendang, Kp. Paniisan, cliff nearby
S. Cirendang, 06°53′57.0″S 106°33′11.1″E, 587 m asl, coll.
D. Wowor et al., 18 May 2016. Paratypes: 13 males (6.3 ×
5.5 mm – 10.5 × 9. 1 mm), 8 females (5.2 × 4.7 mm – 10.4
× 9.9 mm), 2 juveniles (MZB Cru 4647), 1 male (10.3 × 9.0mm), 1 female (9.2 × 8.0 mm) (ZRC 2018.0287 ex-MZB
Cru 4647), same data as holotype.
Diagnosis of male. Carapace subquadrate, slightly wider
than long, lateral margins sinuous, gently divergent (Fig.
8A, B); dorsal surface with clear regions, anterior regionswith numerous small rounded granules (Fig. 8B, C); front
deflexed, frontal lobes broad with convex margins, separated
by broad, shallow median concavity; postfrontal cristae
sharp (Fig. 8B, C); external orbital tooth triangular, directed
obliquely outwards, tip extending slightly beyond anterior part227

Ng & Wowor: New Geosesarma crabs from Java

Fig. 10. Geosesarma sukabumi, new species, holotype male (11.5 × 10.3 mm) (MZB Cru 4555). A, left third maxilliped; B, left G1(dorsal view); C, left G1 (ventral view); D, left G1 (ventro-mesial view); E, left G1(dorso-mesial view); F, left G2. All structures denuded.
Scales: A = 1.0 mm; B–F = 0.5 mm.

Females. The adult female carapace is more trapezoidal inform (Fig. 9A). The vulvae are on the anterior half of sternite
6, slightly raised, directed obliquely inwards towards themedian line of the sternum, the margin is indented mediallyand without a sternal opercular cover (Fig. 9C).

Distribution. Sukabumi Regency in West Java Province, in
Gunung Koneng Resort of Mount Halimun Salak National
Park.
Geosesarma robustum, new species(Figs. 11, 12)Etymology. The species is named after the region where
it was found, Sukabumi Regency. The name is used as anoun in apposition.

Material examined. West Java Province, Bogor Regency:
holotype: male (9.6 × 9.2 mm) (MZB Cru 4452), Tenjolaya
District, Ds. Tapos 1, Kp. Sinar Wangi, near dam at
headwaters of S. Ciampea, in middle of primary forest,
06°41′36.0″S 106°42′23.7″E, 1,032 m asl, coll. D. Wowor
et al., 2 October 2015.

Remarks. See General Discussion for comparisons withallied Javan species.
Notes on habitat. The species was found under wet leaf
litter, with water seeping from the base of a cliff, not far
from a stream at the edge of a small hamlet. The ground isa mixture of gravel and coarse sand. The habitat is about
12.6 m above the stream, shadowed by trees grow on thecliff at around 580 m asl (Fig. 25C).

Diagnosis of male. Carapace quadrate, slightly wider thanlong, lateral margins almost straight, slightly divergent (Fig.
11A, B); dorsal surface with clear regions, anterior regionswith numerous small granules (Fig. 11B, C); front deflexed,
frontal lobes broad with gently convex margins, separatedby shallow median concavity; postfrontal cristae sharp (Fig.
11B, C); external orbital tooth triangular, directed obliquely
outwards, tip extending just beyond anterior part of lateralcarapace margin, first epibranchial tooth truncate, barely
separated from margin by small cleft (Fig. 11B). Ischiumof third maxilliped ovate; exopod relatively slender, withLife colouration. The carapace and chelae are dark brownwith black eyes.

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Fig. 11. Geosesarma robustum, new species, holotype male (9.6 × 9.2 mm) (MZB Cru 4452). A, overall dorsal view; B, dorsal view ofcarapace; C, frontal view of cephalothorax; D, anterior thoracic sternum, telson and pleonal somites 5 and 6; E, anterior thoracic sternum,
telson and pleonal somites 3–6; F, outer view of right chela; G, dorsal view of right chela; H, dorsal view of dactylus of right chela.

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Fig. 12. Geosesarma robustum, new species, holotype male (9.6 × 9.2 mm) (MZB Cru 4452). A, left third maxilliped; B, left G1 (dorsalview); C, left G1 (ventral view); D, E, left G1 (ventro-mesial view); F, left G1(dorso-mesial view); G, left G2. All structures denuded.
Scales: A = 1.0 mm; B–G = 0.5 mm.

Notes on habitat. It was found at the side of head water
stream, under cobbles of 10 to 20 m diameter with a bitof water (Fig. 25D). It is in an open area far from humansettlement, surrounded by forest. It is a highland species
that lives above 1,000 m asl.

long flagellum that extends just beyond merus width (Fig.
12A). Outer surface of palm of adult male chelae with low
granules; inner surface granulated but without transverse
comb-like ridge; dorsal margin of dactylus with 3 distinct
large tubercles on proximal third, each with chitinoustip (Fig. 11F–H). Ambulatory legs with relatively broadmeri, with sharp subdistal spine on dorsal margin, surfaces
rugose; ventral margins of propodus and dactylus of adultfirst ambulatory leg with dense comb-like setae. Male pleon
triangular; telson triangular with rounded tip, as long as
broad; somite 6 trapezoidal, with gently convex to almost
straight lateral margins (Fig. 11D, E). G1 very stout, short,
subdistal part of outer margin before chitinous distal partgently angular with inner dorsal section strongly developed;
chitinous distal part bent about 45° along longitudinal axis,
short, truncate in lateral view, spatuliform in mesial view;
tip truncate when viewed dorsally (Fig. 12B–F).

Life colouration. The carapace is purplish dark brown withblack eyes and dark brown chelae.
Distribution. Bogor Regency in Jawa Barat Province, in
Gunung Bunder Resort of Mount Halimun Salak National
Park.
Geosesarma confertum (Ortmann, 1894)(Figs. 13–15)
Sesarma (Geosesarma) sp. De Man, 1892: 345.
Sesarma (Geosesarma) nodulifera var. conferta Ortmann, 1894: 56.
Sesarma (Geosesarma) noduliferum – Serène, 1968a: 1093, text
figs. 19, 20.
Sesarma (Geosesarma) noduliferum confertum – Serène, 1968b:
106.
Geosesarma confertum – Ng et al., 2008: 220; Ng et al., 2015:
6, fig. 1E, F.

Females. Not known.
Etymology. The name alludes to the stout structure of the G1.
Remarks. See General Discussion for comparisons withallied Javan species.
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Fig. 13. Geosesarma confertum (Ortmann, 1894), male (9.3 × 8.6 mm) (MZB Cru 4797). A, overall dorsal view; B, dorsal view of carapace;C, frontal view of cephalothorax; D, propodus and dactylus of left first ambulatory leg; E, outer view of right chela; F, dorsal view ofdactylus right chela; G, anterior thoracic sternum, telson and pleonal somites 4–6; H, posterior thoracic sternum and pleonal somites 2–6.

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Fig. 14. Geosesarma confertum (Ortmann, 1894), female (11.5 × 10.0 mm) (MZB Cru 4797). A, overall dorsal view; B, anterior thoracic
sternum, telson and pleonal somites 4–6; C, sternopleonal cavity showing vulvae.

Material examined. West Java Province, Cianjur Regency: 2
males (9.4 × 8.5 mm, 10.7 × 9.7 mm) (ZRC 1970.3.7.11–12),
Tjibodas (= Cibodas or Gunung Gede), west Java, don.
Museum Zoologicum Bogoriense, 1960s; 5 juveniles, 20
males (6.9 × 6.6 mm – 9.8 × 9.0 mm), 21 females (8.3 ×
7.3 mm – 11.5 × 10.0 mm), 5 ovigerous females (9.9 × 8.9– 10.1 × 8.9 mm) (MZB Cru 4797), 2 males (9.0 × 8.2 mm,
11.1 × 10.9 mm), 1 female (10.5 × 9.6 mm) (ZRC 2018.0292
ex-MZB Cru 4797), among watercress, at nursery, on edge ofcliff, near Cibogo Waterfall, Kebun Raya Cibodas (= Cibodas
Botanical Garden), 06º44′16.0″S 107º00′38.3″E, 1,286 m
asl, Ds. Sindanglaya, Cipanas District, coll. D. Wowor &U. Nurhaman, 29 Mar 2011; 1 male (11.9 × 11.1 mm, badly
damaged) (MZB Cru 4798), S. Cibogo, walled stream withslow-moderate flow with rock and gravel substrate, canopy
coverage 90%, pH 6.0, Kebun Raya Cibodas (= Cibodas
Botanical Garden), 06°44′18.7″S 107°00′33.7″E, 1,303 masl, Ds. Sindanglaya, Cipanas District, coll. D. Wowor etal., 22 July 2009; 1 male (9.6 × 9.0 mm), 2 females (8.8 ×
7.7 mm, 13.1 × 10.9 mm), 1 ovigerous female (10.2 × 9.4mm, eggs 1.2 mm diameter) (MZB Cru 4799), 1 male (9.8

× 9.0 mm) (ZRC 2018.0293 ex-MZB Cru 4799), in grasscovered holes at water edge, small gutter, near pond, not
far from entrance gate, Kebun Raya Cibodas (= Cibodas
Botanical Garden), Ds. Sindanglaya, Cipanas District, coll.
D. Wowor et al., 23 July 2009; 18 males (7.9 × 7.4 mm –10.6 × 9.6 mm), 14 females (7.8 × 7.3 mm – 11.3 × 10.1mm), 1 ovigerous female (10.3 × 9.3 mm, eggs 1.3 mm
diameter), 8 juveniles (MZB Cru 4961), on cliff covered
with wet moss, Kebun Raya Cibodas (= Cibodas Botanical
Garden), Ds. Sindanglaya, Cipanas District, coll. S. Klaus,
P. Koller & D. Wowor, 31 March 2006.
Diagnosis of male. Carapace subquadrate, wider thanlong, lateral margins gently sinuous, divergent (Figs. 13A,B); dorsal surface with regions, anterior regions with verysmall granules (Fig. 13B, C); front deflexed, frontal lobes
broad with convex margins, separated by shallow medianconcavity; postfrontal cristae relatively sharp (Fig. 13B, C);external orbital tooth triangular, directed obliquely outwards,
tip just reaching or extending slightly beyond anterior part oflateral carapace margin, first epibranchial tooth subtruncate,232

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Fig. 15. Geosesarma confertum (Ortmann, 1894), male (9.3 × 8.6 mm) (MZB Cru 4797). A, left third maxilliped (distal part of flagellum
broken off); B, left G1 (dorsal view); C, left G1 (ventral view); D, left G1 (dorso-mesial view); E, left G1(ventro-mesial view); F, left
G2. All structures denuded. Scales = 0.5 mm.

Remarks. De Man (1892: 345) recorded several small
specimens from “Tjipanas” and Tjibodas from Java as“Sesarma (Geosesarma) sp.”, noting that it was possibly G.
noduliferum except that the dactylus of the male has moreand closely packed tubercles. Ortmann (1894: 56) had morematerial from the same area, observed the same differenceswith G. noduliferum s. str. and decided to recognise a newvariety, G. noduliferum confertum, for this material (seereview in Ng et al., 2015: 6). There is a town called Tjipanas(= Cipanas) further to the west in Lebak Regency, but the“Tjipanas” cited by De Man (1892) almost certainly refers to
the district of Tjipanas (= Cipanas District) which includes
the highlands of Tjibodas on the slopes of Mount Gede.

separated from margin by small cleft (Fig. 13B). Ischiumof third maxilliped short, ovate, wide; exopod relatively
slender, with long flagellum that extends just beyond merus
width (Fig. 15A). Outer surface of palm of adult malechelae with scattered low granules; inner surface granulated
but without transverse comb-like ridge; dorsal margin of
dactylus with 16–19 small tubercles, each with chitinous tip
along length (Figs. 13E, F). Ambulatory legs with relatively
broader, shorter meri, with sharp subdistal spine on dorsal
margin, surfaces rugose; ventral margins of propodus anddactylus of adult first ambulatory leg with dense comb-likesetae (Figs. 13D). Male pleon triangular; telson triangularwith rounded tip, slightly wider than long; somite 6 withconvex lateral margins (Figs. 13G, H). G1 relatively slender,
short, gently curved, subdistal part of outer margin before
chitinous distal part with low convexity, inner dorsal section
strongly developed; chitinous distal part bent about 40º along
longitudinal axis, relatively long, spatulate in lateral view,
subcylindrical in mesial view; tip subtruncate when viewed
dorsally (Fig. 15B–E).

See General Discussion for comparisons with allied Javan
species.
Notes on habitat. It is found in holes at the edge of waterof small gutter and among roots of watercress in wetland.
The water is clear with a slow-moderate current. The habitatis also shadowed by trees. Sometimes it is also occurs under
wet moss on cliff sides. Geosesarma confertum is a highland
species, occuring above 1,280 m asl.

Females. The adult female carapace is more trapezoidal inform (Fig. 14A). The vulvae are without a sternal opercular
cover, ovate and are level with the surface of the anterior
half of sternite 6, and relatively widely separated (Fig. 14C).
The egg diameter of ovigerous females is 1.2 mm (MZB
Cru 4799).

Life colouration. The carapace is dark brown with blackeyes. The chelae are yellowish brown and the ambulatory
legs are with dark brown and yellowish-brown stripes.
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Fig. 16. Geosesarma sekop, new species, holotype male (10.5 × 9.4 mm) (MZB Cru 4455). A, overall dorsal view; B, dorsal view ofcarapace; C, frontal view of cephalothorax; D, anterior thoracic sternum, telson and pleonal somites 4–6; E, anterior thoracic sternum,
telson and pleonal somites 3–6; F, outer view of right chela; G, dorsal view of right chela; H, dorsal view of dactylus of right chela.

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Fig. 17. Geosesarma sekop, new species. A–C, paratype male (12.1 × 10.8 mm) (MZB Cru 4466); D–F, paratype female (11.9 × 10.4mm) (ZRC 2018.0288); A, D, overall dorsal view; B, E, anterior thoracic sternum, telson and pleonal somites 4–6; C, dorsal margin of
dactylus of left chela; F, sternopleonal cavity showing vulvae.

Distribution. The species is known only from and aroundthe highlands of Cibodas in Cianjur Regency at the borderof Mount Gede Pangrango National Park.

of S. Cimuara Herang at Curug Muara Herang in Gunung
Bunder Resort, 06°42′40.8″S 106°41′03.2″E, 1,015 m asl,coll. D. Wowor et al., 3 October 2015. Paratypes: 12 males(8.2 × 7.5 mm – 11.2 × 10.5 mm), 15 females (8.3 × 7.5mm – 10.9 × 9.7 mm), 1 ovigerous female (9.0 × 8.6 mm,
eggs 1.8 mm diameter), 15 juveniles (MZB Cru 4654), 1
male (10.2 × 9.2 mm), 1 female (11.9 × 10.4 mm) (ZRC
2018.0288 ex-MZB Cru 4654), same data as holotype.
Sukabumi Regency: paratypes: 14 males (8.1 × 7.3 mm– 12.1 × 10.8 mm), 3 females (6.6 × 6.0 mm – 12.6 ×

Geosesarma sekop, new species(Figs. 16–18)
Material examined. West Java Province, Bogor Regency:
holotype: male (10.5 × 9.4 mm) (MZB Cru 4455), Pamijahan
District, Ds. Gunung Sari, Kp. Rawa Lega, on moist cliff235

Ng & Wowor: New Geosesarma crabs from Java

Fig. 18. Geosesarma sekop, new species. A–G, holotype male (10.5 × 9.4 mm) (MZB Cru 4455); H, I, male (12.1 × 10.8 mm) (MZB
Cru 4466). A, right third maxilliped; B, H, left G1 (dorsal view); C, I, left G1 (ventral view); D, E, left G1 (ventro-mesial view); F, left
G1(dorso-mesial views); G, right G2. All structures denuded. Scales: A, H, I = 1.0 mm; B–G = 0.5 mm.

11.8 mm), 1 ovigerous female (10.6 × 9.5 mm, eggs 1.7
mm diameter) (MZB Cru Cru 4466), Cidahu District, Ds.
Cidahu, on moist cliff at hiking gate to Kawah Ratu Salak1, 06°44′19.1″S 106°42′52.9″E, 1,214 m asl, coll. D. Wowor
et al., 30 September 2015.

rugose; ventral margins of propodus and dactylus of firstambulatory leg with scattered stiff setae. Male pleon
triangular; telson triangular with rounded tip, as long as broad;somite 6 with convex lateral margins (Figs. 16D, E, 17B).
G1 relatively slender, subdistal part of outer margin before
chitinous distal part gently curved, may be crenulate, with
inner dorsal section strongly developed; chitinous distal part
bent about 30° along longitudinal axis, elongate, spatulate
in lateral view, narrow in mesial view; tip subtruncate whenviewed dorsally (Fig. 18B–F, H, I).

Diagnosis of male. Carapace subquadrate, slightly wider
than long, lateral margins gently sinuous, divergent (Figs.
16A, B, 17A); dorsal surface with regions, anterior regionswith numerous small granules (Fig. 16B, C); front deflexed,
frontal lobes broad with convex margins, separated byshort, shallow median concavity; postfrontal cristae sharp(Fig. 16B, C); external orbital tooth triangular, directed
obliquely outwards, tip not extending beyond anterior part oflateral carapace margin, first epibranchial tooth subtruncate,separated from margin by small cleft (Fig. 16B). Ischiumof third maxilliped ovate, wide; exopod relatively slender,
with long flagellum that extends just beyond merus width(Fig. 18A). Outer surface of palm of adult male chelae with
scattered low granules; inner surface granulated but withouttransverse comb-like ridge; dorsal margin of dactylus with
15–18 small tubercles, each with chitinous tip along length(Figs. 16F–H, 17C). Ambulatory legs with relatively broadmeri, with sharp subdistal spine on dorsal margin, surfaces

Females. The adult female carapace is distinctly more
trapezoidal in form (Fig. 17D). The vulvae are without asternal opercular cover, ovate and are level with the surfaceof the anterior half of sternite 6, and relatively more widely
separated (Fig. 17F). The eggs were between 1.8 mm (MZB
Cru 4654) and 1.7 mm in diameter (MZB Cru Cru 4466).
Etymology. The name is derived from the Indonesian word
“sekop” for spade, alluding to the structure of the G1. The
name is used as a noun in apposition.
Remarks. See General Discussion for comparisons withallied Javan species.

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Notes on habitat. Moist cliffs with water seepage andmoss are the preferred habitats of this species; and these areusually not far from streams. The area has canopy coverage
between 70 and 80%. Geosesarma sekop, new species, lives
above 1,000 m asl.

front deflexed, frontal lobes broad with convex to subtruncate
margins, separated by short, shallow median concavity;
postfrontal cristae sharp (Figs. 19B, C, 20A); external
orbital tooth triangular, directed obliquely outwards, tip notextending beyond anterior part of lateral carapace margin,
first epibranchial tooth subtruncate, separated from margin by
distinct cleft (Figs. 19B, 20A). Ischium of third maxilliped
ovate, wide; exopod relatively slender, with long flagellum
that extends just beyond merus width (Fig. 21A). Outersurface of palm of adult male chelae with small granules;
inner surface granulated but without transverse comb-likeridge; dorsal margin of dactylus with 15–18 small tubercles,
each with chitinous tip along most of length except distal
part (Figs. 19E, F, 20C). Ambulatory legs with relatively
broader, shorter meri, with sharp subdistal spine on dorsal
margin, surfaces rugose; ventral margins of propodus anddactylus of adult first ambulatory leg with dense comb-likesetae. Male pleon triangular; telson triangular with rounded
tip, as long as broad; somite 6 with convex lateral margins(Figs. 19D, 20B). G1 relatively slender, short, gently curved,
subdistal part of outer margin before chitinous distal partvery low with inner dorsal section strongly developed;
chitinous distal part bent about 40° along longitudinal axis,
short, spatulate in lateral view, narrow in mesial view; tip
subtruncate when viewed dorsally (Fig. 21B–D).

Life colouration. The carapace is dark brown with blackeyes and light brown chelae (Fig. 26B).
Distribution. Bogor and Sukabumi Regencies in West Java
Province, in Gunung Bunder and Kawahratu Resorts ofMount Halimun Salak National Park, respectively.
Geosesarma cikaniki, new species(Figs. 19–21)
Material examined. West Java Province, Bogor Regency:
holotype: male (8.9 × 8.7 mm) (MZB Cru 4649), Nanggung
District, Ds. Malasari, 4th tributary from Cikaniki Research
Station, at trail between Cikaniki Research station and Kp.
Citalahap Sentral, in the forest, above 1,108 m asl, coll. D.
Wowor et al., 5 July 2017. Paratypes: 5 males (11.9 × 11.0mm [post molt], 9.0 × 8.2 mm – 9.5 × 9.2 mm), 2 females(8.4 × 7.6 mm, 10.4 × 9.3 mm), 1 ovigerous female (10.1
× 9.2 mm, eggs 1.5 mm diameter), 12 juveniles (MZB Cru
4650), same data as holotype; 5 females (6.8 × 6.2 mm –10.7 × 8.9 mm), 1 juvenile (MZB Cru 4619), Nanggung
District, Ds. Malasari, 4th tributary from Cikaniki Research
Station, at trail between Cikaniki Research station and Kp.
Citalahap Sentral, in the forest, above 1,108 m asl, coll. D.
Wowor et al., 11 May 2016; 8 males (6.7 × 6.3 mm – 10.0
× 9.3 mm), 2 females (6.6 × 6.4 mm, 10.2 × 9.2 mm), 7
juveniles (MZB Cru 4651), Nanggung District, Ds. Malasari,
5th tributary from Cikaniki Research Station, at loop trail
between Cikaniki Research Station and Kp. Citalahap Sentral,in the forest, above 1,108 m asl, coll. D. Wowor et al., 5
July 2017; 1 young (5.9 × 5.3 mm) (MZB Cru 4652), 1
male (11.1 × 9.1 mm) (ZRC 2018.0289 ex-MZB Cru 4652),
Nanggung District, Ds. Malasari, about 30 m down of the
4th tributary from Cikaniki Research Station, coll. D. Wowor
et al., 5 July 2017; 3 males (6.9 × 6.6 mm – 7.4 × 6.9 mm),
2 females (5.9 × 5.4 mm, 7.3 × 6.7 mm), 1 juvenile (MZB
Cru 4653), 2 males (9.2 × 7.9 mm, 11.6 × 10.2 mm), 1
female (10.2 × 9.2 mm) (ZRC 2018.0290 e×-MZB Cru
4653), Nanggung District, Ds. Malasari, a tributary (= S.
Malajegang), on the road to Cikaniki Research Station,
6°44′55.4″S 106°32′26.1″E, 1,093 m, coll. D. Wowor etal., 5 July 2017.

Females. The adult female carapace is distinctly more
trapezoidal in form (Fig. 20D). The vulvae are without asternal opercular cover, ovate and are level with the surfaceof the anterior half of sternite 6, and relatively more widely
separated (Fig. 20F). The egg diameter is 1.5 mm (MZB
Cru 4650).
Etymology. The species is named after the site where it
was first collected, Cikaniki. The name is used as a noun
in apposition.
Remarks. See General Discussion for comparisons withallied Javan species.
Notes on habitat. It lives under pebbles with coarse sandsubstrate. The substrate is always wet due to water seepage.
The habitat is in the middle of highland rain forest withalmost totally under canopy coverage (Fig. 25E). Geosesarma
cikaniki, new species, lives above 1,000 m asl. A new genus
and new species of gecarcinucid, Occulthusa halimun Ng &Wowor, 2018, was recently described from the same area as
this Geosesarma species (Ng & Wowor, 2018).
Life colouration. The carapace is dark brown with blackeyes and purplish brown chelae.

Diagnosis of male. Carapace subquadrate, slightly wider
than long, lateral margins gently sinuous, slightly divergent(Figs. 19A, B, 20A); dorsal surface with regions, anterior
regions with numerous small granules (Figs. 19B, C, 20A);

Distribution. Bogor Regency in West Java Province, in
Cikaniki Resort of Mount Halimun Salak National Park.

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Fig. 19. Geosesarma cikaniki, new species, holotype male (8.9 × 8.7 mm) (MZB Cru 4649). A, overall dorsal view; B, dorsal view ofcarapace; C, frontal view of cephalothorax; D, anterior thoracic sternum, telson and pleonal somites 4–6; E, outer view of left chela; F,
dorsal view of dactylus of left chela.

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Fig. 20. Geosesarma cikaniki, new species. A–C, paratype male (11.9 × 11.0 mm) (MZB Cru 4650); D–F, paratype female (9.9 × 8.9mm) (MZB Cru 4619). A, D, overall dorsal view; B, E, anterior thoracic sternum, telson and pleonal somites 4–6; C, dorsal margin of
dactylus of right chela; F, sternopleonal cavity showing vulvae239

Ng & Wowor: New Geosesarma crabs from Java

Fig. 21. Geosesarma cikaniki, new species, holotype male (8.9 × 8.7 mm) (MZB Cru 4649). A, left third maxilliped; B, left G1 (dorsalview); C, left G1 (ventral view); D, left G1(dorso-mesial views); E, left G2. All structures denuded. Scales = 0.5 mm.

Geosesarma rouxi (Serène, 1968a)(Figs. 22, 23)ovate, wide; exopod relatively slender, with long flagellum
that extends across width of merus (Fig. 23A). Outer surfaceof palm of adult male chelae with spaced out granules;
inner surface granulated but without transverse comb-likeridge; dorsal margin of dactylus with 6 or 7 large tubercles,
each with chitinous tip along most of length except distal
part (Figs. 22F–H). Ambulatory legs with relatively broadmeri, with sharp subdistal spine on dorsal margin, surfaces
rugose; ventral margins of propodus and dactylus of adultfirst ambulatory leg with dense comb-like setae. Male pleon
broadly triangular; telson triangular with rounded tip, as longas broad; somite 6 wide with convex lateral margins (Figs.
22D, E). G1 short, stout, subdistal part of outer margin
before chitinous distal part angular; chitinous distal genty
bent, short, round, subtruncate in lateral view, spatulate inmesial and dorsal views (Fig. 23B–F).

Sesarma (Sesarma) sylvicola – Roux, 1933: 11. (not Sesarma
sylvicola De Man, 1892)
Sesarma (Geosesarma) rouxi Serène, 1968a: 1092, text fig. 15, 16,
pl. 2 fig. 4; Serène, 1968b: 107.
Geosesarma rouxi – Ng et al., 2008: 221.

Material examined. East Java Province, Malang Regency:
paratypes: 2 males (10.0 × 9.5 mm, 12.6 × 12.3 mm) (ZRC
2014.0358), Poedjon (= present day Pujon), cascades, ca.
7°50′37″S 112°28′08″E, Pujon District, East Java, Indonesia,
coll. J. Roux, 16 January 1929.
Diagnosis of male. Carapace quadrate, slightly wider thanlong, lateral margins gently convex, subparallel (Figs. 22A,B); dorsal surface with regions, anterior regions with small
flattened granules (Figs. 22B); front deflexed, frontal lobes
broad with convex margins, separated by median concavity;
postfrontal cristae relatively sharp (Figs. 22B, C); external
orbital tooth triangular, directed obliquely anteriorly, tip notextending beyond anterior part of lateral carapace margin, firstepibranchial tooth low but distinct, separated from margin by
distinct cleft (Figs. 22B). Ischium of third maxilliped short,

Females. Not known.
Remarks. Roux (1933: 11) had reported this taxon as
Sesarma sylvicola De Man, 1892, listing 22 males and 11
females among his collection. Serène (1968a: 1092) argued
it was not De Man’s species and described it as new fromseven males he had on hand: the holotype (11.0 × 11.5 mm),four males which he labelled A–D (10.0 × 10.5 mm, 11.5 ×
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Fig. 22. Geosesarma rouxi (Serène, 1968a), male (12.6 × 12.3 mm) (ZRC 2014.358). A, overall dorsal view; B, dorsal view of carapace;C, frontal view of cephalothorax; D, anterior thoracic sternum, telson and pleonal somites 4–6; E, posterior thoracic sternum and pleonalsomites 1–6; F, outer view of right chela; G, H, dorsal view of dactylus of right chela (different angles).

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Fig. 23. Geosesarma rouxi (Serène, 1968a), male (12.6 × 12.3 mm) (ZRC 2014.358). A, left third maxilliped; B, left G1 (dorsal view);
C, left G1 (ventral view); D, E, left G1 (ventro-mesial views); F, left G1 (dorso-mesial view); G, left G2. All structures denuded. Scales:
A = 1.0 mm; B–G = 0.5 mm.

Fig. 24. Distribution of species in and around Mount Halimun Salak National Park. Geosesarma noduliferum (De Man, 1892) (red circles);G. lebak, new species (yellow circles); G. sukabumi, new species (red square); G. robustum, new species (yellow square); G. confertum(Ortmann, 1894) (red polygon); G. sekop, new species (yellow polygon); G. cikaniki, new species (black polygon). Google Map.

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Fig. 25. Habitats. A, Geosesarma noduliferum habitat, stream at Tenjolaya District, Bogor Regency; B, G. lebak, new species, edge ofS. Cimaja in Banten Province; C, G. sukabumi, new species, cliff face above S. Cirendang, Sukabumi Regency; D, G. robustum, newspecies, head water of S. Ciampea, Bogor Regency; E, G. cikaniki, new species, moist forest in Cikaniki Research Station, Bogor Regency.

Life colouration. Not known.

12.0 m, 9.0 × 9.5 mm, 12.0 × 12.5 mm, respectively) andtwo juveniles. The present two specimens in the ZRC havea small label C and D each, respectively, and are clearly thetwo paratypes listed by him. The type locality was stated to
be “Poedjon (Cascade), (Centre Java, Indonesie)” (Serène,
1968a: 1093), but this is not correct as this location is
actually in East Java, in the highlands northwest of Malang.
The altitude of Pujon is around 1,100 m asl.

Distribution. Known only from the type locality.
GENERAL DISCUSSION
The 11 species of Geosesarma now known from Javacan be separated into four species groups. One group (G.
noduliferum, G. bicolor, G. dennerle, G. hagen, G. lebak)
has a more or less quadrate carapace with the lateral margins
parallel, the dorsal margin of the adult male cheliped dactylus
has 7–11 small tubercles, the G1 is relatively slender withthe chitinous distal part slender in lateral view, and theSee General Discussion for comparisons with allied Javan
species.
Notes on habitat. Not known.

243Ng & Wowor: New Geosesarma crabs from Java

Fig. 26. Colour in life. A, Geosesarma lebak, new species, male (11.3 × 10.5 mm) (MZB Cru 4553), S. Cimaja, Banten Province; B, G.
sekop, new species, holotype male (10.5 × 9.4 mm) (MZB Cru 4455), Curug Muara Herang, Bogor Regency. A, photograph by R.M.
Marwoto; B, photograph by R.K. Hadiaty.

of G. lebak is also proportionately more slender (Fig. 5D)than that of G. noduliferum (Fig. 1D) when specimens ofsimilar sizes are compared. The first lateral carapace toothof G. lebak is also usually more distinctly acute (Fig. 5B)(versus usually relatively broader and usually more truncate
in G. noduliferum; Fig. 1B, 2E); but this character is notreliable for smaller specimens and does vary a bit.

vulvae (when known) are directed obliquely towards themedian part of the sternopleonal cavity. The second group(G. sukabumi, G. robustum) has a quadrate to subquadrate
carapace with the lateral margins slightly diverging, thedorsal margin of the adult male cheliped dactylus has 3 or
4 clear large tubercles, the G1 is stout with the chitinous
distal part tapering in lateral view, and the vulvae (whenknown) are directed obliquely towards the median part of thesternopleonal cavity. The third group (G. confertum, G. sekop,
G. cikaniki) has a subquadrate carapace which is usuallytrapezoidal in shape with the lateral margins diverging,the dorsal margin of the adult male cheliped dactylus has
15–19 small tubercles, the G1 is relatively slender withthe chitinous distal part appearing more spatulate in lateralview, and the vulvae are positioned further apart on thesternopleonal cavity and are almost flat on the surface. The
last group has only one species G. rouxi (Serène, 1968a),and is characterised by its trapezoidal carapace, the dorsal
margin of the adult male cheliped dactylus possessing 5 or
6 large tubercles, and a short and stout G1 with a very shortand almost rounded chitinous distal part.

Two of the new species, G. sukabumi and G. robustum, areunusual among West Javan Geosesarma in that the dorsal
margin of the dactylus of the adult male chela only has 3 or
4 distinct tubercles which are just on the proximal part. In
addition, the G1s of these two species are proportionately
much stouter and broader than those of other Geosesarma
species in west Java. Geosesarma sukabumi can be separated
from G. robustum by the form of its male pleon, which isdistinctly more triangular in G. robustum with somite 6 more
trapezoidal in form (Fig. 11D, E) compared to G. sukabumi,
which is broader with somite 6 more subrectangular (Fig. 8D,E). The most diagnostic difference is in their G1 structures; in
G. sukabumi, the chitinous distal part is bent about 80° along
the longitudinal axis and relatively elongate (Fig. 10B–D)
whereas in G. robustum, the G1 is proportionately muchstouter and wider with the chitinous part very short and bent
at only about 45° along the longitudinal axis (Fig. 12B–F).

For the new species described in this paper, only G. lebak
is in the G. noduliferum group. Geosesarma lebak is very
close to G. noduliferum in the general carapace features but
is most effectively separated by its G1, with the general
structure relatively stouter and the subdistal part of outermargin more angular in shape (Figs. 6G, H, 7B, C) (versus
G1 more slender with the subdistal part of outer margin morerounded and curved in G. noduliferum [Figs. 4D, E, H, I,
6D–F]); the dorsal distal section of the G1 just before thechitinous part is more strongly developed (Figs. 6G, H, 7B, C)(versus G1 dorsal section is proportionately more slender in
G. noduliferum [Figs. 4D, E, H, I, 6D–F]); the chitinous distal
part is bent at a slightly greater angle from the longitudinal
axis at 45° (Fig. 6G, H) (versus chitinous distal part bent
at 40° angle in G. noduliferum [Fig. 6D–F]); and the tip ofthe chitinous part of the G1 is more acute in lateral view
(Figs. 6G, H, 7B, C) (versus tip of G1 is more rounded in
G. noduliferum [Figs. 4D, E, H, I, 6D–F]). The male pleon

For the third group of species whose members have a large
number of tubercles on the adult male cheliped dactylus, theG1 of G. cikaniki is most similar to that of G. confertum
except that the G1 is relatively more slender and the chitinous
distal part is more slender in mesial view (Fig. 21B, C)(versus G1 proportionately stouter with the chitinous distal
part wider in mesial view in G. confertum; cf. Fig. 15A,
C). In any case, G. confertum is known only from Cibodas(Gunung Gede), a separate mountain range over 20 km to theeast of Mounts Salak and Halimun. Geosesarma sekop caneasily be distinguished from G. confertum and G. cikaniki by
its proportionately longer and more slender ambulatory meri
(Fig. 16A versus Figs. 13A, 19A). While the G1 structureof G. sekop is superficially similar to G. cikaniki, it is less
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curved, with the chitinous part is relatively longer and bent
at only about 30° along the longitudinal axis (Fig. 18B, C, H,I) (versus G1 proportionately shorter with the chitinous partshorter and bent at about 40° in G. cikaniki; Fig. 21B, C).

3. Dorsal margin of dactylus of male chela with 6 or 7 large
tubercles (Fig. 22F–H); G1 very short, stout with short, roundedchitinous distal part (Fig. 23B–F) [Malang Regency, EastJava] ................................................. G. rouxi (Serène, 1968a)– Dorsal margin of dactylus of male chela with 7–19 small
tubercles along almost entire length; G1 slender, chitinous
distal part long, slender to spatulate........................................4
4. Dorsal margin of dactylus of male chela with 7–13 small
tubercles (including small one near tip) along almost entire
length; species living from lowlands to about 700 m asl.......5– Dorsal margin of dactylus of male chela with 15–19 small
tubercles (including small one near tip) along almost entire
length; montane species, from 900 m asl and above..............9
5. Carapace in life distinctly with anterior and posterior halvesdifferently coloured..................................................................6– In life, carapace evenly coloured grey, brown, orange or purple,
the anterior and posterior halves not distinctly separated......7
6. Anterior half of carapace purple to purplish-brown, posterior half
cream to yellowish-white (Ng et al., 2015: fig. 6A–C); dorsal
margin of dactylus of male chela with 7–9 small tubercles (Nget al., 2015: fig. 5D) [Cilacap Regency, Central Java].............
............................G. dennerle Ng, Schubart & Lukhaup, 2015
– Anterior half of carapace bright purple on anterior half, posterior
half bluish-grey (Ng & Davie, 1995: 32); dorsal margin of
dactylus of male chela with 10 or 11 small tubercles (Ng &Davie, 1995: fig. 2D, E; Ng et al., 2015: fig. 5C) [Ujung Kulon,
Lebak Regency, Banten] .......... G. bicolor Ng & Davie, 1995
7. Carapace evenly orange throughout in life (Ng et al., 2015: fig.
6D–F); dorsal margin of dactylus of male chela with with 7–9
small tubercles (Ng et al., 2015: figs. 5E) [Cilacap Regency,
Central Java]...........G. hagen Ng, Schubart & Lukhaup, 2015
– Carapace otherwise coloured in life; dorsal margin of dactylus
of male chela with 11–13 or small tubercles (last one oftenvery small) ..............................................................................8
8. Male pleon proportionately broader (Fig. 1D); G1 more slenderwith subdistal part of outer margin more rounded, curved, dorsal
section proportionately more slender; chitinous distal part bent
40° along longitudinal axis (Figs. 4D, E, H, I, 6D–F) [Bogorand Lebak Regencies; West Java and Banten].........................
............................................... G. noduliferum (De Man, 1892)– Male pleon proportionately more slender (Fig. 5D); G1 relatively
stouter, subdistal part of outer margin more angular, dorsal
distal section more strongly developed, chitinous distal part
bent 45° along longitudinal axis (Figs. 6G, H, 7B, C) [Lebak
Regency; Banten]................................... G. lebak, new species
9. Ambulatory meri proportionately longer and more slender(Fig. 16A); G1 with chitinous part relatively longer, gently
bent 30° along longitudinal axis (Fig. 18B, C, H, I) [Bogor
and Sukabumi Regencies; West Java].......................................
................................................................G. sekop, new species– Ambulatory meri proportionately shorter and stouter; G1 withchitinous part relatively shorter, bent 40° along longitudinalaxis..........................................................................................10
10. Margin of frontal lobe distinctly convex (Fig. 13B); G1
proportionately stouter, chitinous distal part wider in mesial
view (Fig. 15B, C) [Cibodas, Cianjur Regency, West Java]....
..................................................G. confertum (Ortmann, 1894)– Margin of frontal lobe gently convex to almost truncate (Figs.
19B, 20A); G1 relatively more slender, chitinous distal partmore slender in mesial view (Fig. 21B, C) [Mount Halimun,
Bogor Regency, West Java]............... G. cikaniki, new species

The presence of comb-like setae on the ventral margins of
the dactylus and propodus of the adult male first ambulatoryleg in some species is an interesting character. Females andjuveniles lack this feature. In G. noduliferum and G. lebak,
the ventral surfaces only have scattered stiff setae and the
comb-like setae (Fig. 13D) are never present. It is alsoabsent in G. bicolor (unpublished data). It is distinct in G.
sukabumi, G. robustum, G. confertum, G. cikaniki, and G.
rouxi. In G. sekop, the males do not have the comb-like setae,
but it is possible they are all still subadult; smaller malesof G. cikaniki examined also lack the comb-like setae andit is possible the discovery of larger males will show thischaracter is present. The function of these setae is not known
but is a useful feature to separate adults of these species.
The distribution of the seven species occurring in andaround Mount Halimun Salak National Park are distinct
and reflect the taxonomic groups they belong to (Fig. 24),with species occurring in the same area always belonging todifferent groups. For the first group, G. noduliferum occurs
east of Mount Halimun Salak, in the Bogor and Cianjur
Regencies, while G. lebak is found 30 km to the west of
the mountain range in the Lebak Regency. For the second
group, G. sukabumi is found south of Mount Halimun Salak
whereas G. robustum is found 30 km to the northeast, nearer
Bogor. The three montane species in the third group occur inhabitats from above 900 m asl, with G. confertum occurring
in Tjibodas, G. sekop living on Mount Salak to the east of
the national park whereas the closely allied G. cikaniki ispresent 20 km to the west on the top of Mount Halimun.
With regards to the conservation status for the five new
species, all occur in a nationally protected area and arethus not faced by any immediate threats. In any case, mostGeosesarma species have not been subjected to a moredetailed conservation assessment as has been done for the
primary crabs (cf. Cumberlidge et al., 2009). This should
be done eventually considering their similar habits and highdegree of endemicity.
Key to Species of Javan Geosesarma
1. Dorsal margin of dactylus of male chela with 3 or 4 tubercles;
G1 relatively stout....................................................................2– Dorsal margin of dactylus of male chela with more than 5
tubercles; G1 relatively slender...............................................3
2. Male pleon with somite 6 trapezoidal (Fig. 11D, E); G1
proportionately very stout, wide, chitinous part very short,bent about 45° along longitudinal axis (Fig. 12B–F) [Bogor
Regency, West Java]........................G. robustum, new species– Male pleon with somite 6 subrectangular (Fig. 8D, E); G1
proportionately less stout, more narrow, chitinous distal part
relatively elongate, bent about 80° along longitudinal axis (Fig.
10B–D) [Sukabumi Regency, West Java].................................
......................................................... G. sukabumi, new species245

Ng & Wowor: New Geosesarma crabs from JavaACKNOWLEDGEMENTS

Ng PKL & Davie PJF (1995) The terrestrial sesarmine crabs of thegenera Metasesarma and Geosesarma (Crustacea: Decapoda:
Brachyura: Grapsidae) of Ujung Kulon, West Jawa, Indonesia.
Tropical Biodiversity, 3: 29–43.
Ng PKL, Guinot D & Davie PJF (2008) Systema Brachyurorum:
Part I. An annotated checklist of extant brachyuran crabs of
the world. Raffles Bulletin of Zoology, Supplement 17: 1–286.
Ng PKL, Schubart CD & Lukhaup C (2015) New species of“vampire crabs” (Geosesarma De Man, 1892) from central Java,
Indonesia, and the identity of Sesarma (Geosesarma) nodulifera
De Man, 1892 (Crustacea, Brachyura, Thoracotremata,Sesarmidae). Raffles Bulletin of Zoology, 63: 3–13.
Ng PKL & Tan CGS (1995) Geosesarma notophorum sp. nov.
(Decapoda, Brachyura, Grapsidae, Sesarminae), a terrestrial
crab from Sumatra, with novel brooding behaviour. Crustaceana,
68(3): 390–395.
Ng PKL & Wowor D (2018) A new genus and new species of a semiterrestrial freshwater crab from montane tropical rainforests
in Java, Indonesia (Decapoda: Brachyura: Gecarcinucidae).
Journal of Crustacean Biology, 38(3): 341–348.
Nobili G (1900) Decapodi e Stomatopodi Indo-Malesi. Annali delMuseo Civico di Storia Naturale di Genova, Genova, Series 2,20(40): 473–523, figs. 1–4.
Ortmann AE (1894) Crustaceen. In: Semon R (ed.) Zoologische
Forschungreisen in Australien und dem Malayischen Archipel
in den Jahren 1891–93. V. Denkschriften der MedizinischNaturwissenschaftlichen Geselschaft, Jena, 8. Pp. 1–80, pls. 1–3.
Rathbun MJ (1910) Decapod crustaceans collected in Dutch East
India and elsewhere by Mr. Thomas Barbour in 1906–1907.
Bulletin of the Museum of Comparative Zoölogy, 52(16):305–317.
Roux J (1933) Crustacés Décapodes d’eau douce. In: Résultats
Scientifiques du Voyage aux Indes Orientales Néerlandaisesde LL. AA. RR. le Prince et la Princesse Léopold de Belgique.
Memoires du Musée Royal d’Histoire Naturelle de Belgique,Hors Série [= Supplement] 3, No. 14 [= 3(14)]. Pp. 1–18,
figs. 1, 2.
Serène R (1968a) Note préliminaire sur de nouvelles especes deSesarma (Decapoda Brachyura). Bulletin du Muséum naturelled’Histoire National, Paris, (2)39(5): 1084–1095, pls. 1, 2.
Serène R (1968b) The Brachyura of the Indo Pacific Region. In:
Tixier-Durivault A & Serène R (eds.) Prodromus for a Check
List of the Non-planctonic Marine Fauna of South East Asia.
Special Publication of the Singapore National Academy of
Science, No. 1. Pp. 33–120.
Serène R & Soh CL (1970) New Indo-Pacific Genera allied to
Sesarma Say 1817 (Brachyura, Decapoda, Crustacea). Treubia,
27(4): 387–416, pls. 1–8.
Soh CL (1969) Abbreviated development of a non-marine crab,
Sesarma (Geosesarma) perracae (Brachyura; Grapsidae) fromSingapore. Journal of Zoology, 158: 357–370.
Tesch JJ (1917) Synopsis of the genera Sesarma, Metasesarma,
Sarmatium and Clistocoeloma, with a key to the determinationof the Indo-Pacific species. Zoologische Mededeelingen, 3(2–3):
127–260, figs. 1–8, pls. 15–17.
Wowor D & Ng PKL (2018) A new sesarmid crab of the genus
Karstarma (Crustacea: Decapoda: Brachyura) associatedwith limestone formations in East Java, Indonesia. Zootaxa,
4482(2): 355–366.

The second author especially grateful to Witjaksono, theHead of Research Center for Biology LIPI; the late Tri
Siswo Rahardjo MSi, the head of Taman Nasional Gunung
Halimun Salak, Ministry of Environment and Forestry;Thomas von Rintelen, Museum für Naturkunde Berlin;
Ristiyanti M. Marwoto, Renny K. Hadiaty, Ujang Nurhaman
and Sopian Sauri for solid field work collaboration andcompanionship; special thanks to Ujang and Sopian foralways helping the second author in the field and having goodeyes for crustaceans. Thanks are also due to Tohru Narusefor his critical reading of the manuscript and many usefulsuggestions. This work was supported by the joint IndonesiaGerman Indobiosys project, i.e. by Indonesian DIPA
(079.01.2.017148 2015, project number 3400.003.050.I; and079.01.2.017148 2016, project number 3400.010.005.061B)
and BMBF (INDOBIOSYS MfN Berlin, 16GW0111K).
LITERATURE CITED
Cumberlidge N, Ng PKL, Yeo DCJ, Magalhães C, Campos MR,
Alvarez F, Naruse T, Daniels SR, Esser LJ, Attipoe FYK,
Clotilde-Ba F-L, Darwall W, Mcivor A, Collen B & Ram M(2009) Freshwater crabs and the biodiversity crisis: importance,
threats, status, and conservation challenges. BiologicalConservation, 142: 1665–1673.
Dana JD (1851) Conspectus Crustaceorum quæ in Orbis Terrarum
circumnavigatione, Carolo Wilkes e Classe Reipublicæ
Foederatæ Duce, lexit et descripsit. Proceedings of the Academyof Natural Sciences of Philadelphia, 5: 247–254.
Davie PJF, Guinot D & Ng PKL (2015) Anatomy and functional
morphology of Brachyura. In: Castro P, Davie PJF, Guinot D,
Schram FR, von Vaupel Klein JC (eds.) Treatise on Zoology –Anatomy, Taxonomy, Biology. The Crustacea. Volume 9C-I.
Decapoda: Brachyura (Part 1). Pp. 11–163.
Davie PJF & Ng PKL (2007) A new genus for cave-dwelling crabs
previously assigned to Sesarmoides (Crustacea: Decapoda:
Brachyura: Sesarmidae). Raffles Bulletin of Zoology,
Supplement 16: 227–231.
De Man JG (1892) Decapoden des Indischen Archipels. In: Weber
M (ed.), Zoologische Ergebnisse einer Reise in Niederlandisch
OstIndien, 2. Pp. 265–527, pls. 15–29.
De Man JG (1902) Die von Herrn Professor Kükenthal im
indischen Archipel gesammelten Dekapoden und Stomatopoden.
In: Kükenthal W (ed.) Ergebnisse einer zoologischen
Forschungsreise in den Molukken und Borneo, in Aufträge
der Senckenberg. Naturforsch. Gesellschaft ausgeführt von
Dr. Willy Kükenthal. Abhandlungen der Senckenbergischen
naturforschenden Gesellschaft, 25(3). Pp. 467–929, pls. 19–27.
Ng PKL (1988) The Freshwater Crabs of Peninsular Malaysia andSingapore. Department of Zoology, National University ofSingapore, Shinglee Press, Singapore, pp. i–viii, 1–156, figs.
1–63, 4 colour pls.
Ng PKL (2017) On the identities of the highland vampire crabs,
Geosesarma foxi (Kemp, 1918) and G. serenei Ng, 1986,
with description of a new phytotelmic species from Penang,
Peninsular Malaysia (Crustacea: Decapoda: Brachyura:
Sesarmidae). Raffles Bulletin of Zoology, 65: 226–242.

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