RAFFLES BULLETIN OF ZOOLOGY 2020
Taxonomy & Systematics
RAFFLES BULLETIN OF ZOOLOGY 68: 267–307

Date of publication: 29 April 2020
DOI: 10.26107/RBZ-2020-0023
http://zoobank.org/urn:lsid:zoobank.org:pub:057B08EE-1006-43E8-AE20-0AF8F224BA2D

A revision of the deep-sea porter crabs of the genus Gordonopsis
Guinot & Richer de Forges, 1995 (Crustacea, Decapoda, Brachyura,
Homolidae), with descriptions of five new speciesPeter K. L. Ng1* & Bertrand Richer de Forges2
Abstract. For the century to 2018, only one species of the deep-water porter crab Gordonopsis Guinot & Richer
de Forges, 1995 (Brachyura, Homolidae), the type species, G. profundorum (Alcock & Anderson, 1899), was
known, and only from a handful of specimens from the Indian Ocean. In 2019, two species were described fromthe eastern Indian and western Pacific Oceans. The present revision of available material, most of which was only
collected in the last decade, adds five new species to the genus. This explosion in species numbers demonstrates
just how poor our understanding is of deep-sea habitats and their constituent fauna.
Key words. taxonomy, world revision, Homoloidea, new species, rarity

INTRODUCTION

Gordonopsis. The poorly known Gordonopsis profundorums. str. is rediagnosed based on a neotype selection. Five
species of Gordonopsis from the Indian and Pacific Oceans
are here described as new: G. alaini (Madagascar), G. hera
(Papua New Guinea), G. velutina (Admiralty Islands), G.
phorcys (Solomon Islands), and G. ceto (South China Sea).

The many deep-sea surveys in the Indo-West Pacificbetween 1986 and 2013 by French vessels have collectedlarge numbers of porter crabs of the family Homolidae De
Haan, 1839 (see Guinot & Richer de Forges, 1995; Richer deForges & Ng, 2007, 2008, 2020; Naruse & Richer de Forges,
2010; Richer de Forges et al., 2013; Ng & Richer de Forges,2017), and numerous new taxa have been reported over theyears. One genus, however, that has remained relatively
unchanged is Gordonopsis Guinot & Richer de Forges, 1995,
established for one species, Homola profundorum Alcock& Anderson, 1899, from the Indian Ocean and known only
from a handful of specimens.

MATERIAL AND METHODS
The abbreviations G1 and G2 are used for male first andsecond gonopods, respectively. The terminology follows
Guinot & Richer de Forges (1995), Guinot & Bouchard(1998), and Davie et al. (2015). Measurements provided (inmillimetres) are of the maximum carapace width and length(including spines and rostrum), respectively. The term spine
is used when the structure is prominent and long; whensmall (e.g., resembling a sharp and elongate granule), theterm spinule is used instead.

Over the last five years, various French and other expeditions
have collected a number of specimens of Gordonopsis fromboth the Indian and Pacific Oceans. The authors have been
progressively examining these as well as old material in an
attempt to revise the genus, but this work was constrained bytheir inability to find the type specimens. Recently, Ng et al.
(2019) described a new species, G. robusta, from the eastern
Indian Ocean, while Takeda & Suyama (2019) described G.
pacifica, from southernmost Japan. The present study revises

The material examined is deposited in the Muséum
National d’Histoire Naturelle, Paris, France (MNHN);
The Natural History Museum, London, U.K. (NHM);
Museum für Naturkunde, Berlin, Germany (ZMB); Centre
for Marine Living Resources and Ecology, Kochi, Kerala,
India (CMLRE); National Science Museum, Tokyo, Japan(NSMT); Crustacean Collections of the National Taiwan
Ocean University, Taiwan (NTOU); and the Zoological
Reference Collection, Lee Kong Chian Natural History
Museum, National University of Singapore (ZRC).

Accepted by: Jose Christopher E. Mendoza
1
Lee Kong Chian Natural History Museum, National University of Singapore, 2Conservatory Drive, Singapore 117377, Republic of Singapore; Email: peterng@
nus.edu.sg (*corresponding author)

Muséum National d’Histoire Naturelle, Institut de Systématique, Évolution,
Biodiversité, ISYEB - UMR 7205 – CNRS, MNHN, UPMC, EPHE, Département
Systématique et Evolution, 57 rue Cuvier, CP26, 75005 Paris, France; Email:b.richerdeforges@gmail.com

2© National University of Singapore
ISSN 2345-7600 (electronic) | ISSN 0217-2445 (print)267

Ng & Richer de Forges: Revision of Gordonopsis
SYSTEMATICS

Guinot & Richer de Forges (1981: 536) later examined amale 15.4 × 10.0 mm from Madagascar.

Family Homolidae De Haan, 1839

Guinot & Richer de Forges (1995) studied the material from
the Maldives and Madagascar as well as one broken specimen
from the Seychelles and observed differences between thedescription of G. profundorum as described and figured by
Alcock & Anderson (1899) and Alcock (1901). As such,they were uncertain if all the specimens were conspecific.
The Seychelles specimen was too damaged to be useful.
Guinot & Richer de Forges (1995) identified their material
as “Gordonopsis aff. profundorum”, particularly for the
specimen from the Maldives, which according to them, hada more bulging carapace as well the possession of a distinct
short spine on the latero-posterior part of the carapace, justbehind the branchio-hepatic groove (Fig. 2B). The specimen
from Madagascar (Fig. 9B) agrees with the type description
and figures of G. profundorum in possessing a short spineon the latero-posterior part of the carapace (Fig. 9B). Alcock& Anderson (1899: 10, pl. 1 fig. 2) noted that there wasa “blunt denticle near the middle of the ill-defined lateralborder” of the carapace and their figures actually show this(Fig. 1B). The excellent figure of the East African specimen
by Doflein (1904) also shows a latero-posterior tubercle on
the carapace (Fig. 6B). The specimen from the Maldives
has the lateral sides of the carapace slightly more bulging,
giving the carapace a less pyriform and more ovate shapeand the latero-posterior carapace tubercle is a distinct shortspine (Fig. 2B). Guinot & Richer de Forges (1995: 467)
also commented that the ambulatory legs of the specimensfrom Madagascar and Maldives appeared to be longer andslenderer than the Indian ones, but the accuracy of Alcock’s(1901) figures cannot be ascertained.

Gordonopsis Guinot & Richer de Forges, 1995
Type species. Homola profundorum Alcock & Anderson,
1899, by original designation and monotypy.
Diagnosis. Carapace longitudinally ovate to subpyriform,
anterior half of carapace narrower than posterior half; dorsal
surface not ornamented but with scattered to dense setae;
gastric fossa distinct; cervical groove pronounced; homolianline (linea homolica) on each side prominent; subhepatic
region gently convex but not swollen, with short spine;
rostral spine long, thick, pseudorostral spines well developed,
directed anterolaterally; no teeth or latero-anterior spines,
gastric and cardiac regions gently convex; latero-posterioredge with low prominence or distinct tooth or spine; orbit
absent; ocular peduncle short, stout; infra-orbital spine absent;
acute antennal spine, visible dorsally; antennal articles 2
and 3 very wide, with strong external distal spine, article
4 relatively short, broad; proepistome weakly developed;
epistome very reduced; third maxilliped pediform, narrow,covering only part of buccal frame, anterior margin of merus
exceeding endostomial crest; chelipeds not prominently
elongate, fingers relatively long, thin, without pigmented
spot at base of pollex; P2–P4 relatively long; merus long,
dorsal margins armed with spines, ventral margin with shortspines or unarmed; proximal part of outer surface of P4 may
have tubercle or short spine on outer surface or unarmed;
P5 short, total length less than length of P4 merus; merus
slender, unarmed on all surfaces, reaching to gastric groove
or mesogastric region on the carapace above gastric fossae,
propodus and dactylus subchelate, occluding margins withlong spines; male pleon locked between coxae of P1–P4:
spinule present on inner margin of each coxa of P1–P3 that
locks pleon to appress it to sternum; anterior tip of telson
positioned between basis and coxa of third maxillipeds;
lock present as “homolid press button” mechanism (sternal
prominence on outer edge of sternite 4 above articular condyleof P1 coxa, socket in inner surface of pleonal somite 6);
male and female pleon with 6 free somites and telson; G1
stout, short with distal part tapering; G2 short, as long as
G1, distal part spatuliform. (Modified from Guinot & Richer
de Forges, 1995: 463)

The uncertainty over the identity of G. profundorum has
been a major problem, and a revision of the genus is only
possible once this has been resolved. In this revision, we
select a neotype for the species (see discussion for typespecies below). We also rediagnose G. robusta and G.
pacifica based on the type material and describe five new
species from Madagascar, Papua New Guinea, Admiralty
Islands, Solomon Islands, and the South China Sea.
Gordonopsis profundarum (Alcock & Anderson, 1899)(Figs. 1–8)
Homola profundorum Alcock & Anderson, 1899: 5; Alcock, 1899:10, pl. 1 fig. 2.
Homola (Paromola) profundorum – Alcock, 1901: 64, pl. 5 fig.
22; Doflein, 1904: 16, pl. 7 figs. 1, 2.
Paromola profundorum – Ihle, 1913: 57; Serène & Lohavanijaya,
1973: 27.
Paromola profundarum – Gordon, 1950: 223; Griffin, 1965: 87.
Gordonopsis profundorum – Guinot & Richer de Forges, 1995:
463, figs. 63d–h, 64A, B.
Gordonopsis aff. profundorum – Guinot & Richer de Forges,
1995: 467 (in part).
Gordonopsis profundorum – Ng et al., 2008: 40.

Remarks. Gordonopsis Guinot & Richer de Forges,
1995, was established for a rare species formerly placedin Paromola Wood-Mason in Wood-Mason & Alcock,1891 (Alcock, 1901; Doflein, 1904; Ihle, 1913). Only one
species was known at that time, G. profundorum (Alcock& Anderson, 1899), described from three young female
specimens (ca. 13.0 × 9.0 mm) collected in the western
Indian Ocean off the Travancore coast, India (7°17′30″N,
76°54′30″E) at a depth of 796 m (Alcock & Anderson, 1899:
5; Alcock, 1901: 65) (Fig. 1). The species was subsequently
reported from the east coast of Africa by Doflein (1904: 16)from a male 24 mm in carapace length, with Gordon (1950:
220) recording a male 16.0 × 11.0 mm from the Maldives.

Material examined. Neotype: male (11.0 × 16.0 mm)(here designated) (NHM 1948.9.7.28), stn 153, 4°42′36″N,
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Fig. 1. Gordonopsis profundarum (Alcock & Anderson, 1899), syntype female (ca. 13.0 × 9.0 mm), Travancore, India. A, overall habitus;B, dorsal view of carapace; C, frontal view of cephalothorax showing buccal cavity, epistome, antennae, antennules, and third maxillipeds.
After Alcock (1901: pl. 5 fig. 22).

72°50′24″E – 4°45′36″N, 72°52′12″E, Maldives, 256–293
m, dredge, coll. John Murray Expedition, 4 April 1934. – 1
male (16.3 × 24.1 mm) (ZMB 13645), stn 258, 2°58.5′N,
46°50.8′E, off Somalia, East Africa, 1,362 m, coll. Deutsche
Tiefsee Expedition, coll. Valdivia, 1898–1899.

discernible orbit (Figs. 1B, 2B, 6B). Hepatic region gently
inflated, with short obliquely directed spine (Figs. 1B, 2B,
6B). Gastric region without spines (Figs. 1B, 2B, 6B). Gastricgroove well marked, with distinct ovate gastric fossae justabove (Figs. 1B, 2B, 6B). Cardiac region swollen; branchialregion inflated, with distinct branchio-cardiac grooves (Figs.
1B, 2B, 6B). Latero-posterior tubercle on carapace large,
prominent, sharp (Figs. 1B, 2B, 6B). Base of antenna withstrong spine (Figs. 1C, 3D, 7D). Antennal flagellum short,second and third articles thick, setose. Epistome triangular(Figs. 1C, 3D, 7D). Third maxilliped pediform, merus
elongate with angular external angle (Figs. 1C, 3C, 7C).
Chelipeds long; fingers long, about half length of palm;surface gently rugose with scattered small granules; carpus
longitudinally ovate, outer margin with 3 spines and 2 or 3
spinules, distal edge with 1 spine, inner margin with 2 or
3 spines and 2 or 3 spinules, dorsal surface with low ridge
lined with 6–9 low or sharp granules, never spines; merus
triangular in cross-section, relatively long, curved, dorsal
margin with 5 or 6 spines and distal 2 spines bracketing

Diagnosis. Male: carapace longitudinally ovate, width tolength ratio 0.68–0.69, distinctly wider posteriorly thananteriorly; dorsal carapace surface with well-defined
regions, separated by broad, deep grooves; lateral margin
distinctly convex; dorsal parts with numerous scattered soft
setae, not obscuring surface; lateral parts with denser setae,
partially obscuring surface, relatively denser on hepatic,
pterygostomial, and suborbital regions (Figs. 1A–C, 2A–C,
3A, B, 6A–C, 7A, B). Rostrum relatively long, sharp, with 2
long, obliquely directed pseudorostral spines, just shorter thanrostrum (Figs. 1B, 2B, 6B). Supraorbital margin relatively
narrow, C-shaped; pseudorostral spines directed obliquely
laterally at angle of about 45° to median axis (Figs. 1B, 2B,
6B). Eyes with short ocular peduncle, cornea prominent; no269

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Fig. 2. Gordonopsis profundarum (Alcock & Anderson, 1899), neotype male (16.0 × 11.0 mm) (NHM 1948.9.7.28), Maldives. A, overall
habitus; B, dorsal view of carapace; C, dorso-frontal view of carapace.

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Fig. 3. Gordonopsis profundarum (Alcock & Anderson, 1899), neotype male (16.0 × 11.0 mm) (NHM 1948.9.7.28), Maldives. A, lateralview of cephalothorax; B, frontal view of cephalothorax; C, left third maxilliped; D, ventral view showing buccal cavity, epistome,
antennae, and antennules; E, outer view of merus and carpus of left cheliped; F, dorsal view of left merus, carpus, and chela; G, dorsal
view of right carpus and chela; H, outer view of right chela; I, outer view of left chela.

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Fig. 4. Gordonopsis profundarum (Alcock & Anderson, 1899), neotype male (16.0 × 11.0 mm) (NHM 1948.9.7.28), Maldives. A, dorsal
view of carapace showing relative P5 length; B, pleon; C, telson and pleonal somite 6; D, posterior part of carapace and pleon; E,
sternopleonal cavity; F, right P2–P4 coxae and basis-ischia (denuded); G, left P2–P4 coxae and basis-ischia (denuded); H, ventral viewof left G1; I, ventral view of left G2.

chela, outer ventral margin with 7–9 spines or spinules,
inner ventral margin with 5 or 6 spines or spinules (Figs.
1A, 2A, 3E–I, 6A, 7E–G). Ambulatory legs long; basisischium with small granules, not spines; P2 merus with5 spines or spinules on dorsal margin (excluding 1 distal
spine), ventral and subventral margins with 1–4 spinules;
P3 merus with 5 or 6 spines or spinules on dorsal margin(excluding 1 distal spine), ventral and subventral margins
with 0–3 spinules; P4 merus with 3 or 4 spines or spinules
on dorsal margin (excluding 1 distal spine), ventral margin
with 1 spine or spinule, outer surface with 1 strong proximal
spine or spinule (Figs. 1A, 2A, 5A–C, 6A, 8F–H). P5 merus
slender, unarmed on all margins, reaching beyond gastricgroove when folded anteriorly; carpus long, propodus short,enlarged, forming prominent pseudochela with stout, gently
curved dactylus; occlusal margin of fixed finger with 7–9
spines, that of dactylus with 7 or 8 spines (Figs. 4A, 5D–F,
8A, I, J). Outer margins of P2–P4 coxae smooth, unarmed(Figs. 4E–G, 8D, E). Telson triangular, with convex lateral
margins, distal part distinctly narrowing (Figs. 4B–D, 8B,
C). G1 short, stout, distal part subconical with convex tip(Figs. 4H, 8K). G2 stout, tubular, subequal to G1 length,
distal portion cup-shaped (Figs. 4I, 8L).
Description of male neotype. Male: carapace longitudinallyovate, width to length ratio 0.69, distinctly wider posteriorly
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Fig. 5. Gordonopsis profundarum (Alcock & Anderson, 1899), neotype male (16.0 × 11.0 mm) (NHM 1948.9.7.28), Maldives. A–D, rightP2–P5, respectively (all to same scale); E, right P5 pseudochela; F, left P5 pseudochela.

than anteriorly; dorsal carapace surface with well-defined
regions, separated by broad, deep grooves; lateral margin
distinctly convex; dorsal parts with numerous scattered soft
setae, not obscuring surface; lateral parts with denser setae,
partially obscuring surface, relatively denser on hepatic,
pterygostomial, and suborbital regions (Figs. 1A–C, 2A–C,
3A, B, 6A–C, 7A, B). Rostrum relatively long, sharp, with
2 long, obliquely directed pseudorostral spines, shorter thanrostrum (Figs. 1B, 2B, 6B). Supraorbital margin relatively
narrow, C-shaped; pseudorostral spines directed anterolaterally at angle of about 45° to median axis (Figs. 1B, 2B,
6B). Eyes with short ocular peduncle, cornea prominent; nodiscernible orbit (Figs. 1B, 2B, 6B). Hepatic region gently

inflated, with short obliquely directed spine (Figs. 1B, 2B, 6B).
Gastric region without spines, each mesogastric region withmedian patch of small granules (Figs. 1B, 2B, 6B). Gastricgroove well marked, with distinct ovate gastric fossae justabove (Figs. 1B, 2B, 6B). Cardiac region swollen; branchialregion inflated, with distinct branchio-cardiac grooves (Figs.
1B, 2B, 6B). Latero-posterior tubercle on carapace distinct,
prominent (Figs. 1B, 2B, 6B). Base of antenna with strong
spine (Figs. 1C, 3D, 7D). Antennal flagellum short, second
and third articles thick, setose. Epistome triangular (Figs.
1C, 3D, 7D). Third maxilliped pediform, merus elongate
with angular external angle (Figs. 1C, 3C, 7C). Chelipeds
long; fingers long, about half length of palm; surface gently273

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Fig. 6. Gordonopsis profundarum (Alcock & Anderson, 1899), male (16.3 × 24.1 mm) (ZMB 13645), East Africa. A, overall habitus; B,
dorsal view of carapace; C, dorso-frontal view of carapace.

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Fig. 7. Gordonopsis profundarum (Alcock & Anderson, 1899), male (16.3 × 24.1 mm) (ZMB 13645), East Africa. A, lateral view of
cephalothorax; B, frontal view of cephalothorax; C, left third maxilliped; D, ventral view showing buccal cavity, epistome, antennae, andantennules; E, outer view of merus and carpus of left cheliped; F, outer view of left carpus and chela; G, dorsal view of left cheliped.

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Fig. 8. Gordonopsis profundarum (Alcock & Anderson, 1899), male (16.3 × 24.1 mm) (ZMB 13645), East Africa. A, dorsal view ofcarapace showing relative P5 length; B, pleon; C, telson and pleonal somite 6; D, right P2–P4 coxae and basis-ischia (denuded); E, left
P2–P4 coxae and basis-ischia (denuded); F–I, right P2–P5, respectively (all to same scale); J, right P5 pseudochela; K, ventral view ofleft G1; L, ventral view of left G2.

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rugose with scattered small granules; carpus longitudinallyovate, outer margin with 3 spines and 2 spinules, distal edge
with 1 spine, inner margin with 2 spines and 3 spinules,
dorsal surface with low, uneven ridge lined with 6–8 very
low granules; merus triangular in cross-section, relatively
long, curved, dorsal margin with 4 spines and 2 spinules,
with distal 2 spines bracketing chela, outer ventral margin
with 8 or 9 spines or spinules, inner ventral margin with
6 spinules (Figs. 1A, 2A, 3E–I, 6A, 7E–G); basis-ischium
quadrate, outer margin with 2 spinules, inner margin with 3
spinules, dorsal margin with prominent spine. Ambulatory
legs long; basis-ischium with 4 small granules (sometimes
very small and almost undiscernible), never with spines; P2
merus with 5 spines or spinules on dorsal margin (excluding
1 distal spine), subventral margin with 4 spinules; P3 merus
with 5 spines or spinules on dorsal margin (excluding 1
distal spine), subventral margin with 3 spinules; P4 merus
with 3 spines on dorsal margin (excluding 1 distal spine),
ventral margin with 1 spinule, outer surface with 1 strong
proximal spinule (Figs. 1A, 2A, 5A–C, 6A, 8F–H). P5 merus
slender, unarmed on all margins, reaching beyond gastricgroove when folded anteriorly; carpus long, propodus short,enlarged, forming prominent pseudochela with stout, gently
curved dactylus; occlusal margin of fixed finger with 7 spines,that of dactylus with 7 or 8 spines (Figs. 4A, 5D–F, 8A, I,
J). Outer margins of P2–P4 coxae smooth, unarmed (Figs.
4E–G, 8D, E). Telson triangular, with gently convex lateral
margins, distal part distinctly narrowing (Figs. 4B–D, 8B,
C). G1 short, stout, distal part subconical with gently convex
tip (Figs. 4H, 8K). G2 stout, tubular, subequal to G1 length,
distal portion cup-shaped (Figs. 4I, 8L).

the original description and figures agree very well withthe two males examined in this study from the Maldivesand East Africa. While the armature on the meri of P2–P4of the type figure agree with the present specimens, themeri and propodi are significantly shorter (Fig. 1A). This
discrepancy in proportions cannot be explained by size
alone even though the syntypes are smaller in size than thepresent material. Specimens of other species in which large
and small specimens are known (e.g., G. robusta, Fig. 12)
do not show such a substantial difference in proportions. We
tried to examine the type material of G. profundarum, allsupposedly still in the present Zoological Survey of India(Calcutta) but the material could not be located despite several
searches over two years (S. Mitra, personal communication).
They are also not in the NHM. The syntypes are thus almost
certainly lost.
The only species that has ambulatory meri as short as those
figured by Alcock (1899, 1901) (present Fig. 1A) is G. robusta
from the Andamans in the eastern Indian Ocean (Figs. 12A,
B, 13G, H); but in this species, the carapace and P2–P5 areprominently more setose (Fig. 12A–D) (versus less setosein G. profundarum; Figs. 1A–C, 6A–C); the surfaces of thechela are prominently granulated (Fig. 12E) (versus smooth in
G. profundarum; Figs. 3H, I, 7F); the carpus of the cheliped
has more spines (Fig. 13F) (versus carpus less prominently
spinose in G. profundarum; Figs. 3F, G, 7F, G); the lateral
margins of the male telson are uniformly convex (Fig. 13D)(versus with the proximal part convex but tapering more
sharply to the tip in G. profundarum; Figs. 4B, 8C); andthe distal part of the G1 is more elongate with a bifurcatetip (Fig. 13K) (versus the distal part being shorter with aconvex tip in G. profundarum; Figs. 4H, 8K).

Variation. The latero-posterior carapace tubercles do notappear to vary—both the small female from Maldives andthe large East African specimens have similarly sized large
ones (Figs. 2B, 6B); and both have the same carapace shape
as well as long ambulatory legs of similar proportions.

Remarks. Alcock & Anderson (1899) named the species“Homola profundorum” and also used this spelling in anotherpaper (Alcock, 1901). Gordon (1950) used the spelling“profundarum” for the species but she did not explain why,
and other authors have continued to use “profundorum”(cf. Ihle, 1918; Guinot & Richer de Forges, 1995; Ng etal., 2008). If the gender of the genus name is masculine or
neuter, the species name should be spelled, “profundorum”.
Gordonopsis, however, is feminine (all names ending in-opsis are feminine under Article 30.1.2 of the zoologicalcode; ICZN, 1999) and so, the correct spelling for the speciesname is “profundarum”.

As discussed earlier, the specimens here, referring to G.
profundarum s. str. from the Maldives and East Africa,differ from those figured by Alcock (1899, 1901) (present
Fig. 1A) only in possessing proportionately longer P2–P5.
We are of the opinion that Alcock’s (1899, 1901) figures of
the P2–P4 are inaccurate, with the legs probably originallydrawn at an angle. In view of the uncertainty of the identityof what is G. profundarum s. str., the loss of the types, andthat it is the type species of the genus, there is now a clear
need to designate a neotype for the species. To stabilise
the taxonomy of the species and genus, we here select amale (11.0 × 16.0 mm, NHM 1948.9.7.28) as the neotypeof Homola profundorum Alcock & Anderson, 1899. This
specimen was collected from the Maldives at 4°42′36″N,
72°50′24″E – 4°45′36″N, 72°52′12″E (cf. Sewell, 1935), asite approximately 500 km southwest of the type localityof the original H. profundorum off Travancore. Both sites
are in the same basin.

Alcock & Anderson (1899: 5) described the species on
the basis of three young females (size given as about
13.0 × 9.0 mm) collected by the “Investigator” from theTravancore coast (7°17′30″N, 76°54′30″E), from a depthof 430 fathoms (= 796 m). One of these syntype specimens
was figured by Alcock (1899: 10, pl. 1 fig. 2; 1901: 64, pl.
5 fig. 22). In the structure of the carapace and chelipeds,

The waters off Travancore and western Indian Ocean arehome to two species of Gordonopsis. Gordonopsis alaini, newspecies, from off Madagascar, has P2–P5 meri and propodi
proportions that agree better with those of G. profundarum
figured by Alcock (1899, 1901) (present Fig. 1A) but caneasily be distinguished by its more triangular carapace shape(Fig. 9B) (versus more ovate in G. profundarum; Figs. 2B,

Colour. Not known.

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slender, unarmed on all margins, reaching beyond gastricgroove when folded anteriorly; carpus long, propodus short,enlarged, forming prominent pseudochela with stout, gently
curved dactylus; occlusal margin of fixed finger with 5 or
6 spines, that of dactylus with 5 or 6 spines (Fig. 11H–K).
Outer margins of P2–P4 coxae smooth, unarmed (Fig. 11C).
Telson triangular, with convex lateral margins, distal part
distinctly narrowing (Fig. 11B, D). G1 short, stout, distal partprominently narrowed with subtruncate tip (Fig. 10H). G2
stout, tubular, length subequal to G1, basal portion slightly
dilated, covered with long setae, distal portion cup-shaped(Fig. 10I).

6B); the latero-posterior carapace tubercle is visible only
as a low swelling (Fig. 9B) (versus present as a distinct
tubercle in G. profundarum; Figs. 2B, 6B); the carpus of
the cheliped has fewer spines (Fig. 10E–G) (versus withnumerous spines in G. profundarum; Figs. 3F, G, 7F, G);
and the distal part of the G1 is very broad (Fig. 10H) (versus
G1 distal part narrow in G. profundarum; Figs. 4H, 8K). See
general discussion for comparisons with other congeners.
Gordonopsis alaini, new species(Figs. 9–11)
Paromola profundorum – Guinot & Richer de Forges, 1981: 536,
figs. 3A, 4F, 5A, A1, pl. 3 fig. 1, 1a.
Gordonopsis aff. profundorum – Guinot & Richer de Forges, 1995:
467, figs. 63d–h, 64A, B.
Gordonopsis profundorum – Garassino, 2009: 11, pl. 2.

Colour. Not known.
Etymology. The species is named after our good friend
Alain Crosnier, who first collected this species. Alain haschanged the face of modern carcinology through his many
decades of work, for which we are most grateful.

Material examined. Holotype: male (10.9 × 16.8 mm)(MNHN-IU-2017-9049 = MNHN B-7026), station CH38 P3
trawl 38, 12°50.0′S, 48°09.1′E, northwest coast, Madagascar,
580–585 m, coll. CREVETTIERE 1972, A. Crosnier, 14
September 1972.

Remarks. See general discussion for comparisons withcongeners.
Gordonopsis robusta Ng, Padate & Saravanane, 2019
(Figs. 12, 13)

Diagnosis. Male: carapace longitudinally pyriform, width tolength ratio 0.65, distinctly wider posteriorly than anteriorly;
dorsal carapace surface with well-defined regions, separated
by broad, deep grooves; lateral margin sinuous, almost
straight; dorsal parts with scattered soft setae, not obscuring
surface; lateral parts more setose but not obscuring surface(Figs. 9A–C, 10A, B). Rostrum relatively long, sharp, with
2 long, obliquely directed pseudorostral spines, just shorter
than rostrum (Fig. 9B). Supraorbital margin relatively narrow,
C-shaped; pseudorostral spines directed obliquely laterally atangle of about 45° (Fig. 9B). Eyes with short ocular peduncle,
cornea prominent; no discernible orbit (Fig. 9B). Hepatic
region not inflated, with short obliquely directed spine (Fig.
9B). Gastric region without spines (Fig. 9B). Gastric groove
well marked, with distinct ovate gastric fossae just above (Fig.
9B). Cardiac region swollen; branchial region inflated, with
distinct branchio-cardiac grooves (Fig. 9B). Latero-posterior
tubercle on carapace very low, barely discernible (Fig. 9B).
Base of antenna with short spine (Fig. 10D). Antennal
flagellum short, second and third articles thick, setose.
Epistome triangular (Fig. 10D). Third maxilliped pediform,
merus elongate with spiniform external angle (Fig. 10C).
Chelipeds long; fingers stouter, about two-thirds length ofpalm; surface gently rugose to smooth; carpus longitudinallyovate, outer, distal, and inner margins with 1 long spine each,dorsal surface with low ridge but unarmed; merus triangularin cross-section, relatively long, curved, dorsal margin with
7 spines and distal 2 spines bracketing chela, outer ventral
margin with 7 spines, inner ventral margin with 6 spinules(Figs. 9A, 10E–G). Ambulatory legs relatively long; basisischium with small granules, not spines; P2 merus with 3
spines on dorsal margin (excluding 1 distal spine), ventral
margin with 2 spinules; P3 merus with 3 spines on dorsal
margin (excluding 1 distal spine), ventral margin unarmed;
P4 merus with 2 spines on dorsal margin (excluding 1
distal spine), ventral margin unarmed, outer surface with
1 strong proximal spine (Figs. 9A, 11A, E–G). P5 merus

Gordonopsis robusta Ng, Padate & Saravanane, 2019: 511, figs. 1–4.

Material examined. Holotype: male (33.5 × 44.9 mm)(CMLRE IO/SS/BRC/00082), Andaman Sea, FORVSS
station 36708, 13.27°N, 93.26°E, 635 m, HSDT (CV), coll.
S. S. Cubelio, 26 November 2017. Paratype: 1 young female(15.6 × 20.8 mm) (CMLRE IO/SS/BRC/00083), same data
as holotype.
Diagnosis. Male: carapace longitudinally ovate, width tolength ratio 0.75, distinctly wider posteriorly than anteriorly;
dorsal carapace surface with well-defined regions, separated
by broad, deep grooves; lateral margin distinctly convex;
dorsal parts with dense soft setae partially obscuring surface;lateral parts densely setose, completely obscuring surface(Figs. 12A–D, 13A, B). Rostrum relatively long, sharp,with 2 relatively long, obliquely directed pseudorostralspines, just shorter than rostrum (Fig. 12C). Supraorbital
margin relatively narrow, C-shaped; pseudorostral spines
directed obliquely laterally at angle of about 45° (Fig.
12C). Supraorbital margin relatively narrow, C-shaped;
pseudorostral spines directed obliquely laterally at angleof about 45° (Fig. 12C). Eyes with short ocular peduncle,
cornea prominent; no discernible orbit (Fig. 12C). Hepatic
region gently inflated, with short obliquely directed spine(Fig. 12C). Gastric region without spines (Fig. 12C). Gastricgroove well marked, with distinct ovate gastric fossae justabove (Fig. 12C). Cardiac region swollen; branchial region
inflated, with distinct branchio-cardiac grooves (Fig. 12C).
Latero-posterior tubercle strong, sharp (Fig. 12C). Base ofantenna with short spine. Antennal flagellum short, second
and third articles thick, setose. Epistome triangular. Third
maxilliped pediform, merus elongate with dentiform externalangle (Fig. 13C). Chelipeds long; fingers short, less than half
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Fig. 9. Gordonopsis alaini, new species, holotype male (15.4 × 10.0 mm) (MNHN-IU-2017-9049), Madagascar. A, overall habitus; B,
dorsal view of carapace; C, dorso-frontal view of carapace.

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Fig. 10. Gordonopsis alaini, new species, holotype male (15.4 × 10.0 mm) (MNHN-IU-2017-9049), Madagascar. A, lateral view of
cephalothorax; B, frontal view of cephalothorax; C, left third maxilliped; D, ventral view showing buccal cavity, epistome, antennae, andantennules; E, outer view of right carpus and chela; F, dorsal view of left cheliped; G, dorsal view of right cheliped; H, ventral view ofright G1; I, ventral view of right G2.

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Fig. 11. Gordonopsis alaini, new species, holotype male (15.4 × 10.0 mm) (MNHN-IU-2017-9049), Madagascar. A, dorsal view ofcarapace showing relative P5 length; B, ventral view of cephalothorax showing pleon and unarmed P2–P4 coxae; C, ventral view of
cephalothorax showing sternopleonal cavity and unarmed P2–P4 coxae; D, pleon; E–H, right P2–P5, respectively (all to same scale); I,
right P5 pseudochela (same scale as E–H); J, left P5; K, left P5 pseudochela.

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Fig. 12. Gordonopsis robusta Ng, Padate & Saravanane, 2019. A, C, E, holotype male (33.5 × 44.9 mm) (CMLRE), Andaman Sea; B,D, paratype female (15.6 × 20.8 mm) (CMLRE), Andaman Sea. A, B, overall habitus; C, dorsal view of carapace; D, dorsal view ofcarapace showing relative P5 length; E, outer view of right chela.

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Fig. 13. Gordonopsis robusta Ng, Padate & Saravanane, 2019, holotype male (33.5 × 44.9 mm) (CMLRE), Andaman Sea. A, dorso-lateralview of cephalothorax; B, frontal view of cephalothorax; C, right third maxilliped; D, E, ventral view of cephalothorax showing pleon andcoxae; F, dorsal view of carpus of right cheliped; G–I, left P3–P5 meri and leg, respectively (all to same scale); J, left P5 pseudochela;K, ventral view of right G1; L, ventral view of right G2.

length of palm; surface gently rugose with 4 or 5 longitudinalrows of small granules, margins with sharp granules and shortspines; carpus longitudinally ovate, outer margin with 8–10
short spines, distal edge with short spine, inner margin with
5 or 6 spines, dorsal surface with ridge lined with 3–5 short
sharp tubercles or granules; merus triangular in cross-section,
relatively long, curved, dorsal margin with 5 short spinesand distal 2 spines bracketing chela, outer ventral margin
with 16–18 spines and spinules, inner ventral margin with
6–8 spines or spinules (Figs. 12A, E, 13F). Ambulatory
legs relatively long; basis-ischium with small granules, notspines; P2 merus with 6 spines or sharp tubercles on dorsal
margin (excluding 1 distal spine), ventral margin with 3–5

spinules or tubercles; P3 merus with 5 spines on dorsal
margin (excluding 1 distal spine), ventral margin with 1 or
2 sharp tubercles; P4 merus not known (Figs. 12A, B, 13G,
H). P5 merus slender, unarmed on all margins, just reaching
gastric groove when folded anteriorly; carpus long, propodus
short, enlarged, forming prominent pseudochela with stout,
gently curved dactylus; occlusal margin of fixed finger with
8 spines, that of dactylus with 8 spines (Figs. 12D, 13I, J).
Outer margins of P2–P4 coxae smooth, unarmed (Fig. 13D,
E). Telson triangular, with gently convex lateral margins andsharp tip (Fig. 13D, E). G1 short, stout, distal part gently
upcurved, tip concave (Fig. 13K). G2 stout, tubular, length
subequal to G1, distal portion cup-shaped (Fig. 13L). Female:283

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Fig. 14. Gordonopsis pacifica Takeda & Suyama, 2019, holotype male (31.0 × 43.0 mm) (NSMT-Cr 26053), Okino-Torishima Island,
Japan. A, overall habitus; B, dorsal view of carapace; C, dorso-frontal view of carapace.

non-sexual characters similar to male except cheliped merus
with 6 spines on upper margin, 8 short spines and tubercles onouter ventral margin, 5 or 6 sharp tubercles on inner ventral
margin; P2 merus with 5 spines on dorsal margin, ventral
margin with 1 sharp tubercle; P3 merus with 5 spines on
dorsal margin, ventral margin with 1 sharp tubercle; P4 with

3 spines on dorsal margin, ventral margin unarmed; telson
broadly triangular with convex lateral margins.
Colour. Not known.
Remarks. See general discussion for comparisons withcongeners.
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Gordonopsis pacifica Takeda & Suyama, 2019
(Figs. 14–16)

Colour. The freshly collected specimen has a yellowishbrown carapace with the chelipeds and ambulatory leg brightred (Takeda & Suyama, 2019: fig. 1B).

Gordonopis pacifica Takeda & Suyama, 2019: 46, figs. 1B, 2–4.

Remarks. The holotype specimen is in poor condition withseveral parts of the carapace damaged, pereiopod missing
and most of the pleon absent. It appears to have recently
moulted given that the cuticle is not completely hardened
and still quite brittle. Some of the spines on the pereiopods
are broken off but their bases can still be discerned.

Material examined. Holotype: male (31.0 × 43.0 mm)(NSMT-Cr 26053), south of Okinotorishima (= Okinotori
Island), 20°25′31″N, 136°04′52″E, southern Japan, 300–600
m deep, coll. 13 January 2006.
Diagnosis. Male: carapace longitudinally ovate, width tolength ratio 0.72, distinctly wider posteriorly than anteriorly;
dorsal carapace surface with well-defined regions, separated
by broad, deep grooves; lateral margin gently convex; dorsal
parts with numerous setae that partially obscure surface;lateral parts with soft setae that almost obscure surface,denser on hepatic, pterygostomial and suborbital regions(Figs. 14A–C, 15A, B). Rostrum long, sharp, with 2 relatively
short, obliquely directed pseudorostral spines, just shorter
than rostrum (Fig. 14B). Supraorbital margin relatively wide;
pseudorostral spines directed obliquely laterally at angleof about 20° (Fig. 14B). Eyes with short ocular peduncle,
cornea prominent; no discernible orbit (Fig. 14B). Hepatic
region gently inflated, with short obliquely directed spine(Fig. 14B). Gastric region without spines (Fig. 14B). Gastricgroove well marked, with distinct ovate gastric fossae justabove (Fig. 14B). Cardiac region swollen; branchial region
inflated, with distinct branchio-cardiac grooves (Fig. 14B).
Latero-posterior tubercle on carapace not distinct, justdiscernible as low tubercle (Fig. 14B). Base of antenna
with short spine. Antennal flagellum short, second and third
articles thick, setose. Epistome triangular. Third maxilliped
pediform, merus elongate with dentiform external angle (Fig.
15C). Chelipeds long; fingers long, greater than half lengthof palm; surface almost smooth with low slightly oblique
longitudinal ridge; carpus longitudinally ovate, outer margin
with 3 long spines, distal edge with 1 long spine, inner margin
with 1 long spine, dorsal surface with longitudinal row of
3 short spines; merus triangular in cross-section, relatively
long, curved, dorsal margin with 7 or 8 spines and distal 2
short spines bracketing chela, outer ventral margin with 7
or 8 spines, inner ventral margin with 6 short spines (Figs.
14A, 15E–G). Ambulatory legs long; basis-ischium with 4
spines on each margin; P2 merus with 3 or 4 spines on dorsal
margin (excluding 1 distal spine), ventral margin with 1 or 2
spines; P3 merus with 2 spines on dorsal margin (excluding
1 distal spine), ventral margin with 1 spine; P4 merus with
2 spines on dorsal margin (excluding 1 distal spine), ventral
margin with 1 spine, outer surface with 1 proximal tubercle(Figs. 14A, 16E–G, I, K, L). P5 merus slender, unarmed on
all margins, reaching just beyond gastric groove when folded
anteriorly; carpus long, propodus short, enlarged, forming
prominent pseudochela with stout, gently curved dactylus;
occlusal margin of fixed finger with 7 spines, that of dactylus
with 8 spines (Fig. 16A, H, J). Outer margin of P2 coxa withl short, stout spine on distal edge; outer margin of P3 coxa
with 1 short, stout spine on proximal edge, outer margin of
P4 coxa with 1 or 2 short, stout spines on proximal edge
(Fig. 16C, D). Pleon missing from holotype.

See general discussion for comparisons with congeners.
Gordonopsis hera, new species(Figs. 17–20)
Material examined. Holotype: ovigerous female (21.8 × 31.2mm) (MNHN-IU-2013-2245), station CP 4246, northwest
of Vitu Island, Bismarck Sea, 04°07′S, 148°09′E, Papua
New Guinea, 695–899 m, coll. MADEEP Expedition, 22
April 2014.
Diagnosis. Female: carapace longitudinally pyriform,
width to length ratio 0.70, distinctly wider posteriorly thananteriorly; dorsal carapace surface with well-defined regions,separated by broad, deep grooves; lateral margin gently
convex to almost straight; dorsal parts with numerous stiff
setae that do not obscure surface; lateral parts with denser
soft and stiff setae that partially obscure surface, denser
on hepatic, pterygostomial and suborbital regions (Figs.
17A–C, 18A, B). Rostrum long, sharp, with 2 relatively
short, obliquely directed pseudorostral spines, just shorter
than rostrum (Fig. 17B). Supraorbital margin relatively wide;
pseudorostral spines directed obliquely laterally at angleof about 30° (Fig. 17B). Eyes with short ocular peduncle,
cornea prominent; no discernible orbit (Fig. 17B). Hepatic
region gently inflated, with short obliquely directed spine(Fig. 17B). Gastric region without spines (Fig. 17B). Gastricgroove well marked, with distinct ovate gastric fossae justabove (Fig. 17B). Cardiac region swollen; branchial region
inflated, with distinct branchio-cardiac grooves (Fig. 17B).
Latero-posterior tubercle on carapace low, just discernible
as granule (Fig. 17B). Base of antenna with short spine(Fig. 18D). Antennal flagellum short, second and third
articles thick, setose. Epistome triangular (Fig. 18D). Third
maxilliped pediform, merus elongate with dentiform externalangle (Fig. 18C). Chelipeds long; fingers long, greater thanhalf length of palm; surface gently rugose with scatteredsmall granules; carpus longitudinally ovate, outer margin
with 3 or 4 long spines, distal edge with 1 long spine, inner
margin with 1 long spine, dorsal surface with longitudinalrow of 3 spines; merus triangular in cross-section, relatively
long, curved, dorsal margin with 8 spines and distal 2 spines
bracketing chela, outer ventral margin with 6 spines, inner
ventral margin with 4 or 5 spinules (Fig. 18E–I). Ambulatory
legs very long; basis-ischium with 4 spines on each margin;
P2 merus with 3 spines on dorsal margin (excluding 1 distal
spine), ventral margin with 1 spine; P3 merus with 2 spines
on dorsal margin (excluding 1 distal spine), ventral marginunarmed; P4 merus with 1 spine on dorsal margin (excluding285

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Fig. 15. Gordonopsis pacifica Takeda & Suyama, 2019, holotype male (31.0 × 43.0 mm) (NSMT-Cr 26053), Okino-Torishima Island,
Japan. A, lateral view of cephalothorax; B, frontal view of cephalothorax; C, left third maxilliped; D, dorsal view of front; E, outer viewof merus and carpus of right cheloped; F, outer view of right chela; G, dorsal view of carpus of right cheliped.

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Fig. 16. Gordonopsis pacifica Takeda & Suyama, 2019, holotype male (31.0 × 43.0 mm) (NSMT-Cr 26053), Okino-Torishima Island,
Japan. A, dorsal view of carapace showing relative P5 length; B, sternopleonal cavity; C, right P2–P4 coxae and basis-ischia; D, left P2–P4
coxae; E–H, left P2–P5, respectively; I, dorsomesial view of proximal part of merus of P4 showing tubercle on outer surface (arrow); J,
left P5 pseudochela; K, L, right P2 and P3, respectively; M, N, left G1; O, left G2. All ambulatory legs shown to same scale. M–O after
Takeda & Suyama (2019: fig. 4B–D).

Variation. The photographs from the Tokelau Seamount(Fig. 20) appear to show large specimens of G. hera, which
agree very well with the holotype female, including in thepereiopod proportions and armature.

1 distal spine), ventral margin unarmed, outer surface smooth,
without trace of spinule or granule (Figs. 17A, 19D–F). P5
merus slender, unarmed on all margins, reaching beyond
gastric groove when folded anteriorly; carpus long, propodus
short, enlarged, forming prominent pseudochela with stout,
gently curved dactylus; occlusal margin of fixed finger with
7 spines, that of dactylus with 7 spines (Fig. 19A, G, H).
Outer margin of P2 coxa with l short, stout spine on distal
edge; outer margin of P3 coxa with 1 short, stout spine on
proximal edge, outer margin of P4 coxa with 0 or 1 short,stout spine on proximal edge (Fig. 18J, K). Proximal partof telson subtruncate, with distal half triangular (Fig. 19B).

Colour. In life, the carapace is whitish to brown; with theambulatory legs clear or pale orange with white spines(Figs. 20, 30A).
Etymology. Hera is a Greek goddess, sister and wife of Zeus
who was educated by Okeanos and Tethys; she was the one
who placed Karkinos in the stars forming the constellation287

Ng & Richer de Forges: Revision of Gordonopsis

Fig. 17. Gordonopsis hera, new species, holotype ovigerous female (21.8 × 31.2 mm) (MNHN-IU-2013-2245), Papua New Guinea. A,
overall habitus; B, dorsal view of carapace; C, dorso-frontal view of carapace.

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Fig. 18. Gordonopsis hera, new species, holotype ovigerous female (21.8 × 31.2 mm) (MNHN-IU-2013-2245), Papua New Guinea. A,
lateral view of cephalothorax; B, frontal view of cephalothorax; C, left third maxilliped; D, ventral view showing buccal cavity, epistome,
antennae, and antennules; E, dorsal view of carpus of left cheliped (denuded); F, dorsal view of carpus of right cheliped (denuded); G,
outer view of right chela; H, inner view of right chela; I, dorsal view of right cheliped; J, right P2–P4 coxae and basis-ischia (denuded);K, left P2–P4 coxae (denuded).

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Fig. 19. Gordonopsis hera, new species, holotype ovigerous female (21.8 × 31.2 mm) (MNHN-IU-2013-2245), Papua New Guinea. A,
dorsal view of carapace showing relative P5 length; B, ventral view of cephalothorax showing pleon; C, telson and pleon somites 5 and
6; D–G, right P2–P5, respectively (all to same scale); H, right P5 pseudochela.

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Fig. 20. Gordonopsis hera, new species, photographed in situ, specimens not collected. Ufiata Seamount, Tokelau Seamounts, 8°09.50′S,
172°54.08′W, 755–995 m, March 2017. Photographs courtesy of the U.S. National Oceanographic and Atmospheric Administration Officeof Ocean Exploration and Research.

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Cancer. It alludes to, and honours, our friend and respectedcolleague, Danièle Guinot, for her stellar work on marine
Brachyura over the years. The name is used as a noun.

8 spines and distal 2 spines bracketing chela, outer ventral
margin with 7 or 8 spines, inner ventral margin with 5 or 6
spinules (Fig. 22E–H). Ambulatory legs very long; basisischium with 4 distinct curved spines on each margin, thaton P4 sometimes with additional ventral spine; P2 merus
with 4 spines on dorsal margin (excluding 1 distal spine),
ventral margin with 1 or 2 spinules or sharp granules; P3
merus with 3 spines on dorsal margin (excluding 1 distal
spine), ventral margin with 1 spinule; P4 merus with 2 spines
on dorsal margin (excluding 1 distal spine), ventral marginunarmed, outer surface with 1 strong proximal spine (Figs.
21A, 23C–E). P5 merus slender, unarmed on all margins,reaching beyond gastric groove when folded anteriorly;
carpus long, propodus short, enlarged, forming prominent
pseudochela with stout, gently curved dactylus; occlusal
margin of fixed finger with 8 spines, that of dactylus with
8 spines (Fig. 23A, F, G). Outer margin of P2 coxa with lshort, stout spine on distal edge; outer margin of P3 coxa
with 1 or 2 strong curved spines on each edge, outer marginof P4 coxa with 2 strong curved spines on each edge (Figs.
22I, J, 23B, H). Proximal part of telson subtruncate, with
distal half triangular (Fig. 23B).

Remarks. Specimens were observed by a submersible, inMarch 2017, at Ufiata Seamount in the Tokelau Seamounts
in the central Pacific (8°09.50′S, 172°54.08′W), at depths of
755–995 m (Fig. 20). Although no specimens were collected,
the photographs agree very well with what is here described
for G. hera and we believe they are conspecific. Theseseamounts are some 4,000 km east of the type locality of
G. hera in the Bismarck Sea.
See general discussion for comparisons with congeners.
Carrying behaviour. The specimens from the Tokelau
Seamounts in the central Pacific were all observed carrying
an unidentified hydroid colony (Fig. 20). This is the firstrecord of carrying behaviour in this genus (see Guinot etal., 1995; Guinot & Wicksten, 2015).
Gordonopsis phorcys, new species(Figs. 21–23)

Colour. Not known.

Material examined. Holotype: female (10.9 × 16.8 mm)(MNHN-IU-2008-12211 = MNHN B30261), station CP2197,
southwest of Santa Isabel, 8°24.4′N, 159°22.5′E, Solomon
Islands, 897–1,057 m, coll. Expedition SALOMON 2, N.O.
Alis, November 2004.

Etymology. The species is named after Phorcys, a primordial
Greek sea god, son of Gaia, brother and husband of Ceto.
The name is used as a noun.
Remarks. See general discussion for comparisons withcongeners.

Diagnosis. Female: carapace longitudinally ovate, width tolength ratio 0.65, distinctly wider posteriorly than anteriorly;
dorsal carapace surface with well-defined regions, separated
by broad, deep grooves; lateral margin gently convex; dorsal
parts with scattered soft setae that do not obscure surface;lateral parts with setae that do not obscure surface (Figs.
21A–C, 22A, B). Rostrum long, sharp, with 2 long, obliquely
directed pseudorostral spines, just shorter than rostrum (Fig.
21B). Supraorbital margin relatively narrow, C-shaped;
pseudorostral spines directed obliquely laterally at angleof about 45° (Fig. 21B). Eyes with short ocular peduncle,
cornea prominent; no discernible orbit (Fig. 21B). Hepatic
region gently inflated, with short obliquely directed spine(Fig. 21B). Gastric region without spines (Fig. 21B). Gastricgroove well marked, with distinct ovate gastric fossae justabove (Fig. 21B). Cardiac region swollen; branchial region
inflated, with distinct branchio-cardiac grooves (Fig. 21B).
Latero-posterior tubercle on carapace low, just discernible
as granule (Fig. 21B). Base of antenna with distinct spine(Fig. 22D). Antennal flagellum short, second and third
articles thick, setose. Epistome triangular (Fig. 22D). Third
maxilliped pediform, merus elongate with angular externalangle (Fig. 22C). Chelipeds long; fingers long, greater thanhalf length of palm; surface gently rugose with scatteredsmall granules; carpus longitudinally ovate, outer margin
with 1 or 2 long spines and sometimes a third spinule,distal edge with 1 long spine, inner margin with 1 longspine, sometimes with 1 more spinule, dorsal surface withlongitudinal row of 3 short spines; merus triangular incross-section, relatively long, curved, dorsal margin with

Gordonopsis ceto, new species(Figs. 24–26)
Material examined. Holotype: female (9.3 × 13.6 mm)(NTOU), station CST 12, Horse Shoe Ridge, hard bottom
without mud, with many white dead bivalves and one
Bathymodiolus shell, many soft corals and squat lobsters,
22°0.953′N, 118°53.955′E – 22°4.864′N, 118°52.785′E,
758–1,346 m, South China Sea, Taiwan, coll. T.-Y. Chan,
29 April 2016.
Diagnosis. Female: carapace longitudinally ovate, width tolength ratio 0.68, distinctly wider posteriorly than anteriorly;
dorsal carapace surface with well-defined regions, separated
by broad, deep grooves; lateral margin convex; dorsal
parts with scattered soft setae that do not obscure surface;lateral parts with setae that do not obscure surface (Figs.
24A–C, 25A, B). Rostrum long, sharp, with 2 long, obliquely
directed pseudorostral spines, just shorter than rostrum (Fig.
24A). Supraorbital margin relatively narrow, C-shaped;
pseudorostral spines directed obliquely laterally at angleof about 45° (Fig. 24A). Eyes with short ocular peduncle,
cornea prominent; no discernible orbit (Fig. 24A). Hepatic
region gently inflated, with short obliquely directed spine(Fig. 24A). Gastric region without spines (Fig. 24A). Gastricgroove well marked, with distinct ovate gastric fossae justabove (Fig. 24A). Cardiac region swollen; branchial region
inflated, with distinct branchio-cardiac grooves (Fig. 24A).
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Fig. 21. Gordonopsis phorcys, new species, holotype female (10.9 × 16.8 mm) (MNHN-IU-2008-12211), Solomon Islands. A, overall
habitus; B, dorsal view of carapace; C, dorso-frontal view of carapace.

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Fig. 22. Gordonopsis phorcys, new species, holotype female (10.9 × 16.8 mm) (MNHN-IU-2008-12211), Solomon Islands. A, lateral viewof cephalothorax; B, frontal view of cephalothorax; C, left third maxilliped; D, ventral view showing buccal cavity, epistome, antennae,and antennules; E, outer view of merus and carpus of right cheliped; F, outer view of right carpus and chela; G, dorsal view of leftcheliped; H, dorsal view of right cheliped; I, right P2–P4 coxae and basis-ischia (denuded); J, left P2–P4 coxae and basis-ischia (denuded).

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Fig. 23. Gordonopsis phorcys, new species, holotype female (10.9 × 16.8 mm) (MNHN-IU-2008-12211), Solomon Islands. A, dorsal
view of carapace showing relative P5 length; B, ventral view of cephalothorax showing coxae, basis-ischia, and pleon; C–F, right P2–P5,
respectively (all to same scale); G, right P5 pseudochela; H, ventral view of cephalothorax showing sternopleonal cavity, coxae, andbasis-ischia.

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Fig. 24. Gordonopsis ceto, new species, holotype female (9.3 × 13.6 mm) (NTOU), South China Sea. A, overall habitus; B, dorsal viewof carapace; C, dorso-frontal view of carapace.

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Fig. 25. Gordonopsis ceto, new species, holotype female (9.3 × 13.6 mm) (NTOU), South China Sea. A, lateral view of cephalothorax;
B, frontal view of cephalothorax; C, left third maxilliped; D, ventral view showing buccal cavity, epistome, antennae, and antennules;
E, outer view of merus and carpus of right cheliped; F, outer view of right carpus and chela; G, dorsal view of left cheliped; H, dorsal
view of right cheliped.

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Fig. 26. Gordonopsis ceto, new species, holotype female (9.3 × 13.6 mm) (NTOU), South China Sea. A, dorsal view of carapace showing
relative P5 length; B, ventral view of cephalothorax showing coxae, basis-ischia, and pleon; C, right P2–P4 coxae and basis-ischia(denuded); D, left P2–P4 coxae and basis-ischia (denuded); E–H, right P2–P5, respectively (all to same scale); I, right P5 pseudochela.

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Latero-posterior tubercle on carapace low, just discernible
as granule (Fig. 24A). Base of antenna with distinct spine(Fig. 25D). Antennal flagellum short, second and third
articles thick, setose. Epistome triangular (Fig. 25D). Third
maxilliped pediform, merus elongate with angular externalangle (Fig. 25C). Chelipeds long; fingers long, greater thanhalf length of palm; surface gently rugose with scatteredsmall granules; carpus longitudinally ovate, outer margin
with 2 or 3 long spines, distal edge with 1 long spine, inner
margin with 1 long spine, sometimes with additional spinule,dorsal surface with longitudinal row of 2 or 3 spinules;
merus triangular in cross-section, relatively long, curved,
dorsal margin with 7 spines and distal 2 spines bracketingchela, outer ventral margin with 7 spines, inner ventral
margin with 3–5 spinules (Fig. 25E–H). Ambulatory legsvery long; basis-ischium with 4 spines on each margin; P2
merus with 3 spines on dorsal margin (excluding 1 distal
spine), ventral margin with 1 or 2 spinules or sharp granules;
P3 merus with 2 spines on dorsal margin (excluding 1 distal
spine), ventral margin with 1 spinule; P4 merus with 1 spine
on dorsal margin (excluding 1 distal spine), ventral marginunarmed, outer surface smooth, without trace of spinule or
granule (Figs. 24A, 26A, E–G). P5 merus slender, unarmedon all margins, reaching beyond gastric groove when folded
anteriorly; carpus long, propodus short, enlarged, forming
prominent pseudochela with stout, gently curved dactylus;
occlusal margin of fixed finger with 8 spines, that of dactylus
with 7 or 8 spines (Fig. 26H, I). Outer margin of P2 coxa
with 1 short, stout spine on proximal edge, outer margin of
P4 coxa with 1 or 2 short, stout spines on each edge (Fig.
26B–D). Proximal part of telson subtrapezoidal, with distal
half triangular (Fig. 26B).

30C). Rostrum relatively long, sharp, with 2 long, obliquely
directed pseudorostral spines, just shorter than rostrum (Fig.
27B). Supraorbital margin relatively narrow, C-shaped;
pseudorostral spines directed obliquely laterally at angleof about 45° (Fig. 27B). Eyes with short ocular peduncle,
cornea prominent; no discernible orbit (Fig. 27B). Hepatic
region gently inflated, with short obliquely directed spine(Fig. 27B). Gastric region without spines (Fig. 27B). Gastricgroove well marked, with distinct ovate gastric fossae justabove (Fig. 27B). Cardiac region swollen; branchial region
inflated, with distinct branchio-cardiac grooves (Fig. 27B).
Latero-posterior tubercle on carapace barely visible only
as slight swelling (Fig. 27B). Base of antenna with distinct
spine (Fig. 28D). Antennal flagellum short, second and third
articles thick, setose. Epistome triangular (Fig. 28D). Third
maxilliped pediform, merus elongate with slightly rounded
external angle (Fig. 28C). Chelipeds long; fingers long,slightly greater than half length of palm; surface gently
rugose with scattered small granules; carpus longitudinallyovate, outer, distal and inner margins with 1 long spine each,dorsal surface with low ridge, unarmed; merus triangular incross-section, relatively long, curved, dorsal margin with 6
or 7 spines and 1 distal spine adjacent to chela, outer ventral
margin with 6 or 7 spines, inner ventral margin with 5 or 6
spinules (Figs. 27A, 28E–H). Ambulatory legs long; basisischium with small granules, not spines; P2 merus with 3
spines on dorsal margin (excluding 1 distal spine), ventral
margin unarmed; P3 merus with 2 or 4 spinules on dorsal
and subdorsal margins (excluding 1 distal spine), ventral
margin unarmed; P4 merus with 0 or 4 spinules on dorsal
and subdorsal margins (excluding 1 distal spine), ventral
margin unarmed, outer surface with 1 distinct granule (Figs.
27A, 29A, F–H). P5 merus slender, unarmed on all margins,reaching beyond gastric groove when folded anteriorly;
carpus long, propodus short, enlarged, forming prominent
pseudochela with stout, gently curved dactylus; occlusal
margin of fixed finger with 7 spines, that of dactylus with
7 spines (Fig. 29A, I, J). Outer margins of P2–P4 coxaesmooth, unarmed (Fig. 29C–E). Proximal part of telson
subcircular with strongly convex lateral margins, distal part
triangular (Fig. 29B).

Colour. In life, the carapace is greyish-brown, and thechelipeds and ambulatory legs are orange (Fig. 30B).
Etymology. The species is named after Ceto, a Greek sea
goddess, sister and wife of Phorcys. The name is used asa noun.
Remarks. See general discussion for comparisons withcongeners.

Colour. The carapace and appendages are dirty white, withthe setae yellowish-brown (Fig. 30C).

Gordonopsis velutina, new species(Figs. 27–29)

Etymology. The name is derived from the Latin word forvelvety, alluding to the dense setae all over the body ofthe species.

Material examined. Holotype: female (20.8 × 27.8 mm)(MNHN-IU-2013-2269), station CP4249, southeast of
Sherburne reefs, southeast Admiralty Islands, Bismark Sea,
3°31′S, 148°05′E, 598–650 m, coll. Expedition MADEEP,
N.O. Alis, 23 April 2014.

Remarks. See general discussion for comparisons withcongeners.

Diagnosis. Female: carapace longitudinally ovate, width tolength ratio 0.75, distinctly wider posteriorly than anteriorly;
dorsal carapace surface with well-defined regions, separated
by broad, deep grooves; lateral margin distinctly convex;
dorsal parts with numerous soft and stiff setae that almost
completely obscure surface; lateral parts with denser
setae that obscure surface, relatively denser on hepatic,
pterygostomial and suborbital regions (Figs. 27A–C, 28A, B,

GENERAL DISCUSSION
Gordonopsis, as diagnosed in this revision, can be divided
into two groups of species based on whether the outer margins
of P2–P4 coxae possesses a spine. In one group of species,
comprising G. profundarum s. str., G. alaini, G. robusta,
and G. velutina, the outer margin of the P2–P4 coxae is299

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Fig. 27. Gordonopsis velutina, new species, holotype female (20.8 × 27.8 mm) (MNHN-IU-2013-2269), Admiralty Islands. A, overall
habitus; B, dorsal view of carapace; C, dorso-frontal view of carapace.

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Fig. 28. Gordonopsis velutina, new species, holotype female (20.8 × 27.8 mm) (MNHN-IU-2013-2269), Admiralty Islands. A, lateral viewof cephalothorax; B, frontal view of cephalothorax; C, left third maxilliped; D, ventral view showing buccal cavity, epistome, antennae,and antennules; E, outer view of merus and carpus of right cheliped; F, outer view of right carpus and chela; G, dorsal view of leftcheliped; H, dorsal view of right cheliped.

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Fig. 29. Gordonopsis velutina, new species, holotype female (20.8 × 27.8 mm) (MNHN-IU-2013-2269), Admiralty Islands. A, dorsal
view of carapace showing relative P5 length; B, ventral view of cephalothorax showing coxae, basis-ischia, and pleon; C, ventral viewof cephalothorax showing sternopleonal cavity and coxae; D, right P2–P4 coxae and basis-ischia; E, left P2–P4 coxae and basis-ischia;
F–I, right P2–P5, respectively (all to same scale); J, right P5 pseudochela.

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Fig. 30. Colour in life. A, Gordonopsis hera, new species, holotype ovigerous female (21.8 × 31.2 mm) (MNHN-IU-2013-2245), Papua New
Guinea; B, G. ceto, new species, holotype female (9.3 × 13.6 mm) (NTOU), South China Sea; C, G. velutina, new species, holotype female(20.8 × 27.8 mm) (MNHN-IU-2013-2269), Admiralty Islands. Photographs: A, C, Laure Corbari (MNHN); B, Chan Tin-Yam (NTOU).

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smooth and entire. With the exception of G. velutina fromthe western Pacific, these species are from the Indian Ocean.
In the second group of species, comprising G. pacifica, G.
hera, G. phorcys, and G. ceto, the outer margin of P2–P4
coxae has one or two spines that may be low but are always
visible, at least as a tubercle (although some of the coxae on
individual specimens may appear smooth); all are western
Pacific in distribution. In these species, the spines on thedorsal margin of the P2–P4 basis-ischium and merus arealso proportionately longer and more prominent (e.g., Figs.
18J, K, 19B, 22I, J, 23B, H, 26B–D).

tubercle (Fig. 16G, I) (versus outer surface of the proximal
part of the merus of P4 is smooth in G. hera; Fig. 19F).
Gordonopsis phorcys and G. ceto appear to be closely related,with a similar carapace and elongate ambulatory legs. The
main difference is that in G. phorcys, the outer margin ofeach P3 and P4 coxa has two long spines (Figs. 22I, J, 23B,
H) (versus with only one spine on each P3 and P4 coxa in
G. ceto; Fig. 26B–D); and the outer surface of the P4 merus
has one perpendicular spine on the proximal part (versus
outer surface of the P4 merus is completely smooth in G.
ceto). Gordonopsis hera is the only other species with theouter surface of the P4 merus smooth and unarmed.

Gordonopsis velutina is the most distinctive species of thegenus; it uniquely has the distal edge of the dorsal marginof the cheliped merus armed with only one spine (Fig. 28G)(versus with two distinct spines at this position in all othercongeners, e.g., Figs. 3F, 7G, 13F, 15G, 22E, 25G, H); andthe carapace and pereiopods are covered with long dense
setae, which hide the surfaces and margins and are difficult
to brush off (Fig. 27A–C) (versus less dense setae coveringor with soft setae that can be brushed off easily; Figs. 2A–C,
6A–C, 9A–C, 21A–C, 24A–C). Species like G. robusta, G.
pacifica, and G. hera are setose (Fig. 12A–D, 14A–C, 17A–C)
but none to the extent observed in G. velutina.

The carapace shape is useful for separating several species.
The carapace is distinctly ovate, with the posterior partmore globose and lateral margins distinctly convex in G.
profundarum, G. robusta, G. pacifica, G. phorcys, G. ceto,and G. velutina (Figs. 2B, 6B, 12C, D, 14B, 21B, 24B, 27B).
The carapace is narrower, with the lateral margins straighterand less convex in G. alaini and G. hera (Figs. 9B, 17B).
The carapace of the four western Pacific species, as well as
the Indian Ocean G. alaini, has only a small latero-posterior
carapace tubercle or granule (e.g., Figs. 9B, 17B). This is in
sharp contrast to the condition in G. profundarum s. str. andG. robusta, in which the latero-posterior tubercle is large
and prominent (e.g., Figs. 2B, 6B, 12B).

The armature on the cheliped carpus appears to be independentof sex and separates the species into three forms. One form
(G. alaini and G. velutina) has only one spine on each of theouter and inner margins and the dorsal ridge is smooth andunarmed (e.g., Figs. 10E–G, 28G, H). The second form (G.
pacifica, G. hera, G. phorcys, and G. ceto) has two or morespines and spinules on the outer margin and one spine on
the inner margin, with three spines or spinules on the dorsal
ridge (e.g., Figs. 18E, F, I, 22G, H, 25G, H). The third form
(G. profundarum and G. robusta) has three or more spines
and spinules on each of the outer and inner margins and thedorsal ridge is not armed with spines or spinules (e.g., Figs.
3F, G, 7G, 13F). In G. profundarum, however, the dorsal
ridge has a row of low granules, while in G. robusta, theridge has a row of low sharp tubercles.

The G1 of the three species for which this structure is
known differs significantly, but it is difficult to evaluate thesignificance of differences as all are singletons. That of G.
profundarum has the distal part subconical in shape withthe tip rounded (Figs. 4H, 8H). In G. alaini, the G1 distal
part is proportionately broader, more truncate with the tip
gently concave with a sharper tip (Fig. 10H). The distal partof the G1 tip in G. robusta is gently curved upwards withthe tip concave, appearing almost bifurcate (Fig. 13K). In G.
pacifica, the tip of the G1 is acute and sharp (Fig. 16M, N).
The material on hand is too limited to determine the possible
degree of variation in the various characters observed,
notably in the shape of the carapace, strength of the lateroposterior carapace tubercle, and ambulatory leg proportions.
In G. profundarum and G. robusta at least, which are each
represented by a large adult male and a young female,these characters certainly do not vary between sex and size,
suggesting they may be taxonomically reliable. This also
appears to be the case for the cheliped carpus and merus,
as well as armature on P4 (notably the presence or absenceof a median granule or spine on the outer proximal surface).

Gordonopis pacifica and G. hera share several characters:
the supraorbital margin is proportionately wider and thepseudorostral spines are relatively shorter and directed
only slightly obliquely laterally at an angle of 20–30°(Figs. 14B, 15D, 17B). In all other species of Gordonopsis,the supraorbital margin is C-shaped, narrower, and thepseudorostral spines are longer and directed almost 45°
obliquely laterally (e.g., Fig. 6B). Gordonopis pacifica caneasily be separated from G. hera by the distinctly higher
and more inflated carapace when viewed laterally andfrontally (Fig. 15A, B) (versus carapace distinctly lower
in G. hera; Fig. 18A, B); P2–P4, particularly the meri, areproportionately shorter (Fig. 16E–G, K, L) (versus meri ofP2–P5 proportionally longer in G. hera; Fig. 19D–F); theP5 is proportionally shorter, reaching just beyond the gastricgroove (Fig. 16A) (versus longer P5 extending well beyond
gastric groove in G. hera; Fig. 19A); and the outer surface ofthe proximal part of the merus of P4 is armed with a distinct

The recognition of a second species, G. alaini, in the western
Indian Ocean is notable. Despite the proximity of theMaldives to India and Madagascar, the deep waters in thatpart of the Indian Ocean have a complex geological history
which appears to have affected the species composition andbiogeography of the region. The recognition of G. alaini
from Madagascar, distinct from the Maldives and Somalia(G. profundarum s. str.) is not surprising. Guinot & Richer de

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Forges (1995) recognised three species of Moloha Barnard,
1946, from that part of the Indian Ocean, M. alisae Guinot& Richer de Forges, 1995 (Seychelles), M. grandperrini
Guinot & Richer de Forges, 1995 (Maldives), and M. alcocki(Stebbing, 1920) (South Africa and Mozambique). Ng &Kumar (2015) added one more species, M. tumida Ng &Kumar, 2015, from the west coast of India; and showed
all four were distinct taxa. Similar patterns have also been
observed in some deep water oregoniids (Pleistacantha
Miers, 1879, cf. Ahyong & Ng, 2007; Ng et al., 2017) andmathildellids (Neopilumnoplax Serène in Guinot, 1969, cf.
Ahyong & Ng, 2016), and even in munidopsid squat lobsters(Munidopsis Whiteaves, 1874, cf. Ahyong, 2014).

–

Ambulatory legs short (Fig. 12A, B); distal part of P5 merus
just reaching gastric groove when folded anteriorly (Fig.
12D); dorsal ridge of carpus of cheliped with row of low
sharp tubercles (Fig. 13F); tip of G1 appears bifurcated (Fig.
13K).... Gordonopsis robusta Ng, Padate & Saravanane, 2019(Andaman Sea)
5. Supraorbital margin proportionately wider, pseudorostral spines
relatively short, directed slightly obliquely laterally at angle of
20–30° (Figs. 14B, 15D, 17B).................................................6– Supraorbital margin C-shaped, less wide, pseudorostral spines
long, directed almost 45° obliquely laterally (Figs. 21B,
24B)..........................................................................................7
6. Carapace appears inflated when viewed laterally and frontally(Fig. 15A, B); P2–P4, particularly merus, proportionately shorter(Fig. 16E–G, K, L); outer surface of P4 merus with 1 tubercle
on proximal part (Fig. 16G, I)................ Gordonopsis pacifica
Takeda & Suyama, 2019 (southern Japan)– Carapace appears inflated when viewed laterally and frontally(Fig. 18A, B); P2–P4, particularly merus, proportionately longer(Fig. 19D–F); outer surface of P4 merus unarmed, completely
smooth (Fig. 19F)....... Gordonopsis hera, new species (Papua
New Guinea)
7. Outer margin of each P3 and P4 coxa with 2 long spines
each (Figs. 22I, J, 23B, H); outer surface of P4 merus with 1
perpendicular spine on proximal part.... Gordonopsis phorcys,
new species (Solomon Islands)– Outer margin of each P3 and P4 coxa with 1 spine each (Fig.
26B–D); outer surface of P4 merus unarmed, completely
smooth...... Gordonopsis ceto, new species (South China Sea)

The apparent rarity of Gordonopsis is almost certainly anartefact of collecting—their preferred habitat is probably
too difficult to sample using standard collecting methods(see Ng et al., 2009; Mendoza et al., 2010). The in situ
photographs taken of G. hera (Fig. 20) suggest its preferredhabitat is uneven, hard rocky substrates. The same observation
was made for G. ceto, with the collector noting that theecosystem was extremely difficult to sample using dredges
and trawls due to the very rough terrain. That being said,
the present recognition of eight species in a genus that has
been monotypic since 1995 is indicative of just how poor
our knowledge of the deep-sea fauna is. In fact, until 2019,
the genus was not even known from the western Indian
Ocean and Pacific Ocean!

ACKNOWLEDGEMENTS
Key to species of Gordonopsis

The specimens from Papua New Guinea were collected by
R.V. Alis during the following deep-sea cruises: MADEEP(https://doi.org/10.17600/14004000) and SALOMON 2(https://doi.org/10.17600/4100090). These cruises, PIs Sarah
Samadi, Laure Corbari, and Philippe Bouchet, were operated
by MNHN and Institut de Recherche pour le Développement(IRD) as part of the research programme “Tropical Deep Sea
Benthos”. The exploration of the Papua New Guinea waters in
the programme “La Planete Revisitee” was organised jointly
by MNHN, Pro-Natura International, and IRD, with support
from the National Fisheries Authority of Papua New Guinea.
The organisers acknowledge supporting funding from the
Total Foundation, the Laboratoire d’Excellence Diversités
Biologiques et Culturelles (LabEx BCDiv, ANR-10-LABX0003-BCDiv), and the expedition was endorsed by the New
Ireland Provincial Administration and operated under aMemorandum of Understanding with University of Papua
New Guinea (UPNG). We are also grateful to Chan Tin-Yam(NTOU) and Laure Corbari (MNHN) for their photographsof fresh Gordonopsis. Paul Clark helped us check material
in the NHM and Harry Taylor from its Photographic Unit
kindly took some of the photographs needed. We thankSantanu Mitra (Zoological Survey of India) for trying tohelp us locate the type material of Alcock. Masatsune
Takeda and Hironori Komatsu (NSMT) kindly allowed thefirst author access to the type of G. pacifica. Laure Corbari
and Paula Martin-Lefevre (MNHN) kindly helped with thedata for the French material. Thanks are due to the U.S.
National Oceanographic and Atmospheric Administration
Office of Ocean Exploration and Research for photographs

1. Carapace and pereiopods covered with long dense setae which
obscures surfaces and margins (Fig. 27A–C); distal edge of
dorsal margin of cheliped merus with 1 spine (Fig. 28E, G,
H)...... Gordonopsis velutina, new species (Admiralty Islands)– Carapace and pereiopods glabrous, covered with short setaethat may obscure surface or longer sparser setae that does not
obscure surface (e.g., Figs. 2A–C, 14A–C, 17A–C); distal edgeof dorsal margin of cheliped merus with 2 spines (e.g., Figs.
3F, G, 15G)..............................................................................2
2. Latero-posterior margin of carapace with distinct tubercle orspine (e.g., Fig. 2A); outer margin of P2–P4 coxae unarmed,
smooth......................................................................................3– Latero-posterior margin of carapace with very low tubercle,
barely visible (e.g., Fig. 17A); outer margin of P2–P4 coxae
with a spine or tubercle (may be reduced or absent on someof articles) (e.g., Figs. 18J, K, 22I, J).....................................5
3. Carapace relatively narrower with lateral margins straighter,less convex (Fig. 9B); carpus of cheliped with 1 spine on eachof outer and inner margins, dorsal ridge smooth, unarmed (Fig.
10F, G).......... Gordonopsis alaini, new species (Madagascar)– Carapace longitudinally ovate, with posterior part more globose,lateral margins distinctly convex (e.g., Fig. 2A); carpus ofcheliped with 3 or more spines and spinules on each of outerand inner margins, dorsal ridge not armed with spines or
spinules (e.g., Fig. 3F, G)........................................................4
4. Ambulatory legs long (Figs. 2A, 6A); distal part of P5 merus
extending beyond gastric groove when folded anteriorly (Figs.
4A, 8A); dorsal ridge of carpus of cheliped with row of low
granules (Figs. 3F, G, 7G); tip of G1 subtruncate (Figs. 4H,
8K)....Gordonopsis profundarum (Alcock & Anderson, 1899)(western Indian Ocean)305

Ng & Richer de Forges: Revision of Gordonopsis
of Gordonopsis hera taken in situ in the Tokelau Seamounts;
and to Mary Wicksten for bringing them to our attention.
We are most grateful to Danièle Guinot and Shane Ahyong
for their many important recommendations and suggestions
which have helped the manuscript.

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