Illustrated keys to families and genera of the superfamily Paguroidea (Crustacea: Decapoda: Anomura), with diagnoses of genera of Paguridae

34 Pages·2003·1.1 MB·English

by  P. A. Mclaughlin

Memoirs of Museum Victoria 60(1): 111–144 (2003)
ISSN 1447-2546 (Print) 1447-2554 (On-line)
http://www.museum.vic.gov.au/memoirs
Illustrated keys to families and genera of the superfamily Paguroidea (Crustacea:
Decapoda: Anomura), with diagnoses of genera of Paguridae
PATSYA. MCLAUGHLIN
Shannon Point Marine Center, Western Washington University, 1900 Shannon Point Road, Anacortes, Washington,
98221-9081B, USA([email protected])
Abstract McLaughlin, P.A. 2003. Illustrated keys to families and genera of the superfamily Paguroidea (Crustacea: Decapoda:
Anomura), with diagnoses of genera of Paguridae. In: Lemaitre, R., and Tudge, C.C. (eds), Biology of the Anomura.
Proceedings of a symposium at the Fifth International Crustacean Congress, Melbourne, Australia, 9–13 July 2001.
Memoirs of Museum Victoria60(1): 111–144.
Keys, with illustrations of selected diagnostic characters, are provided for the seven families and 122 genera of the
anomuran Superfamily Paguroidea, commonly known as hermit crabs and king crabs. In addition, abbreviated diagnoses
are presented for the 69 genera presently assigned to the family Paguridae.
Keywords Crustacea, Anomura, Paguroidea, Paguridae, keys, diagnoses
Introduction Holthuis (1993), the category, section, was defined by the third
edition of International Code of Zoological Nomenclature
The interest in, and attendance at, the symposium on Biology of
(1985) as a subdivision of a genus. The fourth edition (1999),
the Anomura at the Fifth International Crustacean Congress,
article 10.4, reaffirms that definition. Although the Code does
2001, indicates the recent focus on this group of decapod
not deal with taxonomic levels above the family group, the use
crustaceans by researchers in several disciplines (e.g. Martin
of the term, section, in other hierarchical levels does not seem
and Abele, 1986, 1988; Tudge and Jamieson, 1991;
appropriate. Therefore, I have adopted the classification of the
Cunningham et al., 1992; Elwood and Neil, 1992; Tudge, 1992,
Anomura proposed by Martin and Davis (2001).
1997a, b; Richter and Scholtz, 1994; Scholtz and Richter, 1995;
To complicate matters even further, there has been an
d’Amato and Corach, 1997; McLaughlin and Lemaitre, 1997,
explosion of new genera over the past two decades, as well as
2001a; Tudge et al., 1998; Morrison and Cunningham, 1999;
additions to and other changes in the hierarchy. Thus it
Förster and Baeza, 2001; Macpherson and Machordom, 2001;
appeared that the presentation of an illustrated set of keys to the
Tudge et al., 2001). Much of this attention has been directed to
families and genera of the Superfamily Paguroidea, would
the morphologically very diverse assemblage commonly
benefit not only new-comers to the field of paguroid syste-
known as hermit crabs and king crabs (Fig. 1). It is not surpris-
matics, but to specialists in other disciplines as well. The user
ing that perusal of some of these references demonstrates the
of the keys contained herein will not be hampered, whether he
lack of agreement among carcinologists on changes in the clas-
or she concurs with the Martin and Davis (2001) classification
sification of this group from 1987 to 2001. Specifically,
or the classification of Forest (1987) and Forest et al. (2000).
because of endophragmal differences, Forest (1987) reinstated
Although within the Diogenidae, several of the larger gen-
the superfamily Coenobitoidea Dana, 1851, that had been sup-
era have been reported on in considerable detail (e.g. Forest,
pressed by McLaughlin (1983), combining it with the super-
1984, 1995; Morgan, 1991; Poupin, 1997; Rahayu and Forest,
family Paguroidea Latreille, 1802, under the Section Paguridea.
1993, 1995), as have the Lithodidae (Dawson and Yaldwyn,
Forest’s (1987) and Forest et al.’s (2000) information, based on
1985; Macpherson, 1988), Pylochelidae (Forest, 1987),
unpublished observations of Mme M. de Saint Laurent,
Coenobitidae (Nakasone, 1988), and Parapaguridae (Lemaitre,
Muséum national d’Histoire naturelle, Paris, apparently was
1989, 1996, 1997, 1999), such is not the case for the family
not sufficiently convincing to Martin and Davis (2001), who in
Paguridae. The few comprehensive studies of this family have
their Updated classification of Recent Crustacea, once again
been, for the most part, regional and/or not easily accessed (e.g.
suppressed the Coenobitoidea and grouped all hermit crab
McLaughlin and Haig,1984, 1989; McLaughlin,1997; Asakura,
families under the Superfamily Paguroidea. As pointed out by
2000, 2001). Therefore, while keys to all of the genera are
112 P.A. McLaughlin
presented, the key to the family Paguridae is supplemented multispinose (having three or more spines on the distal
with an overview of the morphology of the family itself, and margin).
abbreviated diagnoses of the 69 genera (including two Certain species of the Coenobitidae possess calcified, tubu-
subgenera) currently recognised. lar elongations of one or both coxae of pereopod 5 in males;
The key to families is an adaptation of that presented by however, only in males of a number of genera of the Paguridae
McLaughlin and Lemaitre (2001c) when they introduced the are membranous, chitinous, or weakly calcified sexual tubes
new family Pylojacquesidae. Portions of the keys to the genera developed. When present, these structures provide diagnostic
have been adapted from Forest (1984, 1987), Macpherson characters of significant importance. Although most descrip-
(1988), Lemaitre (1996), McLaughlin (1997), Forest and tions have included the orientation of the sexual tube (e.g.
McLaughlin (2000), de Saint Laurent and McLaughlin (2000), across the ventral body surface, toward the exterior, etc.),
McLaughlin and Lemaitre (2001b), Asakura (2001), and heretofore, these tubes have been described only in very gener-
Lemaitre and McLaughlin (in press). In some instances, intra- alised terms, such as long, short, coiled, or with a terminal fila-
generic variability has made it necessary, either to key individ- ment. For the purposes of the key to the Paguridae, four more
ual species that do not conform entirely with particular diag- precisely defined descriptive terms pertaining to tube length,
nostic characters of the genus, or to key the genus more than have been adopted herein, i.e., very short (≤ length of coxa
once. In these instances, the notation (in part) follows the measured on its ventral surface), short, (1–2 coxal lengths),
generic name and author. medium (>2–5 coxal lengths), long (>5 coxal lengths).
Terminology, for the most part, follows that of Forest and Additionally, a very slight protuberance is referred to in the key
McLaughlin (2000) for Coenobitidae and Diogenidae, de Saint as a papilla. Keys to the genera are arranged according to the
Laurent and McLaughlin (2000) for the Paguridae, and key to the families, and do not imply any phylogenetic rela-
Lemaitre (2000) for the Parapaguridae; however, the interpre- tionships. The family Pylojacquesidae McLaughlin and
tation of quadriserial gills employed by Lemaitre (in press) has Lemaitre, 2001c is represented only by the monotypic genus
been used in preference to the more general terminology of Pylojacquesia.
McLaughlin and de Saint Laurent (1998). Enumeration of body
somites follows that of Pilgrim (1973), while that of thoracom- Keys to the families of Paguroidea
eres follows that of Forest et al. (2000). Terminology for the
1. Antennules with upper rami of flagella terminating
Lithodidae follows that of Sandberg and McLaughlin (1998)
bluntly, somewhat “stick-like” (Figs 1a, b, 2h) (semiterres-
for the cephalothorax and its appendages, and that of
trial) . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Coenobitidae
McLaughlin and Paul (2002) for the abdominal tergites. The
— Antennules with upper rami of flagella terminating in
illustrations of key characters provided throughout should pre-
tapered filament, not “stick-like” (Figs 1c–g, k–q, 2i, j, 3a,
clude any necessity to refer to these earlier works to utilise the
c–j, m) (marine, estuarine) . . . . . . . . . . . . . . . . . . . . . .2
keys; however, it must be emphasised that the illustrations are
2. Paired pleopods on abdominal somites 2–5; abdominal
of characters and not necessarily of those of particular genera.
tergites 1–5 well defined, well calcified (Fig. 1c) . . . . . .
As was noted by Forest et al. (2000), the ocular peduncles
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Pylochelidae
are thought to be two or three-segmented. The references to the
— No paired pleopods on abdominal somites 4 and 5; abdom-
ultimate and penultimate segments of the ocular peduncles
inal tergites variable, but most frequently not well calcified
refer to the distal-most and median segments, respectively. The
(Figs 1d–g, i, l–p, 3a) . . . . . . . . . . . . . . . . . . . . . . . . .3
first segments are believed to be represented by a fused seg-
3. Maxilliped 3 generally approximate basally (Figs 2a–c);
ment most frequently reported as the “ocular lobe(s)”, which
chelipeds equal, subequal or unequal, left frequently
usually is unarmed, but may be provided with a pair of small
largest (Figs 1d–g) . . . . . . . . . . . . . . . . . . . .Diogenidae
spines. Sandberg and McLaughlin (1998: 11, fig. 3A) and
— Maxilliped 3 generally widely separated basally (Figs
Forest et al. (2000: 24, figs 1b, 1c) have defined the ocular aci-
2d–f); chelipeds unequal or less frequently subequal, right
cle as a small calcified plate basally on the penultimate pedun-
usually largest (Figs 1i–q) . . . . . . . . . . . . . . . . . . . . . .4
cular segment. In contrast, Boyko and Harvey (1999: 383, fig.
4. Mandible with incisor process mostly corneous, armed
2A) have contended that the ocular acicle is not part of the
with prominent, acute teeth (Fig. 4i); sternite XI distinctly
plate, but only an anterodorsal spine or plate-like extension of
separated from sternite XII by membranous area (Fig. 2l)
the “proximal” peduncular segment. Unfortunately, Boyko and
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Pylojacquesidae
Harvey’s definition applies only to those species where some
— Mandible with incisor process calcareous (Fig. 4j) or with
type of projection is produced from the plate itself, which is not
only mesial edge corneous, lacking acute teeth; sternite XI
the case in all hermit crabs. The “ocular plate” of some
not distinctly separated from sternite XII, usually fused
Pylochelidae is nothing more than the plate itself. To say then
(Fig. 2m) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
that these species lack ocular acicles does not seem justified, as
5. Pereopod 4 developed as normal walking leg (Figs 1i–k;
there is no evidence to suggest a lack of homology between the
3b, 8h); body crab-like; abdomen recurved and carried
simple ocular plate and the ocular plate that has developed a
under cephalothorax (Figs 1j, k) . . . . . . . . . .Lithodidae
projection of one form or another. In the keys presented herein,
— Pereopod 4 not developed as normal walking leg (Figs
the term ocular acicle refers to the entire calcified plate whose
1l–q, 3a); body not crab-like; abdomen usually not
projected portion, if present, may be simple (represented by a
recurved and carried under cephalothorax . . . . . . . . . .6
single spinose process) bifid, (with two distal spines) or
Illustrated keys to the families and genera of Paguroidea 113
6. Exopod of maxilliped 1 with flagellum (Fig. 4m) . . . . . . 6. Abdominal somites, pleopods 3–5, and uropods symmetri-
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Paguridae cal; telson subrectangular, longer than broad, usually with
— Exopod of maxilliped 1 without flagellum (Fig. 4n) . . . . transverse line of flexion delimiting rounded posterior
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Parapaguridae lobes (Fig. 5b); maxilliped 3 without epipod (Fig. 4q)
. . . . . . . . . . . . . . . . . . . . . . . . .Trizocheles Forest, 1987
Key to genera of Coenobitidae — Abdominal somites, pleopods 3–5, and uropods asymmet-
rical; telson variable; maxilliped 3 with epipod (Fig. 4p)
1. Pereopod 4 elongate, chelate; abdomen somewhat flexed
. . . . . . . . . . . . .MixtopagurusA. Milne-Edwards, 1880
(Fig 1a); rostrum well developed . . .BirgusLeach, 1815
— Pereopod 4 short, not chelate; abdomen spirally twisted
(Fig 1b); rostrum obsolete . . . .CoenobitaLatreille, 1829 Key to genera of Diogenidae
1. Well developed arthrobranchs present on arthrodial
Key to genera of Pylochelidae
membranes at bases of cheliped and maxilliped 3;
1. Shield incompletely separated from posterior carapace, pleurobranch present on somite XI (thoracomere 5, above
linea transversalis not apparent medially (Figs 3c, e); pereopod 2) (Fig. 4a) . . . . . . . . . . . . . . . . . . . . . . . . . .2
telson divided into anterior and posterior articulating — Reduced or vestigial arthrobranchs present on arthrodial
plates (Fig. 5a) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2 membranes at bases of cheliped and maxilliped 3; no
— Shield completely separated from posterior carapace, linea pleurobranch present on somite XI (thoracomere 5, above
transversalis clearly apparent medially (Figs 3d, f–h); pereopod 2) (Fig. 4c) . . . . . . . . . . . . . . . . . . . . . . . . . . .
telson not divided into anterior and posterior articulating . . . . . . . . . . . . . . .PseudopaguristesMcLaughlin, 2002
plates (Fig. 5b) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3 2. 14 pairs of gills; pleurobranch present on somite XIV(tho-
2. Shield approximately as long as broad; anterior margin racomere 8, above pereopod 5) (Fig. 4a) . . . . . . . . . . .3
with median concavity and rarely rostral spinule (Fig. 3c); — 13 pairs of gills; no pleurobranch present on somite XIV
corneas always hemispherical . . . . . . . . . . . . . . . . . . . . . (thoracomere 8, above pereopod 5) (Fig. 4b) . . . . . . . .14
. . . . . . . . . . . . . . . .PylochelesA. Milne-Edwards, 1880 3. Endopod of maxillule with well developed external lobe
— Shield distinctly broader than long; anterior margin with (Fig. 4k) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
rounded rostral lobe (Fig. 3e) or with short rostral spine; — Endopod of maxillule without well developed external
corneas reduced or absent (Fig. 3e) . . . . . . . . . . . . . . . . . lobe (Fig. 4l) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
. . . . . . . . . . . . . . . . . . . . . . . . .CheiroplateaBate, 1888 4. Ischium of maxilliped 3 with well developed crista
3. Penultimate segments of ocular peduncles without ocular dentata (Figs 2b–f) . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
acicles developing squamiform or spiniform anterior — Ischium of maxilliped 3 without well developed crista
projections (Figs 3f, h) . . . . . . . . . . . . . . . . . . . . . . . . .4 dentata (Fig. 2a) . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
— Penultimate segments of ocular peduncles with ocular aci- 5. Chelipeds equal or unequal, each with stridulatory
cles each developing triangular or squamiform anterior mechanism developed on mesial face of palm (Fig. 6a) 6
projection (Figs 3d, i, j, m) . . . . . . . . . . . . . . . . . . . . .6 — Chelipeds markedly unequal, left largest; neither with
4. Penultimate segments of ocular peduncles each with well stridulatory mechanism developed on mesial face of palm
developed, rounded or subrectangular plate (Fig. 3f); (Fig. 6b) . . . . .AllodardanusHaig and Provenzano, 1965
telson with pair of oblique lateral incisions, terminal mar- 6. Chelipeds with acute, corneous-tipped spines on carpi and
gin with prominent median cleft; maxilliped 2 without chelae; males often with pleopod 2 paired, endopod well
epipod . . . . . . . . . . . . . . . . . .PomatochelesMiers, 1879 developed, reduced or absent (Fig. 7g) . . . . . . . . . . . . . .
— Penultimate segments of ocular peduncles each with . . . . . . . . . . . . . . . . . . . . . . .StrigopagurusForest, 1995
reduced, narrow, calcified plate (Fig. 3g, h); telson with or — Chelipeds with tubercles or transverse striate on carpi and
without pair of oblique lateral incisions, but never promi- chelae; males without pleopod 2 paired . . . . . . . . . . . .7
nent, terminal margin with or without median cleft; maxil- 7. Chelipeds equal or left larger; carpus and palm with trans-
liped 2 with epipod (Fig. 4o) . . . . . . . . . . . . . . . . . . . . .5 verse striae bordered with fine setae (Fig. 6c); dactyls of
5. Shield as long as broad; rostral spine short, without acces- ambulatory legs equal to or longer than propodi; females
sory ventral spine; ultimate segments of ocular peduncles with unpaired pleopods 2–5 egg-carrying . . . . . . . . . . . . .
spinose, conical and tapered (Fig. 3g); telson rectangular, . . . . . . . . . . . . . . . . . . . . . . . .CiliopagurusForest, 1995
longer than broad, with pair of faint, oblique, lateral — Chelipeds equal, carpus and palm covered with generally
grooves, terminal margin with slight median notch . . . . . blunt tubercles; dactyls of ambulatory legs much shorter
. . . . . . . . . . . . . . . . . . . . . .ParapylochelesAlcock, 1901 than propodi; females with unpaired pleopod 5 non egg-
— Shield broader than long; rostrum very prominent, with carrying . . . . . . . . . . . . . . . .TrizopagurusForest, 1952
accessory ventral subdistal spine; ultimate segments of 8. Chelae symmetrical, together forming operculum (Fig.
ocular peduncles unarmed, basally swollen (Fig. 3h); tel- 6d); uropods symmetrical (Fig. 8j) . . . . . . . . . . . . . . . . .
son subquadrate, slightly broader than long, without pair of . . . . . . . . . . . . . . . . .CancellusH. Milne Edwards, 1836
faint, oblique, lateral grooves, terminal margin entire . . . — Chelae symmetrical or asymmetrical, together not forming
. . . . . . . . . . . . . . . . . . . . . .CancellochelesForest, 1987 operculum; uropods generally asymmetrical . . . . . . . .9
114 P.A. McLaughlin
9. Chelipeds unequal, right distinctly larger . . . . . . . . . . . . process short, broad, triangular, not usually overreaching
. . . . . . . . . . . . . . . . . . . . . .PetrochirusStimpson, 1858 distal margins of corneas . . . . . . . . . . . . . . . . . . . . . . .2
— Chelipeds subequal or unequal, left usually at least — Abdomen generally firm, at least partially calcified, not
slightly larger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10 sac-like; abdominal tergites 3–5 usually well calcified
10. Shield with prominent Y-shaped linea in posterior half (Figs 9f–k), sometimes with median areas membranous;
(Figs 8a, c); posterior carapace primarily membranous; left rostral process well-developed, prominent, truncate or
cheliped slightly to considerably larger than right . . . .11 spiniform (Fig. 8f, h), overreaching distal margins of
— Shield without prominent Y-shaped linea (Fig. 8b, l); corneas (Fig. 3b) . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
posterior carapace well calcified; chelipeds subequal . . . 2. Tergite of abdominal somite 2 divided into median, paired
. . . . . . . . . . . . . . . . . . . .TiseaMorgan and Forest, 1991 lateral and paired marginal plates (Figs 9a, b, d, e, h) .3
11. Rostrum triangular; ocular acicles each with prominent tri- — Tergite of abdominal somite 2 divided into paired lateral
angular or subtriangular acicular projection (Figs 8a, b); and marginal plates, median plate virtually nonexistent
chelipeds and ambulatory legs with ring-like transverse (Fig. 9c) . . . . . . . . . . . . . . . .PlacetronSchalfeew, 1892
striae (Fig. 6e); females with well-developed brood pouch 3. Median plate of abdominal somite 2 well calcified or with
(Fig. 7d) . . . . . . . . . . . . . . . . . . . .AniculusDana, 1852 cluster of calcified granules (Figs 9a, b) . . . . . . . . . . . .4
— Rostrum broadly rounded or obsolete (Fig. 8c, l); ocular — Median plate of abdominal somite 2 membranous (Fig. 9d)
acicles each with subrectangular or subquadrate acicular . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
projection (Fig. 8c); chelipeds and ambulatory legs most 4. Carapace well calcified, dorsal surface and margins armed
often without ring-like transverse striae; females without with numerous subequal spines; rostral process with dorsal
brood pouch . . . . . . . . . . . . . . .DardanusPaul’son, 1875 and lateral spines . . . . . . .AcantholithodesHolmes, 1895
12. Antennal flagella with microscopic setae . . . . . . . . . . . . — Carapace weakly calcified, dorsal surface lacking spines
. . . . . . . . . . . . . . . . . . . . . .PseudopagurusForest, 1952 but setose or pubescent; rostral process simple, lacking
— Antennal flagella with paired, moderate to long setae dorsal and lateral spines (Fig. 1i) . . . . . . . . . . . . . . . . . .
(Fig. 2k) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13 . . . . . . . . . . . . . . . . . . . . . . .HapalogasterBrandt, 1850
13. Chelipeds equal or slightly subequal, similar, dactyls open- 5. Surface of carapace covered with squamose prominences,
ing in generally horizontal plane (Fig. 6f) . . . . . . . . .…. chelipeds tuberculate (Fig. 6p) . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . .IsochelesStimpson, 1858 . . . . . . . . . . . . . . . . . . . . . .OedignathusBenedict, 1895
— Chelipeds unequal and dissimilar; dactyls opening in — Surface of carapace and chelipeds covered with transverse
almost vertical plane (Fig. 6g) .LoxopagurusForest, 1964 ridges or crests (Fig. 6q) . . . . .DermaturusBrandt, 1850
14. Males with pleopods 1 and/or 2 paired, modified as 6. Carapace nearly smooth, unarmed, broader than long and
gonopods (Figs 7a, e, f); females with (Figs 2m, 7b, c) or completely covering ambulatory legs when legs are drawn
without pleopod 1 paired, modified . . . . . . . . . . . . . .15 in against body (Figs 1h, 8h); rostral process broad, com-
— No paired pleopods in either sex . . . . . . . . . . . . . . . .16 pressed, distally truncate (Fig. 1h, 8h) . . . . . . . . . . . . . .
15. Pereopod 4 chelate (Fig. 5t); unpaired pleopods 3–5 occur- . . . . . . . . . . . . . . . . . . . . . .CryptolithodesBrandt, 1848
ring on either right or left side of abdomen . . . . . . . . . . . — Carapace armed with granules, tubercles or spines, not
. . . . . . . . . . . . . . . . . . . . .PaguropsisHenderson, 1888 broader than long and not completely covering ambulatory
— Pereopod 4 not chelate; unpaired pleopods 3–5 occurring legs when legs are drawn in against body; rostral process
on left side of abdomen only . . .PaguristesDana, 1851 variable in shape, but not compressed and distally truncate
16. Chelipeds subequal (Fig. 1f) . . . . . . . . . . . . . . . . . . . .17 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
— Chelipeds unequal, left appreciable larger (Figs 1d, e, g).… 7. Sternite of somite XI (pereopods 2) with deep longitudinal
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18 medial groove or pit (Fig. 2n) . . . . . . . . . . . . . . . . . . .8
17. Ocular acicles bi or multispinose, contiguous or closely set — Sternite of somite XI (pereopods 2) without deep
(Fig. 1f, 8b); posterior margin of abdominal somite 6 longitudinal medial groove or pit . . . . . . . . . . . . . . . .10
unarmed . . . . . . . . . . . . . . . . . .ClibanariusDana, 1852 8. Tergite of abdominal somite 2 subdivided into median and
— Ocular acicles simple, widely separated (Figs 3a, d); paired lateral and marginal plates (Figs 9a, b, d, e, h) .9
posterior margin of abdominal somite 6 spinulose . . . . . — Tergite of abdominal somite 2 usually subdivided into
. . . . . . . . . . . . . . . . . . . . . . . .BathynariusForest, 1989 median and paired marginal plates (Fig. 9i), rarely
18. Rostrum obsolete, roundly subtriangular or broadly round- undivided . . . . . . . . . . . . . . . . .LithodesLatreille, 1806
ed, intercalary rostral process present, well developed, 9. Tergites of abdominal somites 3–5 with only spinulose or
reduced or vestigial (Fig. 3i) . . . . . .DiogenesDana, 1851 spiniform nodules calcified (Fig. 9e) in males; females
— Rostrum moderate to well developed, triangular, with lateral plates of left side well delineated; antennal aci-
intercalary rostral process absent . . .CalcinusDana, 1851 cle usually absent . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . .NeolithodesA. Milne-Edwards and Bouvier, 1894
— Tergites of abdominal somites 3–5 with lateral plates
clearly delineated in both sexes, median plate with nodular
Key to genera of Lithodidae
calcification, accessory marginal plates well developed
1. Abdomen usually soft, membranous, sac-like; abdominal (Figs 9h, i); antennal acicle present . . . . . . . . . . . . . . . . .
tergites 3–5 not fully calcified (Figs 1i, 9a–d) rostral . . . . . . . . . . . . . . . . . . . . . . .ParalithodesBrandt, 1848
Illustrated keys to the families and genera of Paguroidea 115
10. Tergite of abdominal somite 2 subdivided into 3–5 well somite 6 not strongly calcified . . . . . . . . . . . . . . . . . . .6
calcified plates (Figs 9 e, f, h, i) . . . . . . . . . . . . . . . . .11 5. Chela of right cheliped with large spine at base of dactyl
— Tergite of abdominal somite 2 undivided (Figs 9g, j, k) . . (Fig. 6j); males with paired, modified pleopods 1and 2;
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12 abdominal tergite 6 operculate (Fig. 8d) . . . . . . . . . . . . .
11. Tergite of abdominal somite 2 subdivided into 3 plates . . . . . . . . . . . . . .XylopagurusA. Milne-Edwards, 1880
(median and paired laterals) (Fig. 9f) . . . . . . . . . . . . . . . — Chela of right cheliped without large spine at base of
. . . . . . . . . . . . . . . . . . . . . .PhyllolithodesBrandt, 1848 dactyl; males without paired, modified pleopod 1;
— Tergite of abdominal somite 2 subdivided into 5 plates abdominal tergite 6 not operculate . . . . . . . . . . . . . . . . .
(median, paired lateral and marginal) (Figs 9e, h ) . . . . . . . . . . . . . . . . . . . . . . . .LithopagurusProvenzano, 1968
. . . . . . . . . . . . . . . . . . . . . .Rhinolithodes Brandt, 1848 6. Males with (Fig. 7a) or without at least 1 pair of modified
12. Rostral process thick, non-spiniform, hammer-shaped (Fig. pleopods; females with or without pleopod 1 paired,
1j); antennal acicle small, rudimentary; tergites of abdom- modified . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
inal somites 4 and 5 with median plates irregularly — Males with no pleopods paired, modified; females with
calcified . . . . . . . . . . . . .SculptolithodesMakarov, 1934 pleopod 1 paired, modified (Figs 7b, c) . . . . . . . . . . . .9
— Rostral process more or less spiniform; antennal acicle 7. Males with pleopod 2 paired, modified . . . . . . . . . . . . . .
well-developed; tergites of abdominal somites 4 and 5 . . . . . . . . . . . . . . . . . . . . . .TomopaguroidesBalss, 1912
with median plates regularly and entirely calcified (Figs 9f, — Males without pleopod 2 paired, modified . . . . . . . . . .8
g, j, k) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13 8. Right cheliped much larger than left, with massive chela
13. Rostral process formed by anterior process (basal spine) (Fig. 6k) . . . . . . . . .BathypaguropsisMcLaughlin, 1994
and dorsal spine or granule (Fig. 8g) . . . . . . . . . . . . . . . . — Right cheliped only slightly larger than left, chela not
. . . . . . . . . . . . . . . . . . . . .GlyptholithodesFaxon, 1895 massive . . . . . . . . . . . . . .TomopaguropsisAlcock, 1905
— Rostral process formed by anterior process (basal spine) 9. Right cheliped with dactyl opening obliquely (Fig. 6h);
and at least 1 pair of dorsal spines (Fig. 8f) . . . . . . . .14 pereopod 4 semichelate (Figs 5n, p, r, s, v); protopods of
14. Lateral tergal plates of abdominal somite 3 entire (Figs 9f, uropods without elongate spine . . . . . . . . . . . . . . . . . . . .
j); antennal acicle moderately spinulose; walking leg 3 . . . . . . . . . . . . . . . . . . . . . .PylopaguropsisAlcock, 1905
always equal to or longer than carapace width . . . . . . . . — Right cheliped with dactyl opening horizontally (Fig. 6f);
. . . . . . . . . . . . . . . . . . . . . . . . . .ParalomisWhite, 1856 pereopod 4 not semichelate; protopods of uropods each
— Lateral tergal plates of abdominal somite 3 each with small with elongate spine (Fig. 5j) . . . . . . . . . . . . . . . . . . . . . .
accessory plates sundered anteromedially (Figs 9g, k); . . . . . . . . . . . .MunidopagurusA. Milne-Edwards, 1880
antennal acicle extremely spinulose; walking leg 3 never 10. Pleurobranch present on somite XII (thoracomere 7, above
equal to or longer than carapace width . . . . . . . . . . . . . . pereopod 4) (Fig. 4d) . . . . . . . . . . . . . . . . . . . . . . . . .11
. . . . . . . . . . . . . . . . . . . . . .LopholithodesBrandt, 1848 — No pleurobranch present above pereopod 4 . . . . . . . .70
11. Arthrobranchs well developed on maxilliped 3 (Figs 4a,
b, d) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Pylojacquesidae
— Arthrobranchs rudimentary, vestigial or absent on
PylojacquesiaMcLaughlin and Lemaitre, 2001c maxilliped 3 (Fig. 4c) . . . . . . . . . . . . . . . . . . . . . . . .74
See figs 2d, l, 3j, 5w, 7i. 12. Gill structure distally or deeply quadriserial (Figs 4g, h) .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
— Gill structure biserial (Fig. 4f) . . . . . . . . . . . . . . . . . .21
Key to genera of Paguridae
13. Crista dentata of maxilliped 3 with 1 or more accessory
1. Gill formula includes 3 well developed or reduced pleuro- teeth (Figs 2c, f) . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
branchs, 1 each on somites XI–XIII (thoracomeres 5–7, — Crista dentata of maxilliped 3 without accessory tooth
above pereopods 2–4) (Fig. 4b) . . . . . . . . . . . . . . . . . .2 (Figs 2b, d, e) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
— Gill formula includes fewer than 3 pleurobranchs 14. Chelipeds subequal (Fig. 1f, q) . . . . . . . . . . . . . . . . .15
(Figs 4c, d) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10 — Chelipeds distinctly unequal, right largest (Figs 1i–p) . . .
2. Pleurobranchs on somites XI and XII (thoracomeres 5 and . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
6, above pereopods 2 and 3) reduced, rudimentary or 15. Females with paired, modified pleopod 1 (Figs 7b, c) . . .
vestigial . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3 . . . . . . . . . . . . . . . .MichelopagurusMcLaughlin, 1997
— Pleurobranchs on somites XI and XII (thoracomeres 5 and — Females without paired, modified pleopod 1 . . . . . . .16
6, above pereopods 2 and 3) well developed . . . . . . . .4 16. Rostrum triangular; ventral margins of dactyls of
3. Chelipeds markedly unequal; female with paired ambulatory legs each with row of corneous spinules . . . .
gonopores on coxae of pereopod 3 (Fig. 2m) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .PagurodesHenderson, 1888
. . .PropagurusMcLaughlin and de Saint Laurent, 1998 — Rostrum broadly rounded; ventral margins of dactyls of
— Chelipeds subequal; female with single gonopore on coxa ambulatory legs each with row of long stiff bristles . . . .
of left pereopod 3 . . . . . .ChanopagurusLemaitre, 2003 . . . . . . . . . . . . . . . .PseudopagurodesMcLaughlin, 1997
4. No unpaired pleopods in males; tergite of abdominal 17. Males with short (1–2 coxal lengths) left sexual tube
somite 6 strongly calcified . . . . . . . . . . . . . . . . . . . . . .5 (Figs 7m–o, q); females with paired, modified pleopod 1
— Some unpaired pleopods in males; tergite of abdominal (Figs 7b, c) . . . . . . . .TarrasopagurusMcLaughlin, 1997
116 P.A. McLaughlin
— Males with medium (>2–5 coxal lengths) to long (>5 coxal — Telson with terminal margin marked by prominent median
lengths) right sexual tube (Figs 7h, j– m); females without cleft (Figs 5b, c, f–i); ocular peduncles with corneas
paired, modified pleopod 1 . . . . . . . . . . . . . . . . . . . .18 reduced . . . . . . . . .PygmaeopagurusMcLaughlin, 1986
18. Male right sexual tube directed across body ventrally from 31. Females with paired gonopores . . . . . . . . . . . . . . . . .32
right to left (Figs 7j, k, m); female with paired gonopores — Females with single gonopore on coxa of left pereopod 3
(Fig. 2m) . . . . . . . . . . . . . .CestopagurusBouvier, 1897 Anapagridesde Saint Laurent-Dechancé, 1966b (part)
— Male right sexual tube directed toward exterior (Figs 7h, i, 32. Males with 3 or fewer unpaired pleopods . . . . . . . . . .33
l); female with single left gonopore . . . . . . . . . . . . . . . . — Males with 4 unpaired pleopods . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . .. Trichopagurusde Saint Laurent, 1968 . . . . . . . . .Acanthopagurusde Saint Laurent, 1968 (part)
19. Chelipeds subequal, right stronger, but not appreciable 33. Sexual tube very short (<1 coxal length) to moderate (>2–5
longer . .Iridopagurusde Saint Laurent-Dechancé, 1966a coxal lengths) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
— Chelipeds distinctly unequal; right usually appreciably — Sexual tube long (>5 coxal lengths) . . . . . . . . . . . . . .35
longer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20 34. Rostral lobe broadly rounded; pereopod 4 with single row
20. Male with very short (<1 coxal length) to short (1–2 coxal of corneous scales in propodal rasp (Figs 5p, q, u); sexual
lengths) left sexual tube (Figs 7h–o, q); female with paired, tube of moderate length, directed toward exterior . . . . . .
modified pleopod 1 (Figs 7b, c) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .CatapagurusA. Milne-Edwards, 1880
Pagurojacquesia de Saint Laurent and McLaughlin, 2000 — Rostral lobe triangular; pereopod 4 with 2 or more rows of
— Male with moderate (>2–5 coxal lengths) to long corneous scales in propodal rasp (Figs 5n, r, s, v); sexual
(>5 coxal lengths) left sexual tube (Fig. 7p); female tube short or very short, directed anteriorly or posteriorly
without paired, modified pleopod 1 . . . . . . . . . . . . . . . . . . . . .ParapagurodesMcLaughlin and Haig, 1973 (part)
. . . . . . . . . . . . . . . . . . . . . .Turleania McLaughlin, 1997 35. Right sexual tube directed toward exterior and upward
21. Lateral margins of shield each developed into pair of blunt across dorsal body surface . . .HemipagurusSmith, 1881
or spiniform, wing-like processes (Fig. 3k) . . . . . . . . . . . — Right sexual tube directed toward exterior, but not over
. . . . . . . . . . . . . . . . . .PorcellanopagurusFilhol, 1885a dorsal body surface (Figs 7i, l) . . . . . . . . . . . . . . . . . .36
— Lateral margins of shield not developed into pair of blunt 36. Sexual tube terminating in elongate filament (Fig. 7h) . . .
or spiniform, wing-like projections . . . . . . . . . . . . . .22 Nematopaguroides Forest and de Saint Laurent, 1968
22. Males with very short (<1 coxal length) to long sexual (part)
tube(s) (>5 coxal lengths) (Figs 7h–q) . . . . . . . . . . . .23 — Sexual tube not terminating in elongate filament . . . . . .
— Males without sexual tube(s) (Figs 7r, s) . . . . . . . . . .45 . . . . . . . . . . . . . . .Solenopagurusde Saint Laurent, 1968
23. Females with paired, modified pleopod 1 (Figs 7b, c) .24 37. Abdomen reduced (Figs 1i, l, n–p); males without paired or
— Females without paired, modified pleopod 1 . . . . . . .25 unpaired pleopods; females only with unpaired uniramous
24. Carpus of right cheliped strongly produced ventrally (Fig. pleopods 2–4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38
6o); uropods asymmetrical . . . . . . . . . . . . . . . . . . . . . . . — Abdomen well developed (Figs 1d–g,m); males usually
. . . . . . . . . . . . . . . . . .GoreopagurusMcLaughlin, 1988 with some unpaired pleopods; females with unpaired
— Carpus of right cheliped not strongly produced ventrally; biramous pleopods 2–4, usually also with reduced pleopod
uropods symmetrical or nearly so (Fig. 8j) . . . . . . . . . . . . 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39
PylopagurusA. Milne-Edwards and Bouvier, 1891 (part) 38. Rostrum developed as prominent slender spine; pereopod
25. Distinct male sexual tube produced from gonopore on only 5 subchelate (Figs 5w, x) . . . . . . . . . . . . . . . . . . . . . . . .
1 coxa (Fig. 7o, p), papilla present or absent from opposite . . . . . . .AlainopagurusLemaitre and McLaughlin, 1995
gonopore . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26 — Rostrum broad, blunt or subacute, upturned; pereopod 5
— Distinct male sexual tubes produced from gonopores on weakly chelate (Fig. 5y) . . . . . . . . . . . . . . . . . . . . . . . . .
both coxae (Figs 7h–n, q) . . . . . . . . . . . . . . . . . . . . .37 . . . . . . . . . . . . . . .AlainopaguroidesMcLaughlin, 1997
26. Males with left sexual tube . . . . . . . . . . . . . . . . . . . .27 39. Females with paired, modified pleopod 1 . . . . . . . . . . . .
— Males with right sexual tube . . . . . . . . . . . . . . . . . . .31 . .NematopagurusA. Milne-Edwards and Bouvier, 1892
27. Right chela markedly larger than left . . . . . . . . . . . . .28 — Females without paired, modified pleopod 1 . . . . . . .40
— Right chela not markedly larger than left . . . . . . . . . . . . 40. Right sexual tube very short (<1 coxal length) to short (1–2
. . . . . . . . . . . . . . . . . . . . .SpiropagurusStimpson, 1858 coxal lengths) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41
28. Telson with transverse indentation (Figs 5b, c, f–i); male — Right sexual tube long (>5 coxal lengths) . . . . . . . . . . . .
with paired gonopores (Figs 2l, m) . . . . . . . . . . . . . . 29 .Nematopaguroides pusillusForest and de Saint Laurent,
— Telson without transverse indentation (Figs 5d, e, j, k); 1968
male sometimes without right gonopore (Fig. 7p) . . . . . . 41. Antennal acicles each with row of spines (Figs 8b, c, l) . .
. . . . . . . . . . . . . . . . . . .MicropagurusMcLaughlin, 1986 . . . . . . . . . . . . . . . . . . . . .Alloeopagurodes Komai, 1998
29. Telson with terminal margin(s) unarmed (Figs 5e, i, j) 30 — Antennal acicles without row of spines . . . . . . . . . . .42
— Telson with terminal margin(s) armed with spines (Figs 5d, 42. Propodal rasp of pereopod 4 with 2 or more rows of
f, g, k) . . . . . . . . . . . . . . .AnapagurusHenderson, 1886 corneous scales (Figs 5r, s, v) . . . . . . . . . . . . . . . . . . . . .
30. Telson with terminal margin entire (Figs 5d, e); ocular . . . . .ParapagurodesMcLaughlin and Haig, 1973 (part)
peduncles with corneas strongly dilated (Fig. 3m) . . . . . — Propodal rasp of pereopod 4 with 1 row of corneous scales
. . . . . . . . . . . . . . .ForestopagurusGarcía-Gómez, 1994 (Figs 5o, p, q) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43
Illustrated keys to the families and genera of Paguroidea 117
43. Lateral projections prominently produced; telson with — Telson without lateral indentations suggesting division into
rounded posterior lobes, each armed with few long, slen- anterior and posterior portions (Figs 5d, e) . . . . . . . . . . .
der, corneous spines (Fig. 5g) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .EnallopagurusMcLaughlin, 1981
. . . . . . . . . . . . . . . . . . .IcelopagurusMcLaughlin, 1997 55. Chela of right cheliped subovate to subcircular, margins
— Lateral projections not prominently produced; telson with unarmed, weakly tuberculate or minutely crenulate and/or
obtusely subtriangular posterior lobes, each armed with serrate, but never armed with prominent, blunt or acute
few minute spinules . . . . . . . . . . . . . . . . . . . . . . . . . .44 spines (Figs 6i, o) . . . . . . . . . . . . . . . . . . . . . . . . . . .56
44. Coxa of right pereopod 5 in males with short sexual tube, — Chela of right cheliped variable, margins armed with
coxa of left pereopod 5 usually without papilla; females prominent, blunt or acute spines or tubercles (Figs 6l, m)
with paired gonopores . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57
. . . . . . . . .Acanthopagurusde Saint Laurent, 1968 (part) 56. Pereopod 4 with large, very prominent preungual process
— Coxa of right pereopod 5 in males with very short sexual at base of claw (Fig. 5p, s, u) . . . . . . . . . . . . . . . . . . . . .
tube, coxa of left pereopod 5 with or without papilla; . . . . . . . . . . . . . . . . . . . .PhimochirusMcLaughlin, 1981
females with single left gonopore . . . . . . . . . . . . . . . . . . — Pereopod 4 without large, very prominent preungual
Anapagridesde Saint Laurent-Dechancé, 1966 (part) process at base of claw (Figs 5o, q, r) . . . . . . . . . . . . . . .
45. Females with paired, modified pleopod 1 . . . . . . . . . .46 PylopagurusA. Milne-Edwards and Bouvier, 1891 (part)
— Females without paired, modified pleopod 1 . . . . . . .60 57. Dactyl and fixed finger of left chela excavated ventrally,
46. Abdomen reduced; males without unpaired pleopods; spoon-shaped . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
females with unpaired pleopods 2–4 . . . . . . . . . . . . . . . . TomopagurusA. Milne-Edwards and Bouvier, 1893 (part)
. . . . .ProtoniopagurusLemaitre and McLaughlin, 1996 — Dactyl and fixed finger of left chela not excavated
— Abdomen not reduced; males with some unpaired ventrally, not spoon-shaped . . . . . . . . . . . . . . . . . . . .58
pleopods; females with unpaired pleopods 2–5 . . . . .47 58. Right chela circumscribed by row of dorsomesial, dorso-
47. Right cheliped markedly elongate . . . . . . . . . . . . . . . . . . proximal and dorsolateral marginal spines (Fig. 6l); left
. . . . . . . . . . . . . . . . . . . . .CeratopagurusYokoya, 1933 cheliped with rotation of propodal-carpal articulation 45°-
— Right cheliped not markedly elongate . . . . . . . . . . . .48 90°from horizontal plane . . . . . . . . . . . . . . . . . . . . . . . .
48. Protopods of uropods prominently produced posteriorly . . . . .Lophopagurus(Australeremus) McLaughlin, 1981
(Fig. 5j); dorsal surface of right chela commonly with — Right chela not circumscribed by row of dorsomesial,
characteristic covering of mushroom-shaped tubercles . . dorsoproximal and dorsolateral marginal spines; left
. . . . . . . . . . . . . . . . . .AgaricochirusMcLaughlin, 1981 cheliped with rotation of propodal-carpal articulation
— Protopods of uropods not prominently produced posterior- much less than 45°from horizontal plane . . . . . . . . .59
ly; dorsal surface of right chela usually without character- 59. Left chela with midline elevated into prominent keel or
istic covering of mushroom-shaped tubercles . . . . . . .49 crest (Fig. 6n) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
49. Spines on dorsal surfaces of chelae with basal rosettes . . . . .Lophopagurus (Lophopagurus) McLaughlin, 1981
(Fig. 6m) . . . . . . . . . . .Rhodochirus McLaughlin, 1981 — Left chela with midline sometimes elevated, but not into
— Spines on dorsal surfaces of chelae without basal rosettes prominent keel or crest . . . . . .HaigiaMcLaughlin, 1981
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50 60. Antennal peduncle with prominent, hooked spine at lat-
50. Propodal rasp of pereopod 4 with more than one row of erodistal margin of segment 1 (Fig. 8k) . . . . . . . . . . . . .
corneous scales (Figs 5r, s, v) . . . . . . . . . . . . . . . . . . 51 . . . . . . . . . . . . . .Tomopagurus wassiMcLaughlin, 1981
— Propodal rasp of pereopod 4 with one row of corneous — Antennal peduncle without prominent, hooked spine at lat-
scales (Figs 5p, q, u) . . . . . . . . . . . . . . . . . . . . . . . . . 53 erodistal margin of segment 1 . . . . . . . . . . . . . . . . . .61
51. Left chela triangular or subtriangular in cross-section, 61. Ultimate segment of antennular peduncles with very long
dactyl and fixed finger not dorsoventrally flattened . .52 seta provided with long paired setules (Fig. 2i); abdomen
— Left chela not triangular or subtriangular in cross-section, elongate, generally straight . . . . . . . . . . . . . . . . . . . . . . .
dactyl and fixed finger dorsoventrally flattened . . . . . . . . . . . . .Pagurus imafukui McLaughlin and Konishi, 1994
. . . . . . . . . . . . . . . . .ManucomplanusMcLaughlin, 1981 — Ultimate segment of antennular peduncles without very
52. Telson with lateral indentations suggesting division into long seta provided with long paired setules; abdomen
anterior and posterior portions (Figs 5b, f-i) . . . . . . . . . . variable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .62
. . . . . . . . . . . . . . . . . .AnisopagurusMcLaughlin, 1981 62. Coxae of male pereopod 5 asymmetrical (Figs 7s, t) .63
— Telson without lateral indentations suggesting division into — Coxae of male pereopod 5 generally symmetrical (Figs
anterior and posterior portions (Figs 5d, e) . . . . . . . . . . . 2m, 7r) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .64
. . . . . . . . . . . . . . .EnallopaguropsisMcLaughlin, 1981 63. Male with 3 unpaired pleopods; coxa of right pereopod 5
53. Ocular acicles simple (Figs 3a, m, 8a); coxae of male produced, gonopore masked by tuft of long, stiff setae
pereopods 5 symmetrical . . . . . . . . . . . . . . . . . . . . . .54 (Fig. 7s) . . . . . . . . . . . . . . . . . . .PagurixusMelin, 1939
— Ocular acicles multispinose (Fig 8e); coxae of male — Male without pleopods; coxa of left pereopod 5 produced,
pereopods 5 asymmetrical . . . . . . . . . . . . . . . . . . . . . . . . gonopore masked by tuft of long, stiff setae (Fig. 7t) . . .
. . . . .PylopaguridumMcLaughlin and Lemaitre, 2001b . . . . . . . . . . . . . . . . . . . . . . . . .PaguridiumForest, 1961
54. Telson with lateral indentations suggesting division into 64. Males with both coxae of pereopod 5 produced, gonopores
anterior and posterior portions (Figs 5b, f–i) . . . . . . .55 each masked by tuft of long, stiff setae; telson with
118 P.A. McLaughlin
markedly concave terminal margin, outer angles acute, — Rostrum not strongly deflected downward, without
with extremely prominent pair of spines adjacent to prominent epirostral spine . . . . . . . . . . . . . . . . . . . . .75
median cleft (Fig. 5h) . . . . . . . . . . . . . . . . . . . . . . . . . . . 75. Male sexual tube with terminal fringe of dense curved
. . . . . . . . . .DiacanthurusMcLaughlin and Forest, 1997 setae; no preungual process at base of claw of pereopod 4
— Males without coxae of pereopods 5 produced; telson . . . . . . . . . . . . . . . . . .EnneopagurusMcLaughlin, 1997
without markedly concave terminal margin, outer angles — Male sexual tube without terminal fringe of dense curved
variable, without extremely prominent pair of spines setae; preungual process developed at base of claw of pere-
adjacent to median cleft . . . . . . . . . . . . . . . . . . . . . . .65 opod 4 . . . . . . . . . .EnneobranchusGarcía-Gómez, 1988
65. Telson with distinct transverse indentation (Figs 5b,c, f–i)
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66
— Telson without distinct transverse indentation (Figs 5d,
Key to genera of Parapaguridae
e, j) . . . . . . . . . . . .DiscorsopagurusMcLaughlin, 1974
66. Posterior portion of cephalothorax, at least in part calcified 1. Corneas present . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
(Fig. 1l); abdomen reduced LabidochirusBenedict, 1892 — Corneas absent (Fig. 8l) . . . . . . . . . . . . . . . . . . . . . . . . .
— Posterior portion of cephalothorax membranous; abdomen . . . . . . . . . . . . . . .Typhlopagurusde Saint Laurent, 1972
well developed (Figs 1d–g, m) . . . . . . . . . . . . . . . . . .67 2. Rostrum short, not exceeding ocular peduncles . . . . . .3
67. Left chela with pronounced counterclockwise torsion; — Rostrum long, often exceeding ocular peduncles (Fig. 1q)
pereopods 4 each with prominent circular “type AP4 struc- . . . . . . . . . . . . . . . . . . . . . . . . . .ProbeebeiBoone, 1926
ture” on lateral face of dactyl (Fig. 5v) . . . . . . . . . . . . . . 3. Ocular acicles distinctly developed (Figs 8a–c, e, l) . . .4
. . . . . . . . . . . . . . . . . . . . . .ElassochirusBenedict, 1892 — Ocular acicles weakly developed or obsolete (Fig. 1p)
— Left chela without pronounced counterclockwise torsion; . . . . . . . . . . . . . . . . . . . . . . . .TylaspisHenderson, 1885
pereopod 4 without prominent circular “type A P4 4. Posterior carapace mostly membranous; unpaired left
structure” on lateral face of dactyl . . . . . . . . . . . . . . .68 pleopods 3–5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
68. Uropods generally asymmetrical; abdomen spirally flexed — Posterior carapace calcified; asymmetrically paired
. . . . . . . . . . . . . . . . . . . . . . . . .PagurusFabricius, 1775 pleopods 3–5 . . . . . . . . .BivalvopagurusLemaitre, 1993
— Uropods generally symmetrical; abdomen not spirally 5. Shield about as broad or broader than long; rostrum
flexed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69 bluntly triangular or broadly rounded; abdomen flexed .6
69. Males with 3 unpaired pleopods; females with 4 unpaired — Shield distinctly longer than broad; rostrum acutely
pleopods . . . . . . . . . . . . . .OrthopagurusStevens, 1927 triangular; abdomen straight . . . . . . . . . . . . . . . . . . . . . .
— Males without unpaired pleopods; females with 3 unpaired . . . . . . . . . . . . . . . . . . . .TsunogaipagurusOsawa, 1995
pleopods . . . . . . . . . . . . . . . . . . .PagurittaMelin, 1939 6. Shield distinctly broader than long; dactyls of ambulatory
70. Crista dentata with 3 or 4 very large, widely-spaced spine- legs straight or nearly so; corneas strongly dilated (Fig.
like teeth (Fig. 2g) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3m); pleopod 2 of male with short exopod and strongly
. . . . . .ScopaeopagurusMcLaughlin and Hogarth, 1998 twisted distal segment (Fig. 7e) . . . . . . . . . . . . . . . . . . .
— Crista dentata well developed or reduced, but never with . . . . . . . . . . . . . . . . . . . .StrobopagurusLemaitre, 1989
only 3 or 4 widely-spaced spine-like teeth . . . . . . . . .71 — Shield about as broad as long; dactyls of ambulatory legs
71. Ambulatory dactyls paddle-shaped (Fig. 1n); females with curved; corneas moderately or weakly dilated; pleopod 2
paired gonopores; males with right sexual tube … . . . . . . of male lacking exopod and distal segment not twisted
. . . . . . . . . . . . . .OstraconotusA. Milne-Edwards, 1880 (Fig. 7f) (rarely absent) . . . . . . . . . . . . . . . . . . . . . . . .7
— Ambulatory dactyls not paddle-shaped; females with sin- 7. Vestigial pleurobranch present on each side of somite XIV
gle left gonopore; males with pair of sexual tubes . . .72 (thoracomere 8, above pereopod 5) (Fig. 4e) . . . . . . . . . .
72. Lateral margins of shield not drawn out into 3 prominent . . . . . . . . . . . . . . . . . . . . . . . .SympagurusSmith, 1883
lobes; males with some unpaired pleopods; females with- — Vestigial pleurobranch absent on each side of somite XIV
out paired, modified pleopod 1 . . . . . . . . . . . . . . . . . .73 (thoracomere 8, above pereopod 5) . . . . . . . . . . . . . . .8
— Shield with lateral margins each drawn out into 3 promi- 8. Epistomial spine straight (Fig. 8m) or absent . . . . . . . .9
nent lobes (Fig. 3l); males without unpaired pleopods; — Epistomial spine strongly curved upward . . . . . . . . . . . .
females with paired, modified pleopod 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .OncopagurusLemaitre, 1996
. . . . . . . . . . . . . . . . . . . .SolitariopagurusTürkay, 1986 9. Gill structure bi- or quadriserial (Figs 4f–h); segment 4
73. Males with 3 unpaired pleopods; left sexual tube partially of antennal peduncle armed with dorsodistal spine;
obscured by tufts of setae . . . . . . . . . . . . . . . . . . . . . . . . length of ocular peduncles, including corneas, at least half
. . .CatapaguroidesA. Milne-Edwards and Bouvier, 1892 length of shield . . . . . . .ParagiopagurusLemaitre, 1996
— Males with 4 unpaired pleopods . . . . . . . . . . . . . . . . . . . — Gill structure quadriserial (Figs 4g, h); segment 4 of anten-
. . . . . . . . . . . . . . . .Decaphyllusde Saint Laurent, 1968 nal peduncle unarmed; length of ocular peduncles, includ-
74. Rostrum strongly deflected downward, with prominent ing corneas, less than half length of shield (except
epirostral spine (Fig. 8i) . . . . . . . . . . . . . . . . . . . . . . . . . Parapagurus bouvieriStebbing, 1910) . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . .EnneophyllusMcLaughlin, 1997 . . . . . . . . . . . . . . . . . . . . . . . .ParapagurusSmith, 1879
Illustrated keys to the families and genera of Paguroidea 119
PaguridaeLatreille, 1802 AgaricochirusMcLaughlin, 1981
In the abbreviated generic diagnoses presented, characters Diagnosis.Gills biserial, 11 pairs. Rostrum obtusely triangular.
common to the family are not repeated. Statements simply of Ocular acicles simple. Crista dentata with 1 accessory tooth.
pleopod number refer to the unpaired left pleopods. The Right chela generally ovate, armature usually as mushroom-
expression “distally divided” (formerly “intermediate”) is used shaped tubercles. Carpi of ambulatory legs lacking dorsodistal
to indicate gill lamellae (Fig. 4g) that while not deeply or spine. Sternite of somite XII (thoracomere 6, pereopods 3) with
completely subdivided, do show partial distal cleavage or anterior lobe absent, reduced and styliform, or small and sub-
distinct indentations. Genera are arranged in alphabetical quadrate. Pereopod 4 semichelate; propodal rasp with several
order. rows of corneous scales; preungual process small. Coxae of
male pereopods 5 occasionally with slight papilla protruding
Diagnosis. Cephalothorax usually with only shield weakly to
from one or both gonopores; pleopods 3–5. Female with paired,
strongly calcified; rostrum produced as median projection or
modified pleopod 1; pleopods 2–5. Uropods symmetrical or
rounded lobe; lateral projections usually well developed. Gills
nearly so, protopods produced posteriorly. Telson with median
bi- or quadriserial phyllobranchia, 8–13 pairs. Ocular pedun-
cleft usually broadly U-shaped, posterior lobes usually sym-
cles with penultimate segments each provided with acicle.
metrical, terminal margins unarmed. Type species:
Antennal acicles most commonly with only terminal spine.
Pylopagurus boletiferA. Milne-Edwards and Bouvier, 1893.
Maxillipeds 3 separated by moderate to broad sternal plate;
ischium usually with well developed crista dentata, sometimes
AlainopaguroidesMcLaughlin, 1997
reduced, with or without 1 or more accessory teeth. Chelipeds
unequal or subequal, right generally larger. Ambulatory legs Diagnosis. Gills biserial, 11 pairs. Anterior carapace vaulted
with dactyls and propodi usually similar from right to left, and generally well calcified, with anterolateral regions slightly
occasionally dissimilar; dactyls usually with ventral row of cor- depressed. Rostrum obtusely triangular. Ocular acicles simple.
neous spines; carpi usually armed with at least dorsodistal Crista dentata somewhat reduced, 1 accessory tooth. Chelipeds
spine. Pereopod 4 usually semichelate, sometimes subchelate, subequal; right stronger, but not necessarily longer. Sternite of
infrequently chelate or simple; preungual process present or somite XII (thoracomere 6, pereopods 3) with narrow, trans-
absent at base of claw; rarely circular sensory structure (type A verse anterior lobe. Pereopod 4 weakly semichelate, propodal
P4 structure, cf. McLaughlin, 1974) on lateral face of dactyl. rasp rudimentary; prominent tubular preungual process.
Fifth pereopods usually chelate, occasionally subchelate. Abdomen reduced; tergal plates of somites 2–5 sometimes very
Males usually with paired gonopores on coxae of pereopod 5, faintly delineated. Male with moderate, stout sexual tube on
occasionally only with single left gonopore; membranous, coxa of right pereopod 5, left often with very short tube; no
chitinous, or very weakly calcified sexual tube frequently unpaired pleopods. Female pleopods 2–4. Uropods gener-
developed in conjunction with gonopore on one or both coxae; ally symmetrical. Telson with terminal margins narrowly to
usually without, but occasionally with pleopods 1 and/or 2 broadly oblique. Type species: Alainopaguroides lemaitrei
paired and modified; with or without unpaired left pleopods on McLaughlin, 1997.
abdominal somites 3–5 or 2–5. Females usually with paired
gonopores on coxae of pereopod 3, occasionally only single left Alainopagurus Lemaitre and McLaughlin, 1995
gonopore; often without, but frequently with, pleopod 1 paired
Diagnosis. Gills biserial, 11 pairs. Anterior carapace vaulted
and modified; with unpaired left pleopods on somites 2–5, or
and generally well calcified, with anterolateral regions distinct-
less frequently, 2–4. Uropods usually asymmetrical, occasion-
ly globular. Ocular acicles multispinose. Crista dentata with 1
ally symmetrical. Telson usually with lateral indentations
accessory tooth. Right cheliped stronger, but not markedly
separating anterior and posterior portions; posterior lobes
longer. Sternite of somite XII (thoracomere 6, pereopods 3)
usually separated by median cleft. Type genus: Pagurus
with narrow, transverse anterior lobe. Pereopod 4 subchelate,
Fabricius, 1775.
propodal rasp with 1 row of corneous spines; no preungual
process. Pereopod 5 subchelate. Male with stout, moderate sex-
Acanthopagurusde Saint Laurent, 1968
ual tubes of approximately equal length on coxae of both pere-
Diagnosis. Gills biserial, 11 pairs. Rostrum obtusely and round- opods 5, each with long setae mesially and terminally; no
ly triangular. Ocular acicles simple. Crista dentata with 1 acces- unpaired pleopods. Female with single gonopore opening pos-
sory tooth. Right cheliped much stronger than left. Sternite of teriorly on coxa of left pereopod 3; pleopods 2–4 only.
somite XII (thoracomere 6, pereopods 3) with subsemicircular Abdomen reduced; tergal plate of somite 2 weakly delineated;
anterior lobe. Pereopod 4 semichelate; propodal rasp with 1 tergal plates of somites 3–5 clearly defined, chitinous or very
row of corneous scales; no preungual process. Male with short, weakly calcified. Uropods symmetrical. Telson with terminal
massive sexual tube on right coxa of pereopod 5, directed margin entire. Type species: Alainopagurus crosnieri Lemaitre
obliquely toward midline; left coxa without sexual tube, or pos- and McLaughlin, 1995.
sibly with small papilla protruding from gonopore; pleopods
AlloeopagurodesKomai, 1998
3–5. Female with pleopods 2–5. Telson with terminal margins
oblique. Type species: Anapagurus ?dubiusA. Milne-Edwards Diagnosis. Gills biserial, 11 pairs. Ocular acicles simple.
and Bouvier, 1900. Rostrum prominent, lateral projections reduced. Antennal
120 P.A. McLaughlin
acicles each with row of spines on mesial surface. Crista den- propodal-carpal articulation approximately 30˚ from perpendi-
tata with 1 accessory tooth. Right cheliped elongate in large cular; left cheliped with propodal-carpal articulation with
males. Sternite of somite XII (thoracomere 6, pereopods 3) 30–60˚ counterclockwise rotation. Sternite of somite XII
with subrectangular anterior lobe, margin spinose. Pereopod 4 (thoracomere 6, pereopods 3) with subrectangular anterior lobe.
semichelate; propodal rasp with 1 row of corneous scales; no Pereopod 4 semichelate; propodal rasp of 1or more, sometimes
preungual process. Right coxa of pereopod 5 in male with incomplete, rows of corneous scales; no preungual process.
short, mesially directed sexual tube; coxa of left with very short Male with pleopods 2–5. Female with pleopods 2–5. Telson
sexual tube; pleopods 3–5. Female with pleopods 2–5. Telson with terminal margins oblique. Type species: Bathypaguropsis
with terminal margins rounded. Type species: Alloeopagurodes yaldwyniMcLaughlin, 1994.
spiniaciculaKomai, 1998.
CatapaguroidesA. Milne-Edwards and Bouvier, 1892
Anapagridesde Saint Laurent-Dechancé, 1966
Diagnosis. Gills biserial, 10 pairs, no pleurobranch on somite
Diagnosis. Gills biserial, 11 pairs. Rostrum triangular. Ocular XIII (thoracomere 7, above arthrobranchs of pereopod 4).
acicles simple. Crista dentata with 1 accessory tooth. Chelipeds Rostrum as rounded lobe. Ocular acicles simple. Crista dentata
unequal; right appreciably larger. Sternite of somite XII (thora- more or less reduced, no accessory tooth. Chelipeds unequal,
comere 6, pereopods 3) with anterior lobe subrectangular to right appreciably stronger. Sternite of somite XII (thoracomere
subcircular. Pereopod 4 semichelate, propodal rasp with 1 row 6, pereopods 3) with roundly rectangular anterior lobe.
of corneous scales. Male with short, posteriorly directed sexu- Pereopod 4 semichelate; propodal rasp with 1 row of corneous
al tube on right coxa of pereopod 5; pleopods 3–5. Female with scales; no preungual process. Pereopod 5 semichelate. Male
single gonopore on coxa of left pereopod 3; pleopods 2–5. with moderate to long sexual tube on coxa of right pereopod 5,
Telson with terminal margins straight to oblique. Type species: directed from right to left under thorax and recurved anteriorly;
Eupagurus (Spiropagurus) facetusMelin, 1939. coxa of left with very short or short tube concealed between 2
thick tufts of sternal setae; pleopods 3–5. Female with single
Anapagurus Henderson, 1886 gonopore on coxa of left pereopod 3; pleopods 2–5. Telson with
terminal margins straight or oblique. Type species:
Diagnosis. Gills biserial, 11 pairs. Rostrum as rounded lobe.
Catapaguroides micropsA. Milne-Edwards and Bouvier, 1892.
Ocular acicles simple; ocular lobes unarmed or with pair of
spines. Crista dentata with 1 accessory tooth. Chelipeds gross-
CatapagurusA. Milne-Edwards, 1880
ly unequal, right much larger. Sternite of somite XII (thora-
comere 6, pereopods 3) with subrectangular anterior lobe. Diagnosis.Gills biserial, 11 pairs. Rostrum as broadly rounded
Pereopod 4 semichelate; propodal rasp with 1 row of corneous lobe. Ocular acicles simple. Crista dentata somewhat reduced,
scales; no preungual process. Coxa of left pereopod 5 in male with 1 accessory tooth. Chelipeds elongate, unequal, right
with short to moderate sexual tube directed toward exterior and stouter than left. Sternite of somite XII (thoracomere 6, pere-
often curved over abdomen dorsally; coxa of right sometimes opods 3) with subrectangular anterior lobe. Pereopod 4 semi-
with short sexual tube; pleopods 3–5. Females with pleopods chelate; propodal rasp with 1 row of corneous scales; preungual
2–5. Telson with terminal margins generally oblique. Type process prominent. Coxa of right pereopod 5 of male with mod-
species: Pagurus laevisBell, 1846. erate sexual tube, curving toward exterior over lateral side of
abdomen, left coxa occasionally with very slightly protruded
AnisopagurusMcLaughlin, 1981 papilla; pleopods 3–5. Female with pleopods 2–4 or 2–5.
Telson with terminal margins oblique. Type species:
Diagnosis. Gills biserial, 11 pairs. Rostrum well developed or
Catapagurus sharreri A. Milne-Edwards, 1880. (Generic
reduced to rounded lobe. Ocular acicles simple or multispinose.
diagnosis restricted by Asakura, 2001)
Crista dentata with 1 accessory tooth. Right chela usually sub-
operculate. Left cheliped with propodal-carpal articulation
Ceratopagurus Yokoya, 1933
rotated 0–45˚ from perpendicular. Sternite of somite XII (tho-
racomere 6, pereopods 3) with subrectangular to subtriangular Diagnosis.Gills biserial, 11 pairs. Rostrum as broadly rounded
anterior lobe. Pereopod 4 semichelate; propodal rasp with 3 or lobe. Ocular acicles simple. Crista dentata with 1 accessory
4 rows of corneous scales; preungual process usually moder- tooth. Chelipeds subequal, similar, moderately long and slen-
ately well developed. Males with pleopods 3–5. Females with der. Sternite of somite XII (thoracomere 6, pereopods 3) not
pleopod 1 paired, modified; pleopods 2–5. Telson with terminal known. Pereopod 4 semichelate; propodal rasp with several
margins rounded, sometimes somewhat excavated. Type rows of corneous scales. Male with pleopods 3–5. Female with
species: Pylopagurus bartletti A. Milne-Edwards, 1880 pleopod 1 paired, modified; pleopods 2–5. Telson unknown.
Type species: Ceratopagurus pilosimanusYokoya, 1933.
BathypaguropsisMcLaughlin, 1994
CestopagurusBouvier, 1897
Diagnosis. Gills quadriserial, 13 pairs. Rostrum well devel-
oped. Ocular acicles simple. Crista dentata with 1 accessory Diagnosis.Gills distally quadriserial, 11 pairs. Rostrum promi-
tooth. Right cheliped massive, chela operculate or nearly so; nent, acutely triangular. Ocular acicles simple. Crista dentata