DROMIINAE de Haan, 1833

Guinot, Danièle & Tavares, Marcos, 2003, A new subfamilial arrangement for the Dromiidae de Haan, 1833, with diagnoses and descriptions of new genera and species (Crustacea, Decapoda, Brachyura), Zoosystema 25 (1), pp. 43-129 : 49-58

Subfamily DROMIINAE de Haan, 1833 n. status

Dromies H. Milne Edwards, 1832: 302, sq.

Dromiacea de Haan, 1833 pro parte: ix, x; 1839 pro parte: 102.

Dromiens – H. Milne Edwards 1837 pro parte: 167, 168.

Dromites – Lucas 1840 pro parte: 112.

Dromiidae – Ortmann 1892: 541, 543. — Barnard 1950: 306. — Holthuis 1962: 56. — Manning & Holthuis 1981: 11 [Name 356 on Official List]. — McLay 1993 pro parte: 111-251. — Guinot et al. 1994: 255, fig. 7. — Hendrickx 1995 pro parte: 127. — Ng 1998: 1056, 1063, 1085. — Ng et al. 2000 pro parte: 156; 2001 pro parte: 5. — Melo & Campos 1999 pro parte: 274. — Martin & Davis 2001 pro parte: 49, 74. — Chen & Haibao 2002 pro parte: 73, 541.

TYPE GENUS. — Dromia Weber, 1795 (type species: Cancer personatus Linnaeus, 1758 by subsequent designation under the Plenary Powers of the International Commission on Zoological Nomenclature, Opinion 688, see Holthuis 1962). Name 1568 on Official List. GENERA INCLUDED. — Ascidiophilus Richters, 1880 ; Alainodromia McLay, 1998 ; Austrodromidia McLay, 1993 ; Barnardromia McLay, 1993 ; Conchoecetes Stimpson, 1858 ; Cryptodromia Stimpson, 1858 ; Cryptodromiopsis Borradaile, 1903 ; Desmodromia McLay, 2001 ; Dromia Weber, 1795 ; Dromidia Stimpson, 1858 ; Dromidiopsis Borradaile, 1900 ; Epigodromia McLay, 1993 ; Epipedodromia André, 1932 ; Eudromidia Barnard, 1947 ; Exodromidia Stebbing, 1905 ; Fultodromia McLay, 1993 ; Haledromia McLay, 1993 ; Hemisphaerodromia Barnard, 1954 ; Homalodromia Miers, 1884 ; Lamarckdromia n. gen.; Lauridromia McLay, 1993 ; Lewindromia n. gen.; Mclaydromia n. gen.; Moreiradromia n. gen.; Paradromia Balss, 1921 ; Petalomera Stimpson, 1858 ; Platydromia Brocchi, 1877 ; Pseudodromia Stimpson, 1858 ; Speodromia Barnard, 1947 ; Stebbingdromia n. gen. (uncertain status); Sternodromia Forest, 1974 ; Stimdromia McLay, 1993 ; Takedromia McLay, 1993 ; Tunedromia McLay, 1993 .

DESCRIPTION

Carapace varying from longer than wide, as wide as long to much wider than long; convex, clearly subdivided into anterior and posterior portions; dorsal regions rather well-defined and variously ornamented; lateral margins usually rounded. Front variously shaped, often with median rostrum and two pseudorostral teeth, one at each side of rostrum. Supra- and infraorbital margins usually toothed and separated from each other by deep notch. Orbits small, rather circular, orient- ed more or less horizontally. Ocular stalk rather short, more or less thick, diversely shaped. Thoracic sternum narrow. Gynglymes of thoracic sternites 1-3 largely spaced from each other, situated at lower plane. Sternite 4 forming plate in contact with bases of the mxp3 or separated from mxp3 by sternite 3 when exposed. Episternites 4 and 5 more or less narrow, with gynglymes of P1 and P 2 in almost terminal location. Female sternal sutures 7/8 long (except Stebbingdromia n. gen.), and apertures of spermathecae opening into thoracic sternum far beyond level of coxa of P3 (except Stebbingdromia n. gen.), apart or together, on two tubercules or on central prominence; apertures usually showing as minute pores at extremities of sutures 7/8, exceptionally as slits ( Sternodromia ). Anterior part of thoracic sternite 4 and episternites 4 and 5 either completely covered or left diversely uncovered by male abdomen when folded. Deep sterno-coxal depressions usually present. Male abdomen length variable, when flexed attaining the coxa of mxp3 or diverse levels of the P1 coxa. Male abdomen generally narrow, often without pleural parts recognizable, or sometimes broader; all segments free (exceptionally segment 5 and 6 more or less fused), segment 6 not noticeably extended laterally. Male Pl3-Pl5 usually absent, but sometimes vestigial. In males and immature females, uropods showing as salient calcified dorsal plates, often playing role in abdominal holding, or as ventral plates or lobes (see Patterns of uropods and vestigial male pleopods 3-5). Mature female uropods generally more horizontal, not so salient. Male telson usually short, variously shaped. Holding of male and immature female abdomens variable, usually efficient, a variable number of pereopods being involved. Chelipeds with or without epipod; podobranch absent. P2 and P3 often lobed or nodose; propodus short, lacking distal propodal spine (except Stebbingdromia n. gen.); dactylus curved and armed with spines on inner border. P4 and P5 reduced, similar in size and shape (rare exception: Conchoecetes ), shorter than preceding ones, oriented subdorsally (P4) or dorsally (P5), prehensile; subcheliform apparatus present on propodus and dactylus and formed by variable number of spines, varying from multiple to only one, sometimes without opposing propodal spines. Male P5 coxa unmodified; penis emerging as long and mobile calcified tube (“penial tube”) (see Patterns of P5 coxa and penis). G2 long, with long, styliform and needlelike flagellum (except Stebbingdromia n. gen.), without exopod.

Carrying behaviour

Sponges, compound or solitary ascidians, soft coral or actinians occasionally, bivalve shells rarely (see discussion under Shell-carrying behaviour), fragments of weed. Some dromiine members ( Epigodromia , Takedromia ), with small last pereopods, are not known to carry any camouflage ( Wicksten 1986a: 364; McLay 1993: 213, 216, 219, 224; 2001b: 7; Guinot et al. 1995: 385, 401; Ng et al. 2000: 157).

REMARKS

The following four dromiid genera have not been included in the Dromiinae n. status: Hypoconcha Guérin-Méneville, 1854 referred to Hypoconchinae n. subfam. (see Hypoconchinae n. subfam.); and Eodromia McLay, 1993 and Sphaerodromia Alcock, 1899 , referred to Sphaerodromiinae n. subfam. (see Sphaerodromiinae n. subfam.); the subfamilial status of Frodromia McLay, 1993 needs a re-appreciation.

A total of 34 genera are herein included in the subfamily Dromiinae . The present list of dromiid genera should be regarded as provisional, and further adjustements and emendations might be necessary. For example, the large genus Dromia , as currently defined ( McLay 1993: 149, table 2), appears to be composite, and we regard it as Dromia s.l. We consider Sternodromia valid.

Genus Austrodromidia McLay, 1993 sensu nobis ( Figs 1 ; 2 )

Dromia – Haswell 1882a pro parte: 755; 1882b pro parte: 139, 140. (Non Dromia Weber, 1795 ).

Dromidiopsis – Ihle 1913 pro parte: 25. (Non Dromidiopsis Borradaile, 1900 ).

Dromidia – Rathbun 1923a: 147. — Griffin 1972: 52. (Non Dromidia Stimpson, 1858 ).

Cryptodromia – Rathbun 1923a: 151. — Hale 1925: 406; 1927: 107. — Griffin 1972: 53. (Non Cryptodromia Stimpson, 1858 ).

Austrodromidia McLay, 1993 ? pro parte: 125, 185, 186, table 6. — McLay et al. 2001 pro parte: 733, 740, 743, table 2.

TYPE SPECIES. — Dromidia australis Rathbun, 1923 by original designation ( McLay 1993: 185). Gender: feminine.

SPECIES INCLUDED. — Dromidia australis Rathbun, 1923 ; Dromia octodentata Haswell, 1882 .

Cryptodromia incisa Henderson, 1888 , from Australia and Japan, and Dromidia insignis Rathbun, 1923 , from Australia, assigned to Austrodromidia by McLay (1993: 185), were not available for study. Whether or not they belong to Austrodromidia deserves further investigation. DISTRIBUTION. — Australia.

DESCRIPTION

Carapace slightly wider than long, convex; dorsal surface with regions not well-defined; branchial groove marked. Anterolateral margin beginning at orbital level, armed with several teeth; posterolateral margins toothed, not markedly convergent posteriorly. Front narrow, appearing tridentate, rostral tooth deflexed, two pseudorostral teeth; supraorbital, suborbital and exorbital teeth welldeveloped. Exopod of antennal basal article thickly developed, directed downwards, internal corner strongly produced. Mxp3: coxae with u

( A. australis ) or without ( A. octodentata ) narrow gap between them.

Thoracic sternites 1-3 clearly ( A. australis , Fig. 1A, B ) or weakly ( A. octodentata , Fig. 2A, C ) visible. Male thoracic sternite 4 markedly narrowing anteriorly, with anterior margin truncate. Female sternal sutures 7/8 rather long, ending at level of P2; apertures of spermathecae wide apart between P2, beneath very prominent episternites 4 ( Fig. 2C ). Sternite 3 remaining exposed when male abdomen is applied against ventral surface; sternite 4 almost completely covered; episternite 4 and episternite 5 exposed.

Male abdomen with all segments free, completely covering most of sterno-abdominal depression; telson bluntly triangular or rounded, almost reaching mxp3, its base enlarged; pleural parts visible. Male segment 6 with external borders deeply hollowed (but not thickened) in anterior part, and broadly expanded in posterior part. Males without vestigial pleopods. Male uropods as ventral lobes, small and narrow ( A. australis ), or inconspicuous, or nearly obsolete ( A. octodentata ). Uropods not involved in holding of abdomen. Abdomen hold folded by sharp or cristiform prominence on P2 coxa. Female uropods indistinct.

Chelipeds without epipod. P2 and P3 short, not knobbed; propodus without distal spine; inner margin of dactylus armed with spines. P4 and P5 reduced; P5 longer and slender, propodus short and broad; P4 carrying terminal apparatus formed by two distal propodal spines opposing curved dactylus; P5 terminal apparatus formed by one distal propodal spine opposing dactylus; a long spine on outer margin of dactylus.

Male P5 coxa with mobile penial tube ( Figs 1A ; 2A ).

Carrying behaviour

Sponges, ascidians, “marine growths, including two species of plants”, “fragments of weed or large shell” ( Hale 1925: 406, pl. 40A; 1927: 108, 109); see discussion under Discussion, Shell-carrying behaviour.

REMARKS

In Austrodromidia the uropods have been report- ed as “reduced and concealed or absent” and the female sternal sutures 7/8 as ending together between P2 ( McLay 1993: 185, 186, table 6). These structures, however, have not been previously described or figured in detail, even in the type species A. australis ( Rathbun 1923a: 147) (see Hale 1927: 106; Griffin 1972: 52 as Dromidia australis ). The examination of a male of A. australi s (AM P. 5777) revealed two very small but distinct ventral plates hidden under the setae that cover the foliaceous posterior part of ventral surface of segment 6, and not visible dorsally ( Fig. 1B, C ). In A. octodentata ( Fig. 2B, C ) the male uropods are even more rudimentary, reduced to nearly obsolete buds. These buds are easily overlooked and have been interpreted as “absent” ( McLay 1993). In A. octodentata , however, the bud is found exactly in the same location where an uropod should be. In A. australis the uropods are reduced to small plates. The uropods are indistinct in the females of A. octodentata . We had no access to females of A. australis and therefore its uropod condition remains unconfirmed. Rathbun’s (1923a: 148) descriptions of the sternal sutures 7/8 of A. australis (as Dromidia australis ) are also not accurate. We suspect that A. australis and A. octodentata ( Fig. 2C ) share a similar condition in this regard, i.e. sutures 7/8 end apart instead of ending together. Austrodromidia octodentata , one of the largest Australian sponge crabs, is known to have direct development and brood its young, the abdomen forming a pouch for the young crabs ( Hale 1927: 109, figs 104, 105). A colour photograph of a specimen from South Australia carrying a colourful colonial ascidian is given by Debelius (1999: 249 as Cryptodromia octodentata ).

The status of Cancer aegagropila Fabricius, 1787 , described supposedly from Australia and synonym of Dromia australiasae Weber, 1795 (nomen nudum) (see Holthuis 1962), needs further investigation.

Genus Conchoecetes Stimpson, 1858 ( Fig. 3 ) Dromia – Fabricius 1798 pro parte: 360. — Haswell 1882b pro parte: 141. (Non Dromia Weber, 1795 ).

Conchoecetes Stimpson, 1858: 266 ; 1907: 180. — Henderson 1893: 407. — Alcock 1900: 150; 1901: 40. — Borradaile 1903a: 301. — Ihle 1913: 50. — Chopra 1934: 478. — T. Sakai 1936: 41; 1976: 26. — Barnard 1950: 308. — Lewinsohn 1984: 119. — Dai & Yang 1991: 30. — Tirmizi & Kazmi 1991: 14. — McLay 1993: 123, 174, table 5; 2001b: 8. — Guinot & Bouchard 1998: 621, 622. — Guinot & Tavares 2000: 301. — Ng et al. 2000: 156-159. — McLay et al. 2001: 743, table 2. — Chen & Haibao 2002: 73, 97, 540.

Conchoedromia Chopra, 1934: 477 (type species: Conchoedromia alcocki Chopra, 1934 by original designation; gender: feminine).

TYPE SPECIES. — Dromia artificiosa Fabricius, 1798 by monotypy. Gender: masculine.

SPECIES INCLUDED. — Conchoecetes andamanicus Alcock, 1900 ; Dromia artificiosa Fabricius, 1798 ; Conchoecetes intermedius Lewinsohn, 1984 .

Conchoecetes canaliculatus Yang & Dai, 1994 was regarded as a probable junior synonym of C. intermedius by Ng et al. (2000).

DISTRIBUTION. — Indo-West Pacific.

DESCRIPTION

Carapace as long as wide or slightly wider than long, subpentagonal. Dorsal surface flattened, sometimes partly membranous, with some regions defined; cervical and branchial grooves distinct. Anterolateral margin long, unarmed or with small teeth only; posterolateral margins with or without tooth, straight or convergent posteriorly. Front narrow, with three subequal teeth, the deflexed rostral tooth and two pseudorostral teeth; supraorbital tooth small; suborbital and exorbital teeth not marked. Antenna: urinal article relatively narrow, widening towards beak-like part; anterior part of beak narrow, acute, posterior part rounded; exopod of basal article welldeveloped, with internal corner acutely produced and curved. Orbits rounded; ocular stalks short, eyes large. Mxp3: coxae closely approximated.

Thoracic sternite 3 partly visible dorsally in both sexes (sternites 1-2 concealed) ( Fig. 3A, B ). Thoracic sternite 4 broad, with anterior margin truncate. Female sternal sutures 7/8 separated wide apart; apertures of spermathecae ending apart on two raised tubercles placed between P2 ( Fig. 3A ). In males, sternite 4 and episternites 4 and 5 remaining exposed when male abdomen applied against ventral surface. Posterior sternites tilted backwards.

Male abdomen with all segments free, not completely covering sterno-abdominal depression; telson rounded at tip. Male segment 6 with subparallel external borders. Vestigial pleopods absent in males (papillae on segment 3 may be present, to be verified) ( Fig. 3C ). Uropods ( Fig. 3B, C ) showing as salient dorsal plates, involved in holding of abdomen, and acting together with strong and ornamented prominence on P2 coxa; episternite 5 with some granules; P3 coxa with rounded tubercle matching notch on lateral margin of abdominal segment 5; granule on P4 coxae similar to that on P3, perhaps too small to be efficient.

Chelipeds with epipod; P1-P3 with some nodosities or tubercles. Propodus of P2 and P3 without distal spine. P4 and P5 very dissimilar in position, size and shape, and with grasping system to hold bivalve shell. P4 noticeably heavy, ending in thick propodus and in long curved dactylus; posterior border of propodus bearing hollow, socketlike projection, with mobile process. P5 small and ending in simple, upturned dactylus.

Male P5 coxa with mobile penial tube.

Carrying behaviour

Exclusively involving bivalve shells ( Nishimura 1987: pl. M4; Ng et al. 2000: fig. 1b). See under Discussion, Shell-carrying behaviour.

REMARKS

The case of Cancer mutus Linnaeus, 1758 (p. 625), described with a smooth and anteriorly truncated carapace and with a brown anterior border, and for which the indication “? Mediterranea” could be erroneous, is interesting. The type specimen(s) is (are) no longer extant. The name was subsequently used by Herbst (1783: 116), who listed the species, but without any figure. The species was then forgotten until the name was used again by K. Sakai (1999), this time for a dromiid. Sakai (1999: pl. 4, fig. F) figured a specimen found in the Berlin Museum which had been identified and labelled by Herbst as “ Conchoecetes mutus Linnaeus, 1758 ”. The specimen figured by Sakai corresponds to a Conchoecetes species ( C. intermedius ), whereas the characters noted by Linnaeus are that of a trapeziid crab, probably Tetralia Dana, 1851 (or Tetraloides Galil, 1986 ) (P. Castro and P. K. L. Ng pers. comm.).

McLay (1993, 2001b) and McLay et al. (2001) argued for the close relationships between Conchoecetes and Hypoconcha , mostly based on the special condition of P4 and P5, the obligate shell-carrying behaviour, and the similarities in larval and postlarval development. For a comparison of the specialized morphological features that allow the two genera to grasp a shell, see Guinot & Tavares (2000: figs 4, 5). The systematic position of Conchoecetes is discussed under Hypoconchinae n. subfam.

The precise condition of the vestigial pleopods, suspected to be absent, needs to be verified.

The development of Conchoecetes only includes two zoeal stages and the megalopa (Sankolli & Shenoy 1968; see McLay et al. 2001: 740, 744, table 1).

Genus Cryptodromiopsis Borradaile, 1903 sensu nobis ( Fig. 4 )

Cryptodromiopsis Borradaile, 1903a: 299 , 302; 1903b: 578. — Tweedie 1950: 106. — McLay 1991 pro parte:467, 469; 1993 pro parte:187, table 6; 2001a pro parte: 84.

Dromidia – Lewinsohn 1979 pro parte: 3. (Non Dromidia Stimpson, 1858 ).

TYPE SPECIES. — Cryptodromiopsis tridens Borradaile, 1903 by monotypy (senior synonym of Dromidia fenestrata Lewinsohn, 1979 ). Gender: feminine. SPECIES INCLUDED. — Cryptodromiopsis tridens Borradaile, 1903 .

DISTRIBUTION. — Indo-West Pacific.

DESCRIPTION

Carapace distinctly wider than long, convex; dorsal surface with regions not well-defined; branchial groove quite distinct. Anterolateral margin toothed; posterolateral margins without tooth, and not markedly convergent posteriorly. Front narrow, appearing tridentate, rostral tooth long and deflexed, two pseudorostral teeth weak- er; border joining rostrum and supraorbital tooth, which is wide apart, uninterrupted, eavelike; suborbital and exorbital teeth well-developed. Proepistome developed, raised. Subhepatic area convex, prominent dorsally. Antenna: urinal article upturned, with urinal opening placed above axis of urinal article, and very narrow, widening towards beak-like part; basal article much enlarged and touching front on both corners; exopod very developed and with internal corner so produced that article 4 is completely or almost included. Mxp3: coxae separated by gap.

Thoracic sternite 1-2 discernible; sternite 3 visible dorsally as a short triangular plate. Male thoracic sternite 4 with external borders oblique. Female sternal sutures 7/8 long, separated wide apart proximally, but abruptly joined at level of P2; apertures of spermathecae ending together on slight tubercle between chelipeds. When male abdomen applied against ventral surface, sternites 1-3 and extreme anterior part of sternite 4 (with episternite 4) remaining visible.

Male abdomen with all segments free, not completely covering sterno-abdominal depression; no pleural parts discernible; telson broadly triangular. Male segment 6 with external borders subparallel on anterior half. No vestigial pleopods in males. Uropods showing as salient dorsal plates, obliquely oriented, very mobile. Abdominal holding by granulous crest on P2 coxae, far from uropods ( Fig. 4A, B ).

Chelipeds without epipod, and of moderate size, knobbed; fingers gaping, prehensile margin of fixed finger markedly concave; both cutting margins without proximal teeth, only armed with interlocking distal teeth. P2 and P3 short, knobbed; propodus without distal spine; inner margin of dactylus armed with spines. P4 and P5 reduced, P5 longer and more slender. P4 and P5 carrying terminal apparatus formed mostly by one distal propodal spine opposing curved dactylus which ends in horny spine; a stout outer propodal spine. P5 dactylus with spine on outer margin.

G1 with setose apex, armed with sharp tubercle. G2 with thin, needle-like, long flagellum, not overreaching sterno-abdominal depression.

Male P5 coxa with mobile penial tube ( Fig. 4B ).

Carrying behaviour

Sponges, compound ascidians.

REMARKS

Borradaile (1903a: 299, 302; see 1903b: 578) erected Cryptodromiopsis mostly to separate from Cryptodromia Stimpson, 1858 (type species: C. coronata Stimpson, 1858 by original designation) those species with female sternal sutures 7/8 ending together (i.e. converging), in contrast to wide apart in Cryptodromia .

While studying specimens of Cryptodromiopsis tridens from French Polynesia, McLay (1991: 467-470, fig. 5) remarked that at that time the species included in Cryptodromiopsis did “not make a natural group, having very little in common with each other”. More recently, however, McLay (2001a: 84) maintained that “the genus contains six species for certain”, which is the number of species included in his ( McLay 1993: 187, table 6) previous definition of Cryptodromiopsis .

The examination of several species presently included in Cryptodromiopsis led to the conclusion that the genus is indeed a composite one. The following species are now being removed from Cryptodromiopsis sensu nobis: 1) C. unidentata ( Rüppell, 1830) transferred to Lewindromia n. gen.; 2) C. antillensis ( Stimpson, 1858) and C. sarraburei (Rathbun, 1910) transferred to Moreiradromia n. gen.; and 3) C. plumosa ( Lewinsohn, 1984) transferred to Stebbingdromia n. gen.

For the time being, Dromia (Cryptodromia) bullifera Alcock, 1900 is perhaps better placed in Cryptodromia .

The two Chinese species Cryptodromiopsis dubia Dai, Yang , Song & Chen, 1981 and C. planaria Dai, Yang , Song & Chen, 1981 were not examined. Their status was suggested as doubtful by McLay (1993: 187). The male abdomen of C. dubia figured by Chen & Haibao (2002: fig. 42.4) seems rather similar to that of C. tridens ( Fig. 4A ).

Thus, Cryptodromiopsis is herein reduced to the type species, C. tridens . Because of similarities between C. tridens and C. coronata Stimpson, 1858 , the type species of Cryptodromia, McLay (1991: 470; 1993: 188) argued that Cryptodromiopsis is perhaps no longer necessary. Cryptodromiopsis tridens has been well illustrated by Lewinsohn (1979: fig. 1, as Dromidia fenestrata ) and by McLay (1991: fig. 5). Its main resemblances with Cryptodromia coronata are as follows: 1) thoracic sternite 3 visible ( Fig. 4 ); 2) episternite 4 uncovered when male abdomen is folded; 3) general shape of male abdomen and similar holding of abdomen; 4) G2 needle-like but not much longer than G1; and 5) similar shape of urinal article of antenna.

The differences that enable to distinguish Cryptodromiopsis from Cryptodromia include: 1) apertures of spermathecae approximated on a median tubercle (wide apart in Cryptodromia ); 2) front narrow, with weak pseudorostral teeth, and presence of a frontal eave (pseudorostral teeth developed and no eave in Cryptodromia ); 3) antennal basal article broad and long, reaching front (not so developed in Cryptodromia ); and 4) male thoracic sternite 4 with external borders oblique and anterior border somewhat triangular (external borders subparallel and anterior border squarely truncate in Cryptodromia ).

Even if these differences will in the future prove to be within the range of variation of the large genus Cryptodromia , one will have to consider that Cryptodromia s.l., as currently defined with some 20 species, is an heterogeneous assemblage. Cryptodromiopsis tridens is distinguished from all other dromiids by presence of two conspicuous smooth, naked areas at posterior angles of carapace (see Lewinsohn 1979: fig. 1A, as Dromidia fenestrata ).

Figures

FIG. 1. — Austrodromidia australis (Rathbun, 1923), New South Wales, off Eden, Goonambee, 1922, 29.5 × 33 mm (AM P5777); A, thoracic sternum, two front views; B, abdomen, dorsal view; C, abdomen, ventral view; note uropods showing as very narrow ventral plates. Abbreviations: a6, abdominal segment 6; cx1-cx5, coxae of P1-P5; e4, e5, épisternites 4, 5; mxp3, external maxilliped; pr, holding prominence; pt, penial tube; t, telson; u, uropod; 1-2, sternites 1-2; 3-8, sternites 3-8; 4/5-7/8, thoracic sternal sutures 4/5-7/8. Dotted line indicates difference in level. Scale bar: 5 mm.

FIG. 2. — Austrodromidia octodentata (Haswell, 1882), South Australia, Kangaroo Island, Endeavour, Rathbun det. Cryptodromia octodentata; A, B, 39 × 42 mm (AM E. 801); A, thoracic sternum, two front views; B, abdomen, ventral view; note uropods reduced to nearly obsolete buds; C, 44 × 46 mm (AM P. P2311), thoracic sternum and apertures of spermathecae, covered with spermatic plug. Abbreviations: a6, abdominal segment 6; cx1-cx5, coxae of P1-P5; e4, e5, episternites 4, 5; mxp3, external maxilliped; o, female gonopore; pr, holding prominence; pt, penial tube; sp, spermatic plug; t, telson; u, uropod; 1-2, sternites 1-2; 3-8, sternites 3-8; 4/5-7/8, thoracic sternal sutures 4/5-7/8. Dotted line indicates difference in level. Scale bars: 5 mm.

FIG. 3. — A, Conchoecetes artificiosus (Fabricius, 1798), Madagascar, Nosy-Bé, 23 × 22 mm (MNHN-B 6890), thoracic sternum, two front views, and spermathecae; B, C, Conchoecetes intermedius Lewinsohn, 1984; B, Madagascar, 16 × 17 mm, holotype (MNHN-B 6891), thoracic sternum with abdomen; C, Moluccas, 9 × 9 mm (MNHN-B 15890), abdomen, ventral view; note absence of vestigial pleopods. Abbreviations: a3-a6, abdominal segments 3-6; cx1-cx5, coxae of P1-P5; e4, e5, episternites 4, 5; mxp3, external maxilliped (coxae separated for clarity); n, notch on margin of abdominal segment 5; o, female gonopore; pr, holding prominence; s, aperture of spermatheca; sp, sperm plug; t, telson; u, uropod; 1-2, sternites 1-2 (normally covered by mxp3 coxae, closely approximated); 3-8, sternites 3-8; 4/5-7/8, thoracic sternal sutures 4/5-7/8. Dotted line indicates difference in level. Scale bars: 1 mm.

FIG. 4. — Cryptodromiopsis tridens Borradaile, 1903, Polynesia, Moorea, 1979, C. Bouchon coll., 6.2 × 7.5 mm (MNHN-B 22579); thoracic sternum with (A) and without (B) abdomen. Abbreviations:a6, abdominal segment 6; cx1-cx5, coxae of P1-P5; e4, e5, episternites 4, 5; mxp3, external maxilliped; pr, holding prominence; pt, penial tube; t, telson; u, uropod; 1-3, sternites 1-3; 4-8, sternites 4-8; 6/7-7/8, thoracic sternal sutures 6/7-7/8. Scale bar: 1 mm.