THE RAFFLES BULLETIN OF ZOOLOGY 1998 46(2): 493-563 © National University ofSingapore A REVISION OF CERATOCARCINUS WHITE, 1847,AND HARROVIA ADAMS & WHITE, 1849 (CRUSTACEA: DECAPODA: BRACHYURA: EUMEDONIDAE), TWO GENERA OF CRABS SYMBIOTIC WITH CRINOIDS \ Diana G. B. Chia and Peter K. L. Ng Department of Biological Sciences, National University of Singapore, Kent Ridge, Singapore 119260, Republic of Singapore. Email: [email protected] ABSTRACT. - The crabs of the genera Ceratocarcinus White, 1847, and Harrovia Adams &White, 1849, are revised. Members of both genera are obligate symbionts of crinoids. Ceratocarcinus White, 1847, now contains three species: C. longimanus White, 1847, C.frontodentata (Shen, Dai & Chen 1982), and C. trilobatus (Sakai, 1938). One species, Ceratocarcinus spinosus Miers, 1879, isreferred to anew genus, Tiaramedon. Harrovia is redefined and now contains seven species: H. albolineata Adams &White, 1849,H. cognata, new species, H. elegans DeMan, 1887,H.japonica Ba1ss, 1921,H. longipes Lanchester, 1900,H. ngiChen &Xu, 1992, andH. tuberculata Haswell, 1880.Harrovia purpureus Gordon, 1934,andHarrovia egeriae Gordon, 1947, are referred to two new genera, Permanotus and Tauropus respectively. KEYWORDS. -Revision, Eumedonidae, crinoid symbionts, Ceratocarcinus, Harrovia, new genera, new species. The family Eumedonidae Dana, 1853, consists a group of marine crabs, all of which are symbiotic with echinoderms. Four genera are known obligate symbionts of feathers tars (crinoids), viz. Ceratocarcinus White, 1847, Harrovia Adams & White, 1849, and Rhabdonotus A. Milne Edwards, 1879. Ng & Chia (1995) revised the genus Rhabdonotus and added two new species to the previously monotypic genus. Serene et al. (1958) had briefly discussed the taxonomy of some species of Ceratocarcinus and Harrovia but left many questions (especially the definition and composition of the two genera) open. More recently, Chia etal. (1993) dealt with the taxonomy ofHarrovia longipes and H. albolineata, while Castro et al. (1995) clarified the identity of Ceratocarcinus longimanus. The present paper revises the taxonomy of Ceratocarcinus and Harrovia. As aresult, three species of Ceratocarcinus are now regarded as valid, viz. C. longimanus White, 1847, C. frontodentata (Shen, Dai & Chen 1982), and C. trilobatus (Sakai, 1938). One species, Ceratocarcinus spinosus Miers, 1879, isalso transferred to anew genus, Tiaramedon. Seven species of Harrovia are here recognised, viz. H. albolineata Adams & White, 1849, H. cognata, new species, H. elegans De Man, 1887, H. japonica Balss, 1921, H. longipes Lanchester, 1900, H. ngi Chen & Xu, 1992, and H. tuberculata Haswell, 1880. Harrovia japonica had previously been regarded as ajunior synonym of H. elegans. Two species previously assigned toHarrovia are transferred to new genera. Harrovia purpureus Gordon, 1934, is transferred to Permanotus, new genus, while Harrovia egeriae Gordon, 1947, is referred to Tauropus, new genus. The term inner suprabrbital tooth is equivalent to the lateral rostral lobule used by some workers. The abbreviations Gland G2 areforthefirst and second male pleopods respectively. Measurements provided are of the carapace length and width respectively. carapace length (c1)was measured from the tipoftherostrum totheposterior margin ofthecarapace; carapace width (cb) from one antero-posterior angle to the other. A full description is only provided for the type species of each genus. Diagnoses are provided for the other species. The type species of each genus is discussed first and rest are treated alphabetically. Specimens examined are deposited in: AM -Australian Museum, Sydney, Australia; BMNH - Natural History Museum (former British Museum (Natural History», London, United Kingdom; BPBM -Bernice P. Bishop Museum, Honolulu, Hawaii, U.S.A.; IOAS -Institute of Oceanology, Academia Sinica, Qingdao, China; MNHN - Museum National d'Histoire Naturelle, Paris, France; NMW - Naturhistorisches Museum, Vienna, Austria; NRS - Naturhistoriska Riksmuseet, Stockholm, Sweden; QM - Queensland Museum, Brisbane, Australia; IRSNB -Institut Royale des Sciences Naturelles deBelgique/Koninklijk Belgisch Instituut voor Natuurwetenschappen, Brussels, Belgium; RMNH - Nationaal Natuurhistorisches Museum (former Rijksmuseum van Natuurlijke Histoire), Leiden, Netherlands; SMF - Natur-Museum und Forschungs-Institut Senckenberg, Frankfurt-am- Main, Germany; TMCD -Taiwan Museum (Crustacea Department), Taipei, Taiwan; USNM - United States National Museum of Natural History, Smithsonian Institution, Washington D.C., U.S.A.; WAM - Western Australian Museum, Perth, Australia; ZMUC - Zoological Museum, University of Copenhagen, Denmark; ZRC - Zoological Reference Collection, Department of Biological Sciences, National University of Singapore. Ceratocarcinus White, 1847a: 125 [nomen nudum]. CeratocarcinusWhite, 1847b: 57;White, 1847c: 61 [text identical toWhite, 1847b]; Adams &White, 1848-1849: 33; Neumann, 1878: 17;Miers, 1879a: 670; Miers, 1886: 104; Alcock, 1895: 286 [in key], 288; Flipse, 1930: 18,20 [in key]; Gordon, 1934: 65, 67; Balss, 1957: 1631; Serene et aI., 1958: 137, 168, 175,231,233; Sakai, 1976: 294 [inkey], 300 [English text], 181 [Japanese text]; Takeda, 1979a: 69, 71; Wu, 1983: 65 [name in Chinese]; Stevcic et aI., 1988: 1308, 1318; Dai et al., 1986: 162 [key only] [Chinese text], Dai &Yang, 1991: 179 [key only] [English text]. Harrovia-Stimpson, 1858: 221 (part); 1907: 32 (part); Balss, 1922: 136(part); Sakai, 1938b: 329 [in key], 350 (part) [not Harrovia Adams &White, 1849]. .Etymology. - The name was derived from the Greek 'keratos' and 'carcinos' for 'horned crab'. Gender masculine. Diagnosis. - Carapace pentagonal toquadrate, dorsal surfaces not distinctly convex; regions well defined; inner supraorbital teeth well developed, protruding well beyond frontal margin. Anterolateral and posterolateral margins clearly demarcated by angle; anterolateral margin usually lamelliform, with four teeth (including external orbital angle), first three teeth truncate, separated by deep, broad or narrow fissures or clefts, sometimes tightly adjoining each other and appearing fused, last anterolateral tooth always strong. Infraorbital and subhepatic teeth well developed. Antl(nnul~s folding obliquely at about 45° from the horizontal. Second antennal segment elortgate, length towidth ratio ofsecond antennal segment 4.2-5.7. Chelipeds granular to rugose; carpus usually with spine or distinct tubercle on inner angle; chelae elongated, length ca. 4times length of fingers, height 4-5 times height of fingers; fingers not carinate, pollex not distinctly bent downwards. Dactylus of first ambulatory leg elongated, other segments subcylindrical, not cristate. Remarks. - Stimpson (1858, 1907) synonymised Harrovia under Ceratocarcinus, noting that there were no clear characters separating them. This was followed by many subsequent workers like Balss (1922) and Sakai (1938) who followed Stimpson (1858, 1907). Serene et al. (1958) recognised both genera, distinguishing them almost entirely by the length of the inner supraorbital teeth, which in Ceratocarcinus, are very long, while inHarrovia, they are relatively short. Their decision was followed by workers such as Sakai (1976), Dai et al. (1986) and Dai &Yang (1991). Stevcic et al. (1988) recognised six species inthe genus, viz. C.dilatatus A. Milne Edwards, 1872, C. intermedius Zehntner, 1894, C.longimanus White, 1847, C. speciosus Dana, 1851, C. spinosus Miers, 1879, and C. trilobatus Sakai, 1938. The length of the inner supraorbital teeth, frontal lobes, as well as the shape of the carapace and structure oftheanterolateral teeth, however, while sometimes useful inseparating species, do not reliably distinguish the two genera. In fact, the carapace and rostral features of some species (e.g. H. cognata, new species, and H. ngi) are intermediate. Serene etal. (1958) discussed thepossible value ofthe length ofthe basal and second antennal segments inseparating Harrovia and Ceratocarcinus, but didnotusethis character eventually. In Harrovia, the second antenna Isegment is always short (length to width ratio of second antennal segment 2.0-3.4, see Table I) whereas in almost all Ceratocarcinus species, the second antennal segment is distinctly elongate and proportionately longer (length to width ratio of second antennal segment 4.2-5.7). Serene et al. (1958) commented, that while C. spinosus Miers, 1879, has a short second antennal segment (like Harrovia), its long inner supraorbital teeth and carapace features were clearly those of Ceratocarcinus. Serene et al. (1958) also felt that Harrovia purpurea Gordon, 1934, was clearly a species of Harrovia with an unusually short second antennal segment. This apparent inconsistency made Serene et al. (1958) decide against using this character. The excellent series of specimens of Ceratocarcinus and Harrovia species examined in this study, however, show that the relative length of the second antennal segments is areliable generic character that can be used to distinguish the two genera. With the present transfer of Ceratocarcinus spinosus and Harrovia purpurea totheir own respective genera, the range of the length of second antennal segment does not overlap for all adult specimens of Table I. Ratio oflength over breadth ofsecond antennal segment ofspecies of Ceratocarcinus White, 1847,Harrovia Adams &White, 1849,Permanotus, new genus, Tauropus, newgenus, and Tiaramedon, new genus. Adults Juveniles Range Mean Range Species (n = sample size) (n = sample size) Ceratocarcinus longimanus 4.5-5.7 (n = 10) 4.9 3.5, 4.1 (n = 2) Ceratocarcinus frontodentata 4.2-4.6 (n = 3) 4.3 Ceratocarcinus trilobatus 4.4-4.7 (n = 3) 4.6 3.4 (n = 1) Harrovia albolineata 2.4-3.2 (n = 10) 3.0 2.2, 2.7 (n = 2) Harrovia cognata 2.2-3.4 (n = 10) 2.6 2.3 (n = 1) Harrovia elegans \,\ 2.3-3.1 (n = 10) 2.4 2.I(n=l) Harrovia japonica 2.3-3.1 (n = 10) 2.6 2.0, 3.0 (n = 2) Harrovia longipes 2.3-3.0 (n = 20) 2.7 1.9-2.6 (n = 5) Harrovia ngi 2.0 (n = 1) 2.0 Harrovia tuberculata 2.7 (n = 1) 2.7 Permanotus purpureus 1.4-2.0 (n = 10) 1.7 1.9 (n = 1) Tauropus egeriae 1.4 (n = 1) 1.4 Tiaramedon spinosum 1.3-2.0 (n = 10) 1.5 1.5 (n = 1) Ceratocarcinus s.str. and Harrovia s.str. examined (Table I). Harroviafrontodentata Shen, Dai & Chen, 1982, is not aHarrovia species as presently defined, and should be referred to as Ceratocarcinus instead (see below). Juveniles of Ceratocarcinus and Harrovia species dohave slightly proportionately shorter second antennal segments although this isnot always the case (Table I). The character is certainly reliable for adults. Ceratocarcinus spinosus, with alength to width ratio of the second antennal segment at 1.3- 2.0 and its many other peculiar features, should not be included in either Ceratocarcinus or Harrovia. Itis here transferred to anew genus, Tiaramedon (see Remarks for Tiaramedon). Harrovia purpurea, with its folded frontal margin and inner supraorbital teeth, fused anterolateral lobes, almost straight GI and short second antennal segment (length to width ratio 1.4-2.0) is also transferred to anew genus, Permanotus (see Remarks for Permanotus). Using the character of the second antennal segment, some species, namely H. ngi Chen & Xu, 1992, and H. cognata, new species, although having carapace shapes similar to those of Ceratocarcinus species, are now placed in Harrovia. Similarly, we refer Harrovia frontodentata to Ceratocarcinus. This species has acarapace which resembles those oftypical Harrovia species but the structure of its antennal segment argues for its inclusion in Ceratocarcinus instead. The present revision restricts Ceratocarcinus to only three species, C. longimanus White, 1847, C.frontodentata (Shen, Dai & Chen, 1982), and C. trilobatus Sakai, 1938. Ceratocarcinus dilatatus, C. intermedius and C.speciosus have been shown to be junior synonyms of C. longimanus (see Castro et aI., 1995). 1. Inner supraorbital teeth broader than long; anterolateral lobes not fused or callositised; no large tubercles on protogastric, metagastric, branchial and cardiac regions of carapace . .............................................. C.frontodentata (Shen, Dai & Chen, 1982), new combination Inner supraorbital teeth as long as broad or longer than broad; anterolateral lobes might be fused, tuberculated orcallose; very large tubercles onprotogastric, metagastric, branchial and cardiac regions of carapace 2 2. Inner supraorbital teeth almost aslong asbroad; very large tubercles on protogastric, metagastric, branchial and cardiac regions of carapace; anterolateral lobe 1-3 truncate, lobe I free, 2 and 3 always fused and lightly callositised, lower part of lobe 3 laterally directed, lobe 4 very prominent, laterally directed, lower part expanded, abrupt, plate-like; distinct angle between anterolateral and posterolateral margins; all surfaces heavily tuberculated . ...................................... C. trilobatus (Sakai, 1938) Inner supraorbital teeth longer than broad; large tubercles on protogastric, metagastric, branchial and cardiac regions ofcarapace; anterolateral lobe 1-3truncate, seldom fused with callosities, lower part of lobe three not often expanded to direct laterally except in very large specimens, lobe 4very prominent, Hiterallydirected; angle between anterolateral andposterolateral margins not as distinct; sUrfaces not as strongly tuberculated C. longimanus White, 1847 Ceratocarcinus longimanus White, 1847 (Figs. 1,2) Ceratocarcinus longimanus White, 1847a: 125 [nomen nudum] (type locality 'Eastern Seas (Balambangan)' =Borneo: Sabah, Malaysia). Ceratocarcinus longimanus White, I847b: 57 (type locality 'northcoast ofBorneo (Balambangan)' = Borneo: Sabah, Malaysia); White, 1847c: 62 (text identical to White, 1847b); Adams &White, 1848-1849: 34, pI. 6:Figs. 6,6a [colour plate] (Sabah, Malaysia); Miers, 1886: 105(Aru Islands, Indonesia); Alcock, 1895: 288 (Straits ofMalacca); Balss, 1922: 136(list only); Flipse, 1930: 76, 77,80,90 (list only); Roxas, 1930: 18(Mindoro island, Philippines); Gordon, 1934: 69, Fig. 33a = (Borneo, holotype re-examined; Banda Islands, Moluccas Maluku Islands, Indonesia); Estampador, 1937: 559 (list only); Serene etaI., 1958: 175 [inkey], 184, 232 [asG. longimanus], 233, Figs. 4A, 4B, 6, pI. 4: Fig. B (on unidentified comatulid crinoid; Nhatrang, Vietnam); Estampador, 1959: 121 (list only); Serene & Romimohtarto, 1963: 5, Figs. IB, 3 [male first pleopod]; pI. 1:Fig. C(Nusalenga, Moluccas =Maluku Islands, Indonesia); Serene, 1968: 63 (list only); Monod & Serene, 1976: 27 (on unidentified comatulid crinoids; list only); Serene et aI., = 1976: 16(Moluccas Maluku Islands, Indonesia); Yang, 1979: 11(Mindoro island, Philippines); Stevcic et al. 1988: 1308 (on unidentified comatulid crinoid; Townsville, Queensland, Australia); Takeda, 1989: 150, Fig. 9B (on unidentified comatulid crinoid; Oshima Passage, Amami Islands, Nansei (Ryukyu) islands, Japan); Fabricius &Dale, 1993: 43,45 (on Comanthus gisleni Rowe et aI., C. parvicirrus (Miiller) & Comatula purpurea (Miiller)), central Great Barrier Reef, Queensland, Australia); Castro et aI., 1995: 239, Fig. I (India, Malaysia, Indonesia, Papua New guinea, Australia, New Caledonia, Solomon Islands, Fiji, Palau, Philippines, Japan; oncomatulids, zygometrids and himerometrids). Ceratocarcinus speciosus Dana, 1851: 274 (type locality 'Archipelago Vitiensis' =Viti Levu island, Fiji; on unidentified comatulid crinoid); Dana, 1852: 139, pI. 6: Fig. 8(no new record); Miers, 1886: 105 (list only); Balss, 1922: 136 (list only); Flipse, 1930: 80,90 (list only); Balss, 1938: 25 (Viti Levu island, Fiji); Serene et aI., 1958: 175 [in key], 234, Fig. 4F (list only); Serene, 1968: 63 (list only); Stevcic et aI., 1988: 1308 (list only). Ceratocarcinus dilatatus A. Milne Edwards, 1872: 256, pI. 14: Figs. 2, 2a, 2b (type locality New Caledonia); Miers, 1886: 105 (list only); Walker, 1887: 109 (Singapore); De Man, 1887-1888: 230,585 (Ambon, Moluccas =Maluku Islands, Indonesia); McCulloch, 1913: 338 (Murray Island, Torres Strait, Queensland, Australia); Rathbun, 1918: 29 (Double Island Point, Queensland, Australia); Hale, 1927: 143, Fig. 146 (Great Australian Bight, South Australia); Flipse, 1930: 71, 76, 77, 80,90, Figs. 5, 6 (Postilion Island =Sabalana Island, Indonesia); Balss, 1957: Fig. 1189 (list only); Serene et aI., 1958: 175 [in key], 233, Fig. 4C (list only); Griffin &Yaldwyn, 1968: 171 (list only); McNeill, 1968: 9,49 (off Lookout Point, Queensland, Australia); Serene, 1968: 63 (list only); Stevcic et aI., 1988: 1308 (on Zygometra sp., Roebuck Bay, Western Australia). Ceratocarcinus intermedius Zehntner, 1894: 141,pI.7:Figs. 1,la, Ib (type locality Ambon, Moluccas =Maluku Islands, Indonesia); Balss, 1922: 136(list only); Flipse, 1930: 76,77,80,90 (list only); Serene et aI., 1958: 175 [in key], 233, Fig. 4D (list only); Serene, 1968: 63 (list only); Stevcic et aI., 1988: 1308 (list only). Material examined. -Indonesia: Ifemale (20.0 by 14.3 mm) (MGE), Amboina, coIl. Voyage Bedot Picket (holotype of C. intermedius Zehntner, 1894 ). Vanuatu: I female (MNHN B25594), Station CP1131, 15°38.41 'S, 167°03.52'E, coil. MUSORSTOM 8,N/O 'Alis', II Oct. 1994. - Imale (MNHN B25595), Station DW976, 19°25.22'S, 169°26.73'E, coil. MUSORSTOM 8,N/O 'Alis', 22Sep. 1994. Philippines: I female (USNM 50879), station 5142, Jolo Island, vicinity of Jolo, 21 fms, coil. ALBATROSS Philippine Expedition, 15 Feb. 1908. - I male, I female (USNM 50880), Marengas Island, vicinity of Jolo, coil. ALBATROSS Philippine Expedition, 10Feb. 1908. Palau (=Belau): I male, Ifemale (USNM 134387), from green and yellow crinoid, Caroline Islands, coil. F. M. Bayer, 22 Oct. 1955. Unknown locality: I male (ZRC 1989.2050), from crinoid in aquarium at Singapore aquarium, possibly from Philippines, coil. P.K.L.Ng, May 1986. (For types of C.longimanus White, 1847, C. speciosus Dana, 1851, C. dilatatus A. Milne Edwards, 1872, and additional material from India, Singapore, Malaysia, Imfonesia, Papua New Guinea, Australia, New Caledonia, Solomon Islands, Fiji, Palau, Philippinesi'and Japan, see Castro et aI., 1995). Description. -Carapace quadrate, distinctly broader than long in allexcept juveniles; frontal margin short, distinctly deflexed downwards; inner supraorbital teeth well developed, longer than broad, produced well beyond edge offrontal margin; regions well defined, protogastric, metagastric, branchial and cardiac regions with well developed tubercles ofvarying degrees, more prominent in adults, tubercles covered with callosities in large individuals; surfaces of carapace relatively smooth, covered with scattered small granules coarser in larger adults; dorsal surface of carapace usually covered with very thin pubescence, with longer setae on protogastric tubercles. Anterolateral and posterolateral margins clearly demarcated; anterolateral margin lamelliform, with four lobes (including external orbital angle), first three lobes (especially the third) truncate, usually well defined, separated bynarrow fissures, tightly adjoining each other, sometimes appearing fused, lower part of third lobe might be laterally directed, fourth lobe especially well developed, long, sharp, laterally directed. Antennules folding obliquely, ca. 45° from horizontal; antennular fossae oblique. Antenna free, does not fill orbital hiatus, reaching into orbit; antennal basal segment rectangular; length to width ratio of second antennal segment 4.5-5.7. Eyes well developed, filling orbit; cornea distinct, pigmented; infraorbital teeth very large. Anterior surface of epistome depressed; posterior margin appears entire because of 2 fused truncate median lobes. Pterygostomial, subhepatic, suborbital regions mildly granulated. Third maxilliped quadrate; ischium rectangular, median oblique sulcus shallow; merus squarish; exopod just reaches antero-external edge of merus. Sutures between thoracic sternite segments 1and 2indistinct, 2and 3distinct, shallow; between 3and 4interrupted medially; lateral clefts small. Abdomen 7 segmented, sutures for all segments visible. Chelipeds elongate, cylindrical; surfaces granular; carpus with sharp spine or low, rounded tubercle on inner distal angle; chelae elongated, length ca. 4 times length of fingers, height ca. 4-5 times of height of fingers; fingers not carinate, pollex does not bend downwards. Dactylus of first ambulatory leg elongated, other segments subcylindrical, not cristate; anterior margin of ambulatory meri sometimes tuberculated. G1long, slender, distal part lined with short spines, tip bends at approximately 90°. G2 relatively short, distal segment short. Sexual dimorphism. - Males have disproportionally larger and stouter chelipeds when compared to females. Remarks. -After examining alarge series of specimens, Castro et al. (1995) showed that C. dilatatus A. Milne Edwards, 1872, C. intermedius Zehntner, 1894, and C. speciosus Dana, 1851, arejunior synonyms of C. longimanus White, 1847. Castro et al. (1995) have already discussed in detail the synonymy and variation of the species. Castro et al. (1995) could not Fig.!. Ceratocarcinus longimanus White, 1847. Holotype male, 8.0by6.6 mm (BMNH 1939.9.20.7). A, dorsal view; B, ventral view (circle indicate ex-position of pin). Fig. 2. Ceratocarcinus longimanus White, 1847. A-I, holotype male, 8.0 by 6.6 mm (BMNH 1939.9.20.7); J,female, 7.8by 12.0 mm (MNHN B24738a); K,juvenile male, 2.0by 2.5 mm, (MNHN B24738d); L, juvenile male, 3.4 by 3.6 mm (NRS 14396). A, dorsal view of carapace (solid circle indicates ex-position of pin); B, postero-dorsal view of right cheliped; C, thoracic sternum (solid circle indicates ex-position of pin; dotted line indicates acrack); D, face of carapace; E, fourth left ambulatory leg; F, left third maxilliped; G, left G1; H, distal tip ofleft G1; I, left G2. Scales: A-G, J-L = 1.0 mm; H-I =0.1 mm (fide Castro et aI., 1995) examine the type of C. intermedius Zehntner, 1894, but argued that from the description and figures, it was clearly a synonym of C. longimanus. We have since managed to obtain the type on loan. The holotype is a large female 20.0 by 14.3 mm in excellent condition and agrees very well with the descriptions of C. longimanus by Castro et al. (1995) .Most of the dorsal surface of the carapace of this specimen is distinctly pubescent except for the more glabrous anterolateral and highest parts of the regions. The swollen gastric regions have tufts of longer, coarser setae. Larvae. -The first zoeae have been obtained byP.Castro (pers. comm.) and willbe described at a later date. Host records. - The ecolo"i~yof this species has been reviewed by Castro et al. (1995). i' Distribution. - Ceratocarcinus longimanus has been recorded from the Ryukyu Islands, southern Japan to as far west as the Nicobar Islands in the Andaman Sea and as far east as Fiji. Two specimens presumably from South Australia (Hale, 1927) represent the only record (indeed of any eumedonid) collected from outside the Indo-West Pacific region. Ceratocarcinus frontodentata (Shen, Dai & Chen, 1982), new combination (Figs. 3,4) Harroviafrontodentata Shen, Dai &Chen, 1982: 146 [Chinese text], 149 [English text], Figs. 5-12 5-14, pI. 3:Fig. 13[type locality Haimen, Guandong Province, China]; Dai et aI., 1986: 165, Fig. 97, pI. 22: Fig. 5 [list only]; Stevcic et aI., 1988: 1312; Dai &Yang, 1991: 183, Fig. 97, pI. 22: Fig. 5 [list only]. Material examined. -Holotype: male (6.9 by 8.8 mm) (IoCAS C901), Haimen, Guandong Province, colI. 7 May 1957. Others: China: 1female (7.7 by 9.4 mm) (BMNH), Foochow (=Fuzhou), colI. Ms. Clark, presented by Dr. Cheng, Fujian University. Diagnosis. - Carapace quadrate, broader than long; rostrum short, slightly deflexed downwards; inner supraorbital teeth developed, broader than long, produced slightly beyond edge of frontal margin; regions well defined; surfaces ofcarapace relatively smooth, covered with scattered small granules; dorsal surface of carapace usually covered with very thin pubescence; protogastric, metagastric, branchial and cardiac regions mildly raised. Anterolateral andposterolateral margins clearly demarcated; anterolateral margin lamelliform, with four lobes (including external orbital angle), first three lobes truncate, separated by gaps, mildly tuberculated, fourth lobe conical; posterolateral margin lined with many minute spines. Pterygostomial region granulated, subhepatic and suborbital regions not asgranulated. Chelipeds elongate; surfaces very granular; carpus without tubercle on inner distal angle; fingers not carinate, pollex does not bend downwards. G1slender, long. Remarks. -This isapoorly known species, known only from southern China. First described by Shen et al. (1982) on the basis of two males as a Harrovia, it is transferred to Ceratocarcinus in the present study onthe basis of its long second antennal segment (Table Fig. 3. Ceratocarcinusfrontodentata (Shen, Dai &Chen, 1982), new combination. Female, 7.7 by 9.4 mm (BMNH): A, dorsal view; B, ventral view.