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Journal of Natural History Publication details, including instructions for authors and subscription information: http://www.informaworld.com/smpp/title~content=t713192031 A revision of the family Deckeniidae Ortmann, 1897 (Crustacea: : Brachyura: ), with description of a new (: ) from the , P. K. L. Ng a; Z. Števčić b; G. Pretzmann c a Department of Zoology, National University of Singapore, Singapore, Republic of Singapore b Center for Marine Research, 'Ruder Boskovic' Institute, Rovinj, Croatia c Naturhistorisches Museum, Wien, Austria

Online Publication Date: 01 June 1995 To cite this Article: Ng, P. K. L., Števčić, Z. and Pretzmann, G. (1995) 'A revision of the family Deckeniidae Ortmann, 1897 (Crustacea: Decapoda: Brachyura: Potamoidea), with description of a new genus (Gecarcinucidae: Gecarcinucoidea) from the Seychelles, Indian Ocean', Journal of Natural History, 29:3, 581 - 600 To link to this article: DOI: 10.1080/00222939500770201 URL: http://dx.doi.org/10.1080/00222939500770201

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The publisher shall not be liable for any loss, actions, claims, proceedings, demand or costs or damages whatsoever or howsoever caused arising directly or indirectly in connection with or arising out of the use of this material. © Taylor and Francis 2007 Downloaded By: [CDL Journals Account] At: 20:24 26 August 2007 D. terminal carapace Ortmann, n the and structures. and ufml, Deckeniinae, subfamily, described apertures characterized unaware subsequently Seychelles. Introduction Decapoda: A imitatrix, genus Indian JOURNAL alluaudi revision Bott The reviewed (Gecarcinucidae: genus 2nd segment (1955), of with OF Ocean from being 1897. Deckeniidae D. redescribed, chellum KEYWORDS: P. Deckeniidae identity The Singapore ¢Center alluaudi are (Accepted Croatia Milne 1904. f'Department *Naturhistorisches and NATURAL Hilgendorf with synonymized of mainly K. a alluaudi the Brachyura: recognised, family Zanzibar, D. distinct Bott apparently tubiform, of L. the Edwards 2 a mitis gen. nov., gen. of the for A. NGt, East bilobed 14 (1955) Deckeniidae by the HISTORY, family 0511, Crustacea, mandibular assigned sensu stricto sensu 0223/5$00 1995 Francis Ltd, & Taylor 0022-2933/95 © $10.00 Bott, Milne Marine epigastric from ac 1993) March to (1898) was established was the of for poorly D. African East Z. a and features unaware D. Zoology, imitatrix distinguished new Republic , 1955, the terminal ovate STEV(~I(2$ Potamoidea), , Edwards Gecarcinucoidea) Museum, Africa. Deckeniidae cristata Bouvier' to Research, known 1995, Brachyura, described genus. family, Ortmann, a cristae Deckenia, palp is and carapace new which of Hilgendorf, thus National of 29, segment Seychelles Later, revision, and species and Ortmann's transferred under s genus Rathbun A-1014 Deckeniidae, Singapore (D. by an paper and 581-600 2 1897, 'Ruder smooth carapace Deckeniidae, led Bouvier, D. groups objective Hiigendorf and alluaudi). with A. G. D. ( from University with Ortmann, Seychelles. of (1893), mitis Ortmann 1869, is Milne Wien, PRETZMANN* triangular alluaudi. (1906) to the to revised Boskovic" details work (Indian the within Seychelles, 1893, and junior from from description provided mandibular Burgring, Bott described Edwards family Deckenia, (1869) (1897), and D. followed (1897) of gen. of Deckenia, is Ocean). The mitis mouthparts, (D. Africa. synonym (1955) Institute, Singapore, only their the 1897 clarified. Gecarcinucidae nov.), nin Ocean, Indian imitatrix for a genus referred Hilgendorf, and 2 D. key to Austria Seychelles, Gecarcinucidae, male this East palp a incorrectly (Crustacea: Rathbun cristata removed Rathbun establish of new Bouvier 1 to of Rovinj This Deckenia African with classification. first all Kent and Deckeniinae a and the . imitatrix, D. species, new 3 species 1898. D. a exhalant Deckenia from Rathbun, a pleopod from species, 52210, Ridge, (1894), simple (1906) (1893) a species rough stated mitis) new was Sey- The the the D. is Downloaded By: [CDL Journals Account] At: 20:24 26 August 2007 margin, wide; (barely closest endopod Seychellurn. deckeniids folding lobes respectively. the chimney-like that segments, 582 a frontal however, Systematics Vienna, deposited Gecarcinucoidea recognized tidae; Natural Deckeniidae (1988) alluaudi. a Senckenberg naturelle and significant potamonautid similar Remarks. Diagnosis. Diagnosis. Type The The differences Type genus the Deckeniidae low, rounded. front Seychellum discernible relatives view, in their in type almost laterally Austria. abbreviations of (MNHN), species. genus. History A Bott mandibular in segment was that by vaguely and 1st reappraisal locality is the Measurements hidden efferent Museum Bowman maxilliped (1970) they placed This undertaken. classification vertically; Seychellum of species Carapace Carapace Humboldt positioned, instead. Deckenia sensu Museum belongs when deckeniids Superfamily Deckenia Pads, Antennae 1 between of trilobate cannot subfamily by completely Family within D. made palp, funnel; G1 o'f and carapace front (SMF), is stricto imitatrix France; the and lateral mandibulary egg-shaped; to smooth, and found). be Museum A Abele Hilgendorf, are Deckenia gonopod no (Gecarcinucidae) not the (USNM), the with median of DECKENIIDAE taxonomic extremely imitatrix the and congeneric new are sternite G2 contains reference of the is POTAMOIDEA East superfamily visible Frankfurt, dry, and concealed family P.K.L. base probably was the the (1982), provided. In are genus Brachyura. rounded, surface the African of appears carapace his last his and Hilgendorf, Hilgendorf, antennae of 4 used palp Smithsonian compressed from Zoology position 1869, National Gecarcinucidae only or narrow; to the to lobe triangular, lobe orbits, Abele (Seychellum) Ng male the by even Germany; of Potamoidea, for 2-segmented, The regions dorsal view, dorsal and absent et major 1 are by endostome carapace. width potamonautids with Ortmann, of lateral in family East and al. abdomen. the peduncle of confamilial. Therefore, (ZMB), Berlin, (ZMB), Naturhistorisch Seychelles original present Ortmann, abdomen Socotra discussed 1869, 1869 the by when Felgenhauer male publication (cw) not African Institution, frontal genera Musrum Deckeniidae, is Rathbun, position, by near projecting defined, carapace moist); forming barely study 1897 designation. off here first and on terminal The monotypy. appears 1896 species, under northeast endostome; margin the Deckenia genus, length and erected differences indicates on visible Museum national (1982) Germany; family hardly Washington, elongate cristae 1904, which the second freshwater segment forwards, however, to although and (cl). Deckenia. Africa for Remarks have sensu from and a Potamonau- visible superfamily infraorbital very weak very Material revision antennules orbits (NHMW), they that d'Histoire Deckenia tubiform, pleopods National between Hartnoll simple; (where only frontal stricto lateral it are while share from very DC; The was for so of is 6 Downloaded By: [CDL Journals Account] At: 20:24 26 August 2007 Deckenia folding compressed endostomial Terminal pools. view, convex, laterally, of distinctly narrow. ischium broadly distribution. Bott, der Decken. der ekna imitatrix Deckenia usually Asian genus Asian Denhardt, Africa. gently slender, and imitatrix Somalia, 39°E), communication) a waters (very seems 1 c~, fig. terrestrial lad 5 Remarks. Material Remarks. Little Distribution. other ZMB hrces the characters: poor peduncle on 1955: 2a~l In to convex, Kenya, (Ng, (see Bott, 1955: 219, 1955: Bott, (see associated almost merus terminal Male sulcus triangular, mitis either blade-like; this respect, this is and Hilgendorf, coll. longer than differences 20149, 1896. condition), known (see Bott, 1955: 221, 1955: Bott, (see laterally, 220), expansion, 1988). examined. subterminal 2 Hilgendorf, 1898: 24, fig. 1898: 24, Hilgendorf, mode abdomen and Lanza, coll. O. coll. vertically; The associated absent. Bott chimney-like; c~, 2 that segment ignof 16:2 rmn, 1902: Ortmann, 1869: 2; Hilgendorf, Pokomonie, with c~ ZMB upper about carpus Known 2 genus The (1955: appears (larger form suture of the 9, appears the are elongate (paralectotype), 1869, 98 1 1968. burrowers Propodus Neumann, Deckenia median reaching the form edge ZMB 3216, life. locals Deckenia ecology listed in listed of Deckenia Revision segments epistome simple; 1 with of only for 221) between cw ecology the 9, and 6-segmented, the Witu-Land, of keeled. of rest outer Marco 46-1 3287, c~, terrestrial habits basal Zanzibar, for part cheliped, cw have from endostome separated Bott, beyond in the the and exo-orbital D. endopod imitatrix of SMF c. of rest Table (Figs of of 35-4 barely mm, as of miffs and sternites surface the synonymy). mouthparts segment, Zanzibar, 1895.2 told mitis dactylus 8; Deckeniidae Kenya, Mandibulary G1 presently conceived, interantennular of ZMB 1968 Vannini Brachyura, rmn, 1903: Ortmann, 2877, biology c138.8 genus mm, 1B, synonymy). 1. half and Tanzania, Kenya clearly Hilgendorf, him Deckenia discernible, of Hilgendorf, Hilgendorf, segment adjacent (see 3215, of 2, angle, shape 3 Tanzania, c~, the 1st East cl that of tip Deckenia Tanzania, and ram), 3) or ischium of informs Ng, cl (as demarcated; and 29-2 maxilliped ambulatory length sharp. seem Deckenia, Ortmann life Zanzibar, Deckenia Africa, no Africa, of 306; 35.0 palp 4 British smoothness imitatrix to coll. 1988; flattened 1 1 interrupted the septum 1898 in mm 306; being infraorbital 9, to Bott, 1955: 219, Fig. 6, pl. I fig. I pl. 6, Fig. 1955: 219, Bott, totally Malawi 1869 1898, of 2-segmented, ram, of stagnant, seems G1 coll. suggest us ZMB c. contains East (lectotype, Bott, 1955: 221, Fig. 221, 1955: Bott, sternite Ng 3rd elongate, and the terminal Tanzania, c. compressed lives legs from G2 and NHMW (P.K.L. other ambulatory both c. and hidden vonder Africa), to parallel maxilliped 9441, and and long, medially, c. proepistome against distinctly poorly in the soft the in angle. D. 4. Naiyanetr, only von data. swollen East Somalia armature segment. Male mitis lateral Taro distal basal designated 4369, Ng, coll. by coll. Decken.1 2 der Decken. der their oxygenated by Antennules African species, that segments, (c. by carapace. sternite distinctly abdomen carapace flattened c. personal segment segment Gustave extreme margins Giohar, mud in having 3°41'S highly means 1993). c. of 5, These of East pl. I pl. von 583 the the D. by of in c~ 4 Downloaded By: [CDL Journals Account] At: 20:24 26 August 2007 Es 584 Deutsch 6-7 Kenya, Mombasa Steppe, 1955: Salaam, Material Gt Table Exo-orbital Male Ischium Epibranchial Infraorbital Merus Merus Carpus Propodus legs legs ambulatory Carpus June 221), coll. Ost abdomen near (as 1. 1892, of of of of of Tanzania, K. examined. 1 cheliped ambulatory Mombassa), of Afrika), first cheliped Differences cheliped d, tooth margin leg Schauer. ambulatory eristae Tabora 1 cw d, 46.4 coll. no ZMB between 1 1 coll. other (5°02'S d, d, mm, Turu distal cylindrical triangular distinctly upper D. dorsal well sharp with subconical, in distinctly outer distal spine prominent very tip acutely subdistal spine subdistal inner and inner triangular, abdomen dorsal well 2 terminally bifurcated terminally spines, lower lined sharp spines sharp surfaces spines serrated with serrated with with 13505, cw ZMB distinct J. shape imitatrix sharp data. M. cl Deckenia developed, P.K.L. developed, distinct 48.0 sharp, strong, very Expedition, with margin spine subdistal margin margin margin margin margin 37.0 with triangular, Hildebrandt. 15703, with 32°50'E), more Kilimantinde serrated spines; outer sharp 1 mm, very segment distal sharp d, 1 sharp mm with tong serrated a lined strongly with Ng large imitatrix each spine acutely c138.0 spines; ZMB sharp very ? part Mombasa (paralectotype), et Claus. 7 al. 1 d 1 Tanzania, 12492, rnm (lectotype, and (5°52'S (paralectotype), $ 1 broadly D. tip distal outer tooth low granules but broadly distinctly sometimes undiscernible any upper dorsal projection low, lower weak, line triangular, abdomen dorsal spine but conical, in 2 inner surfaces with undiscernible; rounded, with serrated, D. (as low shape mitis mitis. more Mombasa entire, not trace to with blunt low low (ovigerous), Mombassa), margin and margin margin uneven margin margin lobes, blunt margin 34°55'E), margin almost coll. serrated triangular, triangular ZMB distal with rounded distal without but low spines; broadly of tapering outer each not subterminal segment indistinct designated subdistal spine often sharp, with entire a lined uneven part with edge 944a., F. (as ZMB Tanzania Mombassa), ZMB Kenya, 7 Stuhlrnann, 9445, Wembere by 5017, Bott, coll. Dar (as Downloaded By: [CDL Journals Account] At: 20:24 26 August 2007 juveniles, D. FrG. , East d 2 sufficient Biedermann. 298, Lake ~, imitatrix Remarks. 1. cl Mombasa atluaudi, of Malawai (A) 21.0 mm, aaae () etcea Sae=50 mm. 5.0 = Scale chela. left (C), carapace; reason Deckenia ZMB (type coll. 1 lectotype male, lectotype d, (as This (as 17846, 23.2 to F. locality Zanzibar, locality cw mitis, Nyassa Mombassa), regard Thomas, species 40-0 mm, coll. male, Revision mm Lake), 7 t as it cw was II cw 9, 11 42-8 mm, c136-2 cl East cl 40-0 ram, c133.1 a Kenya, May 33.1 described Malawi, of 19.8-28.5 separate Africa, Tanzania) Deckeniidae Ortmann Deckeniidae mm, 1903. ol C. coll. coll. 1 R. species as mm, 9, mm, Methner (Bott, a ram, cw II variety Alluaud, NHMW MNHN-BP East MNHN-BP 32.3 despite 1955; Africa, and mm of 2886, 1904. Table its D. G. cl C 152. views dorsal (B), (A), 298; (B), (C), .4 external 26-3 imitatrix Zenker, Goetze. Ukambasin, Sumpf, Ukambasin, 1 1). 6, ram, ZMB March similarity 1 but MNHN-BP Seychellum 6, there 1 15425, 1914. 9, 585 to is 4 Downloaded By: [CDL Journals Account] At: 20:24 26 August 2007 Ft~. 586 2. B plastron; palp endostome regions Deckenia of mandible. dra view); (dorsal (G) mitis. and right antennules; Male, Scales: carpus cw (B) of A, 40.0 (D) cheliped rna and frontal B, P.K.L. mm, left third left D-G cl (dorsal = 33.1 5.0 Ng orbital maxilliped; ram; mm, view); et al. regions MNHN-BP C, (H) H-J (E) right = (frontal left chela; (F) chela; left I-I 1.0 mandible, 298. mm. view); (A) frontal m~wgmb~ with palp; anterior m iq m (C) and orbital epistome, sternal (I) (J) Downloaded By: [CDL Journals Account] At: 20:24 26 August 2007 FIG. 3. view); (E) last Deckenia l A (G) ambulatory (D) dorsal (E) mitis. left view. Scales: view. leg; Male, G 1; (C) Revision (F) (G) cw right 40-0 A-C left last mm, of G 1 = Deckeniidae ambulatory c133.1 5.0 terminal mm; E mm, D-H segment; propodus MNHN-BP Ortmann 1-0 = (H) mm. and left 298. dactylus G2. (D) G2. (A) abdomen; (F) (dorso-marginal ventral C (B) view; fight 587 Downloaded By: [CDL Journals Account] At: 20:24 26 August 2007 588 Carapace Table tMandibular Third Endopod Orbits Carapace Carapace Anterolateral Postorbital Epigastric Carapace maxilliped Carapace Posterior Carapace Antennae septum interantennulary (dorsal margin Posterolateral Cervical tAntennules tProepistome striae 2. maxilliped an surface) grooves t of carapace depth convexity surface regions lateral shape Differences cristae are cristae first palp margins and margins regarded between as elongate, basal terminal cylindrical frontal Deckenia fossae position barely ischium without ischium chimney-like basal folding very very glabrous, appears from margins, and frontal highly keeled laterally of longer very indistinct wide very absent not nearly antennules vertically and appears distinctly arcuate not absent especially frontal discernible visible the longitudinally P.K.L. deep convex wide, shallow, dorsal segment segment ovate visible almost compressed than view; genera almost lateral strongly flattened, palp not distinctly smooth converging margin significant). in distinctly elongate, supraorbital 0-5 view, laterally visible structure simple, shape, from vertical, Deckenia Ng slender of in width sulcus et by al. and Seychellum basal terminal but nearly stout distinctly frontal ischium 45°), position relatively, folding Seychellum width normal, distinct weakly distinct distinct obtuse rough, not margin ventrally not nearly compressed margins structure frontal visible somewhat sinuous, of fossae very wide very subparallel sharp, sharp, flattened segment antennules distinct deep, laterally basal segment of distinct distinct quadrangular flat oblique ih scattered with tubercles from views, and obliquely arcuate with but palp < appears still frontal or oblique flattened bilobed, dorso- twisted short, 0.5 segment (those supraorbital sulcus keeled by basal dorsal clearly shallow normal, very (c. in marked and by Downloaded By: [CDL Journals Account] At: 20:24 26 August 2007 projecting Antennules 2-segmented, interantennular prominent; frontal and fold designation. Diagnosis. Type species. Type dorsal views, dorsal Ambulatory Table Female Male Sternum Carpus exceeding half ~-G2 margin abdomen 2.--Continued slightly of abdomen orbits folding Family basal cheliped and Superfamily legs septum Carapace peduncle infraorbital forwards, normal; Deckenia the segment obliquely, GECARCINUCIDAE length triangular, Revision udaglr rugose, quadrangular, on front lateral GECARCINUCOIDEA Deckenia alluaudi usually hidden, by of piece piece blade-like propodus stout, segment, segments articulation segment a segments margins lateral distinctly male narrow, 4 sternite than segments articulation abdomen long, distal 2 inner surfaces flattened, laterally 05 length 0.5 > margin, of upper gently sharp c. Seyehellum sternite carapace, larger elongate abdomen reaching abdomen 45 distinctly vaguely distal segment of terminal lobes moves not spines edge ° convex smooth, 6 not A. tip obliquely moves Deckeniidae 445 triangular, stiff, and stiff, from partly hidden partly one; angle visible; between between Milne sharp segment very basal of dactylus forming laterally as very abdomen of longer rlbt with trilobate endopod gen. line; segment horizontal; endostome as Rathbun, one with low, Edwards one positioned, nov. 7 regions Ortmann rounded. compressed. of 1 distinctly Rathbun, articulation between articulation about sternite Seychellum not length emns flexible, segments movable segments articulation of male than distinctly distal freely several inner normal, propodus distinctly 4--6 segments Lateral exposed, segment segments segments sharp segment, surfaces flattened 1 1904, adjacent and epistome sharp st segment well straight; median clearly maxilliped elongate abdomen Bouvier, distal Antennae granules segment 0 < movable of sensu smaller margins 4 spine and spine not very defined, 6 laterally distal tip bilobed, sternite freely concave, on broad, flexible shorter and 33 1904 to completely 7 visible 7 between angle with angle distinctly Mandibulary visible barely rounded abdomen infraorbital lobe rugose basal lato dactylus reaching part 1893, of compressed slender, cristae with subtruncate, from discernible, by smaller present frontal lateral sharp, angle. palp 589 by Downloaded By: [CDL Journals Account] At: 20:24 26 August 2007 and African/Madagascan probably appear the concave. Seychellum broad, margins 590 the the Seychellum, have morphological externally, will eacncde however, Gecarcinucidae the characters endostome, dated Seychellum those shallow and suggested with slender associated dorsal not, (structure interpretation segment of a segment appearance segment appears structures. simple Deckenia, form The Zoogeographical implications. Zoogeographical species mandibular Remarks. The Etymology. Familial position Familial Distribution. The carapace, by as and the probably arisen of within a view, male the to result, to chelipeds position but genus potamonautids structures Neotropical sinuous; of being shorter all Terminal terminal 1 artificial be of that system with be The and partially they richness its is as however, abdomen via distinct. of appear chelipeds with although any closer the more which bilobed. (see well epistome, their freshwater Seychellurn highly very having respiration, characters Although have palp suggest ovrec. While convergence. share than entire of of The of the outer segment taxa and and Familial position Familial Known as plesiomorphic zoogeography of to the to the to Seychellum in classification hidden covers long was Suture , edges Gecarcinucinae. reaching to the of elongate possesses compressed genus concealed This very" the and be the subterminal only aeal flattened laterally 1st extant and (especially the surface Seychellum. endostome be tubiform a Deckenia crabs and highly West area. such abdominal is legs) is character epistome, only requires and which and similar part few between by close is 6 established that regarded whip-like. subfamilies to basal abdominal named the first Rodriguez carapace, as part African Globonautinae, African in so are from of of of about in derived, proposed P.K.L. in the is is endopods antennae affinities similar the the many segments the them to ischium mouthparts, typical that part evolved and and also of not The structure the present segment, of sternites segment endostome the the subfamilies after Gecarcinucidae The mandibular as the 2nd one-third Seychellum). the Seychellum bilobed. 1 carapace by a evolution can unusual for st hydrotelphusines), granitic monotypic condition lateral legs. notably matter in Ng noted 18: 55) (1986: segments. median for by two mandibular segment maxillipeds, and the the of of of in both the of be it compared Bott 3 et freshwater tip (in the and 3rd the G 1 G genera The Seychelles epistome, carapace, and as clearly Gecarcinucidae of eventually. that al. of margins In features both in and rounded. and the part of 1 (1970), as clearly well palp radiated sternite. maxilliped 2 some st in contrast, 4 as pseudothelphusids are 1st freshwater the for The however, based however, genera. recognised maxilliped Deckenia interrupted smooth general be referred seems 1st sexes) clearly well. palp defined as however, to and male it is very the bilobed uncertainty. crabs, of that of and is demarcated; into G2 maxilliped Seychellum, epistomal islands. Male from of being the South still like moment. This segments The the is to different Consideration lateral it abdominal features of discernible. and separate superfamilies. gently Deckenia those completely crabs and as be cannot Seychelles. and no seem terminal terminal India lal visible clearly abdomen Deckenia to by medially, gives suggest problem rounded yet 2-segmented, African Gender rather Seychellum separate other. a expansion Bott and Ortmann is on of convex, new be are (Ng, G2 on of in 4-6 with poorly be as Deckenia Deckenia work is apomorphic endostomal Seychellum segment isolated. the appearance segment segment long, It well (1970) In a accommo- all triangular, subfamily hidden neuter. and similar sternite carapace, distinctly however, 1988). the with affinities families, different of the basis mainly clearly known (1902) sulcus as of could distal south distal other from with case the the the are are the by In of of of of to 4 Downloaded By: [CDL Journals Account] At: 20:24 26 August 2007 possess India'. supposition. Africa northeastwards (1984: a than only islands (1988) (Braithwaite, and which Rodriguez, million years million freshwater the only the condition morphology, structure separated data), brachyuran the The potamoids as ucoid Ng, thus Palaeotropical and Solomon into and the another are terminal 1981; species 1988). de evidence The The The Freshwater Gecarcinucoidea end found basis Europe India facto 1988)) rarity Southeast limestone perspective. group 2 essentially but Audley-Charles helps contain taxa 3) Gecarcinucoids The indicate for which elements is presence interesting in evidence of segment is commented some Islands. the had must of isolated only and South 'micro-continent' are the Palaeotropical of are Asian, of some that indeed (Bott, groups put 1986). presence the Brachyura ago. isolated 3rd freshwater 1984). been gecarcinucoids, straddles difficulty absent). Gecarcinucoidea. Cretaceous or Asia, some in have 120 the that some have Africa published of of oceanic for of They 1955, 1969; 1955, 65 Central maxilliped The in point about a in freshwater million Both connected fossils (as a a India the been (Gecarcinucidae, synapomorph. Audley-Charles 100 and West that occurring the a the of gecarcinucoid of years million much oceanic et are Crabs bilobed African Gondwanan and are the mandibular of are the al., crabs, Seychellum million evolution Eocene groups into basalts, '...it Gecarcinucoidea Revision especially and had present are and forming years Africa present fossil area Madagascar certainly problems older and 1981; with Glaessner, known and crabs supports the in islands the South separated is beginning terminal from and Potamonidae) ago between The has years the possible have some distribution and biota, data, then, (Globonantinae, Sunda a Rage, G1 of in (and it of crabs evolved palp distribution. genus bilobed as east abundant past. (Stoddart, been America. much only present in does appear which et of Deckeniidae this southern Parathelphusidae ago. the structures. Gondwanaland oee, diverged however, 55 there before segment with the (Gecarcinucidae) finding) freshwater al. is from of 1969). 1988), and East that the of The from is separated million theory (Seychellum) their older The northwestern and in (1981), are terminal Seychelles supposedly the with discovery ancestral of evolved seems au Shelves, Sahul on India Madagascar Seychelles Africa/Madagascar In the the China Seychelles This Neotropical composed freshwater crabs distribution. 1984; Tertiary than freshwater the of that granitic to Africa, a years Since Ortmann Upper 2 Gecarcinuidae) crab or the bilobed be from Braithwaite absence main Indian continents to segment this. Africa, with but from Europe disintegrated links Braithwaite, a that mandibular ae been have (includes Bank ago (P.K.L. ago the in evolution India, synapomorph for Africa Tertiary one in are islands is (Bott, the Bott of Bank crabs which a the considerably marine and Seychellum fossils result the unusual Pseudothelphusidae terminal to bilobed however, The Madagascar, continental absent group India during northern of strongly Seychelles, ranging both (1955) separated, moved Tethys 1960, was and subcontinent the (1984) Pseudothelphusidae [of Sundathelphusidae; from of and and is ancestors (Bott, an (Audley-Charles, palp and of Madagascar Ng, from mandibular because mandibular Seychelles] 1984). continental the almost well South segment postulated cannot 1965). 'explosion' zoogeography through have India, northern gecarcinucoid Australia progressively supports Sea is Madagascar/ late is unpublished n Tarling and rocks in 1970), known. a Japan Seychelles the if a present gecarcin- certainly about a carapace group Tertiary. Stoddart America between the it Most both bilobed be wholly (where of rather South is India used palp drift palp with (Ng, palp also (see this and that and 591 the the On 65 of of of of in Downloaded By: [CDL Journals Account] At: 20:24 26 August 2007 592 FIG. transitional mandibular (Madagascar). 4. F-H (A) nenls (E) antennules; view); (IO), maxilliped (BS), ~ Seychellum e~ c~e~ frontal 5.0 = edge e,~ palp (C) t~ forms ¢~ This of mm; (outer view); (H) view); (outer and rna ad orbital and frontal from alluaudi. supraorbital (AN); orbital ventral would being B, those D, Lectotype (F) E = E regions view imply observed with margin left 1-0 of endopod that P. third (frontal mm. a left regions male, simple (SO), K. A endostome the in maxilliped; L. of cw antennal view); potamoids the Ng terminal right (dorsal 4 2.8 et Hydrothelphusinae I (B) mm, (EN) 1 st al. peduncle (G) iw; (D) view); frontal maxilliped segment (Potamidae c136. showing endopod G 2 and (AP), mm, is edge (inner view). (inner epistome, orbital and basal MNHN-B partially and of exopod (Potamonautidae) i'i. regions segment infraorbital Potamonautidae) H endostome supported P Scales: 152, of (sub-dorsal of right antenna Praslin. margin A, and by 1st C, Downloaded By: [CDL Journals Account] At: 20:24 26 August 2007 FIG. 5. Praslin. in left (outer 152, ecelm alluaudi. Seychellum entirety). carpus Praslin; view); (A) of .?~" Scales: right (D-G) cheliped; (E-G) .I 2nd A-C, various (H) (A-D) maxilliped; Revision (J) I-I B female paralectotype, estimated paralectotype, female anterior H-K views (I-K) = of 5.0 sternal plastron; (K) of (B) lectotype Deckeniidae right mm; right d palp D-G mandible male, of 1-0 = mandible; Ortmann cw 42-8 mm. (inner male cw mm, abdomen (H) view); I 30 c136.2 right D mm, v (C) 3rd (segment mm, MNHN-BP right maxilliped; MNHN-BP mandible I( 1 shown 593 19, (I) Downloaded By: [CDL Journals Account] At: 20:24 26 August 2007 594 of evolved America. already FIG. the 6. (A) (A) Seychellum present mandibular well (B) (C) left ventral view; ventral over G1 then alluaudi. ; 120 (C) (D) palp in million Gondwanaland, (B) Lectotype left (Gecarcinucoidea (D) G1 h~ ." years dorsal terminal P.K.L. male, cw ago view. segment; before Ng as 42.8 Scales et crabs and mm, al. the (E) ",.,.o 1.0 = c136.2 Pseudothelphusidae) with separation left G2; mm. bilobed mm, (F) MNHN-BP tip of of terminal Africa G2 J distal E 152, and and segments segment. Praslin. South were Downloaded By: [CDL Journals Account] At: 20:24 26 August 2007 FIG. 7. ..., view); (segment infraorbital SeycheItum (C) 1 orbital margin partially covered alluaudi. regions (sub-dorsal and Revision Male, antenna by cw (sub-dorsal of carapace). 51-8 Deckeniidae view); mm, view); Scales cl (D) 4311014 Ortmann anterior (B) frontal = 5-0 mm, mm. sternal SMF and C plastron; orbital 12926, regions La (E) Digue. abdomen (frontal 595 (A) Downloaded By: [CDL Journals Account] At: 20:24 26 August 2007 596 FIG. 8. right ventral Seychellum G1; view. (C) alluaudi. C (D) Scales right A, Male, G1 B, ii: terminal E = E cw P.K.L. 5.0 51-8 mm; segment; mm, Ng C, cl = D et (E) 43.4 i B al. 1.0 right mm, mm. G2. SMF (A) 12926, (C) E dorsal . view; (A) (B) (D) (B) Downloaded By: [CDL Journals Account] At: 20:24 26 August 2007 bilobed, Mandibulary upwards, proepistome compressed on angle with cristate, epibranchial part short. running straight. views and sharp, form, converging ending MNHN-BP youngd, m, gently and striae cristae cristae distinct towards Deckenia cw La mm, Deckenia anterolateral, (ovigerous, Seychelles, 6.8mm 535.92. upper Ortmann, 219; Digue, coll. Orbits, 51.8 Description. Material projecting infraorbital small 2 cl Seychellum lined on of Interantennular but convex acutely separated as Borradaile, longitudinal (NHMW ~?PARALECTOTYPE separated grooves, lined subparallel 36-2 H-shaped M. smaller mm, edge each . 45 ° c. Alluaudi cristata median cw 4°20'S basal sharp, sharp eyestalk with Indian Ackermann, posterolateral egg 19, 1902: by teeth; narrow 15-0 examined. mm, pterygostomial, pulp with cl of side, on forwards triangular, same expansion segment large margin, from 43-4 size endostome and fold Rathbun, the margins cervical grooves shallow grooves cervical 7518), part acutely by 55°50'E, 306; Rathbun, ram, A. alluaudi gastric groove; epigastric 1907: Carapace quadrangular, broader by frontal MNHN-BP small, Ocean, other and 2-segmented, and but distinct ridges flattened Milne c. data exceeding rounded mm, triangular, horizontal, septum deep cl cornea 3-0 close of 63; Montagne distinct; lateral obliquely areas partially triangular 12 sharp 12-0 margin as LECTOTYPE~Of 1894: not Revision margins; posterior margins; truncate of SMF coll. of mountain, Edwards mm), (A. Haig, adjacent to on May lectotype. -hpd groove, Y-shaped notch and to subhepatic D. endostome, distinctly separated broadly granules, granules, well mm; pitted 1905: each 23. granules, 152, Milne frontal W. half margins 12926, alluaudi, finely almost 1984: (Figs cw basal 1979. basal hidden positioned, developed. marking Brulee, lateral of 1 exo-orbital Abbott, and rsi island, Praslin pl. length or aide, young c. 250 c. 20.2 eknia Ortmann Deckeniidae Edwards triangular. 2 infraorbital margin, 125, granulated, gently 29 clefted 1B, parts antennular posterolateral Bouvier, La segment flat SYrCrvpE and cristate. per serrated, appears by lobes; D. lateral parts lateral mm, fig. but the Seychelles, carapace Digue, and of m, C, $, medially, 132. beginning Acc. roof sub-branchial alluaudi of margin Antennae 5; rugose; clearly larger distinct, cw coll. M. coll. 4-8) medially; outer frontal and tooth; postorbital and cl posterior supraorbital Rathbun, postorbital 1893: ~? Endostomial 78. 1 27085. Antennular of stout; 24.0 from gently from angle, 17.2 4°20'S than appears olD. segment Seychelles, Bouvier, frontal margin, crushed, one. one not of infraorbital visible regions regions (present 325, fig.??; Ortmann, 325, of coll. Ackermann, folded mm, running mm long, compressed terminal cristata, anterolateral not carapace swollen; 1906: cervical grooves, cervical margin being Endopod postorbital epibranchial 55°50'E, juveniled, regions cristae broadly Hadl, cl margin (juvenile), cristae stout. clearly high from fossa 1893) defined, lined pad and upwards estimated ridges 20.5 72, convex designation), almost ol c. coll. weaker cw of 27 sharp, margin segment frontal, Fig. but very covered Epistome triangular, frontal and frontal oblique, ram, of visible; finely 12 with epistome by peduncle mountain, comb. nov. comb. continuous 34.2, October well regions margin dorsal cw May demarcated 124, 1st frontal and longitudinally tooth USNM wide, well defined, Alluaud, SMF and cw 6-7 postorbital, sublamelli- granulated, developed, cl 7.9 maxilliped Bott, with epigastric 1897: distinctly flagellum gradually 1979.1 inwards; 28.5 set surfaces cw distinct, 30 arcuate, narrow, narrow, shorter. oblique median twisted located 91 1 1991. margin mm, almost 12925, c. 250 c. dorsal 8064, at an at large 1955: mm, with 42.8 mm 314; 597 no. by c~, cl Downloaded By: [CDL Journals Account] At: 20:24 26 August 2007 The the region S. males Praslin. onymized The the exo-orbital tubercles smaller Praslin and is S. size-related. and G2 almost furrow consecutively pair reaching long. smoother lined closed; are segment segment fingers between clefted; subdistal convex, lateral 598 opening convex, separated slender, not alluaudi, alluaudi, types Remarks. It Distribution. Terminal Ambulatory females, long; Male Sternal Male form La exact locality S. similarities longest. with is known, of alluaudi. is (A. edge straight; on 7th on longer Digue than difficult merus just The sternite lateral median forming an trie 4 sternites 1 7 chelipeds of spine. (against distal granulated Seychellum abdomen of with by sub-branchial Milne sharp concealed teeth raglr lateral triangular, imaginary plastron D. but a species a below The larger and of the young and the distinct Dorsal the (present than smaller sternite. cristata S. approximately margins The Propodus there segment front. distal legs however, 4 to being sulcus types granules. Carpus granules. Compared Edwards and the subterminal alluaudi antennae, 3 only from funnel-like broad, The species base asymmetrical, ascertain distinct palm, triangular, male and species relatively important (against broad. margin does previously by groove; from segment line Third smooth of sharp available confirm record). Male female which shallow of sinuous, 5, elongate, carapace, and and S. male agrees lined by antennae are joining not tubercles and Mah6 to antennules, alluaudi. Sternites if described maxillipeds Rathbun gonopores granules segments of dactylus entirely suborbital margins Bouvier, Rathbun's evident, sternites exhalant long, appear (not hexagonal; the the of is sharply male lateral abdomen Rathbun's with 6 but merus known information with inner known D. outer P.K.L. and the with become young but shorter but types but granulated) (covering segments distinct; cristata, present), gonopods numerous to be posterior (1906), granulated). S. 7 ventrally 1 margins posterior surface posterior of and almost surfaces bent 1893), 3 as 1 cristate, structure only coxal. medially epistome, only and regions, of alluaudi material reaching male large G 1 and forming synonymy Ng D. ischium available any it S. outwards, exopod clearly being from although and 2 not is from who Mah6 the 4 than cristata et alluaudi, deeply straight, (NHMW and part spine are major teeth granulose and of completely tentatively fused, to gently and al. distinctly just region (1894) with interrupted, the in examined vaguely the to These segments the not only basal endostome of it. 'Seychelles'. rectangular, dorsally (Borradaile, demarcated; subterminal most lateral stout, on inner and (1906). and beyond about differences the concave, neighbouring infraorbital Palm gently Seychelles, ovigerous, available by medially ocv endostome, concave serrate, tip the D. between 7518) of segment, base denticles. differences compared to rugose. the Rathbun, flattened long D. triangular assigned rounded; anterior cristata one-third parts fused, keeled, the of Both 4-6 antennal tapering distal sternite of key cristata from and outer larger types with flagellum 1907; outer interrupted, for A the the between clearly is distinctly of from shelf tip aspects, re-examination trie 2 sternites half or serrated, Margins mouthparts. angle differs still island comparison Mah6 with chelipeds; epibranchial there Rathbun's 1894, surface anterior are short of of peduncle), structure rounded. present to blade-like, 2nd chela 7 were surface the of both substantially with without sternite, rounded visible. regarded those and row D. present. until adult until belongs of the in but islands including a syn- was collected concave; of swollen; dactylus segment laterally strongly species. efferent Praslin. cristata record) median part having frontal gently merus and suture sharp when types from with near The just any and tip. as of of of to of 3 Downloaded By: [CDL Journals Account] At: 20:24 26 August 2007 BOTT, AUOLEY-CHARLES, lacks mandibular bilobed Mah6, Borradaile tip the has ABELE, References University AUDLEY-CHARLES, B BOTT, (Fig. for difficult larger aspects: brown, populations certainly of the outwards) her Acknowledgements allowed edged. Vannini BORRADAILE, sub-branchial observed and O'rT, the types of hospitality The The infraorbital Colour. Paul studies been 7B, a R., . 1965, R., . 1955, R., than basal udm ainl Hsor Ntrle Paris, Naturelle, Histoire nationale Musdum Musre Whitmore , (Zoology) 2, Mesozoic South African South Expedition and (Oxford: the 13-18, L.G. 2200 H.K. distinct the the (Fig. authors to dismiss. us kindly shared kindly SMF 1960, ofD. Clark's C) size-related. may partially and terminal Classification the access of (1907: and exo-orbital ventral surface ventral palp antennal will L.A., feet, Yip Royal on (against Fig 8E) h carapace The Crustacea Singapore. region lectotype cristata the specimens during Clarendon), be Die FELGENHAUER, Die cleft margin and are (ed.) to infraspecific of probably 1-4. M.G., (National helpful M.G., and outer to due (not 1907, 13, 63) du Siisswasserkrabben the Stisswasserkrabben Once the segment grateful supported Cenozoic, (Fig. their segment of Wallace's their 3), 63-68. Congo Beige, Congo for his Cascade Indian noted to The tooth entire). HURLEY, (Decapoda): and of specimen male margin Land 1981, the the more comments 7A-C) comparison. size knowledge collections from iig Organisms Living Revision pp. visit Life: Results Life: prove and University carapace, differences shelf, to is Ocean surface E., sub-branchial that from directed and Geological 9-23. is in and more Dani~le specimens variation, by However, Line to of River, A.M. chelipeds La 1982, more T.C. and to freshwater S. the is the and Praslin (cw RP900360 age. Potamonidae, in C.3.3., of Digue be acutely triangular and alluaudi regarding almost and of the MNHN. of and yon Decapoda, Whitmore yon 1905, G2 strength distinctly concave Deckeniidae shape Hans Mahr, of of of Guinot Deckenia Characters in the lt Tectonics Plate history SMITH, shelf basal the kindly Afrika Singapore) Madagaskar the from 1,209-352, being the specific significance. specific resemble the Transactions (New regions Decapoda. identical Gruner Lund small of '...was adult 800 51.8 Raymond has of the to differences for segment (Fig. G1 La Digue (ed.) A.G., the in S.S. in in of und 2, upwards white helped York: the with the Hanstrom, Brinck nvriyEpdto in Expedition University feet'. 2 loan manuscript 37 the versus Ortmann specimen (and basal are (ZMB) male like distinct ihre 7A), S. Watlace's exo-orbital to took 1981, obtained l 1-30. pls (2); (Cmstacea, (Fig. Parkes first Reports region the with McGraw-Hill), more of of Ofr: Clarendon), (Oxford: alluaudi has with that the Manning Stammesgeschichte, especially and from antennal 42-8 the 335-350, the (Fig. the first the Continental and 7E), author observed a median small degree of (ed.) our of Wallace's of ina Society Linnean Praslin nltd the inflated, G1 is G1 distinct (NHMW types of photographs. ram) are Line author. La on Michael the 8A-D) the Decapoda), angle, the many but crwHl Synopsis McGraw-Hill (USNM) gratefully dark Morne Digue and segment lts 1-4. Plates from much infraorbital straighter, and and of of the rounded Percy become cleft differ pp. movements Ruderbeck between Lipke D. inflation queries. the granulation (not flecks. Plate T~irkay G2) 7518) 1950-1951, the 296-326. is alluaudi larger Line, Seychellois, median and Sladen differences kindly Annales du Annales are Bulletin somewhat in The pp. of obliquely Holthuis' acknowl- are tubercles available Tectonics National with appears London, is margin several in almost (SMF) Marco 24--35. of types. the (eds.), study more in Trust dark T.C. part sent 599 and the the the on du 7, 2 Downloaded By: [CDL Journals Account] At: 20:24 26 August 2007 RATHBUN, BOTT, HILGENDORF, BOTT, GLAESSNER, HAIG, TARLING, ORTMANN, NG, ORTMANN, ORTMANN, RAGE, NG, MILNE BOTT, RATHBUN, 600 BOWMAN, BRAITHWAITE, RATHBUN, HARTNOLL, RATHBUN, RODRIGUEZ, HmGENDORF, STODDART, P.K.L. P.K.L., J., . 1969, R., R., . 1968, R., Abhandlungen olgsh Verhandelingen, Zoologische ecebrin biologica, Senckenbergiana auel, Paris, Naturelle, Part auel, Paris, Naturelle, Museum, chichte. rs) pp. Press), erde, and ecology rs) pp. Press), Audley-Charles pp. auel, Paris, Naturelle, 9, Decapoda: Cainozoic, ancient Oxford naturforschender (London: Academic), (London: des Stoddart and and 256-372, Shinglee) Ost-Afrika, (Hilgendorf), The Biology J.-C., 1-58. EDWARDS, 1984, 409-453. T.E. 1970, M.J., D.H., A.E., A., M.J., M.J., M.J., 123-139. D.R., B.R. K.L. R.G., and ecology ao von Baron A., R. M.F., G., Natur 1988, F., F., 1988, CJ.R., 1896, rhooa 4, Arthropoda University and geography, of Land Eine NA1YANETR, (ed.) Praadaption, 1897, 1986, Die 1894, 1902, 1869, Heck 1898, Parathelphusiden McMahon 17, l 17. pl. pp. 1904, 1984, 1905, 1988, 1906, 1988, Brachyura: in the 61-77. 7-54. A. 1969, Decapoda, The 4, ABELE, und of of , Das M.G. Stisswasserkrabben Annales Revision 1-7. i-viii, and (9), and 1984, ecels Islands Seychelles the Crustacea, the der The Crabs Centers Ueber Die h ecels Islands Seychelles the (eds), Carcinologische Freshwater Evolution, and Scientific Museum, Les Les Les e Decken, der Gondwanaland Paris, 4, 7, 4, 4, 8, 4, system Freunde freshwater 37, Press), ecebrice Ntroshne Gesellschafi, Naturforschenden Senckenbergischen Audley-Charles BOUVIER, Land-und geographical L.G., Proceedings A. Geology 1-156, (eds) P., crabes crabes crabes Revision from Biogeography eine pp. evolution Potamidae, pl. uSine ntrle Zoologie, naturelle Sciences du 33-122. 159-323, Geological Hallam der of 4, 6, 4, 1993, der 1982, Tethys studies 1. radiation 1-30. 99 pp. neue Biology systematics, the zu Berlin, zu Potamoidea aus in and Crabs figs Decapoden-Krebse, 49 d'eau d'eau d'eau 225-312, E.L., crabs of Stisswasser-Dekapoden (6), Vol. 284, New 255-273. Indian R.C. Deckenia (eds) Classification Hinterindien (5); of Gattung the und ecology distribution pls 1-63, of studien, in and von and Gecarcinucidae 266-275. (The Society Deckeniidae of 1, douce, 1-117. douce, of douce, and 1893, of Seychelles, Moore of and the the 403-422. 13-22. Gondwana bediedlungsgeschichte of ytmtc, The Fossil Systematics, Peninsular Ocean, 1868, Europa, Land terrestrial the (The freshwater the 4 pls and Seychelles, Hague: A. rsae, rsaen Issues, Crustacea, American recently und Kurzschw~inzigen of colour mtti, Sitzung-Berichte imitatrix, Sur Seychelles Hallam (eds) Zoologische 9-18. ovle Archives Nouvelles of Nouvelles the Seychelles Islands the Seychelles (ed.), ovle Archives Nouvelles geographical evolution Hague: 2. Crabs Parathelphusoidea of (Crustacea, Proceedings of America, une Asien, freshwater in W. and pls. the Zoologische described Ortmann Treatise vertebrates Malaysia crabs D.R. and Parathelphusidae) hlspia Society, Philosophical esprce Junk), (Cambridge: in recent W. Tethys and Ostafrikas, Australien D.R. Archives of Stoddart 15, in Junk), 2, Gondwana Jahrbucher distribution, Decapoda, on neighbouring the decapods pp. the of nouvelle R399-533. Crustacea, Krebse freshwater Stoddart 325-336, and (Oxford: der Invertebrate Paleontology. Invertebrate the Record during Jahrbucher Neotropics, 17-38. Indian pp. (Crustacea, du du du (ed.) Stisswasserkrabben Singapore, United States National States United Cambridge und Die (The aus 1-15. and Musdum Musdum Musdum and u genre du (ed.) the Parathelphusidae), and Biogeography Oxford (Systematics), in Thierwelt ihre l 8. pl. in crabs den Hague: Ocean, der 3, 526, W.W. Tethys its islands, D.E. from Mesozoic Biogeography Biogeography (Systematics), 51-67. 41, Stammesges- Sammlungen in bearing Gesellschafi (Singapore: Decapoda), (Crustacea: University University d'Histoire R.H. 1-338, d'Histoire d'Histoire Bliss W. Thailand, Deckenia Burggren 267-400. (Oxford: in Deutsch in Junk), M.G. Gore upon D.R. (ed.) and and der pls 10,