CRUSTACEAN RESEARCH，NO .26: 16-25，1997

Cinetorhynchus fasciatus，anew shrimp from the western and central Pacific (: : )

Junji Okuno and Hiroyuki Tachikawa

Abstract. - A new rhynchocinetid cies (Okuno，1997): C. concolor (Okuno， shrimp， fasciatus，is de- 1994)，C. erythrostictus Okuno，1997 ，C. scribed and illustrated from three male hendersoni (Kemp，1925) ，C. hiαtti specimens collected 合 omChichi-jima Is- (Holthuis &Hayashi ，1967) ，C. stri αtus land of the Ogasawara Islands，Japan ， (Nomura &Hayashi ，1992) and C. reti- and Oahu of the Hawaiian Islands. The culαtus Okuno，1997. From the Atlantic new species closely resembles C. hiatti Ocean，two species，C. m αnningi Okuno， (Holthuis & Hayashi) and C. rigens (Gor- 1996 and C. rigens (Gordon，1936) ，are don) in the armature of the ambulatory known (Okuno，1996). pereiopods，carpi and dactyli in particu- In early 1996，one of us (HT) collected lar，but maybe distinguished by the com・ two specimens of an unusual form of bination of the fourth abdominal somite Cinetorhynchus 合omasubmarine cave on rounded on the posteroventral angle，the Chichi-jima Island，Ogasawara (Bonin) stylocerite not extending beyond the end Islands，southern Japan. Later，Mr. John of the antennular distal segment，the P. Hoover kindly donated to us an addi- meri of the third and fourth pereiopods tional specimen of the s出 ne species col- bearing two to four spines on the lateral lected by himself from asubmarine cave surface，the second maxilliped bearing a at Oahu，the Hawaiian Islands. In the developed podobranch，and the distinc- morphological aspects，the specimens ap- tive coloration. Amodified key 10 species pe町 close to C .hi αtti and C. rigens，while of the is proposed. in coloration they are similar to C. striatus. The material apparently repre- Introduction sents anew species，which is hereby de- scribed and illustrated.

τもe genus Cinetorhynchus was origi- Thetypes 訂 e deposited in the Natural nally established by Holthuis (1995) as a History Museum and Institute，Chiba subgenus of sensu lato. (CBM-ZC) and the Bernice P. Bishop Mu- Subsequently，Okuno (1997) elevated seum，Honolulu (BPBM S). 明1e method of 也前旬xon to full generic rank on account measurements follows Okuno (1 997). of the indistinct rostral articulation，lack Carapace length (CL) shows the postor- of supraorbital spine，presence of three bital c訂 apace length. teeth in midline of the c町 apace posterior to the rostral articulation，an acutely pointed posterolateral angle of the fi 此h Cinetorhynchus fasciαtus new species abdominal somite，and the ischia and (Figs.1-4) meri of ambulatory pereiopods armed with two rows of spines. To date the Indo- Type Material. - Holotype. Male (6.5 Pacific Cinetorhynchus contains six spe- mmCL ，CBM-ZC 3629)，2T02.2'N ，142 。 NEWSHRIMP OFCINETORHYNCHUS 17

13.0'E，Tenno-ura beach，Chichi てjima 1s- ing posteriorly to upper orbital margin. land，Ogasawara 1slands，Japan ，5 m ，17 Abdominal somites (Fig.2C )covered February 1996，coll. H. Tachikawa.P 訂 a- with fine striae; pleura of first 3somites types.Male (4.8 mmCL ，CBM ・ZC3630)， broadly rounded，that of fourth somite same data as holotype; male (9 .3mm CL ， with posteroventral angle; 日fth 0 0 BPBM 811318)，20 50.0'N，156 55.0'W， somite with small but acuminate postero ・ Lanui Lookout，Oahu ，Hawaii ，5 m ，25 ventral process; poster叫 ateral margin of January 1997，coll .J .P .Hoover. fifth somite with acute spine directed pos- teriorly; sixth somite 0.58-0.62 times as

long as carapace，with 1acute postero ・ Cinetorhynchus fasciαtus new species ventral and 1strongly hooked preanal (Figs.1-4) spine.Telson (Fig. 2D) 0.65-0.73 times as long as carapace，1. 13-1. 21 times as long Type Material. - Holotype. Male (6 .5 as sixth abdominal somite，with 3pairs of mmCL ，CBM ・ZC3629)，27 ・02.2'N，142。 dorsolateral spines; posterior margin end- 13.0'E ，Tenno-ura beach，Chichi-jima Is- ing in acute triangular process flanked by land，Ogasawara 1slands，Japan ，5 m ，17 3spines on each side ，median spine February 1996，coll .H. Tachikawa. P 訂 a- nent. types. Male (4.8 mmCL ，CBM-ZC 3630)， Eye (Fig .2A) with comea large，globu- same data as holotype; male (9.3 mmCL ， lar; stalk much more slender than comea. BPBM 811318)，20 ・50.0'N，156・55.0'W， Antennular peduncle (Fig. 2E) reach- Lanui Lookout，Oahu ，Hawaii ，5 m ，25 ing proximal third of rostrum;stylocerite January 1997，col l. J.P .Hoover. reaching at least midlength of distal pe- Diagnosis. - Pleuron of fourth ab- duncular segment but barely extending dominal somite rounded posteroventral- beyond that segment; proximal segment ly .An tennular peduncle with stylocerite armed with distolateral spine reaching reaching at least midlength of ultimate proximal third of median segment and segment but not extending beyond that ventromesial spine; thickened part of up- segment; upper flagellum reaching near- per flagellum falling slightly short of ros- ly to subterminal dorsal teeth ofrostrum. 仕al apex. Ambulatory pereiopods with carpi armed Antenna (Fig.2F) with scaphocerite with 1spine; dactyli with 2accessory 0.72-0.75 times as long as carapace，2. 76- claws on flexor margin. 2.92 times as long as wide，with disto- - Carapace (Fig. 2A) cov- lateral spine distinctly overreaching end ered with fine transverse striae ，armed of lamella; carpocerite slightly overreach- with 3teeth in midline posterior to ros- ing midlength of scaphocerite; basicerite tral articulation，anteriormost tooth larg- with rounded process directly dorsal to est，2 posterior teeth incompletely articu- ventrolateral spine. lated with carapace; supraorbital spine Mandible (Fig.3A )robust; palp 3-seg- absent; antennal spine directed anteri- mented，distal segment broad，rounded ， orly; pterγgostomi出 1 出 19le rounded. with numerous stiff setae; median seg- Rostrum (Fig. 2B) incompletely ar- ment slender，distally tapering，bearing ticulated with carapace，directed dorsally long setae distolaterally; incisor process in distal half，1. 39-1. 44 times as long as stout，truncate distally，bearing 8iπegu- carapace; dorsal margin armed with 2 lar blunt teeth; molar process obliquely basal and 2subterminal teeth; ventral truncate distally，with finely ridged cut- margin armed with 9or 10 teeth decreas- ting surface . ing in size distally; lateral carina arising First maxilla (Fig. 3B)with palp slen- 合omproximal two-fifths ofrostrum，lead- der，feebly bilobed distally，upper lobe 18 J.OKUNO &H .TACHlKAWA

Fig.1. Cinetorhynchus fasciatus new species. A ，holotype male (CBM-ZC 3629，6. 5mm CL )，合 esh specimen，lateral view (Photo by H. Tachikawa); B ，pa町 r叫 ype male (BPBM 811318，9.3mm CL )， alive in field (Photo by J. P. H ∞ver ).

with long setae distally，lower lobe with 出 lother row of dense short setae. long stout distal seta; proximal endite Second maxilla (Fig.3C )with palp rounded，with numerous stout setae on well developed，broadened basally; distal mesial margin and nearby ventral sur- endite bilobed，with dense long setae mar- face; distal endite truncate mesially， ginally，distal lobe broader and more bearing row of small movable spines and rounded than proximal lobe; proximal NEWSHRIMP OFCINETORHYNCHUS 19

E

B 占旦 L → c

F

C

245笥t立政 f; 完;22u; お? 説 ::32 狩r325間三日 222.112PJthA abdoJ!l il!_al somites; D ，telson ;E ，antennular peduncle; F，-antenna. Scales :A ， 15 mm; B，C ，F ，2 mm;D ，E ，1 mm . endite with sinuous mesial margin bear- proximal endite rounded; exopod well de- ing dense long setae; scaphognathite veloped，caridean lobe narrow，flagellum broad，posterior lobe elongate，tapering with dense long setae marginally; epipod posteriorly，marginally fringed with long large，rounded. setae，anterior lobe subquadrangular. Second maxilliped (Fig. 3E) with sub-

First maxilliped (Fig.3 D) with 3・seg- oval epipod;podobranch small but dis- mented palp，median segment longest， tinct; mesial margin of dactylus nearly distal segment very small; distal endite straight，with dense long setae; propodus with slightly concave distal margin， with distal margin broadly rounded，with 20 J.OKUNO &H. TACHlKAWA

，t ， 、 ， _- -D 、 ，

A

B

C トーー一一一叶 D

E

F ト一一一一- - - i

Fig. 3. Cineωrhynchu8 fasc臼tus new speci 伺. Para句pe male (BPBM 811318，9.3 mmCL). A ， mandible; B. 貧rstma豆11a; C ，se ∞ndma豆11a; D ，自 rst maxilliped，portions indicated by dotted lines were broken during 必館館“on;E，鴎∞ nd maxilliped; F，也仕 d maxilliped. Scales: A ，B， C ，E ， lmm;D，F，2mm.

sparse long setae; carpus wi也 feeble prcト times as long as carapace，1. 24-1. 43 trusion distolaterally; exopod with well- times as long as penultimate segment， developed flagellum bearing numerous terminallywi也6 -7 dark corneous spines; setae 叫ongdis旬1half. penultima旬 segment 0.29-0.32 times as Third maxilliped (Fig. 3F) reaching long as carapace; antepenultimate seg- level of distal third of scaphocerite; exo・ ment armed with dorsodistal and disto- pod relatively short; ultimate segment lateral spines. covered with dense short setae，0.4 0-0.4 2 Branchial form叫a as shown in Table 1. NEWSHRIMP OF CINETORHYNCHUS 21

Table 1. Branchial formula in Cinetorhynchus fasciαtus new species .

Maxillipeds Pereiopods I 11 III I 11 III IV V Pleurobranchs 1 1 一 1 I I Arthrobranchs 一 一2 1 l l Podobranchs 1 - - - Epipods 1 1 一1 1 Exopods 1 1 - - 1 1 一 一 一

First pereiopod (Fig，4A) chelate，mod- pace，2.00-2.25 times as long as carpus; erately robust，overreaching distal mar- carpus 0.25-0.31 times as long as cara- gin of antennal basicerite by length of pace; propodus 0.52-0.55 times as long as dactylus;chela 0.3 2-0.33 times as long as carapace，1. 75-2.08 times as long as car- C 訂 apace，1. 63-1. 91 times as long as car- pus. pus，fingers with darkly pigmented termi- Fi此h pereiopod generally similar to nal claw;carpus 0.17-0.20 times as long third and fourth pereiopods，reaching as carapace，distal margin straight， level of proximal fifth of scaphocerite; 仕inged with fine setae. merus armed with 3lateral spines，ven- Second pereiopod (Fig.4B) chelate， tral surface unarmed or armed with 1 slenderer than first pereiopod，reaching spine，0 .4 4-0.52 times as long as cara- level of proximal fourth of scaphocerite; pace，1. 68-1. 96 times as long as carpus; chela 0.28-0.29 times as long as carapace， carpus 0.23-0.29 times as long as cara- fingers with darkly pigmented terminal pace; propodus 0.4 9-0.53 times as long as claw; carpus 0.32-0.36 times as long as carapace，1. 68-2.27 times as long as car- carapace，1. 21-1. 67 times as long as pus. chela. Male first pleopod (Fi g. 4E) with endo- Third pereiopod (Fig. 4C) reaching pod rounded distally; appendix interna level of base of distolateral spine of well developed，broadened proximally， scaphocerite; ischium armed with 1ven- terminal margin with dense cincinnuli. tral spine，and with or without lateral Endopod ofmale second pleopod (Fig. 4F) spine; merus armed with 2-4 equidistant with appendices masculina and interna lateral spines and 2ventral spines，0.60- arising 仕ommidlength of mesial margin; 0.68 times as long as c訂 apace，2.07-2.39 appendix masculina oblong，slightly times as long as carpus; carpus armed shorter than appendix interna，distal with 1spine ，0 .28-0.30 times as long as margin 企inged with dense setae.Uropod carapace; propodus with mesial margin (Fig.4G) with protopod bearing acute pos- armed with sparse equidistant spinules， terolateral tooth; exopod broad，exceeding 0.52-0.54 times as long as carapace，1. 7ι tip of telson，lateral margin straight，with 1. 89 times as long as carpus; dactylus movable spine mesial to distolateral (Fi g.4D) armed with 2accessory claws. spine; endopod subequal in length to Fourth pereiopod generally similar to exopod. third pereopod，slightly overreaching Coloration. - Ground color of body midlength of scaphocerite; ischium armed pinkish.Carapace with red stripe run- with llateral and 1vental spine; merus ning across midlength of median carina， armed with 3-4 lateral and 1or 2ventral extending obliquely backward to each lat- spines，0.56-0.62 times as long as cara- eral side，preceded by oblique blotch of 22 J.OKUNO &H .TACHlKAWA

EF G n ト一一一一一→

Fig. 4. Cinetorhynchus fi αsci αtus new species. Holot)J>emale (CBM_:-ZC 6.5_ mm9LJ A ，firs! pereiopod; B ，second pereiopod; C，thiid pereiopod;D ，same ，dactylus; E，first pleopod; F，second pleopoa; G ，uropod. Scales: A-C，2 mm; D ベユ， 1mm.

S 出 ne color on lateral portion; bases of dor- terior band along posterior margin. Tel- sal teeth reddish. Rostrum with deep red son and uropods with 3transverse red band directly behind pinkish white apex. bands. Coxae and ischia of ambulatory Posterior m 訂 gins of first to fifth abdomi- pereiopods red; meri reddish distally， nal somites each with orange band bor- with distinct red band at distal fourth of dered by red lines; sixth somite pale or- length. ange，with 2transverse red bands，ante- Distribution. - Known from Chichi- rior band at midlength of somite and pos- jima Island，Ogasawara Islands and NEWSHRIMP OFCINETORHYNCHUS 23

Oahu，the Hawaiian Islands. fused when they 訂 e alive. However，they Ecological notes.- Resembling the are readily separated from each other in habitat of the congeners (Burkenroad， the armature of the carpi and dactyli of 1939; Okuno，1993 ，1994) ，the new species the ambulatory pereiopods as well as inhabits submarine caves in shallow relative length of the distolateral spine of rocky reefs. the scaphocerite. Etymology. - The specific name， Bruce (1984) 丑lu耐 ated acolor banded fα sci αtus ，reflects the banded coloration rhynchocinetid under the name of Rhyn- ofthe new species. chocinetes hiatti. The specimen also has Remarks. - Thearmature ofthe carpi the fif 油田ld sixth abdominal somites，tel- and dactyli of the ambulatory pereiopods son and uropods，all bright red，and cov- links the new species to C. hi αtti 企omthe ered with numerous white spots.Thi scol- Pacific and C .rigens 仕omthe Atlantic. oration does not fit 田 1y of the previously These three species are characterized by known rhynchocinetid species. Discovery the carpi of the third and fourth pereo- of such specimens would be desirable to pods armed with asingle lateral spine establish their systematic status. and the dactyli bearing two accessory claws on the flexor margins. From C. Key to species of Cinetorhynchus hiatti ，仕1e new species is differentiated by the rounded posteroventral angle of the 1. Second and third pereiopods without fourth abdominal pleuron，the stylocerite arthrobranch. (Dactyli of ambulatory not exceeding beyond the end of the an- pereiopods armed with 3accessory tennular distal segment，and the basi- claws pro垣mal to terminal claw) cerite 国首1ed with alateral spine. In addi- .C.m αnningi Okuno，1996 tion，distinct oblique bands on the poste- F10rida and Virgin Islands， rolateral p 訂 t ofthe c訂 apace and deeply western Atlantic orange ambulatory pereiopods，both ch訂・ - Second and third pereiopods with acteristic of C. hiatti (see Okuno，1995 ， arthrobranch …....・ H ・. . ..・ H ・-… H ・H ・...…・・ 2 1997)，訂e missing in C. fi. αsciatus. Cineto- rhynchus fasciαtus is distinguished 企om 2.Dactyli of ambulatory pereiopods arm- C .rigens by the following: apodobranch ed with 2accessory claws proximal to on the second maxilliped is distinct in C. terminal claw ....・ H ・. .・ H ・. . . ..・H ・..…H ・H ・.3 fasciαtus in stead of being vestigial as in - Dactyli of ambulatory pereiopods arm- C. rigens; meri of the third and fourth ed with 3accessory claws proximal to pereiopods each bear two旬 four sp也eson terminal claw .. ..・H ・-… ....・ H ・. . .. ・H ・. ..・ H ・.6 the lateral surface in C. fasciatus ，and five 3. Stylocerite far overreaching distal m 訂・ in C. rigens (see Okuno，1997) .Color pat- gin of antennular ultimate segment; tern is also useful to discriminate be- posteroventral angle offourth abdomi- tween the two species:many red spots on nal somite acutely pointed.(Color the carapace and abdominal somites are a feature of C .rigens (see Gordon，1936; banded) .….. .・H ・.....・ H ・.... ・H ・- …..C .hiatti (Hol血凶s &Hayashi ，1967) Wi吋z，1995). western and central Pacific Regarding the live coloration，the new species is generally similar to C. striatus ， - Stylocerite reaching or slightly over- paticularly in having broad brilliant red- reaching distal margin of antennular dish bands on the abdomen (Nomura & ultimate segment; posteroventral Hayashi，1992; Okuno，1995 ，1997) ，and angle of fourth abdominal somite therefore，their identification may be con- rounded ...・ H ・H ・H ・. . .. .・H ・. .... ・H ・..…. . . ・H ・.. 4 24 J.OKUNO &H. TACHlKAWA

4. Carpi of ambulatory pereiopods armed - Stylocerite falling short of distal mar- usually with 3spines. (Thickened part gin of antennular ultimate segment; of upper antennular flagellum falling distolateral spine of scaphocerite over- slightly short of series of dorsodistal reaching tip oflamella; fifth pereiopod rostral teeth; second maxilliped nearly falling short of midlength of scapho・

always with adeveloped podobranch; cerite. (Color marbled) ....・ H ・. .・ H ・H ・H ・.8

color marbled) ....・ H ・. . C. erythrostictus 8. Coxae offirst and third pereiopods with Okuno，1997 distinct corneous projections; carpi of southern Japan and New Caledonia third and fourth pereiopods armed - Carpi of 創 nb叫atory pereiopods armed usually with 2spines

usually with single spine ... .・ H ・... .・H ・..5 .C. hendersoni (Kemp，1925) Indo-central Pacific ，仕 omZanzibar 5. Second maxilliped usually with vestige to Austral Islands of podobranch; third 田 ld fourth pereio・ pods with meri armed usually with 5 - Coxae of first and third pereiopods spines on lateral surface. (Color without corneous projection; carpi of

marbled).... ・H ・- …. . . . ・ H ・. . .・ H ・- … C. rigens third and fourth pereiopods armed (Gordon，1936) usually with 3spines easterτ1 and western Atlantic .C. reticulαtus Okuno，1997

Indo ・central Pacific ，from Zanzibar - Second maxilliped with small but de・ 旬 Marqueseas Islands veloped podobranch; third and fourth pereiopods with meri armed with 2-4 spines on lateral surface. (Color Acknowledgments banded) '"・... C. fasciatus new species Wethank Mr. John P .Hoover who

6. Inner margin of antennular pro玄imal kindly provided us with the Hawaiian segment with 2-4 teeth ventrally; specimen，along with i旬 underwater pho- rostral ventral mar訴nwi也 distinct 也- tograph taken by himself. Our thanks go terval between ←5strong proximal 旬 Dr. Fenner A. Chace，Jr. ，for critically tee也 and ι. 9 small，equidistant distal reading an earlier draft of the manu- teeth. (Posteroventral angle of fourth script. abdominal somite acutely pointed) ... ・. . . C. concolor (Okuno，1994) Literature Cited western Pacific and 町 nor Sea Bruce，A. J. ，1984. : diverse and adaptable. In: F. Talbot (ed .)，Reader's Di- - Inner margin of antennular proximal gest Book of the Great Barrier Reef. segment with single tooth ventrally; Reader's Digest，Sydney ，19 8-211. rostral ventral margin with equidis- Burkenroad，M. D. ，1939 .Some remarks UDon tant teeth decreasing regularly in size non-peneid Crustacea Decapoda. The Annals and Magazine ofNatural History， distally... H H H H H ...7 ・・...... ・ ・. . . ..・ ・. . … ・・. ..・ series 11，3: 310-318. 7. Stylocerite reaching distal margin of Gordon， 1.， 1936. On the macruran genus antennular ultimate segment; disto- Rhynchocinetes，with the description of a lateral spine of scaphocerite falling new species .Proceedings of the Zoological Society of London，1936: 75-88. short oftip of lamella;afth pereiopod Holthuis，L. B.， 1995. Notes on Indo-Pacific overreaching midlength of scapho ・ Crustacea Decapoda III to IX. Zoologische Mededelingen，Leiden ，69: 139-151. cerite. (Color banded) ... .・ H ・. C. striαtus 一一ー一一" & Hayashi，K.・1.， 1967. Anew species (Nomura &Hayashi ，1992) of shrimp，Rhynchocinetes hiatti (Crusta- 回 u出ernJa凹 n，Philippin回 cea ，Decapoda). Annotationes Zoologicae and New Caledonia Japonenses，40(3) :161-170. NEWSHRIMP OF CINETORHYNCHUS 25

Kemp，S. ，1925. Notes on Crustacea Decapoda (In Japanese) in the Indian Museum XVII. Onvarious 一一一一， 1996. Cinetorhynchus manningi，a Caridea.Records of the Indian Museum， new shrimp (Crustacea:Decapoda :Ca 討- 27(4):249-343. dea: Rhynchocinetidae) 企omthe westem Nomura，K. & Hayashi，K.- 1.， 1992. Rhyncho- Atlantic. Proceedings ofthe Biological Soci- cinetes striatus，a new species (Decapoda， etyofW田 hin僻on，109(4): 72ι730. Caridea，Rhynchocinetidae) 企omsouthem 一一一， 1997. Review on the genus Cineto- Japan.Zo ological Science，9 (1): 199-206. rhynchus Holthuis，1995 from the Indo- Okuno，J. ，1993 .New record of ahinge-beak West Pacific (Caridea: Rhynchocinetidae). shrimp，Rhynchocinetes hendersoni from In B. Richer de Forges (ed.) ，Les Fonds eastem coast ofIzu Peninsula，Japan. Izu Meubles des Lagons de Nouvelle-Caledonie Oceanic Park Diving News，4 (3): ←5. (In (Sedimentologie，Benthos) .Etudes et The- Japanese) ses ，3. Paris，ORSRTOM ，31-58 ，1 p l. 一一一一 "1994. Rhynchocinetes concolor，a new Wirtz，P. ，1995. Unterwasserfuhrer Madeira， shrimp (Caridea: Rhynchocinetidae) from Kanaren，Az oren. Niedere Tiere. 247 pp. ， the Indo-West Pacific. Proceedings of the Delius Klasing，Stut 旬a此 Japanese Society of Systematic Zoology， (52): 65-74. 一一一一， 1995. Notes on three rhynchocinetid Address:Natural HistOIγMuseum and Insti- shrimps，Rhynchocinetes concolor Okuno， tute，Chiba ，955 ・2，Aoba-cho，Chuo ・ku， 1994，R .hiatti Holthuis et Hayashi，1967 Chiba 260 Japan. and R .striatus Nomura et Hayashi，1992 . E-mails:(JO)[email protected]; (HT) Izu Oceanic Park Diving News，6(8): 2-3. K90201邸 inet.ad.jp