Okuno and Osawa Marine Biodiversity Records (2016) 9:28
DOI 10.1186/s41200-016-0026-5

MARINE RECORDOpen Access

Rediscovery of Chirostylus dolichopus
Ortmann, 1892 (Crustacea: Decapoda:Anomura: Chirostylidae) from its type
locality, Boso Peninsula, Japan, withdescription of the colouration in life
Junji Okuno1* and Masayuki Osawa2

Abstract
Background: The chirostylid squat lobster, Chirostylus dolichopus Ortmann, 1892, was rediscovered from its type
locality, Katsuyama (Boso Peninsula, Honshu, Japan) (35°06.7′N, 139°48.8′E), since the holotype had been collected in1880. The colouration in life of C. dolichopus is reported for the first time on the basis of a recently captured
topotypic specimen.
Results: Chirostylus dolichopus is characterized by the brilliant yellow ground colour and spot pattern on the meriof the ambulatory pereopods.
Conclusions: The colouration in life of C. dolichopus is diagnostic for species of Chirostylus. The examination of thepresent specimen revealed that C. dolichopus is distinguishable from other shallow water congeners, such as C.
ortmanni, C. sandyi, and C. stellaris, by the colouration as well as morphology.
Keywords: Crustacea, Chirostylidae, Chirostylus dolichopus, Topotypic specimen, Colouration, Japan

Background
Chirostylus Ortmann, 1892 is a small genus of the family
Chirostylidae and contains seven species, all from theIndo-West Pacific (Baba et al., 2008; Baba, 2009): C.
dolichopus Ortmann, 1892; C. micheleae Tirmizi &Khan, 1979; C. novaecaledoniae Baba, 1991; C. ortmanni
Miyake & Baba, 1968; C. rostratus Osawa & Nishikiori,
1998; C. sandyi Baba, 2009, and C. stellaris Osawa, 2007.
The type species of the genus, C. dolichopus, was originally described from Kadsiyama (= Katsuyama), Boso
Peninsula, Japan, and has hitherto been reported fromwide but scatterred localities in the Indo-West Pacific(cf. Baba et al., 2008). Prior to the present study, noadditonal specimens of the species have been recorded
from the type locality since the German biologist, Dr.
* Correspondence: okuno@chiba-muse.or.jp
1
Coastal Branch of Natural History Museum and Institute, 123 Yoshio,
Katsuura, Chiba 299-5242, Japan
Full list of author information is available at the end of the article

Ludwig H. P. Döderlein collected the holotype therein 1880. Moreover, the colouration in life is diagnostic for species of Chirostylus (see Baba, 2009), but
was not recorded for the holotype of C. dolichopus.
During a recent study on the shallow-water crustacean fauna of Boso Peninsula, we found the second
specimen referable to C. dolichipus from Katsuyama.
The present paper describes for the first time the colouration in life of C. dolichopus based on a topotypic
material. The possible identities of specimens fromother localities previously reported as C. dolichopus
were briefly discussed.

Methods
CL indicates specimen size, and is measured along thedorsal midline from the posterior margin of the orbit to
the posterior margin of the carapace. The specimen examined was collected with SCUBA equipment, and isdeposited in the collection of CMNH.

© 2016 Okuno and Osawa. Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0
International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, andreproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link tothe Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver(http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.

Okuno and Osawa Marine Biodiversity Records (2016) 9:28

Results
Taxonomic accountOrder Decapoda Latreille, 1802
Infraorder Anomura MacLeay, 1838
Family Chirostylidae Ortmann, 1892
Genus Chirostylus Ortmann, 1892
Chirostylus dolichopus Ortmann, 1892
Figs. 1 & 2Synonymy

Chirostylus dolichopus Ortmann, 1892: 246, figs. 2, 2b, c,e, i, o, z [type locality: Kadsiyama (= Katsuyama), Boso
Peninsula, Japan, shallow water]; Miyake, 1960: 97, pl.
48, fig. 8; Miyake & Baba, 1968: 381, figs. 1a, b, 2;
Takeda, 1982: 49, fig. 147; Baba, 2005: 16 (part, see discussion), fig. 2; Baba et al., 2008: 14 (part, see discussion;
not fig. 1A).
Material examined

CMNH-ZC 02495, 1 female (CL 5.5 mm), Uki-shima
Islet, Katsuyama, Kyonan, Boso Peninsula (east side ofTokyo Bay), Honshu, Japan, 35°06.7′N, 139°48.8′E,30 m, SCUBA, 14 July 2015, coll. J. Okuno.
Distinguishing characters

Rostral lobe rounded, unarmed (Fig. 1a). Gastric andcardiac regions unarmed. Branchial regions armed eachwith 1 spine near anterior extremity of each cervicalgroove (Fig. 1a). Third thoracic sternite with surface

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concave; anterior margin transverse, armed with 6 smallspines (Fig. 1b). Abdominal somites with smooth dorsal
surface. Ocular peduncle with feebly dilated cornea(Fig. 1a). Dactyli of second to fourth pereopods eachwith 6 (except for 7 in left fourth pereopod) corneous
spines on flexor margin, penultimate spine distinctly
stouter than ultimate spine (Fig. 1c).
Colouration

Ground colour of body and pereopods overall bright yellow (Fig. 2a, b). Dorsal surface of carapace (Fig. 2c) paleorange, with 3 main concentric U- to V-shaped markings:
outermost U-shaped, red with clear inner and outer margins, approximately following carapace outline; next whitewith narrow, clear margins, apex tightly rounded, approximately enclosing protogastric region; innermost whiteclear with red margins, acutely triangular, anterior apex
slightly exceeding cervical groove. Pterygostomian flap
with alternating white and orange-red longitudinal lines.
Abdominal tergites (Fig. 2c) transparent; anterior marginand midline each with orange line. Ocular peduncles eachwith thick red line dorsomesially. Cheliped (first pereopod) (Fig. 2a, b) with white and red longitudinal lines
dorsolaterally. Second to fourth pereopods (Fig. 2a, b)
each with red longitudinal line dorsally except for distal
part of propodus, this part brighter yellow than others; allmeri each with white and red spots (red spot larger) near
disto-extensor end, meri of both second pereopods andright fourth pereopod each with additional 1 or 2 redsmall spots on distal one third of extensor margin.

Fig. 1 Chirostylus dolichopus Ortmann, 1892, female (CL 5.5 mm), CMNH-ZC 02495: a carapace and ocular peduncles, dorsal view; b third thoracic
sternite, ventral view; c dactylus and distal part of propodus of right second pereopod, lateral view

Okuno and Osawa Marine Biodiversity Records (2016) 9:28

Page 3 of 4(see discussion). Known from the depths ranging 22 to
70 m (Miyake & Baba, 1968; present study).

Fig. 2 Chirostylus dolichopus Ortmann, 1892, female (CL 5.5 mm),
CMNH-ZC 02495: a entire specimen in situ, in association withalcyonarian soft coral at Uki-shima Islet, off Katsuyama, Boso
Peninsula, Japan, 30 m; b whole body of fresh specimen, dorsalview; c carapace, abdomen and cephalic appendages of fresh
specimen, dorsal view. Photographed by J. Okuno

Habitat

The present specimen was associated with an unidentified
alcyonarian octocoral attached to a small rock on thesandy slope at a depth of 30 m (Fig. 2a). The steep slope issituated at eastern margin of the Tokyo Submarine Canyon, and reaches about 200 m depth over narrow horizontal distance (about 3 km) (see Yano et al., 2007). At thediving sites around Uki-shima Islet, divers have observednine other individuals referable to C. dolichopus during
June to August of 2015, some living on colonies of fanlike gorgonaceans (Jiro Uochi, personal communication).
Distribution

Type locality: Kadsiyama (= Katsuyama), west coast of
Boso Peninsula (east side of Tokyo Bay), Honshu, Japan(Ortmann, 1892). Also known from Sagami Bay (Miyake& Baba, 1968). Other records of C. dolichopus from outside of Japan (cf. Baba et al., 2008) should be confirmedDiscussion
The present specimen agrees quite well with the previous descriptions of C. dolichopus by Ortmann (1892),
Miyake & Baba (1968) and Baba (2005) on account of
the distinguishing characters mentioned above. Baba(2005) re-examined the holotype of C. dolichopus andprovided illustrations of selected parts of the specimen.
Baba (2009) noted that the information on colourationof C. dolichopus is available from Miyake (1960, 1982)
and Takeda (1982). However, as indicated by Osawa(2007), the illustrated specimen in Miyake (1982) can be
identified as C. ortmanni on account of the characteristic colour pattern, especially the presence of blackwhite-black bands on the subterminal parts of the ambulatory meri. The illustrations of C. dolichopus by Miyake(1960) and Takeda (1982) are unfortunately inadequate
to determine the precise colouration and probably showa non-fresh specimen. Therefore, the detailed lifecolouration of C. dolichopus is reported here for the firsttime on the basis of the Japanese material.
Baba et al. (2008, Fig. 1a) showed a colour photographof a Philippine specimen identified as C. dolichopus.
However, the specimen differs from the present topotypic specimen in having the carmine-red chelipeds andambulatory legs, and in the absence of the subterminal
white and red spots on the ambulatory meri. The difference of colouration suggests that the specimen of Baba
et al. (2008) may not belong to the true C. dolichopus,
although re-examination of morphological characters of
the specimen is required.
Furthermore, the distributional range of the true C.
dolichopus is probably restricted in Japan and its adjacent waters in consideration of the known distributionsof three shallow water congeneric species. Chirostylus
ortmanni is distributed in the warm temperate waters ofJapan ranging from Boso Peninsula of Honshu mainland
to Satsuma Peninsula of southern Kyushu (including theIzu Islands), and northern part of Taiwan; C. sandyi has
been recorded only from the Philippines and Indonesia;and C. stellaris is known only from the Ryukyu Islands(Osawa, 2007; Baba, 2009; Lin & Osawa, 2014). Exceptfor Japanese waters, C. dolichopus has been previously
reported from Somali Republic, Mozambique Channeland Mauritious in the western Indian Ocean (Tirmizi &Khan, 1979; Baba, 2005), Western Australia and Northern
Territory in Australia (Haig, 1974; Ahyong & Baba, 2004)
and Sulu Archipelago in the Philippines (Baba, 1988); therecorded depths ranges were 35–238 m (Baba et al.,2008). Therefore, more detailed study is required for clarifing the systematic position of these specimens from outside of Japan.

Okuno and Osawa Marine Biodiversity Records (2016) 9:28

Ortmann (1892) described five species of squat lobsters
from Japan as new to science: two chirostylids, Chirostylus
dolichopus and Uroptychus japonicus Ortmann, 1892; onemunidid, Munida heteracantha Ortmann, 1892; and twomunidopsid, Munidopsis camelus (Ortmann, 1892) (asGalacantha A. Milne-Edwards, 1880) and M. taurulus
Ortmann, 1892. As mentioned above, the type locality ofC. dolichopus is Katsuyama of Boso Peninsula, Tokyo Bay.
Munida heteracantha was also originally described on thebasis of two specimens collected from Katsuyama andSagami Bay, but the type locality of the species is regarded
as Sagami Bay on account of the lectotype selection byMacpherson & Baba (1993). Thus, C. dolichopus is thesole squat lobster taxon which Ortmann (1892) originaly
described from Tokyo Bay.

Conclusions
The present paper describes for the first time the colouration in life of C. dolichopus based on a topotypic material.
Our examination on the topotypic specimen revealed that
C. dolichopus has a characteristic colouration in life, i. e.,
the brilliant yellow ground colour, the meri of the second
to fourth pereopods each with white and red spots on thedorsal subterminal part, and the absence of white small
spots through the entire length of the pereopods. Othershallow water congeners, such as C. ortmanni, C. sandyi,
and C. stellaris, have a reddish brown ground colour andwhite spots on the meri of ambulatory legs (see Osawa,2007; Baba, 2009).
Abbreviations
SCUBA: self-contained underwater breathing apparatus; CL: postorbital
carapace length; CMNH: Coastal Branch of Natural History Museum andInstitute Chiba.
Acknowledgements
We are indebted to Jiro Uochi (Kacchama Diving Survice), and Koichiro
Hirashima, Takahiro Hirashima and Yasuhiro Hirashima (Kyonan-KatsuyamaFishery Association), for their help in capturing the present specimen at Ukishima Islet, off Katsuyama, Boso Peninsula, Japan. Cordial thanks are extended to Shane T. Ahyong (Australian Museum, Sydney) for kindly reviewing
the manuscript and giving us valuable suggestions.
Authors’ contributions
JO collected the specimen, initinally identified it, and drafted the manuscript.
MO checked the identification of the specimen and helped to improve thefinal manuscript. All authors read and approved the final manuscript.
Authors’informationJO is a senior researcher and curator at CMNH. MO is a researcher at theResearch Center for Coastal Lagoon Environments of Shimane University.
Competing interests
The authors declare that they have no competing interests.
Author details
1Coastal Branch of Natural History Museum and Institute, 123 Yoshio,
Katsuura, Chiba 299-5242, Japan. 2Research Center for Coastal Lagoon
Environments, Shimane University, 1860 Nishikawatsu-cho, Matsue, Shimane
690-8504, Japan.

Page 4 of 4

Received: 16 April 2016 Accepted: 21 April 2016

References
Ahyong ST, Baba K. Chirostylidae from north-western Australia (Crustacea:Decapoda: Anomura). Mem Mus Victoria. 2004;61:57–64.
Baba K. Chirostylid and galatheid crustaceans (Decapoda: Anomura) of the “Albatross”
Philippine Expedition, 1907–1910. Res Crust. 1988;2(special number):1–203.
Baba K. Crustacea Decapoda: Chirostylus Ortmann, 1892, and Gastroptychus Caullery,1896 (Chirostylidae) from New Caledonia. In: Crosnier A, editor, Résultats desCampagnes MUSORSTOM, volume 9. Mém Mus Nat Hist Nat, Paris (A). 1991;
152: 463–477. Paris: Muséum National d'Histoire Naturelle, Paris.
Baba K. Deep-sea chirostylid and galatheid crustaceans (Decapoda: Anomura)from the Indo-Pacific, with a list of species. Galathea Rep. 2005;20:5–317.
Baba K. A new species of squat lobster (Decapoda, Anomura, Chirostylidae) fromthe Philippines and Indonesia. Crustaceana. 2009;82:795–802.
Baba K, Macpherson E, Poore GCB, Ahyong ST, Bermudez A, Cabezas P, Lin C-W,
Nizinski M, Rodrigues C, Schnabel KE. Catalogue of squat lobsters of theworld (Crustacea: Decapoda: Anomura—families Chilostylidae, Galatheidae
and Kiwaidae. Zootaxa. 2008;1905:1–220.
Haig J. The anomuran crabs of Western Australia: their distribution in the Indian
Ocean and adjacent seas. J Mar Biol Ass India. 1974;14:443–51.
Latreille PA. Histoire naturelle, générale et particulière des Crustacés et desInsectes. Ouvrage faissant suite à l'histoire naturelle générale et particulière,composée par Leclerc de Buffon, et rédigée par C.S. Sonnini, membre deplusieurs sociétés savantes. Paris: F. DuFart; 1802.
Lin CW, Osawa M. First record of the chirostylid squat lobster, Chirostylus
ortmanni Miyake & Baba, 1968 (Cructacea: Decapoda: Anomura), fromTaiwan. Platax. 2014;11:63–69.
MacLeay, WS. On the brachyurous decapod Crustacea brought from the Cape by
Dr. Smith. In: Smith A. editor, Illustrations of the Annulosa of South Africa;
being a portion of the objects of natural history chiefly collected during an
expedition into the interior of South Africa, under the direction of Dr.
Andrew Smith, in the years 1834, 1835. and 1836; fitted out by “The Cape ofGood Hope Association for Exploring Central Africa”. London: Smith, Elder,and Co; 1838. p. 53–71, 2 pls.
Macpherson E. Baba K. Crustacea Decapoda: Munida japonica Stimpson, 1858,
and related species (Galatheidae). In: Crosnier A, editor. Résultats desCampagnes MUSORSTOM, volume 10. Mém Mus Nat Hist Nat, Paris. Paris:Muséum National d'Histoire Naturelle, Paris. 1993;156:381–420.
Milne-Edwards A. Reports on the results of dredging under the supervision of
Alexander Agassiz, in the Gulf of Mexico and in the Caribbean Sea, etc. VIII.
Études préliminaires sur les Crustacés. Bull Mus Comp Zool Harvard Coll.
1880;8:1–168, pls 1–2.
Miyake S. Crustacea, Decapoda, Anomura. In: Okada Y, Uchida T, editors.
Encyclopedia Zoologica illustrated in colours, vol. IV. Tokyo: Hokuryukan;
1960. p. 88–97. pl. 44–48.
Miyake S. Japanese crustacean decapods and stomatopods in color: Vol. I,Macrura, Anomura and Stomatopoda. Osaka: Hoiku-sha; 1982.
Miyake S, Baba K. On the generic characters of Chirostylus, with description of two
Japanese species (Crustacea, Anomura). J Fac Agr, Kyushu Univ. 1968;14:379–87.
Ortmann A. Die Decapoden-Krebse des Strasburger Museums, mit besonder
Berücksichtigung der von Herrn Dr. Döderlein bei Japan und bei den Liu-KiuInslen gesammelten und zur Zeit im Strasburger Museum aufbewahrten
Foren. Die Abtheilungen Galatheidea und Paguridea. Zool Jahrb. Abtheil SystGeogr Biol Thiere. 1892;6:241–326. pls. 11–12.
Osawa M. A newspecies of Chirostylus Ortmann, 1892 (Crustacea: Decapoda: Anomura:Chirostylidae) from the Ryukyu Islands, southwestern Japan, with a supplemental
description of Chirostylus ortmanni Miyake & Baba, 1968. Zootaxa. 2007;1450:31–43.
Osawa M, Nishikiori K. A new species of the genus Chirostylus Ortmann, 1892
(Crustacea: Decapoda: Anomura: Chirostylidae) from the Ogasawara Islands,southern Japan. Proc Biol Soc Wash. 1998;111:382–388.
Takeda M. Keys to the Japanese and foreign crustaceans fully illustrated in colors.
Tokyo: Hokuryukan; 1982.
Tirmizi NM, Khan B. Two species of Chirostylus from the Indian Ocean withobservation on the generic characters (Decapoda, Chirostylidae).
Crustaceana. 1979;5(supplement):77–88.
Yano K, Miya M, Aizawa M, Noichi T. Some aspects of the biology of the goblin
shark, Mitsukurina owstoni, collected from the Tokyo Submarine Canyon andadjacent waters, Japan. Ichthyol Res. 2007;54:388–98.