Abstract
The ghost crab Ocypode mortoni George, 1982 was first described from the sandy shores of Sai Wan, Hong Kong, andalthough also identified from South China and Japan, has not been subsequently recorded in Hong Kong. The taxonomicstatus of O. mortoni is not clear as its original morphological description was not detailed, and there remains no informa-tion on its vertical and horizontal ecological distribution in Hong Kong. In the present study, O. mortoni was found to belocally rare in Hong Kong, only present at three of seven surveyed sites. It was always sympatric with the common O.ceratophthalmus (Pallas, 1772) at the same tidal level, and there appeared to be no clear habitat/niche distinction. Relativeabundance of O. mortoni vs. O. ceratophthalmus was at most 31%: 69% based on quantitative transect survey data fromSai Wan. Molecular phylogenetic analyses on 24 haplotypes (from 28 individuals) of 636-basepair (bp) mitochondrial cy-tochrome oxidase I (COI) gene of Ocypode spp. in East Asia show O. mortoni is a valid species most closely related to O.stimpsoni Ortmann, 1897, with an average difference of 37.64 bp, and nucleotide divergence of 6.25%. The two species are very similar morphologically, but adults of O. mortoni develop ocular stylets.References
Balss, H. (1922) Ostasiatische Decapoden. IV. Die Brachyrhynchen (Cancridea). Archiv für Naturgeschichte, 88, 94–166.
Barass, R. (1963) The burrows of Ocypode ceratophthalmus (Pallus) (Crustacea, Ocypodidae) on a tidal wave beach at Inhaca Island, Mozambique. The Journal of Animal Ecology, 32, 73–85.
Barnard, K.H. (1950) Descriptive catalogue of South African decapod Crustacea (crabs and shrimps). Annals of the South African Museum, 38, 1–837.
Chan, B.K.K., Chan, K.K.Y. & Leung, P.C.M. (2006) Burrow architecture of the ghost crab Ocypode ceratophthalma on a sandy shore in Hong Kong. Hydrobiologia, 560, 43–49.
Chan, B.K.K., Tsang, L.M. & Chu, K.H. (2007a) Morphological and genetic differentiation of the acorn barnacle Tetraclita squamosa (Crustacea, Cirripedia) in East Asia and description of a new species of Tetraclita. Zoologica Scripta, 36, 79–91.
Chan, B.K.K., Tsang, L.M., Ma, K.Y., Hsu, C.-H. & Chu, K.H. (2007b) Taxonomic revision of the acorn barnacles Tetraclita japonica and Tetraclita formosana (Crustacea: Cirripedia) in East Asia based on molecular and morphological analyses. Bulletin of Marine Science, 81, 101–113.
Cheung, C.-F. (2010) It was a pristine picture at Sai Wan, but not any more. South China Morning Post, 2010-07-16. [newspaper article]
Crosnier, A. (1965) Crustacés Décapodes Grapsidae et Ocypodidae. Faune de Madagascar, 18, 1–143.
Dahl, E. (1953) Some aspects of the ecology and zonation of the fauna of sandy beaches. Oikos, 4, 1–27.
Dai, A.-Y., 1991. Brachyura. In: Wei, C. & Chen, Y. (Eds), Fauna of Zhejiang. Zhejiang Science and technology Publishing House, Zhejiang, China, pp. 280–443. [in Chinese]
Dai, A.-Y., Song, Y.-Z & Yang, S.-L. (1985) A study on Ocypode from China. Acta Zootaxonomica Sinica, 10, 370–378. [in Chinese with English abstract]
Dai, A.-Y. & Yang, S.-L. (1991) Crabs of the China Seas. China Ocean Press, Beijing, 682 pp.
Dai, A., Yang, S., Song, Y. & Chen, G. (1986) Crabs of the China Seas. China Ocean Press, Beijing, 568 pp. [in Chinese with English abstract]
Davie, P. J. F., Shih, H.-T. & Chan, B.K.K. (2010) A new species of Mictyris (Decapoda, Brachyura, Mictyridae) from the Ryukyu Islands, Japan. In: Castro, P., Davie, P.J.F. Ng, P.K.L. & Richer de Forges, B. (Eds), Studies on Brachyura: a Homage to Danièle Guinot. Crustaceana Monographs, 11, 83–105.
Folmer, O., Black, M., Hoeh, W., Lutz, R. & Vrigenhoek, R. (1994) DNA primers for amplification of mitochondrial cytochrome c oxidase subunit I from diverse metazoan invertebrates. Molecular Marine Biology and Biotechnology, 3, 294–299.
Gee, N.G., 1926. Tentative list of Chinese Decapod Crustacea. Lingnaam Agricultural Review, 3, 156–166. [dated 1925]
George, R.W. (1982) The distribution and evolution of the ghost crabs (Ocypode spp.) of Hong Kong with a description of a new species. In: Morton, B.S. & Tseng, C.K. (Eds), Proceedings of the First International Marine Biological Workshop: The Marine Flora and Fauna of Hong Kong and Southern China. Hong Kong University Press, Hong Kong, pp. 185–194.
George, R.W. & Knott, M.E. (1965) The Ocypode ghost crabs of Western Australia. Journal of the Royal Society of Western Australia, 48, 15–21.
Guindon, S. & Gascuel, O. (2003) A simple, fast, and accurate algorithm to estimate large phylogenies by maximum likelihood. Systematic Biology, 52, 696–704.
Huang, J.-F., Yang, S.-L. & Ng, P.K.L. (1998) Notes on the taxonomy and distribution of the two closely related species of ghost crabs, Ocypode sinensis and O. cordimanus (Decapoda, Brachyura, Ocypodidae). Crustaceana, 71, 942–954.
Huang, J.-F. , Yu, H.-P. & Takeda, M. (1992) A review of the ocypodid and mictyrid crabs (Crustacea: Decapoda: Brachyura) in Taiwan. Bulletin of the Institute of Zoology, Academia Sinica, 31, 141–161.
Hughes, D.A. (1966) Behavioural and ecological investigations of the crab Ocypode ceratophthalmus (Crustacea: Ocypodidae). Journal of Zoology, London, 150, 129–143.
Kilburn, M. & Cheng, N.M. (2011) Hong Kong Headling Indicators for Biodiversity and Conversation- 2011 Report. Civic Exchange and Hong Kong Bird Watching Society, Hong Kong, 24 pp.
Kim, H.S. (1973) Anomura-Brachyura. In: Illustrated Encyclopedia of Fauna & Flora of Korea, 14. Samhwa, Seoul, pp. 589–682 [in Korean]
Kimura, M. (1980) A simple method for estimating evolutionary rates of base substitutions through comparative studies of nucleotide sequences. Journal of Molecular Evolution, 16, 111–120.
Morton, B. & Morton, J. (1983) The Sea Shore Ecology of Hong Kong. Hong Kong University Press, Hong Kong. 350 pp.
Ng, P.K.L., Guinot, D. & Davie, P.J.F. (2008) Systema Brachyurorum: Part I. An annotated checklist of the extant brachyuran crabs of the world. The Raffles Bulletin of Zoology Supplement, 17, 1–286.
Posada, D. (2008) jModelTest: Phylogenetic Model Averaging. Molecular Biology and Evolution, 25, 1253–1256.
Rambaut, A. & Drummond, A.J. (2009) Tracer v1.5. <http://beast.bio.ed.ac.uk/Tracer>.
Robertson, J.R. & William, P.J. (1981) Deposit-feeding by the ghost crab Ocypode quadrata (Fabricius). Journal of Experimental Marine Biology and Ecology, 56, 165–177.
Ronquist, F., Teslenko, M., van der Mark, P., Ayres, D.L., Darling, A., Höhna, S., Larget, B., Liu, L., Suchard, M. A. & Huelsenbeck, J.P. (2012) MRBAYES 3.2: efficient Bayesian phylogenetic inference and model choice across a large model space. Systematic Biology, 61, 539–542.
Ronquist, F., Huelsenbeck, J.P. & van der Mark, P. (2005) MrBayes 3.1 Manual. <http://mrbayes.csit.fsu.edu/manual.php>.
Sakai, K. (2000) On the occurrence of three species of crabs on Shikoku Island, Japan, and a new species, Pinnotheres taichungae nov. spec., from Taiwan (Decapoda, Brachyura). Crustaceana, 73, 1155–1162.
Sakai, T. (1939) Studies on the Crabs of Japan. IV. Brachygnatha, Brachyrhyncha. Yokendo, Tokyo, pp. 365–741.
Sakai, T. (1976) Crabs of Japan and the Adjacent Seas. Kodansha Ltd., Tokyo, 773 pp.
Shen, C.-J. (1932) The brachyuran Crustacea of North China. Zoologia Sinica, Series A, 9, 1–300.
Shen, C.-J. (1936) On a collection of brachyuran Decapoda from Hainan Island with descriptions of three new species. Chinese Journal of Zoology, 11, 63–80.
Shen, C.-J. (1940) The brachyuran fauna of Hong Kong. Hong Kong Fisheries Research Station Journal, 1, 211–242.
Shih, H.-T., Naruse, T. & Ng, P.K.L. (2010) Uca jocelynae sp. nov., a new species of fiddler crab (Crustacea: Brachyura: Ocypodidae) from the Western Pacific. Zootaxa, 2337, 47–62.
Shih, H.-T., Ng, P.K.L., Wong, K.J.H. & Chan, B.K.K. (2012) Gelasimus splendidus Stimpson, 1858 (Crustacea: Brachyura: Ocypodidae), a valid species of fiddler crab from the northern South China Sea and Taiwan Strait. Zootaxa, 3490, 30–47.
Shih, H.-T. & Suzuki, H. (2008) Taxonomy, phylogeny and biogeography of the endemic mudflat crab Helice/Chasmagnathus complex (Crustacea: Brachyura: Varunidae) from East Asia. Zoological Studies, 47, 114–125.
Smith, D.A.S. (1975) Polymorphism and selective predation in Donax faba Gmelin (Bivalvia: Tellinacea). Journal of Experimental Marine Biology and Ecology, 17, 205–219.
Stamatakis, A., Hoover, P. & Rougemont, J. (2008) A rapid bootstrap algorithm for the RAxML web-Servers. Systematic Biology, 75, 758–771.
Stimpson, W. (1858) Crustacea Ocypodoidea. Prodromus descriptionis animalium evertebratorum, quae in Expeditione ad Oceanum Pacificum Septentrionalem a Republica Federata missa, Cadwaladaro Ringgold et Johanne Rodgers ducibus, observavit et descripsit, Pars 5. Proceedings of the Academia of Natural Science, Philadelphia, 10, 93–110.
Stimpson, W. (1907) Report on the Crustacea (Brachyura and Anomura) collected by the North Pacific Exploring Expedition, 1853–1856. Smithsonian Miscellaneous Collections, 49, 1–240.
Tamura, K., Peterson, D., Peterson, N., Stecher, G., Nei, M. & Kumar, S. (2011) MEGA5: Molecular Evolutionary Genetics Analysis using Maximum Likelihood, Evolutionary Distance, and Maximum Parsimony Methods. Molecular Biology and Evolution, 28, 2731–2739.
Thompson, J.D., Higgins, D.G. & Gibson, T.J. (1994) CLUSTAL W: improving the sensitivity of progressive multiple sequence alignment through sequence weighting, position-specific gap penalties and weight matrix choice. Nucleic Acids Research, 22, 4673–4680.
Tweedie, M.W.F. (1937) On the crabs of the Family Ocypodidae in the collection of the Raffles Museum. Bulletin of Raffles Museum, 13, 104–170.
Tweedie, M.W.F. (1950) Notes on grapsoid crabs from the Raffles Museum. Bulletin of the Raffles Museum, 23, 310–324.
Weber, F. (1795) Nomenclator entomologicus secundum entomologiam systematicum ill. Fabricii, adjectis speciebus recens detectis et varietatibus. C.E. Bohn, Chilonii et Hamburg, 171 pp.
Wolcott, T.G. (1978) Ecological role of ghost crabs, Ocypode quadrata (Fabricius) on an ocean beach: scavengers or predators? Journal of Experimental Marine Biology and Ecology, 31, 67–82.
Wong, K.J.H., Chan, B.K.K. & Shih, H.-T. (2010) Taxonomy of the sand bubbler crabs Scopimera globosa De Haan, 1835, and S. tuberculata Stimpson, 1858 (Crustacea: Decapoda: Dotillidae) in East Asia, with description of a new species from the Ryukyus, Japan. Zootaxa, 2345, 43–59.