Abstract
Ten species of fiddler crab are reported inhabiting the intertidal zone of a shore on Kaledupa Island, Indonesia. This is one of the highest recorded numbers of fiddler crab species living in sympatry, equating to over two-thirds of those known from the Wallacea biogeographic region and more than half of all those recorded from Indonesia. The descriptions to identify and distinguish these ten species are provided using a suite of characters e.g., carapace, major cheliped, male gonopods, gastric mills, life colouration in males and females, and notes on their ecology and distribution. Specimens were observed and collected in the Wakatobi National Park, near the village of Ambeua on Kaledupa island, Sulawesi Tenggara, Indonesia. Gastric mills are described for the first time for Gelasimus jocelynae, Paraleptuca crassipes, Tubuca coarctata, T. demani and T. dussumieri. A tabulation of anatomical features and colouration for all species in this study is provided as a support for field studies. It identifies features that support the recently proposed taxonomic revision of fiddler crabs by Shih et al. (2016).
References
Barnes, R.S.K. (2010) A remarkable case of fiddler crab, Uca spp., alpha diversity in Wallacea. Hydrobiologia, 637, 249–253. https://doi.org/10.1007/s10750-009-0007-3
Barnwell, F.H. & Thurman, C.L. (1984) Taxonomy and biogeography of the fiddler crabs (Ocypodidae: genus Uca) of the Atlantic and Gulf coasts of eastern North America. Zoological Journal of the Linnean Society, 81, 23–87. https://doi.org/10.1111/j.1096-3642.1984.tb02558.x
Beinlich, B. & von Hagen, H.O. (2006) Materials for a more stable subdivision of the genus Uca Leach. Zoologische Mededelingen, 80 (4), 9–32.
Bezerra, L.E.A., Dias, C.B., Santana, G.X. & Matthews-Cascon, H. (2006) Spatial distribution of fiddler crabs (genus Uca) in a tropical mangrove of northeast Brazil. Scientia Marina, 70 (4), 759–766. https://doi.org/10.3989/scimar.2006.70n4759
Bott, R. (1973) Die Typus-Art der Gattung Uca Leach 1814 (Decapoda: Ocypodidae). Senckenbergiana biologica, 54 (4–6), 311–314.
Crane, J. (1975) Fiddler Crabs of the World: Ocypodidae: Genus Uca. Princeton University Press, Princeton, New Jersey, 736 pp.
Clifton, J. (2010) Marine protected area networks in the Coral Triangle: implications for conservation and communities. In: Clifton, J., Unsworth, R.F.K. & Smith, D.J. (Eds.), Marine research & conservation in the Coral Triangle: the Wakatobi National Park. Nova Science Publishers Inc, New York, New York, pp. 224–236.
Detto, T., Backwell, P.R.Y., Hemmi, J.M. & Zeil, J. (2006) Visually mediated species and neighbour recognition in fiddler crabs (Uca mjoebergi and Uca capricornis). Proceedings of the Royal Society, 273B (1594), 1661–1666. https://doi.org/10.1098/rspb.2006.3503
Dyson, M.L., Perez, D.M., Curran, T., McCullough, E.L. & Backwell, P.R.Y. (2020) The role of claw color in species recognition and mate choice in a fiddler crab. Behavioral Ecology & Sociobiology, 74, 116. https://doi.org/10.1007/s00265-020-02899-w
Felgenhauer, B.E. & Abele, L.G. (1989) Evolution of the foregut in lower Decapoda. In: Felgenhauer, B.E., Waltung, L. & Thistle, A.B. (Eds.), Functional morphology of feeding and grooming in Crustacea. Crustacean Issues. AA Balkema, Rotterdam, pp. 205–219. https://doi.org/10.1201/9781003079354-13
Hopkins, M.J. & Thurman, C.L. (2010) The geographic structure of morphological variation in eight species of fiddler crabs (Ocypodidae: genus Uca) from the eastern United States and Mexico. Biological Journal of the Linnean Society, 100, 248–270. https://doi.org/10.1111/j.1095-8312.2010.01402.x
Kamanli, S.A., Kihara, T.C., Ball, A.D., Morritt, D. & Clark, P.F. (2017) A 3D imaging and visualisation workflow, using confocal microscopy and advanced image processing for brachyuran crab larvae. Journal of Microscopy, 266 (3), 307–323. https://dx.doi.org/10.1111/jmi.12540
Kihara, T.C. & Falavigna da Rocha, C.E. (2009) Técnicas para estudo taxonómico de copepodes harpacticoides da meiofauna marinha. Asterisco, Porto Alegre, 96 pp.
Klaus, A.V., Kulasekera, V.L. & Schawaroch, V. (2003) Three-dimensional visualization of insect morphology using confocal laser scanning microscopy. Journal of Microscopy, 212 (2), 107–121. https://doi.org/10.1046/j.1365-2818.2003.01235.x
Koch, V., Wolff, M. & Diele, K. (2005) Comparative population dynamics of four fiddler crabs (Ocypodidae, genus Uca) from a North Brazilian mangrove ecosystem. Marine Ecology Progress Series, 291, 177–188. https://doi.org/10.3354/meps291177
Lawson, T.J. & Grice, G.D. (1971) Use of the Scanning Electron Microscope in Morphological Studies of Copepods. Crustaceana, 21 (1), 111–112. https://doi.org/10.1163/156854071X00292
Levinton, J.S. & Mackie, J. (2013) Latitudinal diversity relationships of fiddler crabs: Biogeographic differences united by temperature. Global Ecology & Biogeography, 22, 1050–1059. https://doi.org/10.1111/geb.12064
López-Duarte, P.C., Christy, J.H. & Tankersley, R.A. (2011) A behavioral mechanism for dispersal in fiddler crab larvae (genus Uca) varies with adult habitat, not phylogeny. Limnology & Oceanography, 56, 1879–1892. https://doi.org/10.4319/lo.2011.56.5.1879
Macintosh, D.J. (1988) The ecology and physiology of decapods of mangrove swamps. In: Fincham, A.A. & Rainbow, P.S. (Eds.), Aspects of Decapod Crustacean Biology. Clarendon Press, Oxford, pp. 315–341.
Michels, J. (2007) Confocal laser scanning microscopy: using cuticular autofluorescence for high resolution morphological imaging in small crustaceans, Journal of Microscopy, 227, 1–7. https://doi.org/10.1111/j.1365-2818.2007.01787.x
Michie, L.A., Cragg, S.M., Barnes, R.S.K. & Bennett, W.A. (2015) Uca cryptica Naderloo, Türkay & Chen, 2010 (Crustacea: Brachyura: Ocypodidae) is no longer cryptic. Zootaxa, 3981 (2), 291–295. https://doi.org/10.11646/zootaxa.3981.2.10
Naderloo, R., Türkay, M. & Chen, H.-L. (2010) Taxonomic revision of the wide-front fiddler crabs of the Uca lactea group (Crustacea: Decapoda: Brachyura: Ocypodidae) in the Indo-West Pacific. Zootaxa, 2500 (1), 1–38. https://doi.org/10.11646/zootaxa.2500.1.1
Ng, P.K.L., Guinot D. & Davie P.J.F. (2008) Systema Brachyurorum: Part I. An annotated checklist of extant brachyuran crabs of the world. Raffles Bulletin of Zoology, Supplement: 17, 1–296
Rosenberg, M.S. (2014) Contextual cross-referencing of species names for fiddler crabs (genus Uca): An experiment in cyber-taxonomy. PLoS ONE, 9 (7), e101704. https://doi.org/10.1371/journal.pone.0101704
Rosenberg, M.S. (2020) A fresh look at the biodiversity lexicon for fiddler crabs (Decapoda: Brachyura: Ocypodidae). Part 2: Biogeography. Journal of Crustacean Biology, 40 (4), 1–20. https://doi.org/10.1093/jcbiol/ruaa029
Sakai, K., Türkay, M. & Yang, S.L. (2006) Revision of the Helice/Chasmagnathus complex (Crustacea: Decapoda: Brachyura). Abhandlungen der Senckenbergischen Naturforschenden Geselschaft, 565, 1–76.
Schuwerack, P-M.M., Barnes, R.S.K., Underwood, G.J.C. & Jones, P.W. (2006) Gender and species differences in sentinel crab (Macrophthalmus) feeding on an Indonesian mudflat. Journal of Crustacean Biology, 26, 119–123. https://doi.org/10.1651/C-2612.1
Serène, R. (1973) The names of the forms of Uca vocans (Linnaeus) (Decapoda, Ocypodidae), Crustaceana, 24 (3), 337–339. https://doi.org/10.1163/156854073X00722
Shih, H.-T., Kamrani, E., Davie, P.J.F. & Liu, M.Y. (2009) Genetic evidence for the recognition of two fiddler crabs, Uca iranica and U. albimana (Crustacea: Brachyura: Ocypodidae), from the northwestern Indian Ocean, with notes on the U. lactea species-complex. Hydrobiologia, 635, 373–382. https://doi.org/10.1007/s10750-009-9930-6
Shih, H.-T. (2012) Distribution of fiddler crabs in East Asia, with a note on the effect of the Kuroshio Current. Kuroshio Science, 6 (1), 83–89.
Shih, H.-T. (2015) Uca (Xeruca), a new subgenus for the Taiwanese fiddler crab Uca formosensis Rathbun, 1921 (Crustacea: Decapoda: Ocypodidae), based on morphological and molecular evidence. Zootaxa, 3974 (2), 151–169. https://doi.org/10.11646/zootaxa.3974.2.1
Shih, H.T., Ng, P.K.L., Davie, P.J.F., Schubart, C.D., Türkay, M., Naderloo, R., Jones, D.S. & Liu M.Y. (2016) Systematics of the family Ocypodidae Rafinesque, 1815 (Crustacea: Brachyura), based on phylogenetic relationships, with a reorganization of subfamily rankings and a review of the taxonomic status of Uca Leach, 1814, sensu lato and its subgenera. Raffles Bulletin of Zoology, 64, 139–175.
Shih, H.T., Ng, P.K.L., Ravichandran, S. & Prema, M. (2019) Resurrection of Gelasimus variegatus Heller, 1862, A Fiddler Crab Closely Related to Austruca bengali (Crane, 1975) and A. triangularis (A. Milne-Edwards, 1873) (Decapoda, Brachyura, Ocypodidae), from the Bay of Bengal, Indian Ocean. Zoological Studies, 58, e12. https://doi.org/10.6620/ZS.2019.58-12
Takeda, S. (2006) Behavioural evidence for body colour signaling in the fiddler crab Uca perplexa (Brachyiura: Ocypodidae). Journal of Experimental Marine Biology & Ecology, 330, 521–527. https://doi.org/10.1016/j.jembe.2005.09.021
Türkay, M. (1975) Statement: Die Bedeutung des Gonopodenaufbaus für die Aufklärung von Verwandtschaftsverhältnissen bei dekapoden Crustaceen. Aufsetzen und Reden senckenbergische naturforschung Geselschaft, 27, 114–115.
Weis, J.S. & Weis, P. (2004) Behavior of four species of fiddler crabs, genus Uca, in southeast Sulawesi, Indonesia. Hydrobiologia, 523 (1–3), 47–58. https://doi.org/10.1023/B:HYDR.0000033093.84155.1d