Abstract
Two new species of the gecarcinucid freshwater crab genus Arachnothelphusa are described from the Malaysian state of Sarawak in Borneo; one from Lanjak-Entimau Wildlife Sanctuary and another from Bako National Park. Arachnothelphusa rimba n. sp. is distinctive in possessing very long legs and a male first gonopod which has a cylindrical proximal part of the terminal segment, with the distal part sharply tapering to an acute tip. Arachnothelphusa bako n. sp. is superficially closest to A. kadamaiana from Sabah, but differs markedly by its narrower epistome, and proportionately shorter third maxillipeds and ambulatory legs.
References
Bott, R. (1969) Flußkrabben aus Asien und ihre Klassifikation (Crustacea, Decapoda). Senckenbergiana biologica, 50 (5–6), 359–366.
Bott, R. (1970) Die Süßwasserkrabben von Europa, Asien, Australien und ihre Stammesgeschichte. Eine Revision der Potamoidea und der Parathelphusoidea (Crustacea, Decapoda). Abhandlungen der Senckenbergischen naturforschenden Gesellschaft, 526, 1–338.
Borradaile, L.A. (1900) On a small collection of decapod crustaceans from freshwater in North Borneo. Proceedings of the Zoological Society of London, 1900, 93–95. https://doi.org/10.1111/j.1096-3642.1890.tb01706.x
Davie, P.J.F., Guinot, D. & Ng, P.K.L. (2015) Anatomy and functional morphology of Brachyura. In: Castro, P., Davie, P.J.F., Guinot, D., Schram, F.R. & Von Vaupel Klein, J.C. (Eds.), Treatise on Zoology—Anatomy, Taxonomy, Biology. The Crustacea, 9C-I, Decapoda: Brachyura (Part 1), pp. 11–163. https://doi.org/10.1163/9789004190832_004
Grinang, J. & Ng, P.K.L. (2014) Taxonomy of the freshwater crab Coccusa cristicervix Ng & Jongkar, 2004 (Decapoda: Brachyura: Gecarcinucidae), with description of a new species of Thelphusula from Sarawak, Malaysia, Borneo. Raffles Bulletin of Zoology, 62, 389–395.
Grinang, J. & Ng, P.K.L. (2015) The identity of the semiterrestrial crab Terrathelphusa kuchingensis (Nobili, 1901) (Crustacea: Decapoda: Brachyura: Gecarcinucidae), with descriptions of four new species from southwestern Sarawak, Borneo, Malaysia. Zootaxa, 3946 (3), 331–346. https://doi.org/10.11646/zootaxa.3946.3.2
Grinang, J. & Ng, P.K.L. (2021) A new species of the genus Arachnothelphusa Ng, 1991 (Crustacea: Decapoda: Gecarcinucidae) from a limestone cave in Sarawak (Malaysian Borneo). Raffles Bulletin of Zoology. Raffles Bulletin of Zoology, 69, 1–7.
Grinang, J., Pui, Y.M. & Ng, P.K.L. (2015) A new species of tree-hole dwelling crab of the genus Arachnothelphusa Ng, 1991 (Crustacea: Decapoda: Brachyura: Gecarcinucidae) from northern Sarawak, Malaysia, Borneo. Raffles Bulletin of Zoology, 63, 454–460.
Kumar, A.B., Raj, S. & Ng, P.K.L. (2017) Description of a new genus and new species of a completely arboreal crab (Decapoda: Brachyura: Gecarcinucidae) from the Western Ghats in India, with notes on the ecology of arboreal crabs. Journal of Crustacean Biology, 37 (2), 157–167. https://doi.org/10.1093/jcbiol/rux012
Li, J.-J., Rahayu, D.L. & Ng, P.K.L. (2018) Identity of the tree-spider crab, Parasesarma leptosoma (Hilgendorf, 1869) (Decapoda: Brachyura: Sesarmidae), with seven new species from the West Pacific. Zootaxa, 4482 (3), 451–490. https://doi.org/10.11646/zootaxa.4482.3.2
Maenosono, T. & Naruse, T. (2016) New records of two sesarmid crabs (Crustacea: Decapoda: Brachyura) from Ishigakijima Island, Ryukyu Archipelago, Japan. Fauna Ryukyuana, 28, 5–22.
Man, J.G. de (1887) Uebersicht der Indo-pacifischen Arten der Gattung Sesarma Say nebst einer Kritik der von W. Hess und E. Nauck in den Jahren 1865 und 1880 beschriebenen Decapoden. Zoologische Jahrbücher, Abtheilung für Systematik, Geographie und Biologie der Thiere, 2, 639–689, pl. 17.
Man, J.G. de (1899) Zoological Results of the Dutch Expedition to Central Borneo. The Crustacea. Part II, Brachyura. Notes Leyden Museum, 21, 53–144, pls. 5–12.
Martens, E. von (1868) Ueber einige ostasiatische Süsswasserthiere. Archiv für Naturgeschichte, 34 (1), 1–64, pl. 1. https://doi.org/10.5962/bhl.part.20475
Milne-Edwards, A. (1869) Révision du genre Thelphuse et description de quelques espèces nouvelles, faisant partie de la collection de Muséum. Nouvelles Archives du Muséum d’Histoire naturelle, Paris, 5, 161–191, pls. 8–11. https://doi.org/10.5962/bhl.title.10050
Mohamad Alwie, N.A.B. (2016) Diet of Labuanium politum (an obligate arboreal crab) at Kampung Tanjong Assam, Spaoh, Sarawak. Honours Dissertation, Faculty of Resource Science and Technology, Universiti Malaysia Sarawak, Kota Samarahan, 40 pp.
Naruse, T. & Ng, P.K.L. (2007) Scandarma splendidum, a new species of tree-climbing crab (Decapoda: Brachyura: Sesarmidae) from Sarawak, Malaysia, Borneo. Raffles Bulletin of Zoology, 55 (2), 337–341.
Naruse, T. & Ng, P.K.L. (2020) Revision of the sesarmid crab genera Labuanium Serène and Soh, 1970, Scandarma Schubart, Liu and Cuesta, 2003, and Namlacium SereÌne and Soh, 1970 (Crustacea: Decapoda: Brachyura: Sesarmidae), with descriptions of four new genera and two new species. Journal of Natural History, 54 (7–8), 445–532. https://doi.org/10.1080/00222933.2020.1763491
Ng, P.K.L. (1987) Freshwater crabs of the genus Isolapotamon Bott, 1968 from Sarawak, Borneo (Crustacea, Decapoda, Brachyura, Potamidae). Sarawak Museum Journal, New Series, 37 (58), 139–153, pls. 4–10.
Ng, P.K.L. (1988) The freshwater crabs of Peninsular Malaysia and Singapore. Department of Zoology, National University of Singapore, Shinglee Press, Singapore, viii + 156 pp., 63 figs, 4 colour pls.
Ng, P.K.L. (1991) Bornean freshwater crabs of the genus Arachnothelphusa gen. nov. (Crustacea: Decapoda: Brachyura: Gecarcinucidae). Zoologische Mededelingen, 65 (1), 1–12.
Ng, P.K.L. (1995a) The freshwater crabs and prawns (Crustacea: Decapoda) of Bako National Park, Sarawak, Malaysia, with descriptions of one new genus and three new species. Raffles Bulletin of Zoology, 43 (1), 181–205.
Ng, P.K.L. (1995b) On one new genus and three new species of freshwater crabs (Crustacea: Decapoda: Brachyura: Potamidae and Grapsidae) from Lanjak‑Entimau, Sarawak, East Malaysia, Borneo. Zoologische Mededelingen, 69 (5), 57–72.
Ng, P.K.L. (2004) Crustacea: Decapoda, Brachyura. In: Freshwater Invertebrates of the Malaysian Region. In: Yule, C. & Yong, H.S. (Eds.), Malaysian Academy of Sciences, pp. 311–336.
Ng, P.K.L. (2013) A new species of Scandarma (Crustacea: Brachyura: Sesarmidae) from Sabah, Borneo, Malaysia. Zootaxa, 3652 (2), 289–294. https://doi.org/10.11646/zootaxa.3652.2.6
Ng, P.K.L. (2015) Semiterrestrial crabs of the genus Geosesarma De Man, 1892 (Crustacea, Brachyura, Sesarmidae) from western Borneo, Indonesia, with descriptions of three new species. Zootaxa, 4048 (1), 37–56. https://doi.org/10.11646/zootaxa.4048.1.2
Ng, P.K.L. & Goh, R. (1987) Cavernicolous freshwater crabs (Crustacea Decapoda, Brachyura) from Sabah, Borneo. Stygologia, 3 (4), 313–330, pls. 1–3.
Ng, P.K.L. & Grinang, J. (2004) Decapod crustaceans with descriptions of three new species. In: Yong, H.S., Ng, F.S.P. & Yen, E.E.L. (Eds.), Sarawak Bau Limestone Biodiversity, Sarawak Museum Journal, New Series, 59 (Special Issue No. 6), 299–325.
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, 1–286.
Ng, P.K.L., Lee, B.Y. & Tan, H.H. (2015) Observations on the taxonomy and ecology of Labuanium politum (De Man, 1887) (Crustacea: Decapoda: Sesarmidae), an obligate arboreal crab on the nipah palm, Nypa fructicans (Arecales: Arecaceae). Raffles Bulletin of Zoology, Supplement 31, 216–225.
Ng, P.K.L. & Ng, P.Y.C. (2018) The freshwater crabs of Danum Valley Conservation Area in Sabah, East Malaysia, with a description of a new species of Thelphusula Bott, 1969 (Crustacea, Brachyura, Gecarcinucidae, Potamidae, Sesarmidae). Zookeys, 760, 89–112. https://doi.org/10.3897/zookeys.760.24787
Nobili, G. (1901) Note intorno ad una collezione Crostacei di Sarawak (Borneo). Bollettino dei Musei di Zoologia ed Anatomia comparata della Regia, Università di Torino, 16 (397), 1–14, figs. A, B. https://doi.org/10.5962/bhl.part.7275
Rahim, S.A.K.A., Masini, A.I. & Mohamad Alwie, N.A. (2020) Size at sexual maturity of Nipa-obligate crab Labuanium politum (Crustacea: Sesarmidae); harvesting plan preceding commercialisation. Journal of Sustainability Science and Management, 15 (5), 10–18. https://doi.org/10.46754/jssm.2020.07.003
Rathbun, M.J. (1904) Les crabes d’eau douce (Potamonidae). Nouvelles Archives du Muséum d’Historie naturelle, Series 4, 6, 225–312.
Schubart, C.D., Liu, H.-C. & Ng, P.K.L. (2009) Revision of Selatium Serène & Soh, 1970 (Crustacea: Brachyura: Sesarmidae), with description of a new genus and two new species. Zootaxa, 2154 (1), 1–29. https://doi.org/10.11646/zootaxa.2154.1.1
Schubart, C.D. & Ng, P.K.L. (2020) Revision of the heterogeneous sesarmid genera Chiromantes Gistel, 1848, and Pseudosesarma Serène & Soh, 1970 (Crustacea: Brachyura: Thoracotremata), using morphology and molecular phylogenetics, with the establishment of nine new genera and two new species. Raffles Bulletin of Zoology. [in press]
Targioni-Tozzetti, A. (1877) Crostacei Brachyuri e Anomuri. Zoologia del viaggio intorno al Globo della R. Pirocorvetta Magenta durante gli anni 1865–1868. Pubblicazioni del R. Istituto di Studi superiori pratici e di Perfezionamento in Firenze, Sezione di Scienze fisiche e naturali, Successori le Monnier, Firenze, 1, i–xxix + 1–257, pls. 1–12.
Tweedie, M.W.F. (1950) Grapsoid crabs from Labuan and Sarawak. Sarawak Museum Journal, 5 (2), 338–369.