Skip to main content Skip to main navigation menu Skip to site footer
Published: 2016-03-24

Resurrection of Rhynchoplax Stimpson, 1858, with the description of two new species from Japan and Australia (Crustacea: Decapoda: Brachyura: Hymenosomatidae)

Natural History Museum and Institute, Chiba, 955-2 Aoba-cho, Chuo-ku, Chiba, 260-8682 Japan.
Museum Victoria, GPO Box 666, Melbourne, Vic. 3001, Australia.
Crustacea Halicarcinus new species resurrected genus taxonomy


Rhynchoplax Stimpson, 1858, is resurrected from synonymy with Halicarcinus White, 1846. Rhynchoplax hondai Takeda & Miyake, 1971, a species based on an immature female, is rediagnosed and two new species, R. magnetica n. sp. from northeastern Australia and R. minutula n. sp. from the Ryukyu Islands, Japan, are described. They differ from R. hondai in the shape of the rostrum, form of the subhepatic region and the armature of the pereopodal meri. All differ from the type species R. messor Stimpson, 1858, in having a longer and simple rostrum without supraocular pseudorostral spines and the absence of a postocular spine.



  1. Kemp, S. (1917) Notes on the Crustacea Decapoda in the Indian Museum. X. Hymenosomatidae. Records of the Indian Museum, 13, 243–279.

    Lucas, J.S. (1980) Spider crabs of the family Hymenosomatidae (Crustacea; Brachyura) with particular reference to Australian species: systematics and biology. Records of the Australian Museum, 33, 148–247.

    Ng, P.K.L., Chen, H.-L. & Fang, S.-H. (1999) On some species of Hymenosomatidae (Crustacea: Decapoda: Brachyura) from China, with description of a new species of Elamena and a key to the Chinese species. Journal of the Taiwan Museum, 52, 81–93.

    Ng, P.K.L. & Chuang, C.T.N. (1996) The Hymenosomatidae (Crustacea: Decapoda: Brachyura) of Southeast Asia, with notes on other species. The Raffles Bulletin of Zoology, Supplement, 3, 1–82.

    Ng, P.K.L. & Jeng, M.-S. (1999) The Hymenosomatidae (Decapoda, Brachyura) of Taiwan. Crustaceana, 72, 534–535. Avaliable from: (Accessed 21 Mar. 2016)

    Ng, P.K.L., Wang, C.-H., Ho, P.-H. & Shih, H.-T. (2001) An annotated checklist of brachyuran crabs from Taiwan (Crustacea: Decapoda). National Taiwan Museum Special Publication Series, 11, 1-86. Avaliable from: (Accessed 21 Mar. 2016)

    Poore, G.C.B., Guinot, D., Komai, T. & Naruse, T. (2016) Reappraisal of species attributed to Halicarcinus White, 1846 (Crustacea: Decapoda: Brachyura: Hymenosomatidae) with diagnosis of four new genera and one new species from New Ireland, Papua New Guinea. Zootaxa, 4093 (4), 480–514.

    Stimpson, W. (1858) Prodromus descriptionis animalium evertebratorum, quae in expeditione ad Oceanum Pacificum septentrionalem, a Republica Federata missa, Cadwaladaro Ringgold et Johanne Rodgers ducibus, observatis et descripsit. Pars V. Crustacea Ocypodoida. Proceedings of the Academy of Natural Science of Philadelphia, 10, 93–110. Avaliable from: (Accessed 21 Mar. 2016)

    Suzuki, H. (1985) A list of the macro-crustaceans collected from Formosa. Report on the Ocean Environment of the Southern Ryukyu Islands, 2, 49–59.

    Takeda, M. & Miyake, S. (1971) Two new hymenosomatid crabs of the genus Rhynchoplax from the West and South Pacific. Researches on Crustacea, 4/5, 164–172. Avaliable from: (Accessed 21 Mar. 2016)

    Sakai, T. (1976) Crabs of Japan and Adjacent Seas. Kodansha Ltd, Tokyo, 773 pp. (English text), 461 pp. (Japanese text) plus volume of 251 pls.