Skip to main content Skip to main navigation menu Skip to site footer
Type: Article
Published: 2022-12-19
Page range: 133-144
Abstract views: 241
PDF downloaded: 44

Two new species of Xyalidae (Nematoda: Monhysterida) from intertidal zone of the Bohai Sea, China

College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China 2 Institute for Advanced Marine Research, China University of Geosciences, Guangzhou 511462, China
3 College of Life Sciences, Liaocheng University, Liaocheng 252059, China
College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China 2 Institute for Advanced Marine Research, China University of Geosciences, Guangzhou 511462, China
Nematoda Free-living marine nematodes taxonomy Paramonohystera gracilis sp. nov. Amphimonhystrella boucheri sp. nov.


Two new nematode species are described from the intertidal zone of the Bohai Sea, China. Paramonohystera gracilis sp. nov. is characterized by slender body with a long filiform tail; oval amphidial fovea 6 µm in diameter; spicules slender, 3.4 a.b.d. long; gubernaculum small, plate shaped without apophysis. It differs from the most similar species P. riemanni (Platt, 1973) Lorenzen, 1977 by much slender body and longer filiform tail. Amphimonhystrella boucheri sp. nov. is characterized by short body, deep buccal cavity with funnel shaped anterior portion, circular amphids, conico-cylindrical tail with two thirds conical anterior portion and a third cylindrical posterior portion, small spicules L-shaped and gubernaculum with short apophysis. It is distinguished from the most similar species A. unita Lorenzen, 1977 in buccal cavity funnel shaped, small amphidial fovea circular, spicules short with tapered distal end. Updated keys for valid species of Paramonohystera and Amphimonhystrella are provided.



  1. Boucher, G. (1971) Deux Espèces Nouvelles de Monhysterida (Nématodes) de la Vase Terrigène Cotière de Banyuls-Sur-Mer. Bulletin de la Société Zoologique de France, 96 (4), 557–562.
    Bresslau, E. & Schuurmans Stekhoven, J.H. (1940) Marine Freilebende Nematoda aus derNordsee. Musée royal d'Histoire naturelle de Belgique, Bruxelles, 74 pp.
    Chen, G. & Vincx, M. (2000) New and little known nematodes (Monhysterida, Nematoda) from the Strait of Magellan and Beagle Channel (Chile). Hydrobiologia, 429, 9–23.
    Chitwood, B.G. (1951) North American marine nematodes. Texas Journal of Science, 3, 627–672.
    Cobb, N.A. (1932) The english word “nema”. Journal of the American Medical Association, 98, 75.
    Fadeeva, N.P. & Belogurov, O.I. (1987) Structure of the Cephalic End of Nematodes of the Family Xyalidae and a Description of Three Species. The Soviet Journal of Marine Biology, 13 (1), 9–17.
    Filipjev, I.N. (1929) Classification of free-living Nematoda and relations to parasitic forms. Journal of Parasitology Urbana, 15, 281–282.
    Fonseca, G. & Bezerra, T.N. (2014) Order Monhysterida Filipjev, 1929. In: Schmidt-Rhaesa A. (ed.) Handbook of Zoology. Gastrotricha, Cycloneuralia and Gnatifera. Vol. 2. Nematoda. de Gruyter, Berlin, pp. 435–465.
    Gagarin, V.G. & Nguyen, T.T. (2008) Two new species of monhysterids (Nematoda, Monhysterida) from the Red River Delta (Vietnam). Zoologichesky Zhurnal, 87 (4), 505–510.
    Gagarin, V.G. & Thanh, N.V. (2009) Three new species of Monhysterids (Nematoda, Monhysterida) from a mangrove forest in the Mekong River Delta, Vietnam. Zoologichesky Zhurnal, 88 (10), 1170–1178.
    Gagarin, V.G. & Tu, N.D. (2021) Two New Species of the Order Monhysterida Filipjev, 1929 (Nematoda) from the Van Uc River Mouth in Vietnam. Inland Water Biology, 14 (5), 517–527.
    Geng, C.X., Hao Y.D. & Huang, Y. (2021) Description of Leptolaimus boucheri sp. nov. (Nematoda, Leptolaimidae) from the Bohai Sea, China. Journal of Natural History, 55, 2951–2960.
    Gerlach, S.A. & Riemann, F. (1973) The Bremerhaven Checklist of Aquatic Nematodes. A Catalogue of Nematoda Adenophorea Excluding the Dorylaimida. Veröffentlichungen des Instituts für Meeresforschung in Bremerhaven, 4, 1–404.
    Higgins, R.P. & Thiel, H. (1988) Introduction to the Study of Meiofauna. Smithsonian Institution Press, Washington, D.C., 488 pp.
    Hodda, M. (2022) Phylum Nematoda: a classification, catalogue and index of valid genera, with a census of valid species. Zootaxa, 5114 (1), 1–289.
    Huang, Y. & Sun, J. (2019) Paramonohystera weihaiensis sp. nov. (Xyalidae, Nematoda) from the intertidal beach of the Yellow Sea, China. Journal of Oceanology and Limnology, 37 (4), 1403–1408.
    Huang, Y. & Wu, X.Q. (2011) Two new free-living marine nematode species of the genus Vasostoma (Comesomatidae) from the China Sea. Cahiers de Biologie Marine, 52, 147–155.
    Inglis, W.G. (1983) An outline classification of the phylum Nematoda. Australian Journal of Zoology, 31, 243–255.
    Lorenzen, S. (1972) Die Nematodenfauna im Verklappungsgebiet für Industrieabwässer nordwestlich von Helgoland: I. Araeolaimida und Monhysterida. Zooligischer Anzeiger, 187 (3), 223–248.
    Lorenzen, S. (1973) Freilebende Meersenematoden aus dem Sublitoral der Nordsee und der Kieler Bucht. Veroffentlichungen des Instituts fur Meeresforschung in Bremerhaven, 14, 103–130.
    Lorenzen, S. (1977) Revision der Xyalidae (freilebende Nematoden) auf der Grundlage einer kritischen Analyse von 56 Arten aus Nord- und Ostsee. Veroffentlichungen des Instituts fur Meeresforschung in Bremerhaven, 16, 197–261.
    Lu, Y., Zhao, L.P. & Huang, Y. (2021) Descriptions of Deontolaimus holovachovi sp. nov. and Campylaimus zhoui sp. nov. from Chinese sea areas. Journal of the Marine Biological Association of the United Kingdom, 101, 265–270.
    McIntyre, A.D. & Warwick, R.M. (1984) Meiofauna techniques. In: Holme, N.A. & McIntyre, A.D. (Eds.), Methods for the study of marine benthos. Blackwell Scientific Publications, Oxford, pp. 217–244.
    Nemys (Eds.) (2022) Nemys: World Database of Nematodes. Available from: (accessed 1 July 2022)
    Platt, H.M. (1973) Freeliving marine nematodes from Strangford Lough, Northern Ireland. Cahiers de Biologie Marine, 14 (3), 295–321.
    Pastor de Ward, C.T. (1985) Nematodes de la Ria Deseado (Monhysteroidea, Xyalidae), Santa Cruz, Argentina II. Physis, Seccion A, 43 (105), 113–130.
    Schuurmans Stekhoven, J.H. (1935) Nematoda: Systematischer Teil, Nematoda errantia. In: Grimpe, G. & Wagler, E. (Eds.), Die Tierwelt der Nord- und Ostsee. Akademische Verlagsgesellschaft, Leipzig, pp. 1–173.
    Steiner, G. (1916). Freilebende Nematoden aus der Barentssee. Zoologische Jahrbücher, 39, 511–664.
    Timm, R.W. (1961) The marine nematodes of the Bay of Bengal. Proceedings of the Pakistan Academy Science, 1 (1), 25–88.
    Timm, R.W. (1963) Marine nematodes of the suborder Monhysterina from the Arabian Sea at Karachi. Proceedings of the Helminthological Society of Washington, 30 (1), 34–49.
    Tchesunov, A.V. & Miljutina, M.A. (2005) Three new minute nematode species of the superfamily Monhysteroidea from Arctic Abyss. Zootaxa, 1051 (1), 19-32.
    Venekey, V., Gheller, P.F., Maria, T.F., Brustolin, M.C., Kandratavicius, N., Vieira, D.C., Brito, S., Souza, G.S. & Fonseca, G. (2014) The state of the art of Xyalidae (Nematoda, Monhysterida) with reference to the Brazilian records. Marine Biodiversity, 2014, 1–24.
    Warwick, R.M., Platt, H.M. & Somerfied, P.J. (1998) Free-living marine nematodes part Ⅲ: Monhysterids. Synopses of the British Fauna No. 53. Field Studies council, Shrewsbury, 303 pp.
    Wieser, W. (1956) Free-living marine nematodes III. Axonolaimoidea and Mohysteroidea. Reports of the Lund University Chile Expedition 1948–49. Acta Universitatis Lundensis. Ny Följd. Andra Avdelningen, 52, 1–115.
    Yu, T.T. & Xu, K.D. (2015) Two new nematodes, Pseudelzalia longiseta gen. nov., sp. nov. and Paramonohystera sinica sp. nov. (Monhysterida: Xyalidae), from sediment in the East China Sea. Journal of Natural History, 49, 509–525.