Abstract
Morphological descriptions of three “walking nematode” species found for the first time in the White Sea are presented. Draconema ophicephalum (Claparède, 1863) (Draconematidae) and Epsilonema steineri Chitwood, 1935 (Epsilonematidae), both known from insufficient material and females only, are re-described and problems of their taxonomic identification as well as species compositions of respective genera are discussed. The new species Prochaetosoma marisalbi sp. n. (Draconematidae) differs from other Prochaetosoma species except P. longicapitatum (Allgén, 1935) in that the pharyngeal bulb lumen is not cuticularised, from P. longicapitatum by shape of body and rostrum, greater number of cephalic adhesive tubes, and from P. maertensi Decraemer, 1989 by having a relatively longer tail, fewer anterior adhesive tubes and longer spicules, besides lacking cuticular thickening in the pharyngeal bulb. Draconema hoonsooi, D. youngeouni, P.rochaetosoma beomseomense, P. brevicaudatum, P. byungilli, P. cracense, P. saheungi, P. sujungi, P. supseomense erected by Rho & Min (2011) are considered as invalid species while Prochaetosoma arcticum, P. lugubre and Epsilonema cygnoides are assumed as species inquirenda. From a phylogenetic tree based on the 18S rRNA gene, all three White Sea species adjoin to unidentified species of their respective genera.
References
Allen, M.W. & Noffsinger, E.M. (1978) A revision of the marine nematodes of the superfamily Draconematoidea Filipjev, 1918 (Nematoda: Draconematina). University of California, Publicatious in Zoology, 109, 133 pp.
Allgén, C. (1932) Weitere Beiträge zur Kenntnis der marinen Nematodenfauna der Campbellinsel. Nyt Magazin for Naturvidenskaberne, 70, 97–198.
Chitwood, B.G. (1935) Nomenclatorial notes I. Proceedings of the Helminthological Society of Washington, 2, 51–54.
Claparède, A.R.E. (1863) Beobachtungen über Anatomie und Entwicklungsgeschichte wirbellosen Tiere, an der Küste der Normandie angestellt. Leipzig (W. Engelmann), 120 pp.
Clasing, E. (1984) Interstitielle Fauna von Galapagos. XXXII. Epsilonematidae (Nematodes). Microfauna Marina, 1, 149–189.
Cobb, N.A. (1913) Draconema, a remarkable genus of marine freeliving nematodes nematodes. Journal of the Washington Academy of Sciences, 3, 145–149.
http://dx.doi.org/10.5962/bhl.part.20322Decraemer, W. (1982) Draconematidae and Epsilonematidae (Nematoda) from Laing Island Papua New Guinea, with one new genus and three new species. Bulletin del’Institut Royal des Sciences Naturelles de Belgique, Biologie, 54, 1–22, plates I–VIII.
Decraemer, W. (1989) Three new draconematid species from Papua New Guinea. Bulletin del’Institut Royal des Sciences Naturelles de Belgique, Biologie, 59, 5–24.
Decraemer, W. (1991) Revision of Epsilonema species from Antarctica described by Steiner (1931) (Nemata). Nematologica, 37, 20–37.
http://dx.doi.org/10.1163/187529291X00033Decraemer, W. & Gourbault, N. (1987) Marine nematodes from Guadeloupe and other Caribbean Islands. VII. The genus Epsilonema (Epsilonematidae). Bulletin de l’Institut Royal des Sciences Naturelles de Belgique, Biologie, 57, 57–77.
Decraemer, W., Gourbault, N. & Backeljau, T. (1997) Marine nematodes of the family Draconematidae (Nemata): a synthesis with phylogenetic relationships. Hydrobiologia, 357, 185–202.
http://dx.doi.org/10.1023/A:1003155424665De Ley, P. & Blaxter, M.L. (2004) A new system for Nematoda: combining morphological characters with molecular trees, and translating clades into ranks and taxa. Nematology Monographs and Perspectives, 2, 633–653.
Felsenstein, J. (1985) Phylogenies and the Comparative Method. The American Naturalist, 125, 1–15.
http://dx.doi.org/10.1086/284325Filipjev, I.N. (1918) Free-living marine nematodes of the Sevastopol area. Trudy Osoboi zoologicheskoi laboratorii Sevastopol’skoi biologicheskoi stantsii, 2 (4), 1–350 [in Russian]
Gad, G. (2006) Auf Stelzen laufende Nematoden ‒ die Draconematiden. Mikrokosmos, 95, 1‒11.
Garlitska, L., Neretina, T., Schepetov, D., Mugue, N., De Troch, M., Baguley, J. & Azovsky, A. (2012) Cryptic diversity of ʹcosmopolitanʹ harpacticoid copepod Nannopus palustris: genetic and morphological evidence species. Molecular Ecology, 21, 5336–5347.
http://dx.doi.org/10.1111/mec.12016Gerlach, S.A. (1952) Nematoden aus dem Küstengrundwasser. Akademie der Wissenschaften und Literatur, Mainz. Abhandlungen der mathemathik-naturwissenschaftlichen Klasse, 6, 315–372.
Gerlach, S.A. (1957) Die Nematodenfauna des Sandstrandes an der Küste von Mittelbrasilien (Brasilianische Meeres-Nematoden IV). Mitteilungen aus dem Zoologischen Museum in Berlin, 33, 411–459.
http://dx.doi.org/10.1002/mmnz.19570330206Gerlach, S.A. & Riemann, F. (1973) The Bremerhaven checklist of aquatic nematodes. A catalogue of Nematoda Adenophorea excluding the Dorylaimida. Part 1. Veröffentlichungen des Instituts für Meeresforschung in Bremerhaven, Supplement 4, 1–404.
Giribet, G., Carranza, S., Baguñá, J., Riutort, M. & Ribera, C. (1996) First molecular evidence for the existence of a Tardigrada + Arthropoda clade. Molecular Biology and Evolution, 13, 76-84.
http://dx.doi.org/10.1093/oxfordjournals.molbev.a025573Gourbault, N. & Decraemer, W. (1994) Two new species of Epsilonema from South Indopacific (Nemata, Epsilonematidae). Journal of Nematology, 26, 384–391.
Gourbault, N. & Decraemer, W. (1996) Marine nematodes of the family Epsilonematidae (Nemata): a synthesis with phylogenetic relationships. Nematologica, 42, 133–158.
http://dx.doi.org/10.1163/004325996X00011Hodda, M. (2007) Phylum Nematoda. Zootaxa, 1668, 265–293.
Holterman, M., Holovachov, O., van den Elsen, S., van Megen, H., Bongers, T., Bakker, J. & Helder, J. (2008) Small subunit ribosomal DNA-based phylogeny of basal Chromadoria (Nematoda) suggests that transitions from marine to terrestrial habitats (and vice versa) require relatively simple adaptations. Molecular Phylogenetics and Evolution, 48, 758–763.
http://dx.doi.org/10.1016/j.ympev.2008.04.033ICNZ (1999) International Code of Zoological Nomenclature (fourth edition). The Natural Museum, London.
Irwin-Smith, V.A. (1918) On the Chaetosomatidae, with descriptions of new species, and a new genus from the coast of New South Wales. Proceedings of the Linnean Society of New South Wales, 45, 757–814.
http://dx.doi.org/10.5962/bhl.part.4870Jensen, P. (1985) The nematode fauna in the sulphide-rich brine seep and adjacent bottoms of the East Flower Garden, NW Gulf of Mexico. I. Chromadorida. Zoologica Scripta, 14 (4), 247–263.
http://dx.doi.org/10.1111/j.1463-6409.1985.tb00195.xJohnston, T.H. (1938) A census of the free-living and plant-parasitic nematodes recorded as occurring in Australia. Transactions of the Royal Society of South Australia, 62, 149–167.
Karssen, G., Van Aelst, A.C. & De Deyn, G. (2000) Scanning electron microscopical observations on the coastal marine nematode Epsilonema pustulatum (Gerlach, 1952) Lorenzen, 1973 (Nematoda: Epsilonematidae). Nematology, 2, 685–693.
http://dx.doi.org/10.1163/156854100509547Kimura, M. (1980) A simple method for estimating evolutionary rate of base substitutions through comparative studies of nucleotide sequencers. Journal of Molecular Evolution, 16, 111–120.
http://dx.doi.org/10.1007/BF01731581Kito, K. (1976) Studies on the free-living marine nematodes from Hokkaido, I. Journal of the Faculty of Science, Hokkaido University, Series IV, Zoology, 20, 568–578.
Kito, K. (1979) Notes on the postembryonic development of Draconema japonicum Kito, 1976 (Nematoda: Draconematidae). Journal of the Faculty of Science, Hokkaido University, Series IV, Zoology, 22, 88–98.
Kito, K. & Chatterjee, T. (2012) New species of the genera Draconema Cobb, 1913 and Paradraconema Allen & Noffsinger, 1978 (Nematoda: Draconematidae) from Andaman Islands, Indian Oceans, with keys to species. Zootaxa, 3575, 78–88.
Kreis, H. (1963) Marine Nematoda. Zoology of Iceland, 2 (14), 1–68.
Leduc, D. & Zhao, Z. (2016) Phylogenetic relationships within the superfamily Desmodoroidea (Nematoda: Desmodorida), with descriptions of two new and one known species. Zoological Journal of the Linnean Society, 176, 511–536.
http://dx.doi.org/10.1111/zoj.12324Lorenzen, S. (1973) Die Familie Epsilonematidae (Nematodes). Mikrofauna Meeresboden, 25, 411–494.
Lorenzen, S. (1992) Epsilonematidae, marine nematodes, from a sandy salt marsh in France. Cahiers de Biologie Marine, 33, 441–446.
Lorenzen, S. (1994) Phylogenetic systematics of nematodes. The Ray Society, London, 254 pp.
Masalles, D. (1985) Dos nuevos Draconematidae (Nematoda) para el Mediterráneo español: Draconema claparedii (Metschnikoff, 1867) Filipjev, 1918, y Prochaetosoma vitielloi Allen & Noffsinger, 1978. Investigaciones Pesqueras, 49, 155‒164.
Metschnikoff, E. (1867) Beiträge zur Kenntnis der Würmer. I. Über Chaetosoma und Rhabdogaster. Zeitschrift für wissenschaftliche Zoologie, 17, 539–544.
Micoletzky, H. (1922) Die freilebenden Erdnematoden. Archiv für Naturgeschichte, 87A, 1–650.
Murphy, D. (1963) Three new species of marine nematodes from the Pacific near Depot Bay, Oregon. Proceedings of the Helminthological Society of Washington, 30, 249–256.
Raes, M., Decraemer, W. & Vanreusel, A. (2008) Walking with worms: coral-associated epifaunal nematodes. Journal of Biogeography, 35, 2207‒2222.
http://dx.doi.org/10.1111/j.1365-2699.2008.01945.xRaes, M., Vanreusel, A. & Decraemer, W. (2003) Epsilonematidae (Nematoda) from a cold-water coral environment in the Porcupine Seabight, with a discussion on the status Metaglochinema Gourbault & Decraemer, 1986. Hydrobiologia, 505, 49–72.
http://dx.doi.org/10.1023/B:HYDR.0000007245.66840.0aRho, H.S., Decraemer, W., Sørensen, M.V., Min, W.G., Jung, J. & Kim, W. (2011) Megadraconema cornutum, a new genus and species from Korea, with a discussion of its classification and relationships within the family Draconematidae (Nematoda, Desmodorida) based on morphological and molecular characters. Zoological Science, 28, 68–84.
http://dx.doi.org/10.2108/zsj.28.68Rho, H.S. & Min, W.G. (2011) Nematoda: Chromadorea: Desmodorida: Draconematidae. Marine dragon nematodes. Invertebrate Fauna of Korea, 13 (2). Incheon, Republic of Korea. 101 pp.
Rho, H.S., Min, W.G., Decraemer, W. & Kim, D.S. (2010) Prochaetosoma dokdoense sp. nov (Nematoda: Draconematidae) from Dokdo, Korea: First record of the genus Prochaetosoma from a shallow subtidal zone in the northwest Pacific Ocean. Marine Biology Research, 6, 172–188.
http://dx.doi.org/10.1080/17451000903078622Sapir, A., Dillman, A.R., Connon, S., Grupe, B., Mundo-Ocampo, M., Levin, L., Baldwin, J.G., Orphan, V.J. & Sternberg, P.W. (2014) Microsporidia-nematode associations in methane seeps reveal basal fungal parasitism in the deep sea. Front Microbiology, 5, 1–12.
http://dx.doi.org/10.3389/fmicb.2014.00043Schepotieff, A. (1908) Rhabdogaster cygnoides Metschn. (Untersuchungen über einige wenig bekannte freilebende Nematoden II.). Zoologische Jahrbücher (Abteilung für Systematik, Ökologie und Geographie der Tiere), 26, 393–400.
Seinhorst, J.W. (1959) A rapid method for the transfer of nematodes from fixative to anhydrous glycerin. Nematologica, 4, 67–69.
http://dx.doi.org/10.1163/187529259X00381Steiner, G. (1916) Freilebende Nematoden aus der Barentssee. Zoologische Jahrbücher (Abteilung für Systematik, Ökologie und Geographie der Tiere), 39, 511–676.
Steiner, G. (1927) Epsilonematidae, a new nemic family. Journal of Parasitology, 14, 65–66.
Steiner, G. (1931) Die Nematoden der deutschen Südpolar-Expedition 1901–03. I und II. Deutsche Südpolarexpedition 1901–03, 20, 167–216, 307–433.
Tamura, K., Stecher, G., Peterson, D., Filipski, A. & Kumar, S. (2013) MEGA 6: Molecular Evolutionary Genetyics Analysis version 6.0. Molecular Biology and Evolution, 30, 2725–2729.
http://dx.doi.org/10.1093/molbev/mst197Tchesunov, A. (2014) Order Desmodorida De Coninck 1965. In: Schmidt-Rhaesa, A. (Ed.), Handbook of Zoology. Gastrotricha, Cycloneuralia and Gnathifera. Volume 2: Nematoda. De Gruyter. Berlin/Boston, pp. 399–434.
Tchesunov, A.V. (2015) Free-living nematode species (Nematoda) dwelling in hydrothermal site of the North-Mid-Atlantic Ridge. Helgoland Marine Research, 69, 343–384.
http://dx.doi.org/10.1007/s10152-015-0443-6Venekey, V., Monteneiro Lage, L. & da Fonsêca-Genevois, V. (2005) Draconema brasiliensis and Draconema fluminensis (Chromadorida, Draconematidae): two new species of free living nematodes from a rocky shore affected by upwelling on Brazilian coast. Zootaxa, 1090, 51–64.
Verschelde, D. & Vincx, M. (1992) Freeliving marine nematodes from East African coasts. Bathyepsilonema anulosum sp. n. and Leptepsilonema richardi sp. n. Hydrobiologia, 239, 179–186.
http://dx.doi.org/10.1007/BF00007675Verschelde, D. & Vincx, M. (1994) Epsilonematidae (Nematoda: Desmodoroidea) from the East African coast, with a discussion on the external morphology of cuticular appendages. Nematologica, 40, 78–105.
http://dx.doi.org/10.1163/003525994X00067Whiting, M.F., Carpenter, J.C., Wheeler, Q.D. & Wheeler, W.C. (1997) The Strepsiptera problem: Phylogeny of the holometabolous insect orders inferred from 18S and 28S ribosomal DNA sequences and morphology. Systematic Biology, 46, 1–68.
http://dx.doi.org/10.1093/sysbio/46.1.1