Skip to main content Skip to main navigation menu Skip to site footer
Type: Articles
Published: 2005-02-01
Page range: 1–46
Abstract views: 1099
PDF downloaded: 18

Tardigrade taxonomy: an updated check list of the taxa and a list of characters for their identification

Department of Animal Biology, University of Modena and Reggio Emilia, Modena, via Campi 213/d, 41100, Modena, Italy
Department of Animal Biology, University of Modena and Reggio Emilia, Modena, via Campi 213/d, 41100, Modena, Italy
Tardigrada systematics check list taxonomic criteria

Abstract

Since the most recent monograph on Tardigrada by Ramazzotti & Maucci (1983), many changes have been introduced in the systematics of this phylum which has gone through different revisions and has been expanded by several new taxa. Moreover, the number of species is considerably increased (almost doubled to more than 960 species) and new families and genera have been created, while many taxa have been amended. The difficulty in finding a complete, updated list of taxa and the problems with putting together all the newly proposed taxonomic criteria, led us to compile an updated list of tardigrade taxa. This list is supplemented by a series of bibliographic references inherent in the synonymies and/or the amended diagnosis of the taxa occurred after 1983, and a list of the main characters used in the diagnosis of the species. These lists are aimed at helping not only the specialists studying this group, but also researchers interested in biodiversity and those who have to refer to this animal group.

References

  1. Abe, W., Ito, M. & Takeda, M. (2000) First record of Echiniscus hoonsooi (Tardigrada: Echiniscidae) from Japan. Species Diversity, 5, 103–110.

    Aguinaldo, A.M.A., Turbeville, J.M., Linford, L.S., Rivera, M.C., Garey, J.R., Raff, R.A. & Lake, S.A. (1997) Evidence for a clade of nematodes, arthropods and other moulting animals. Nature, 387, 489–493.

    Bello, G. & de Zio Grimaldi, S. (1998) Phylogeny of the genera of the Stygarctidae and related families (Tardigrada: Heterotardigrada). Zoologischer Anzeiger, 237, 171–183.

    Bertolani, R. (1981) The taxonomic position of some eutardigrades. Bollettino di Zoologia, 48, 197–203.

    Bertolani, R. (2003) Thulinius, new generic name substituting for Thulinia Bertolani, 1981 (Tardigrada, Eutardigrada). Zootaxa, 314, 1–4.

    Bertolani, R. & Biserov, V.I. (1996) Leg and claw adaptations in soil tardigrades, with erection of two new genera of Eutardigrada, Macrobiotidae: Pseudohexapodibius and Xerobiotus. Invertebrate Biology, 115, 299–304.

    Bertolani, R. & Grimaldi, D. (2000) A new eutardigrade (Tardigrada: Milnesiidae) in amber from the Upper Cretaceous (Turonian) of New Jersey. In: D. Grimaldi (Ed.), Studies on fossils in amber, with particular reference to the Cretaceous of New Jersey, Backhuys Publishers, Leiden The Netherland, pp. 104–109.

    Bertolani, R. & Kristensen, R.M. (1987) New records of Eohypsibius nadjae Kristensen, 1982, and revision of the taxonomic position of two genera of Eutardigrada (Tardigrada). In: R. Bertolani (Ed.), Biology of Tardigrades, Sel. Symp. Monogr. U.Z.I., Vol. 1, Mucchi, Modena, pp. 359–372.

    Bertolani, R. & Rebecchi, L. (1993) A revision of the Macrobiotus hufelandi group (Tardigrada, Macrobiotidae), with some observations on the taxonomic characters of eutardigrades. Zoologica Scripta, 22, 127–152.

    Bertolani, R., Rebecchi, L. & Claxton, S.K. (1996) Phylogenetic significance of egg shell variation in tardigrades. Zoological Journal of the Linnean Society, 116, 139–148.

    Bertolani, R., Marley, N. & Nelson, D.R. (1999) Re-description of the genus Thulinia (Eutardigrada: Hypsibiidae) and of Thulinia augusti (Murray, 1907) comb. n. Zoologischer Anzeiger, 238, 139–146.

    Binda, M.G. (1988) Ridescrizione di Macrobiotus echinogenitus Richters, 1904 e sul valore di buona specie di Macrobiotus crenulatus Richters, 1904 (Eutardigrada). Animalia, 15, 201–210.

    Binda, M.G. & Kristensen, R.M. (1986) Notes on the genus Oreella (Orellidae) and the systematic position of Carphania fluvialis Binda, 1978 (Carphanidae fam. nov., Heterotardigrada). Animalia, 13, 9–20.

    Binda, M.G. & Pilato, G. (1992) Minibiotus furcatus, nuova posizione sistematica per Macrobiotus furcatus Ehrenberg, 1859, e descrizione di due nuove specie (Eutardigradi). Animalia, 19, 111–120.

    Binda, M.G. & Pilato, G. (1993) Ridescrizione di Echiniscus reticulatus Murray, 1905 e descrizione di Echiniscus cirinoi, nuova specie di tardigrado della Tanzania. Animalia, 20, 55–58.

    Biserov, V.I. (1990a) On the revision of the genus Macrobiotus. The subgenus Macrobiotus s. str.: a new systematic status of the hufelandi group (Tardigrada, Macrobiotidae). Communication 1. Zoologicheskii Zhurnal, 69, 5–17. (in Russian).

    Biserov, V.I. (1990b) On the revision of the Macrobiotus genus. The subgenus Macrobiotus s. str.: a new taxonomic status of the hufelandi group (Tardigrada, Macrobiotidae). Communication 2. Zoologicheskii Zhurnal, 69, 38–50. (in Russian).

    Biserov, V.I. (1996) Tardigrades of the Taimyr peninsula with descriptions of two new species. Zoological Journal of Linnean Society, 116, 215–237.

    Boesgaard, T.M. & Kristensen, R. M. (2001) Tardigrades from Australian marine caves. With a redescription of Actinarctus neretinus (Arthrotardigrada). Zoologischer Anzeiger, 240, 253–264.

    Brusca, R.C. & Brusca, G.J. (2003) Invertebrates. Sinauer, Sunderland MA.

    Bussau, C. (1992) New deep-sea Tardigrada (Arthrotardigrada, Halechiniscidae) from a manganese nodule area of the eastern South Pacific. Zoologica Scripta, 21, 79–91.

    Claxton, S.K. (1998) A revision of the genus Minibiotus (Tardigrada: Macrobiotidae) with descriptions of eleven new species from Australia. Records of the Australian Museum, 50, 125–160.

    Claxton, S.K. (1999) Milnesioides exsertum gen. n. sp. n., a new tardigrade from Australia (Tardigrada: Milnesiidae). Zoologischer Anzeiger, 238, 183–190.

    Claxton, S.K. (2001) Antechiniscus in Australia: description of Antechiniscus moscali sp. n. and redescription of Anthechiniscus parvisentus (Horning & Schuster, 1983) (Heterotardigrada: Echiniscidae). Zoologischer Anzeiger, 240, 281–289.

    Cooper, K.W. (1964) The first fossil tardigrade: Beorn leggi Cooper, from cretaceous amber. Psyche, 71, 41–48.

    D’Addabbo Gallo, M., Grimaldi de Zio, S. & Morone De Lucia, M.R. (1986) Description of two species of Halechiniscidae belonging to the sub-family Halechiniscinae and Styraconyxinae (Tardigrada: Heterotardigrada). Oebalia, XIII, 69–75.

    D'Addabbo Gallo, M., Pietanza, R., D’Addabbo, R., Morone De Lucia, M.R. & Grimaldi de Zio, S. (1999) A redescription of Actinarctus doryphorus (Tardigrada, Heterotardigrada). Cahiers de Biologie Marine, 40, 21–27.

    D’Addabbo Gallo, R., D’Addabbo, M., & Grimaldi de Zio, S. (2000) Redescription of Batillipes dicrocercus Pollock, 1970 and revision of the genus Batillipes (Tardigrada, Heterotardigrada). Zoologischer Anzeiger, 239, 329–339.

    Dastych, H. (1973) Systematic studies on Tardigrada, II. Echiniscus clavisetosus MihelÖiÖ 1958, a synonym of Echiniscus spitzbergensis Scourfield 1897. Bulletin de la Société des amis des sciences et des lettres de Pozna¡, 14, 89–99.

    Dastych, H. (1985) West Spitsbergen Tardigrada. Acta Zoologica Cracoviensia, 28, 169–214.

    Dastych, H. (1990) Isohypsibius sattleri (Richters 1902), a valid species (Tardigrada). Senckenbergiana biologica, 71, 181–189.

    Dastych, H. (1991) Redescription of Hypsibius antarcticus (Richters, 1904), with some notes on Hypsibius arcticus (Murray, 1907) (Tardigrada). Mitteilungen aus dem Hamburgischen Zoologischen Museum und Institut, 88, 141–159.

    Dastych, H. (1993) Redescription of the cryoconical tardigrade Hypsibius klebelsbergi MihelÖiÖ, 1959, with notes on the microslide collection of the late Dr. F. MihelÖiÖ (Tardigrada). Sonderdruck aus Veröffentlichungen des Museum Ferdinandeum, 73, 5–12.

    Dastych, H. (1997) Redescription of Isohypsibius sculptus Ramazzotti, 1962 (Tardigrada). Entomologische Mitteilungen aus dem Zoologischen Museum Hamburg, 12, 163–167.

    Dastych, H. (1998) Description of eggs in the Antarctic tardigrade Minibiotus stuckenbergi (Dastych et al., 1990) (Tardigrada, Macrobiotidae). Entomologische Mitteilungen aus dem Zoologischen Museum Hamburg, 12, 289–294.

    Dastych, H. (1999) Redescription of the Sub-Antarctic tardigrade Mopsechiniscus imberbis (Richters, 1908) (Tardigrada). Mitteilungen aus dem Hamburgischen Zoologischen Museum und Institut, 96, 21–35.

    Dastych, H. (2000) Redescription of the neotropical tardigrade Mopsechiniscus granulosus MihelÖiÖ, 1967 (Tardigrada). Mitteilungen aus dem Hamburgischen Zoologischen Museum und Institut, 97, 45–57.

    Dastych, H. (2001) Note on the revision of the genus Mopsechiniscus (Tardigrada). Zoologischer Anzeiger, 240, 299–308.

    Dastych, H. (2002) The tardigrade Hebesuncus conjungens (Thulin, 1911) in the Alps, with notes on morphology and distribution (Tardigrada). Entomologische Mitteilungen aus dem Zoologischen Museum Hamburg, 14, 83–94.

    Dastych, H. (2002/2003) Diphascon langhovdense (Sudzuki, 1964) stat. nov., a new taxonomic status for the semi-terrestrial tardigrade (Tardigrada). Acta Biologica Benrodis, 12, 19–25.

    Dastych, H. (2003) Redescription and notes on the biology of the glacier tardigrade Hypsibius klebelsbergi MihelÖiÖ, 1959 (Tardigrada), based on material from the Ötztal Alps, Austria. Mitteilungen aus dem Hamburgischen Zoologischen Museum und Institut, 100, 73–100.

    Dastych, H. (2004) Redescription of the glacier tardigrade Hypsibius janetscheki Ramazzotti, 1968 (Tardigrada) from the Nepal Himalayas. Entomologische Mitteilungen aus dem Zoologischen Museum Hamburg, 14, 181–194.

    Dastych, H. & Alberti, G. (1990) Redescription of Macrobiotus xerophilus (Dastych, 1978) comb. nov., with some phylogenetic notes (Tardigrada, Macrobiotidae). Mitteilungen aus dem Hamburgischen Zoologischen Museum und Institut, 87, 157–169.

    Dastych, H., Ryan, P.G. & Watkins, B.P. (1990) Notes on Tardigrada from western Dronning Maud Land (Antarctica) with a description of two new species. Entomologische Mitteilungen aus dem Zoologischen Museum Hamburg, 10, 139–140.

    Dastych, H., McInnes, S.J. & Claxton, S.K. (1998) Oreella mollis Murray, 1910 (Tardigrada): a redescription and revision of Oreella. Mitteilungen aus dem Hamburgischen Zoologischen Museum und Institut, 95, 89–113.

    Degma, P. & Opravilovà, V. (2001) Synopsis of Tardigrada for the Czech Republic. Scripta Facultatis Scientiarum Naturalium Universitatis Masarykianae Brunensis, Biology, 27, 13–39.

    de Zio Grimaldi, S. & Villora-Moreno, S. (1995) Halechiniscus chafarinensis n.sp. (Halechiniscidae), a new marine Tardigrada from the Alboran Sea (SW Mediterranean Sea). Cahiers de Biologie Marine, 36, 285–289.

    de Zio Grimaldi, S., D'Addabbo Gallo, M. & Morone De Lucia, M.R. (1998) A new Stygarctidae from South Tyrrhenian Sea (Tardigrada, Heterotardigrada). Cahiers de Biologie Marine, 39, 85–91.

    Durante, M.V. & Maucci, W. (1972) Descrizione di Hypsibius (Isohyspsibius) basalovoi sp. nov. e altre notizie sui tardigradi del Veronese. Memorie del Museo Civico di Storia Naturale di Verona, 20, 275–281.

    Edgecombe, G.D., Wilson, G.D.F., Colgan, D.J., Gray, M.R. & Cassis, G. (2000) Arthropod cladistics: combined analysis of histone H3 and U2 snRNA sequences and morphology. Cladistics, 16, 155–203.

    Gallo D’Addabbo, M., de Zio Grimaldi, S., De Lucia Morone, M.R., Pietanza, R., D’Addabbo, R. & Todaro, M.A. (1999) Diversity and dynamics of an interstitial Tardigrada population in the Meloria Shoals, Ligurian Sea, with a redescription of Batillipes similis (Heterotardigrada, Batillipedidae). Italian Journal of Zoology, 66, 51–61.

    Gallo D'Addabbo, M., D’Addabbo, R. & de Zio Grimaldi, S. (2000) Redescription of Batillipes dicrocercus Pollock, 1970 and revision of the genus Batillipes (Tardigrada, Heterotardigrada). Zoologischer Anzeiger, 239, 329–339.

    Gallo D’Addabbo, M., de Zio Grimaldi, S. & Sandulli, R. (2001) Heterotardigrada of two submarine caves in S. Domingo Island (Tremiti Island) in the Mediterranean Sea, with the description of two new species of Stygarctidae. Zoologischer Anzeiger, 240, 361–369.

    Garey, J.R., Krotec, M., Nelson, D.R. & Brooks, J. (1996) Molecular analysis support a tardigrade-arthropod association. Invertebrate Biology, 115, 79–88.

    Garey, J.R., Nelson, D.R., Mackey, L.Y. & Li, J. (1999) Tardigrade phylogeny: congruency of morphological and molecular evidence. Zoologischer Anzeiger, 238, 205–210.

    Giribert, G., Carranza, S., Baguña, J., Riutort, M. & Ribera, C. (1996) First molecular evidence for the existence of a Tardigrada + Arthropoda clade. Molecular Biology and Evolution, 13, 76–84.

    Giribert, G. & Wheeler, W.C. (2001) Some unusual small-subunit ribosomal RNA sequences of Metazoans. American Museum of Natural History, 3337, 1–14.

    Giribert, G., Distel, D.L., Polz, M., Sterrer, W. & Wheeler, W.C. (2000) Triploblastic relationships with emphasis on the acoelomates and the position of Gnathostomulida, Plathelminthes, and Chaetognatha: a combined approach of 18S rDNA sequences and morphology. Systematic Biology, 49, 539–562.

    Grimaldi de Zio, S. (1986) Evoluzione dei tardigradi marini. Nova Thalassia, 8, 449–460.

    Grimaldi de Zio, S. & D’Addabbo Gallo, M. (1987) Archechiniscus minutus sp. nov. and its systematic position within Arthrotardigrada (Tardigrada: Heterotardigrada). In: R. Bertolani (Ed.), Biology of Tardigrades, Sel. Symp. Monogr. U.Z.I., Vol. 1, Mucchi, Modena, pp. 253–260.

    Grimaldi de Zio, S., Morone de Lucia, R.M. & D’Addabbo Gallo, M. (1983) Marine tardigrades of the “Secca dell’Armeleia” (Ionian Sea), and redescription of Raiarctus colurus Renaud-Mornant 1981 (Heterotardigrada). Oebalia, IX, 33–42.

    Grimaldi de Zio, S., D’Addabbo Gallo, M., Morone De Lucia, R.M. & Daddabbo, L. (1987) Marine Arthrotardigrada and Echiniscoidea (Tardigrada, Heterotardigrada) from the Indian Ocean. Bollettino di Zoologia, 4, 347–357.

    Grimaldi de Zio, S., D’Addabbo Gallo, M. & Morone De Lucia, R.M. (1990) Revision of the genus Halechiniscus (Halechiniscidae, Arthrotardigrada). Cahiers de Biologie Marine, 31, 271–279.

    Grimaldi de Zio, S., D'Addabbo Gallo, M., Morone De Lucia, M.R. & Troccoli, A. (1990) New description of Neostygarctus acanthophorus (Tardigrada, Arthrotardigrada). Cahiers de Biologie Marine, 31, 409–416.

    Grimaldi de Zio, S., D’Addabbo Gallo, M., Morone De Lucia, R.M. & Troccoli, A. (1995/96) Hemitanarctus chimera n.g., n.sp., new Halechiniscidae from the Ionian Sea (Tardigrada, heterotardigrada). Zoologischer Anzeiger, 234, 167–174.

    Guidetti, R. & Bertolani, R. (2001a) The tardigrades of Emilia (Italy). III. Piane di Mocogno (Northern Apennines). Zoologischer Anzeiger, 240, 377–383.

    Guidetti, R. & Bertolani, R. (2001b) An evolutionary line of the Macrobiotinae (Tardigrada, Macrobiotidae): Calcarobiotus and related species. Italian Journal of Zoology, 68, 229–233.

    Guidetti, R. & Pilato, G. (2002) Revision of the genus Pseudodiphascon (Tardigrada, Macrobiotidae), with the erection of three new genera. Journal of Natural History, 37, 1679–1690.

    Guidetti, R., Bertolani, R. & Nelson, D.R. (1999) Ecological and faunistic studies on tardigrades in leaf litter of beech forests. Zoologischer Anzeiger, 238, 215–223.

    Guidetti, R., Rebecchi, L. & Bertolani, R. (2000) Cuticle structure and systematics of the Macrobiotidae (Tardigrada, Eutardigrada). Acta Zoologica, 81, 27–36.

    Guidi, A. & Rebecchi, L. (1996) Spermatozoan morphology as a character for tardigrade systematics: comparison with sclerified parts of animals and eggs in eutardigrades. Zoological Journal of the Linnean Society, 116, 101–113.

    Hansen, J.G., D’Addabbo Gallo, M.G. & Grimaldi de Zio, S. (2003) A comparison of morphological characters within the genus Rhomboarctus (Tardigrada: Heterotardigrada) with the description of two new species. Zoologischer Anzeiger, 242, 83–96.

    International Code of Zoological Nomenclature. Fourth Edition (1999) London: The International Trust for Zoological nomenclature, xxix+306 pp.

    Ito, M. (1991) Taxonomic study on the Eutardigrada from the Northern slope of Mt. Fuji, Central Japan. I. Families Calohypsibiidae and Eohypsibiidae. Proceeding of the Japanese Society of Systematic Zoology, 45, 30–43.

    Jørgensen, A. (2000) Cladistic analysis of the Echiniscidae Thulin, 1928 (Tardigrada: Heterotardigrada: Echiniscoidea). Steenstrupia, 25, 11–23.

    Jørgensen, A. & Kristensen, R.M. (2004) Molecular phylogeny of Tardigrada — investigation of the monophyly of Heterotardigrada. Molecular Phylogenetics and Evolution, 32, 666–670.

    Kathman, R.D. & Beasley, C.W. (1997) Synonymy of Platicrista cheleusis (Tardigrada: Eutardigradi: Hypsibiidae). Proceeding of the Biological Society of Washington, 110, 558–559.

    Kristensen, R.M. (1987) Generic revision of the Echiniscidae (Heterotardigrada), with a discussion of the origin of the family. In: R. Bertolani (Ed.), Biology of Tardigrades, Sel. Symp. Monogr. U.Z.I., Vol. 1, Mucchi, Modena, pp. 261–336.

    Kristensen, R.M. & Hallas, T.E. (1980) The tidal genus Echiniscoides and ist variability, with erection of Echiniscoididae fam. n. (Tardigrada). Zoologica Scripta, 9, 113–127.

    Kristensen, R.M. & Renaud-Mornant, J. (1983) Existence d’Arthrotardigrades semi-benthiques de genres nouveaux de la sous-famille des Styraconyxinae, subfam. nov. Cahiers de Biologie Marine, 24, 337–354.

    Kristensen, R.M. & Higgins, R.P. (1984) Revision of Styraconyx (Tardigrada: Halechiniscidae), with descriptions of two new species from Disko Bay, West Greenland. Smithsonian Contributions to Zoology, 391, 1–40.

    Kristensen, R.M. & Neuhaus, B. (1999) The ultrastructure of the cuticle with special attention to marine tardigrades. Acta Zoologica, 81, 27–36.

    Marcus, E. (1929) Tardigrada. In: H.G. Bronns (Ed.), Klassen und Ordnungen des Tierreichs, Leipzig, vol. 5, pp. 1–608.

    Marcus, E. (1936) Tardigrada. In: W. de Gruyter (Ed.), Das Tierreich, Berlin und Leipzig, vol. 66, pp. 1–340.

    Mass, A. & Waloszek, D. (2001) Cambrian derivatives of the early arthropod stem lineage, pentastomids, tardigrades and lobopodians — An ‘Orsten’ perspective. Zoologischer Anzeiger, 240, 451–459.

    Maucci, W. (1988) Tardigrada from Patagonia (Southern South America) with description of three new species. Revista Chilena de Entomologia, 16, 5–13.

    Maucci, W. (1996) Tardigrada of the Arctic tundra with descriptions of two new species. Zoological Journal of Linnean Society, 116, 185–204.

    McInnes, S. (1994) Rediscovery of the species Echiniscus macronyx Richters, 1907 on South Georgia, South Atlantic, its new systematic position and redescription within the genus Testechiniscus. Bollettino di Zoologia, 61, 83–87.

    Min, G.S., Kim, S.H. & Kim, W. (1998) Molecular Phylogeny of Arthropods and Their Relatives: Polyphiletic Origin of Arthropodization. Molecules and Cells, 8, 75–83.

    Moon, S.Y. & Kim, W. (1996) Phylogenetic position of the Tardigrada based on the 18S ribosomal RNA gene sequences. Zoological Journal of Linnean Society, 116, 61–69.

    Müller, K.J., Waloszek, D. & Zakharov, A. (1995) “Orsten” type phosphatized soft-integument preservation and new record from the Middle Cambrian Kuonamka Formaton in Siberia. Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen, 197, 101–118.

    Nelson, D.R. (2002) Current status of the Tardigrada: Evolution and Ecology. Integrative and Comparative Biology, 42, 652–659.

    Nelson, D.R. & McInnes, S.J. (2002) Tardigrada. In: Rundle S.D., Robertson A.L. and Schmid-Araya J.M. (Ed.), Freshwater Meiofauna, Biology and Ecology, Backhuys Publishers, Leiden, The Netherlands, pp. 177–215.

    Nelson, D.R., Marley, N.J. & Bertolani, R. (1999) Re-description of the genus Pseudobiotus (Eutardigrada, Hypsibiidae) and of the new type species Pseudobiotus kathmanae sp. n. Zoologischer Anzeiger, 238, 311–317.

    Nielsen, C. (2001) Animal Evolution, Interrelationships of the living phyla, New York: Oxford University Press Inc., 467 pp.

    Petelina, O.Y. & Tchesunov, A.V. (1983) A new representative of fauna of the White Sea, Hypsibius apelloefi (Tardigrada). Zoologicheskii Zhurnal, 62, 117–120. (in Russian)

    Pilato, G. (1969a) Evoluzione e nuova sistemazione degli Eutardigrada. Bollettino di Zoologia, 36, 327–345.

    Pilato, G. (1969b) Schema per una nuova sistemazione delle famiglie e dei generi degli Eutardigrada. Bollettino della Accademia Gioenia di Scienze Naturali, Catania, Ser. 4a, 10, 181–193.

    Pilato, G. (1972) Structure, intraspecific variability and systematic value of the buccal armature of Eutardigrada. Zeitschrift fuer Zoologische Systematik und Evolutionsforschung, Hamburg, 10, 65–78.

    Pilato, G. (1973a) L’armatura boccale di alcune specie di Macrobiotus (Eutardigradi). Bollettino delle sedute dell’Accademia Gioenia di Scienze Naturali in Catania, 12, 187–202.

    Pilato, G. (1973b) Precisazioni e rettifiche alla descrizione di alcune specie di tardigradi e considerazioni su alcuni problemi inerenti al loro studio. Bollettino della Accademia Gioenia di Scienze Naturali, Catania, 12, 157–175.

    Pilato, G. (1974) Struttura dell’armatura boccale di alcune specie di Isohypsibius (Eutardigradi). Animalia, 1, 43–58.

    Pilato, G. (1981) Analisi di nuovi caratteri nello studio degli eutardigradi. Animalia, 8, 51–57.

    Pilato, G. (1982) The systematics of Eutardigrada. A comment. Zeitschrift fuer Zoologische Systematik und Evolutionsforschung, Hamburg, 20, 271–284.

    Pilato, G. (1987) Revision of the genus Diphascon Plate, 1889, with remarks on the subfamily Itaquasconinae (Eutardigrada, Hypsibiidae). In: R. Bertolani (Ed.), Biology of Tardigrades, Sel. Symp. Monogr. U.Z.I., Vol. 1, Mucchi, Modena, pp. 337–358.

    Pilato, G. (1989) Phylogenesis and systematic arrangement of the family Calohypsibiidae Pilato, 1969 (Eutardigrada). Zeitschrift fuer Zoologische Systematik und Evolutionsforschung, Hamburg, 27, 8–13.

    Pilato, G. (1996) Redescription of Isohypsibius wilsoni and desription of two new species of Isohypsibius (Eutardigrada) from New Zealand. New Zealand Journal of Zoology, 23, 67–71.

    Pilato, G. (1997) Astatumen, a new genus of the Eutardigrada (Hypsibiidae, Itaquasconinae). Entomologische Mitteilungen aus dem Zoologischen Museum Hamburg, 12, 205–208.

    Pilato, G. (1998) Microhypsibiidae, new family of eutardigrades, and description of the new genus Fractonotus. Spixiana, 21, 129–134.

    Pilato, G. & Beasley, C.W. (1987) Haplohexapodibius seductor n. gen. n. sp. (Eutardigrada Calohypsibiidae) with remarks on the systematic position of the new genus. Animalia, 14, 65–71.

    Pilato, G. & Binda, M.G. (1977) Precisazioni e rettifiche alla descrizione di alcune specie di tardigradi (seconda nota). Animalia, 4, 35–51.

    Pilato, G. & Binda, M.G. (1987) Richtersia, nuovo genere di Macrobiotidae, e nuova definizione di Adorybiotus Maucci e Ramazzotti, 1981 (Eutardigrada). Animalia, 14, 147–152.

    Pilato, G. & Binda, M.G. (1989) Richtersius, nuovo nome generico in sostituzione di Richtersia Pilato e Binda, 1987 (Eutardigrada). Animalia, 16, 147–148.

    Pilato, G. & Binda, M.G. (1996) Additional remarks to the description of some genera of eutardigrades. Bollettino della Accademia Gioenia di Scienze Naturali, Catania, 29, 33–40.

    Pilato, G. & Binda, M.G. (1997/98) A comparison of Diphascon (D.) alpinum Murray, 1906, D. (D.) chilenense Plate, 1889 and D. (D.) pingue Marcus, 1936 (Tardigrada), and description of a new species. Zoologischer Anzeiger, 236, 181–185.

    Pilato, G. & Binda, M.G. (2003) An opinion on the genus Fujiscon Ito, 1991 (Eutardigrada, Hypsibiidae). Zootaxa, 306, 1–6.

    Pilato, G., Claxton, S. & Binda, M.G. (1989) Tardigrades from Australia. II. The evaluation of Calohypsibius ornatus (Richters, 1900) caelatus (Marcus, 1928) as valid species and description of Minibiotus fallax n.sp. (Eutardigrada). Animalia, 16, 21–27.

    Pilato, G., Binda, M.G., Napolitano, A. & Moncada, E. (2000) The specific value of Macrobiotus coronatus De Barros, 1942 and description of two new species of harmsworthi group (Eutardigrada). Bollettino dell’Accademia Gioenia di Scienze Naturali, Catania, 33, 103–120.

    Pilato, G., Binda, M.G. & Claxton, S. (2002) Itaquascon unguiculum and Itaquascon cambewarrense: two new species of eutardigrades from Australia. New Zealand Journal of Zoology, 29, 87–93.

    Pilato, G., Binda, M.G. & Lisi, O. (2004) Notes on tardigrades of the Seychelles with the description of three new species. Italian Journal of Zoology, 71, 171–178.

    Pollock, L.W. (1979) A tabular key to the species of marine Heterotardigrada. Zeszyty Naukowe Uniwersytetu Jagiellonskiego, Prace Zoologiczne, 25, 143–160.

    Pollock, L.W. (1983) A closer look at some marine Heterotardigrada, II: The morphology and taxonomy of Bathyechiniscus, with a description of B. craticulus n. sp. from the Caribbean. Bulletin of Marine Science, 33 (1), 109–117.

    Pollock, L.W. (1995) New marine tardigrades from Hawaiian beach sand and phylogeny of the family Halechiniscidae. Invertebrate Biology, 114, 220–235.

    Rahm, G. (1937) Eine neue Tardigraden-Ordnung aus den heißen Quellen von Unzen, Insel Kyushu, Japan. Zoologischer Anzeiger, 120, 65–71.

    Ramazzotti, G. (1962) Il Phylum Tardigrada. Memorie dell’Isituto Italiano di Idrobiologia Dott. Marco De Marchi, 14, 1–732.

    Ramazzotti, G. (1972) Il Phylum Tardigrada. Seconda edizione aggiornata. Memorie dell’Isituto Italiano di Idrobiologia Dott. Marco De Marchi, 28, 1–595.

    Ramazzotti, G. & Maucci, W. (1982) A history of tardigrade taxonomy. In: D.R. Nelson, (Ed.), Proceedings of the Third International Symposium on the Tardigrada. East Tennessee State University Press, Johnson City, Tennessee, pp. 11–27.

    Ramazzotti, G. & Maucci, W. (1983) Il Phylum Tardigrada. Terza edizione riveduta e corretta. Memorie dell’Isituto Italiano di Idrobiologia Dott. Marco De Marchi, 41, 1–1012.

    Rebecchi, L. (2001) The spermatozoon in tardigrades: evolution and relationships with the environment. Zoologischer Anzeiger, 240, 525–533.

    Rebecchi, L., Guidi A. & Bertolani, R. (2003) The spermatozoon of the Echiniscidae (Tardigrada, Heterotardigrada) and its phylogenetic significance. Zoomorphology, 122, 3–9.

    Regier, J.C. & Schultz, J.W. (1998) Molecular phylogeny of arthropods and the significance of the Cambrian “Explosion” for Molecular Systematics. American Zoologist, 38, 918–928.

    Regier, J. C. & Schultz, J.W. (2001) Elongation Factor-2: a useful gene for arthropod phylogenetics. Molecular Phylogenetics and Evolution, 20, 136–148.

    Renaud-Mornant, J.(1974) Une nouvelle famille de Tardigrades marins abyssaux: les Coronarctidae fam. nov. (Heterotardigrada). Comptes Rendus de l'Academie des Sciences. Paris, 278, 3087–3090.

    Renaud-Mornant, J. (1980) Description de trois espèces nouvelles du genre Tanarctus Renaud-Debyser, 1959, et création de la sous-famille des Tanarctinae, subfam. nov. (Tardigrada, Heterotardigrada). Bulletin du Muséum National d'Histoire Naturelle. 4e Serie, 2, 129–141.

    Renaud-Mornant, J. (1982a) Species diversity in marine Tardigrada. In: D.R. Nelson (Ed.), Proceedings of the Third International Symposium on the Tardigrada. East Tennessee State University Press, Johnson City, Tennessee, pp. 149–178.

    Renaud-Mornant, J. (1982b) Tardigrades marins (Arthrotardigrada) du Pacifique Sud. Bulletin du Musee d'Histoire Naturelle de Paris, 3, 799–813.

    Renaud-Mornant, J.(1982c) Sous-famille et genre nouveaux de Tardigrades marins (Arthrotardigrada). Bulletin du Muséum National d'Histoire Naturelle. 4e Serie, 4, 89–94.

    Renaud-Mornant, J. (1984) Halechiniscidae (Heterotardigrada) de la campagne Benthedi, canal du Mozambique. Bulletin du Musée d'Histoire Naturelle de Paris, 6, 67–88.

    Renaud-Mornant, J. (1987) Bathyal and abyssal Coronarctidae (Tardigrada), descriptions of new species and phylogenetical significance. In: R. Bertolani (Ed.), Biology of Tardigrades. Sel. Symp. Monogr. U.Z.I., Vol. 1, Mucchi, Modena, pp. 229–252.

    Renaud-Mornant, J. (1989) Opydorscus, un nouveau genre d'Orzeliscinae et sa signification phylogénique (Tardigrada, Arthrotardigrada). Bulletin du Museum National d'Histoire Naturelle. 4e Serie, 11, 763–771.

    Renaud-Mornant, J. & Anselme-Moizan, M.N. (1969) Stades larvaires du tardigrade marin Stygarctus bradypus Schulz et position systématique des Stygarctidae. Bulletin du Muséum National d'Histoire Naturelle. 2e Serie, 41, 883–893.

    Schultz, J.W. & Regier, J.C. (2000) Phylogenetic analysis of arthropods using two nuclear protein-encoding genes supports a crustacean + hexapod clade. Proceedings of the Royal Society of London, B, Biological Science, 267, 1011–1019.

    Schuster, R.O. & Toftner, E.C. (1982) Dominican Republic Tardigrada. In: D.R. Nelson (Ed.), Proceedings of the Third International Symposium on the Tardigrada. East Tennessee State University Press, Johnson City, Tennessee, pp. 221–235.

    Schuster, R.O., Nelson, D.R., Grigarick, A.A. & Christenberry, D. (1980) Systematic criteria of the Eutardigrada. Transactions of the American Microscopical Society, 99, 284–303.

    Toftner, E.C., Grigarick, A.A., Schuster, R.O. (1975) Analyses of scanning electron microscope images of Macrobiotus eggs. Memorie dell’Isituto Italiano di Idrobiologia Dott. Marco De Marchi, 32, 393–412.

    Villora-Moreno, S. & de Zio Grimaldi, S. (1993) Redescription and ecology of Batillipes phreaticus Renaud-Debyser, 1959 (Arthrotardigrada, Batillipedidae) in the gulf of Valencia (western mediterranean). Cahiers de Biologie Marine, 34, 387–399.

    Zrzav&, J., Mihulka, S., Kepka, P., Bezdçk, A. & Tietz, D. (1998) Phylogeny of the Metazoa based on morphological and 18S ribosomal DNA evidence. Cladistics, 14, 249–285.