Skip to main content Skip to main navigation menu Skip to site footer
Type: Monograph
Published: 2023-09-14
Page range: 1-72
Abstract views: 558
PDF downloaded: 33

Atlas of the Echiniscidae (Heterotardigrada) of the World–part I: West Palaearctic Echiniscus species

Department of Invertebrate Evolution; Faculty of Biology; Jagiellonian University; Gronostajowa 9; 30-387 Kraków; Poland; Natural History Museum of Denmark; University of Copenhagen; Øster Voldgade 5-7; DK-1350; Universitetsparken 15; DK-2100; Copenhagen; Denmark
Senckenberg Research Institute and Natural History Museum Frankfurt; Senckenberganlage 25; 60325 Frankfurt am Main; Germany
Tardigrada chaetotaxy junior synonym species delineation taxonomic inflation water bears

Abstract

Traditionally Eurocentric tardigrade taxonomy has started to dissect endemics from very few truly cosmopolitan or widely distributed species, originally described mostly from the West Palaearctic, in the last decade. Obviously, the most problematic for taxonomic identification are species in large genera containing over 100 species in the case of Tardigrada. In limno-terrestrial heterotardigrades, only Echiniscus C.A.S. Schultze, 1840 fulfils this criterion, being a perfect example of taxonomic inflation. In Echiniscidae, this phenomenon results predominantly from the historical fallacy of attaching more importance to chaetotaxy than to the analysis of dorsal plate sculpturing. In this paper, the first of a series on echiniscids of the World, we review the current state of knowledge on the West Palaearctic Echiniscus species. Echiniscus granulatus (Doyère, 1840) and E. spinulosus (Doyère, 1840) are re-described based on multiple population data. Echiniscus lapponicus Thulin, 1911 and E. militaris Murray, 1911 are provided with the first SEM and molecular data, respectively. Following synonymies are made based on analyses of ample comparative material, type series, and redescriptions: E. blumi schizofilus Bartoš, 1941 syn. nov. and E. trojanus Maucci, 1973 syn. nov. of E. blumi blumi Richters, 1903; E. inocelatus Mihelčič, 1938 syn. nov., E. heterospinosus Maucci, 1954 syn. nov. and E. egnatiae Durante Pasa & Maucci, 1979 syn. nov. of E. granulatus; Echiniscus merokensis suecicus Thulin, 1911 syn. nov., E. columinis Murray, 1911 syn. nov., E. batramiae Iharos, 1936 syn. nov., E. jagodici Mihelčič, 1951 syn. nov. and E. laterospinosus Rudescu, 1964 syn. nov. of E. merokensis merokensis Richters, 1904; E. hexacanthus Maucci, 1973 syn. nov. of E. militaris Murray, 1911; E. carusoi Pilato, 1972 syn. nov. of E. spinulosus; E. osellai Maucci, 1974 syn. nov. of E. trisetosus Cuénot, 1932. Two new nomina dubia are proposed: E. apuanus M. Bertolani, 1946 sp. dub. (and a probable synonymy with E. merokensis suggested) and E. pajstunensis Bartoš, 1941 sp. dub. Two new nomina inquirenda are established: E. marleyi Li, 2007 sp. inq. (another chaetotaxy-based morphotype of the Echiniscus blumi-canadensis complex) and E. punctus McInnes, 1995 sp. inq. (the lack of reliable morphological criteria separating it from E. granulatus). We summarise the morphological, phylogenetic and biogeographic information for the West Palaearctic Echiniscus species, and conclude with a total of 21 valid and identifiable taxa. We predict this number will decrease further with solving the species delimitation issues within the Echiniscus blumi-canadensis complex. Among these 21 taxa, 13 species (62%) are to be found solely in the Western Palaearctic and/or entire Holarctic regions. This augments the many recent findings that tardigrades are typically biogeographically structured and form clearly defined faunae.

 

References

  1. Bartoš, E. (1934) Prispevek k poznani Tardigrad ČSR. Časopis Československé Společnosti Entomologické, 31, 99–107.
  2. Bartoš, E. (1935) Neue Echiniscus-Arten der nördlichen Slowakei. Zoologischer Anzeiger, 111, 139–143.
  3. Bartoš, E. (1937) Die Tardigraden von Cap Caliacra (Rumänien). Zoologischer Anzeiger, 118 (11–12), 301–304.
  4. Bartoš, E. (1939) Tardigraden aus Böhmen und der Slowakei. Zoologischer Anzeiger, 127 (3–4), 95–101.
  5. Bartoš, E. (1940) Additamenta cognitionem faunae Tardigradorum Bohemiae. I. Tardigrada muscorum in montibus Brdy collectorum. Acta Societatis Zoologicae Bohemoslovenicae, 8, 16–23.
  6. Bartoš, E. (1941) Studien über die Tardigraden des Karpathengebietes. Zoologische Jahrbücher Abteilung für Systematik, Ökologie und Geographie der Tiere, 74 (5–6), 435–472.
  7. Bartylak, T., Kayastha, P., Roszkowska, M., Kepel, A., Kepel, M. & Kaczmarek, Ł. (2022) Tardigrades of the Ivohibory forest (south-central Madagascar) with a description of a new Bryodelphax species. European Zoological Journal, 89 (1), 423–436. https://doi.org/10.1080/24750263.2022.2042404
  8. Beasley, C.W. (1999) A new species of Echiniscus (Tardigrada, Echiniscidae) from Northern Yunnan Province, China. Zoologischer Anzeiger, 238 (3–4), 135–138.
  9. Beasley, C.W. & Miller, W.R. (2007) Tardigrada of Xinjiang Uygur Autonomous Region, China. Journal of Limnology, 66 (Supplment 1), 49–55. https://doi.org/10.4081/jlimnol.2007.s1.49
  10. Bertolani, M. (1941) Contributo alla conoscenza dei tardigradi d’Italia. Bollettino di Zoologia, 12 (1), 57–66. https://doi.org/10.1080/11250004109440004
  11. Bertolani, M. (1946) Ulteriore contributo alla conoscenza dei tardigradi italiani. Atti della Societa Toscana di Scienze Naturali, 54, 1–4.
  12. Bertrand, M. (1975) Les biotopes des tardigrades ‘terrestres’ dans une Hêtraie du Massif de L’Aigoual (Cévennes Méridionales). Vie et Milieu, 25 (2), 299–314.
  13. Bilgin, R. (2011) Back to the suture: the distribution of intraspecific genetic diversity in and around Anatolia. International Journal of Molecular Sciences, 12 (6), 4080–4103. https://doi.org/10.3390/ijms12064080
  14. Binda, M.G. & Guglielmino, A. (1982) Tardigradi muscicoli e dulcacquicoli di Sardegna. Animalia, 9 (1–3), 199–211.
  15. Binda, M.G. & Pilato, G. (1969) Tardigradi muscicoli delle Isole Eolie (Sicilia). Bollettino delle sedute dell’Accademia Gioenia di Scienze naturale Catania, Serie IV, 9, 634–651.
  16. Binda, M.G. & Pilato, G. (1994) Echiniscus peruvianus, nuova specie di eterotardigrado del Sudamerica. Animalia, 21 (1–3), 93–96.
  17. Binda, M.G. & Pilato, G. (1995) Some notes on African tardigrades with a description of two new species. Tropical Zoology, 8 (2), 367–372. https://doi.org/10.1080/03946975.1995.10539294
  18. Biserov, V.I. (1991) An annotated list of Tardigrada from European Russia. Zoologische Jahrbücher Abteilung für Systematik Ökologie und Geographie der Tiere, 118, 193–216.
  19. Bochnak, M., Vončina, K., Kristensen, R.M. & Gąsiorek, P. (2020) Continued exploration of Tanzanian rainforests reveals a new echiniscid species (Heterotardigrada). Zoological Studies, 59, 18. https://doi.org/10.6620/ZS.2020.59-18
  20. Cakil, Z.V., Garlasché, G., Iakovenko, N., Di Cesare, A., Eckert, E.M., Guidetti, R., Hamdan, L., Janko, K., Lukashanets, D., Rebecchi, L., Schiaparelli, S., Sforzi, T., Štefková Kašparová, E., Velasco-Castrillón, A., Walsh, E.J. & Fontaneto, D. (2021) Comparative phylogeography reveals consistently shallow genetic diversity in a mitochondrial marker in Antarctic bdelloid rotifers. Journal of Biogeography, 48 (7), 1797–1809. https://doi.org/10.1111/jbi.14116
  21. Campbell, L.I., Rota-Stabelli, O., Edgecombe, G.D., Marchioro, T., Longhorn, S.J., Telford, M.J., Philippe, H., Rebecchi, L., Peterson, K.J. & Pisani, D. (2011) MicroRNAs and phylogenomics resolve the relationships of Tardigrada and suggest that velvet worms are the sister group of Arthropoda. PNAS, 108 (38), 15920–15924. https://doi.org/10.1073/pnas.1105499108
  22. Casquet, J.T., Thebaud, C. & Gillespie, R.G. (2012) Chelex without boiling, a rapid and easy technique to obtain stable amplifiable DNA from small amounts of ethanol-stored spiders. Molecular Ecology Resources, 12 (1), 136–141. https://doi.org/10.1111/j.1755-0998.2011.03073.x
  23. Cesari, M., Montanari, M., Kristensen, R.M., Bertolani, R., Guidetti, R. & Rebecchi, L. (2020) An integrated study of the biodiversity within the Pseudechiniscus suillus-facettalis group (Heterotardigrada: Echiniscidae). Zoological Journal of the Linnean Society, 188 (3), 717–732. https://doi.org/10.1093/zoolinnean/zlz045
  24. Claps, M.C. & Rossi, G.C. (1988) Tardígrados de Argentina VI. Iheringia, Série Zoologia, 67, 3–11.
  25. Claxton, S.K. (1996) Sexual dimorphism in Australian Echiniscus (Tardigrada, Echiniscidae) with descriptions of three new species. Zoological Journal of the Linnean Society, 116 (1–2), 13–33. https://doi.org/10.1111/j.1096-3642.1996.tb02330.x
  26. Claxton, S.K. & Dastych, H. (2017) A new bisexual species of Echiniscus C.A.S. Schultze,1840 (Heterotardigrada: Echiniscidae) from Tasmania, Australia. Entomologie heute, 29, 105–119.
  27. Cuénot, L. (1932) Tardigrades. In: Lechevalier, P. (Ed.), Faune de France, 24, pp. 1–96.
  28. Čuček, M. (1985) Tardigradi Cerkniškega Jezera in okolice. Biološki Vestnik, 33 (2), 1–10.
  29. da Cunha, A.X. & do Nascimento Ribeiro, F. (1962) A fauna de tardígrados da Ilha da Madeira. Memórias e Estudos do Museu Zoológico da Universidade de Coimbra, 279, 1–24.
  30. Dastych, H. (1980) Niesporczaki (Tardigrada) Tatrzańskiego Parku Narodowego. Monografie Fauny Polski, 9, 1–232.
  31. Dastych, H. (1986) Echiniscus rackae sp. n., a new species of Tardigrada from the Himalayas. Entomologische Mitteilungen aus dem Zoologischen Staatsinstitut und Zoologischen Museum Hamburg, 8 (127), 246–250.
  32. Dastych, H. (1988) The Tardigrada of Poland. Monografie Fauny Polski, 16, 1–255.
  33. Dastych, H. (1999a) Eine Neue Art der Gattung Mopsechiniscus Du Bois-Reymond Marcus, 1944 (Tardigrada) aus den Anden von Venezuela. Acta biologica Benrodis, 10, 91–101.
  34. Dastych, H. (1999b) Redescription of the sub-Antarctic tardigrade Mopsechiniscus imberbis (Richters, 1908) (Tardigrada). Mitteilungen aus den Hamburgischen Zoologischen Museum und Institut, 96, 21–35.
  35. Dastych, H. (2001) Notes on the revision of the genus Mopsechiniscus (Tardigrada). Zoologischer Anzeiger, 240 (3–4), 299–308. https://doi.org/10.1078/0044-5231-00037
  36. Dastych, H. (2015) Checklisten der Fauna Österreichs, No. 8: Tardigrada. In: Winkler, H. & Stuessy, T. (Eds), Biosystematics and Ecology Series. No. 31. Verlag der Österreichischen Akademie der Wissenschaften, pp. 1–25.
  37. Dastych, H. & Kristensen, R.M. (1995) Echiniscus ehrenbergi sp. n., a new water bear from the Himalayas. Entomologische Mitteilungen aus dem Zoologischen Museum Hamburg, 11 (152), 221–230.
  38. de Barros, R. (1942) Tardígrados do estado de São Paulo, Brasil. I. Introdução. Gêneros ‘Echiniscus’ e ‘Pseudechiniscus’. Revista Brasileira de Biologia, 2 (3), 257–269.
  39. Degma, P. & Guidetti, R. (2007) Notes to the current checklist of Tardigrada. Zootaxa, 1579 (1), 41–53. https://doi.org/10.11646/zootaxa.1579.1.2
  40. Degma, P. & Guidetti, R. (2023) Actual checklist of Tardigrada species. 42nd Edition. Accessed 10.01.2023. https://doi.org/10.25431/11380_1178608
  41. DeMilio, E., Tumanov, D.V., Lawton, C. & Hansen, J.G. (2022) Observations of Irish Parechiniscus Cuénot, 1926 (Heterotardigrada: Echiniscidae) convey new information (and questions) about the genus. Biology and Environment: Proceedings of the Royal Irish Academy, 122B (3), 161–179. https://doi.org/10.1353/bae.2022.0011
  42. Doyère, M.L. (1840) Mémoire sur les tardigrades. Annales des Sciences Naturelles, Serie 2, Zoologie, 14, 269–362.
  43. Durante, M.V. & Maucci, W. (1972) Descrizione di Hypsibius (Isohypsibius) basalovoi sp. nov. e altre notizie su tardigradi del Veronese. Memorie del Museo Civico di Storia Naturale di Verona, 20, 275–281.
  44. Durante Pasa, M.V. & Maucci, W. (1975a) Tardigradi muscicoli dell’Istria con descrizione di due specie nuove. In: Higgins, R.P. (Ed.), International Symposium on Tardigrades, 1974. Memorie dell’Istituto Italiano di Idrobiologia, 32 (Supplement), 69–91.
  45. Durante Pasa, M.V. & Maucci, W. (1975b) Descrizione di tre nuove specie di Tardigradi della Scandinavia. Atti della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale in Milano, 116 (3–4), 244–250.
  46. Durante Pasa, M.V. & Maucci, W. (1979a) Tardigradi muscicoli della Grecia. Zeszyty Naukowe Uniwersytetu Jagiellońskiego, 529 (25), 19–45.
  47. Durante Pasa, M.V. & Maucci, W. (1979b) Moss Tardigrada from the Scandinavian Peninsula. Zeszyty Naukowe Uniwersytetu Jagiellońskiego, 529 (25), 47–85.
  48. Ehrenberg, C.G. (1853) Diagnoses novarum formarum. Verhandlungen der Königlichen Preussische Akademie der Wissenschaften zu Berlin, 8, 526–533.
  49. Faurby, S., Jørgensen, A., Kristensen, R.M. & Funch, P. (2011) Phylogeography of North Atlantic intertidal tardigrades: refugia, cryptic speciation and the history of the Mid-Atlantic islands. Journal of Biogeography, 38 (8), 1613–1624. https://doi.org/10.1111/j.1365-2699.2011.02533.x
  50. Fernández-Palacios, J.M., de Nascimento, L., Otto, R., Delgado, J.D., García-del-Rey, E., Arévalo, J.R. & Whittaker, R.J. (2011) A reconstruction of Palaeo-Macaronesia, with particular reference to the long-term biogeography of the Atlantic island laurel forests. Journal of Biogeography, 38 (2), 226–246. https://doi.org/10.1111/j.1365-2699.2010.02427.x
  51. Fontoura, P. (1982) Deux nouvelles espèces de tardigrades muscicoles du Portugal. Publicações do Instituto de Zoologia “Dr. Augusto Nobre”, Faculdade de Ciências do Porto, 165, 5–19.
  52. Fontoura, P. & Morais, P. (2011) Assessment of traditional and geometric morphometrics for discriminating cryptic species of the Pseudechiniscus suillus complex (Tardigrada, Echiniscidae). Journal of Zoological Systematics and Evolutionary Research, 49 (Supplement 1), 26–33. https://doi.org/10.1111/j.1439-0469.2010.00594.x
  53. Fontoura, P., Pilato, G. & Lisi, O. (2008) Echiniscidae (Tardigrada, Heterotardigrada) from Faial and Pico Islands, the Azores, with the description of two new species. Zootaxa, 1693 (1), 49–61. https://doi.org/10.11646/zootaxa.1693.1.4
  54. Gąsiorek, P. (2023) Eventually tested: Phylogenetic position of “Testechiniscus” meridionalis (Murray, 1906) (Heterotardigrada) revealed. Zoologischer Anzeiger, 304, 49–60. https://doi.org/10.1016/j.jcz.2023.02.004
  55. Gąsiorek, P., Blagden, B. & Michalczyk, Ł. (2019a) Towards a better understanding of echiniscid intraspecific variability: a redescription of Nebularmis reticulatus (Murray, 1905) (Heterotardigrada: Echiniscoidea). Zoologischer Anzeiger, 283, 242–255. https://doi.org/10.1016/j.jcz.2019.08.003
  56. Gąsiorek, P., Bochnak, M., Vončina, K. & Michalczyk, Ł. (2021d) Phenotypically exceptional Echiniscus species (Heterotardigrada: Echiniscidae) from the Neotropics (Argentina). Zoologischer Anzeiger, 294, 210–228. https://doi.org/10.1016/j.jcz.2021.08.003
  57. Gąsiorek, P. & Degma, P. (2018) Three Echiniscidae species (Tardigrada: Heterotardigrada) new to the Polish fauna, with the description of a new gonochoristic Bryodelphax Thulin, 1928. Zootaxa, 4410 (1), 77–96. https://doi.org/10.11646/zootaxa.4410.1.4
  58. Gąsiorek, P., Jackson, K., Meyer, H., Zając, K., Kristensen, R.M., Nelson, D.R. & Michalczyk, Ł. (2019d) Echiniscus virginicus complex: the first case of pseudocryptic allopatry and pantropical distribution in tardigrades. Biological Journal of the Linnean Society, 128 (4), 789–805. https://doi.org/10.1093/biolinnean/blz147
  59. Gąsiorek, P. & Kristensen, R.M. (2018) Echiniscidae (Heterotardigrada) of Tanzania and Uganda. Tropical Zoology, 31 (3), 131–160. https://doi.org/10.1080/03946975.2018.1477350
  60. Gąsiorek, P. & Michalczyk, Ł. (2020) Echiniscus siticulosus (Echiniscidae: spinulosus group), a new tardigrade from Western Australian scrub. New Zealand Journal of Zoology, 47 (2), 87–105. https://doi.org/10.1080/03014223.2019.1603166
  61. Gąsiorek, P., Morek, W., Stec, D. & Michalczyk, Ł. (2019b) Untangling the Echiniscus Gordian knot: paraphyly of the “arctomys group” (Heterotardigrada: Echiniscidae). Cladistics, 35 (6), 633–653. https://doi.org/10.1111/cla.12377
  62. Gąsiorek, P., Oczkowski, A., Blagden, B., Kristensen, R.M., Bartels, P.J., Nelson, D.R., Suzuki, A.C. & Michalczyk, Ł. (2021c) New Asian and Nearctic Hypechiniscus species (Heterotardigrada: Echiniscidae) indicate a pseudocryptic horn of plenty. Zoological Journal of the Linnean Society, 192 (3), 794–852. https://doi.org/10.1093/zoolinnean/zlaa110
  63. Gąsiorek, P., Stec, D., Morek, W. & Michalczyk, Ł. (2017) An integrative redescription of Echiniscus testudo (Doyère, 1840), the nominal taxon for the class Heterotardigrada (Ecdysozoa: Panarthropoda: Tardigrada). Zoologischer Anzeiger, 270, 107–122. https://doi.org/10.1016/j.jcz.2017.09.006
  64. Gąsiorek, P., Stec, D., Zawierucha, K. Kristensen, R.M. & Michalczyk, Ł. (2018) Revision of Testechiniscus Kristensen, 1987 (Heterotardigrada: Echiniscidae) refutes the polar-temperate distribution of the genus. Zootaxa, 4472 (2), 261–297. https://doi.org/10.11646/zootaxa.4472.2.3
  65. Gąsiorek, P., Vončina, K., Bochnak, M., Surmacz, B., Morek, W. & Michalczyk, Ł. (2022) Echiniscidae (Heterotardigrada) of South Africa. Zootaxa, 5156 (1), 1–238. https://doi.org/10.11646/zootaxa.5156.1.1
  66. Gąsiorek, P., Vončina, K., Ciosek, J., Veloso, M., Fontoura, P. & Michalczyk, Ł. (2021b) New Indomalayan Nebularmis species (Heterotardigrada: Echiniscidae) provoke a discussion on its intrageneric diversity. Zoological Letters, 7, 6. https://doi.org/10.1186/s40851-021-00172-0
  67. Gąsiorek, P., Vončina, K., Kristensen, R.M. & Michalczyk, Ł. (2021e) High mountain echiniscid (Heterotardigrada) fauna of Taiwan. Zoological Studies, 60, 70. https://doi.org/10.6620/ZS.2021.60-70
  68. Gąsiorek, P., Vončina, K. & Michalczyk, Ł. (2019c) Echiniscus testudo (Doyère, 1840) in New Zealand: anthropogenic dispersal or evidence for the ‘Everything is Everywhere’ hypothesis? New Zealand Journal of Zoology, 46 (2), 174–181. https://doi.org/10.1080/03014223.2018.1503607
  69. Gąsiorek, P., Vončina, K. & Michalczyk, Ł. (2020) An overview of the sexual dimorphism in Echiniscus (Heterotardigrada, Echiniscoidea), with the description of Echiniscus masculinus sp. nov. (the virginicus complex) from Borneo. Zoosystematics and Evolution, 96 (1), 103–113. https://doi.org/10.3897/zse.96.49989
  70. Gąsiorek, P., Vončina, K., Nelson, D.R. & Michalczyk, Ł. (2021a) The importance of being integrative: a remarkable case of synonymy in the genus Viridiscus (Heterotardigrada: Echiniscidae). Zoological Letters, 7, 13. https://doi.org/10.1186/s40851-021-00181-z
  71. Giribet, G. & Edgecombe, G.D. (2017) Current understanding of Ecdysozoa and its internal phylogenetic relationships. Integrative and Comparative Biology, 57 (3), 455–466. https://doi.org/10.1093/icb/icx072
  72. Grobys, D., Roszkowska, M., Gawlak, M., Kmita, H., Kepel, A., Kepel, M., Parnikoza, I., Bartylak, T. & Kaczmarek, Ł. (2020) High diversity in the Pseudechiniscus suillus–facettalis complex (Heterotardigrada: Echiniscidae) with remarks on the morphology of the genus Pseudechiniscus. Zoological Journal of the Linnean Society, 188 (3), 733–752. https://doi.org/10.1093/zoolinnean/zlz171
  73. Gross, V., Treffkorn, S., Reichelt, J., Epple, L., Lüter, C. & Mayer, G. (2019) Miniaturization of tardigrades (water bears): Morphological and genomic perspectives. Arthropod Structure & Development, 48, 12–19. https://doi.org/10.1016/j.asd.2018.11.006
  74. Guidetti, R., Cesari, M., Bertolani, R., Altiero, T. & Rebecchi, L. (2019a) High diversity in species, reproductive modes and distribution within the Paramacrobiotus richtersi complex (Eutardigrada, Macrobiotidae). Zoological Letters, 5, 1. https://doi.org/10.1186/s40851-018-0113-z
  75. Guidetti, R., Massa, E., Bertolani, R., Rebecchi, L. & Cesari, M. (2019b) Increasing knowledge of Antarctic biodiversity: new endemic taxa of tardigrades (Eutardigrada; Ramazzottiidae) and their evolutionary relationships. Systematics and Biodiversity, 17 (6), 573–593. https://doi.org/10.1080/14772000.2019.1649737
  76. Guil, N. (2002) Diversity and distribution of tardigrades (Bilateria, Tardigrada) from the Iberian Peninsula, Balearic Islands and Chafarinas Islands. Graellsia, 58 (2), 75–94. https://doi.org/10.3989/graellsia.2002.v58.i2.279
  77. Guil, N. (2008) New records and within-species variability of Iberian tardigrades (Tardigrada), with comments on the species from the Echiniscus blumi-canadensis series. Zootaxa, 1757 (1), 1–30. https://doi.org/10.11646/zootaxa.1757.1.1
  78. Guil, N. (2011) Molecular approach to micrometazoans. Are they here, there and everywhere? In: Fontaneto, D. (Ed.), Biogeography of microscopic organisms: Is everything small everywhere?, Chapter 14, pp. 284–306. https://doi.org/10.1017/CBO9780511974878.015
  79. Guil, N. & Giribet, G. (2009) Fine scale population structure in the Echiniscus blumi-canadensis series (Heterotardigrada, Tardigrada) in an Iberian mountain range—When morphology fails to explain genetic structure. Molecular Phylogenetics and Evolution, 51 (3), 606–613. https://doi.org/10.1016/j.ympev.2009.02.019
  80. Guil, N., Machordom, A. & Guidetti, R. (2013) High level of phenotypic homoplasy amongst eutardigrades (Tardigrada) based on morphological and total evidence phylogenetic analyses. Zoological Journal of the Linnean Society, 169 (1), 1–26. https://doi.org/10.1111/zoj.12046
  81. Hall, T.A. (1997) BIOEDIT: a user-friendly biological sequence alignment editor and analysis program for Windows 95/98/NT. Nucleic Acids Symposium Series, 41, 95–98.
  82. Heinis, F. (1908) Tardigraden der Schweiz. Zoologischer Anzeiger, 32 (22), 633–638.
  83. Hoang, D.T., Chernomor, O., von Haeseler, A., Minh, B.Q. & Vinh, L.S. (2018) UFBoot2: Improving the ultrafast bootstrap approximation. Molecular Biology and Evolution, 35 (2), 518–522. https://doi.org/10.1093/molbev/msx281
  84. Horning, D.S., Schuster, R.O. & Grigarick, A.A. (1978) Tardigrada of New Zealand. New Zealand Journal of Zoology, 5 (2), 185–280. https://doi.org/10.1080/03014223.1978.10428316
  85. ICZN (1999) International Code of Zoological Nomenclature, fourth edition. The International Trust for Zoological Nomenclature, London, UK, 306 p.
  86. Iharos, A. (1936) Zwei neue Tardigraden-Arten. Zoologischer Anzeiger, 115 (7–8), 218–220.
  87. Ito, M. (1993) Taxonomic study on the class Heterotardigrada (Tardigrada) from the northern slope of Mt. Fuji, Central Japan. Edaphologia, 50, 1–13.
  88. Jørgensen, A., Faurby, S., Persson, D.K., Halberg, K.A., Kristensen, R.M. & Møbjerg, N. (2013) Genetic diversity in the parthenogenetic reproducing tardigrade Echiniscus testudo (Heterotardigrada: Echiniscoidea). Journal of Limnology, 72 (1), 136–143. https://doi.org/10.4081/jlimnol.2013.s1.e17
  89. Jørgensen, A., Møbjerg, N. & Kristensen, R.M. (2007) A molecular study of the tardigrade Echiniscus testudo (Echiniscidae) reveals low DNA sequence diversity over a large geographical area. Journal of Limnology, 66 (Supplement 1), 77–83. https://doi.org/10.4081/jlimnol.2007.s1.77
  90. Jørgensen, A., Møbjerg, N. & Kristensen, R.M. (2011) Phylogeny and evolution of the Echiniscidae (Echiniscoidea, Tardigrada)–an investigation of the congruence between molecules and morphology. Journal of Zoological Systematics and Evolutionary Research, 49 (1), 6–16. https://doi.org/10.1111/j.1439-0469.2010.00592.x
  91. Jönsson, K.I. (2007) Long-term experimental manipulation of moisture conditions and its impact on moss-living tardigrades. Journal of Limnology, 66 (Supplement 1), 119–125. https://doi.org/10.4081/jlimnol.2007.s1.119
  92. Kaczmarek, Ł., Kayastha, P., Gawlak, M., Mioduchowska, M. & Roszkowska, M. (2021) An integrative description of Diploechiniscus oihonnae (Richters, 1903) population from near the original type locality in Merok (Norway). Zootaxa, 4964 (1), 83–102. https://doi.org/10.11646/zootaxa.4964.1.4
  93. Kaczmarek, Ł., Kayastha, P., Gawlak, M., Mioduchowska, M. & Roszkowska, M. (2022) An integrative redescription of Echiniscus quadrispinosus quadrispinosus Richters, 1902 (Heterotardigrada, Echiniscidae) from the terra typica in Taunus Mountain Range (Europe; Germany). European Journal of Taxonomy, 823 (1), 102–124. https://doi.org/10.5852/ejt.2022.823.1819
  94. Kaczmarek, Ł. & Michalczyk, Ł. (2010) The genus Echiniscus Schultze 1840 (Tardigrada) in Costa Rican (Central America) rain forests with descriptions of two new species. Tropical Zoology, 23 (1), 91–106.
  95. Kaczmarek, Ł., Michalczyk, Ł. & McInnes, S.J. (2016) Annotated zoogeography of non-marine Tardigrada. Part III: North America and Greenland. Zootaxa, 4203 (1), 1–249. https://doi.org/10.11646/zootaxa.4203.1.1
  96. Kalyaanamoorthy, S., Minh, B.Q., Wong, T.K.F., von Haeseler, A. & Jermiin, L.S. (2017) ModelFinder: fast model selection for accurate phylogenetic estimates. Nature Methods, 14, 587–589. https://doi.org/10.1038/nmeth.4285
  97. Katoh, K., Misawa, K., Kuma, K. & Miyata, T. (2002) MAFFT: a novel method for rapid multiple sequence alignment based on fast Fourier transform. Nucleic Acids Research, 30 (14), 3059–3066. https://doi.org/10.1093/nar/gkf436
  98. Katoh, K. & Toh, H. (2008) Recent developments in the MAFFT multiple sequence alignment program. Briefings in Bioinformatics, 9 (4), 286–298. https://doi.org/10.1093/bib/bbn013
  99. Kristensen, R.M. (1987) Generic revision of the Echiniscidae (Heterotardigrada), with a discussion of the origin of the family. In: Bertolani, R. (Ed.), Biology of Tardigrades. Selected Symposia and Monographs U.Z.I., 1, pp. 261–335.
  100. Kruskal, Jr., J.B. (1956) On the shortest spanning subtree of a graph and the traveling salesman problem. Proceedings of the American Mathematical Society, 7 (1), 48–50. https://doi.org/10.2307/2033241
  101. Lanfear, R., Calcott, B., Ho, S.Y. & Guindon, S. (2012) PartitionFinder: combined selection of partitioning schemes and substitution models for phylogenetic analyses. Molecular Biology and Evolution, 29 (6), 1695–1701. https://doi.org/10.1093/molbev/mss020
  102. Lanfear, R., Frandsen, P.B., Wright, A.M., Senfeld, T. & Calcott, B. (2017) PartitionFinder 2: new methods for selecting partitioned models of evolution for molecular and morphological phylogenetic analyses. Molecular Biology and Evolution, 34 (3), 772–773. https://doi.org/10.1093/molbev/msw260
  103. Lattes, A. (1975) Differences in the sculpture between adults and juveniles of Echiniscus: a note on the importance of quantitative parameters in the systematics of the Echiniscidae. In: Higgins, R.P. (Ed.), International Symposium on Tardigrades, 1974. Memorie dell’Istituto Italiano di Idrobiologia, 32 (Supplement), 171–176.
  104. Lattes, A. & Gallelli, F.T. (1972) Variabilita intraspecifica di Echiniscus (E.) quadrispinosus Richters e differenziazione di questa specie da Echiniscus (E.) merokensis Richters. Bollettino dei Musei e degli Istituti Biologici dell’Università di Genova, 40, 137–152.
  105. Li, X. (2007) Tardigrades from the Tsinling Mountains, central China with descriptions of two new species of Echiniscidae (Tardigrada). Journal of Natural History, 41 (41–44), 2719–2739. https://doi.org/10.1080/00222930701711046
  106. Liegeois, M., Sartori, M. & Schwander, T. (2021) Extremely widespread parthenogenesis and a trade-off between alternative forms of reproduction in mayflies (Ephemeroptera). Journal of Heredity, 112 (1), 45–57. https://doi.org/10.1093/jhered/esaa027
  107. Linnæus, C. (1758) Systema Naturae per Regna Triae Naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. 10th Edition. Laurentii Salvii, Holmiae, IV, 824 pp. https://doi.org/10.5962/bhl.title.542
  108. Marcus, E. (1928) Spinnentiere oder Arachnoidea. IV. Bärtierchen (Tardigrada). Tierwelt Deutschlands und der angrenzenden Meeresteile Jena, 12, 1–230.
  109. Marcus, E. (1930) Beitrage zur Tardigradensystematik. Zoologische Jahrbücher Abteilung für Systematik Ökologie und Geographie der Tiere, 59, 363–386.
  110. Marcus, E. (1936) Tardigrada. Das Tierreich, 66, 1–340.
  111. Maucci, W. (1954) Tardigradi nuovi della fauna italiana. Atti della Società Italiana di Scienze Naturali, 97, 576–585.
  112. Maucci, W. (1972) Due nuove specie di tardigradi muscicoli dell’Istria. Memorie del Museo Civico di Storia Naturale di Verona, 20, 1–8.
  113. Maucci, W. (1973) Tardigradi muscicoli della Turchia. Memorie del Museo Civico di Storia Naturale di Verona, 20, 169–221.
  114. Maucci, W. (1973–74) Tardigradi muscicoli del Carso Triestino. Bollettino della Societa Adriatica di Scienze di Trieste, 59 (1), 107–150.
  115. Maucci, W. (1974) Tardigradi muscicoli della Turchia (Secondo contributo). Bollettino del Museo Civico di Storia Naturale di Verona, 1, 255–275.
  116. Maucci, W. (1983) Echiniscus bisculptus n. sp., del Marocco, ed E. lichenorum n. sp., del Portogallo. Atti della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale in Milano, 124 (3–4), 257–261.
  117. Maucci, W. (1985) Materiali per una revisione del genere Echiniscus Schultze, 1840. I. Il complesso blumi (Heterotardigrada, Echiniscidae). Bollettino del Museo Civico di Storia Naturale di Verona, 12, 109–139.
  118. Maucci, W. (1986) Tardigrada. Fauna d’Italia, Bologna, Calderini, 24, 1–388.
  119. Maucci, W. (1987) A contribution to the knowledge of the North American Tardigrada with emphasis on the fauna of Yellowstone National Park (Wyoming). In: Bertolani, R. (Ed.), Biology of Tardigrades. Selected Symposia and Monographs U.Z.I., 1, pp. 187–210.
  120. Maucci, W. & Durante, M.V. (1984) I Tardigradi della Penisola Iberica. Miscellanea Zoologica Hungarica, 8, 67–80.
  121. Maucci, W. & Durante Pasa, M.V. (1982) Tardigradi della Grecia (Secondo contributo), con particolare riferimento alla fauna dell’Isola di Creta. Bollettino del Museo Civico di Storia Naturale di Verona, 9, 479–488.
  122. Maucci, W. & Durante Pasa, M.V. (1985) I Tardigradi della fauna Portoghese. Anais da Faculdade de Ciências do Porto, 65 (1–4), 127–174.
  123. McInnes, S.J. (1994) Zoogeographic distribution of terrestrial/freshwater tardigrades from current literature. Journal of Natural History, 28 (2), 257–352. https://doi.org/10.1080/00222939400770131
  124. McInnes, S.J. (1995) Tardigrades from Signy Island, South Orkney Islands, with particular reference to freshwater species. Journal of Natural History, 29 (6), 1419–1445. https://doi.org/10.1080/00222939500770601
  125. Meier, T. (2017) A checklist of Norwegian Tardigrada. Fauna Norvegica, 37, 25–42. https://doi.org/10.5324/fn.v37i0.2269
  126. Michalczyk, Ł. & Kaczmarek, Ł. (2013) The Tardigrada Register: a comprehensive online data repository for tardigrade taxonomy. Journal of Limnology, 72 (Supplement 1), 175–181. https://doi.org/10.4081/jlimnol.2013.s1.e22
  127. Michalczyk, Ł., Wełnicz, W., Frohme, M. & Kaczmarek, Ł. (2012) Redescriptions of three Milnesium Doyère, 1840 taxa (Tardigrada: Eutardigrada: Milnesiidae), including the nominal species for the genus. Zootaxa, 3154 (1), 1–20. https://doi.org/10.11646/zootaxa.3154.1.1
  128. Mihelčič, F. (1938) Beiträge zur Kenntnis der Tardigraden Jugoslawiens. Zoologischer Anzeiger, 123 (10–11), 316–318.
  129. Mihelčič, F. (1939) Beiträge zur Kenntnis der Tardigraden Jugoslawiens. Prirodoslovne Razprave, 3, 331–345.
  130. Mihelčič, F. (1951) Beitrag zur Systematik de Tardigraden. Archivio Zoologico Italiano, 36, 57–103.
  131. Mihelčič, F. (1955) Zwei neue Tardigradenarten aus Spanien. Zoologischer Anzeiger, 155 (11–12), 309–311.
  132. Mihelčič, F. (1964) Eine neue Echiniscus-Art (Tardigrada) aus dem Karst (Echiniscus (E.) inocellatus n. sp.). Zoologischer Anzeiger, 172 (3), 240–242.
  133. Mihelčič, F. (1967) Ein Beitrag zur Kenntnis der Tardigraden Argentiniens. Verhandlungen der Zoologisch-Botanischen Gesellschaft in Wien, 107, 43–56.
  134. Mihelčič, F. (1967) Ein Beitrag zur Kenntnis der Tardigrada der Steiermark. Mitteilungen des Naturwissenschaftlichen Vereines für Steiermark, 97, 67–75.
  135. Mihelčič, F. (1969) Zur Kenntnis der Tardigraden Osttirols. Veröffentlichungen des Museum Ferdinandeum in Innsbruck, 49, 113–130.
  136. Miller, W.R., Claxton, S.K. & Heatwole, H.F. ( 1999) Tardigrades of the Australian Antarctic Territories: males in the genus Echiniscus (Tardigrada: Heterotardigrada). Zoologischer Anzeiger, 238 (3–4), 303–309.
  137. Morek, W., Blagden, B., Kristensen, R.M. & Michalczyk, Ł. (2020) The analysis of inter- and intrapopulation variability of Milnesium eurystomum Maucci, 1991 reveals high genetic divergence and a novel type of ontogenetic variation in the order Apochela. Systematics and Biodiversity, 18 (6), 614–632. https://doi.org/10.1080/14772000.2020.1771469
  138. Morek, W., Surmacz, B., López-López, A. & Michalczyk, Ł. (2021) “Everything is not everywhere”: Time-calibrated phylogeography of the genus Milnesium (Tardigrada). Molecular Ecology, 30 (14), 3590–3609. https://doi.org/10.1111/mec.15951
  139. Morek, W., Stec, D., Gąsiorek, P., Surmacz, B. & Michalczyk, Ł. (2019) Milnesium tardigradum Doyère, 1840: The first integrative study of interpopulation variability in a tardigrade species. Journal of Zoological Systematics and Evolutionary Research, 57 (1), 1–23. https://doi.org/10.1111/jzs.12233
  140. Morgan, C.I. & King, P.E. (1976) British Tardigrades. Synopses of the British Fauna, New Series, 9, 1–133.
  141. Moreno-Talamantes, A., Roszkowska, M., García-Aranda, M.A., Flores-Maldonado, J.J. & Kaczmarek, Ł. (2019) Current knowledge on Mexican tardigrades with a description of Milnesium cassandrae sp. nov. (Eutardigrada: Milnesiidae) and discussion on the taxonomic value of dorsal pseudoplates in the genus Milnesium Doyère, 1840. Zootaxa, 4691 (5), 501–524. https://doi.org/10.11646/zootaxa.4691.5.5
  142. Møbjerg, N., Halberg, K.A., Jørgensen, A., Persson, D., Bjørn, M., Ramløv, H. & Kristensen, R.M. (2011) Survival in extreme environments–on the current knowledge of adaptations in tardigrades. Acta Physiologica, 202, 409–420. https://doi.org/10.1111/j.1748-1716.2011.02252.x
  143. Murray, J. (1907a) Some South African Tardigrada. Journal of the Royal Microscopical Society, 27 (5), 515–524. https://doi.org/10.1111/j.1365-2818.1907.tb01665.x
  144. Murray, J. (1907b) Scottish Tardigrada, collected by the lake survey. Transactions of the Royal Society of Edinburgh, 45 (3), 641–668. https://doi.org/10.1017/S0080456800011777
  145. Murray, J. (1910) Tardigrada. British Antarctic Expedition 1907–1909. Reports on the Scientific Investigations, 1 (Biology, Part V), 83–187.
  146. Murray, J. (1911a) Clare Island Survey. Arctiscoida. Proceedings of the Royal Irish Academy, 31 (37), 1–16.
  147. Murray, J. (1911b) Scottish Tardigrada. A review of our present knowledge. Annals of Scottish Natural History, 78, 88–95.
  148. Nelson, D.R., Bartels, P.J. & Guil, N. (2018) Tardigrade ecology. In: Schill, R.O. (Ed.), Water Bears: The Biology of Tardigrades. Zoological Monographs 2. Springer, Cham, pp. 163–210. https://doi.org/10.1007/978-3-319-95702-9_7
  149. Nelson, D.R. & Horning, D.S. (1979) Tardigrada of the Kowhai Bush, Kaikoura, New Zealand. Zeszyty Naukowe Uniwersytetu Jagiellońskiego, 529 (25), 125142.
  150. Nielsen, C. (1998) Origin and evolution of animal life cycles. Biological Reviews, 73 (2), 125–155. https://doi.org/10.1111/j.1469-185X.1997.tb00027.x
  151. Nguyen, L.-T., Schmidt, H.A., von Haeseler, A. & Minh, B.Q. (2015) IQ-TREE: a fast and effective stochastic algorithm for estimating maximum likelihood phylogenies. Molecular Biology and Evolution, 32 (1), 268–274. https://doi.org/10.1093/molbev/msu300
  152. Palmer, S.C. & Norton, R.A. (1992) Genetic diversity in thelytokous oribatid mites (Acari; Acariformes: Desmonomata). Biochemical Systematics and Ecology, 20 (3), 219–231. https://doi.org/10.1016/0305-1978(92)90056-J
  153. Pilato, G. (1972) Prime osservazioni sui tardigradi delle Isole Egadi. Bollettino delle sedute dell’Accademia Gioenia di Scienze naturale Catania, Serie IV, 11 (5–6), 111–124.
  154. Pilato, G. (1977) Variabilita’ in Echiniscus militaris Murray, 1911 (Heterotardigrada) e valore delle sue sottospecie. Animalia, 4 (1–2), 5–21.
  155. Pilato, G. & Binda, M.G. (2001) Biogeography and limnoterrestrial tardigrades: are they truly incompatible binomials? Zoologischer Anzeiger, 240 (3–4), 511–516. https://doi.org/10.1078/0044-5231-00061
  156. Pilato, G., Binda, M.G. & Lisi, O. (2005) Remarks on some Echiniscidae (Heterotardigrada) from New Zealand with the description of two new species. Zootaxa, 1027 (1), 27–45. https://doi.org/10.11646/zootaxa.1027.1.2
  157. Pilato, G., Fontoura, P., Lisi, O. & Beasley, C. (2008) New description of Echiniscus scabrospinosus Fontoura, 1982, and description of a new species of Echiniscus (Heterotardigrada) from China. Zootaxa, 1856 (1), 41–54. https://doi.org/10.11646/zootaxa.1856.1.4
  158. Plate, L. (1888) Beiträge zur Naturgeschichte der Tardigraden. Zoologische Jahrbücher, 3, 487–550. https://doi.org/10.5962/bhl.part.1265
  159. Pleijel, F., Jondelius, U., Norlinder, E., Nygren, A., Oxelman, B., Schander, C., Sundberg, P. & Thollesson, M. (2008) Phylogenies without roots? A plea for the use of vouchers in molecular phylogenetic studies. Molecular Phylogenetics and Evolution, 48 (1), 369–371. https://doi.org/10.1016/j.ympev.2008.03.024
  160. Rahm, G. (1925) Beitrag zur Kenntnis der Moostierwelt der preussischen Rheinlande. Archiv für Naturgeschichte, 90, 153–214.
  161. Rahm, G. (1928) Zur geographischen Verbreitung der Bärtierchen (Tardigraden) in der Schweiz (III. Mittlg.). Bulletin de la Société fribourgeoise des sciences naturelles, 1–7.
  162. Ramazzotti, G. (1945) I Tardigradi d’Italia. Memorie dell’Istituto Italiano di Idrobiologia, 2, 31–166.
  163. Ramazzotti, G. (1958) Echiniscus merokensis con spine sulla piastra scapolare e variabilita di questa specie, anche nei confronti di E. quadrispinosus f. cribrosa (Tardigrada). Atti della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale in Milano, 97 (1), 58–64.
  164. Ramazzotti, G. (1972) Il Phylum Tardigrada (Seconda edizione). Memorie dell’Istituto Italiano di Idrobiologia, 28, 1–732.
  165. Ramazzotti, G. & Maucci, W. (1982) A history of tardigrade taxonomy. In: Nelseon, D.R. (Ed.), Proceedings of the Third International Symposium on the Tardigrada, 1980. East Tennessee State University Press, Johnson City, Tennessee, pp. 11–30.
  166. Ramazzotti, G. & Maucci, W. (1983) Il Phylum Tardigrada. III edizione riveduta e aggiornata. Memorie dell’Istituto Italiano di Idrobiologia, 41, 1–1011.
  167. Rambaut, A., Suchard, M.A., Xie, D. & Drummond, A.J. (2014) Tracer. Version 1.6. Available from: https://beast.bio.ed.ac.uk/Tracer (accessed 31 July 2023)
  168. Richters, F. (1902) Neue Moosbewohner. Bericht über die Senckenbergische Naturforschende Gesselschaft in Frankfurt am Main, 23–26.
  169. Richters, F. (1903) Nordische Tardigraden. Zoologischer Anzeiger, 27 (5), 168–172.
  170. Richters, F. (1904a) Beitrag zur Verbreitung der Tardigraden im südlichen Skandinavien und an der mecklenburgischen Küste. Zoologischer Anzeiger, 28 (9), 347–352.
  171. Richters, F. (1904b) Arktische Tardigraden. Fauna Arctica, 3, 495–508.
  172. Richters, F. (1904c) Islandische Tardigraden. Zoologischer Anzeiger, 28 (10), 373–377.
  173. Rocha, A.M., González-Reyes, A., Corronca, J., Rodríguez-Artigas, S., Doma, I., Repp, E.Y. & Acosta, X. (2016) Tardigrade diversity: an evaluation of natural and disturbed environments of the province of Salta (Argentina). Zoological Journal of the Linnean Society, 178 (4), 755–764. https://doi.org/10.1111/zoj.12476
  174. Ronquist, F. & Huelsenbeck, J.P. (2003) MrBayes 3: Bayesian phylogenetic inference under mixed models. Bioinformatics, 19 (12), 1572–1574. https://doi.org/10.1093/bioinformatics/btg180
  175. Roszkowska, M., Grobys, D., Zawierucha, K., Kmita, H. & Kaczmarek, Ł. (2018) Clarification of taxonomic status and geographic distribution of Echiniscus merokensis Richters, 1904 sensu lato in the light of integrative taxonomy. Abstract Book of the 14th International Symposium on Tardigrada, Copenhagen, 30 July–3 August, 79.
  176. Rudescu, L. (1964) Tardigrada. Fauna Republicii Populare Romîne, 4 (7), 1–308.
  177. Santos, E., Veiga, P., Rubal, M., Bartels, P.J., da Rocha, C.M.C. & Fontoura, P. (2019) Batillipes pennaki Marcus, 1946 (Arthrotardigrada: Batillipedidae): deciphering a species complex. Zootaxa, 4648 (3), 549–567. https://doi.org/10.11646/zootaxa.4648.3.9
  178. Schaudinn, F. (1901) Die Tardigraden. Fauna Arctica, 2, 186–196.
  179. Schultze, C.A.S. (1840) Echiniscus Bellermanni, Animal Crustaceum, Macrobioto Hufelandii Affine. Apud G. Reimer, Berlin, 8 pp.
  180. Schultze, C.A.S. (1861) Echiniscus Creplini, Animalculum e Familia Arctiscoidum. Gryphiae, F.G., Kunike, 12 pp.
  181. Schultze, M. (1865) Echiniscus sigismundi, ein Arctiscoide der Nordsee. Archiv für mikroskopische Anatomie, 1, 428–436. https://doi.org/10.1007/BF02961427
  182. Scourfield, D.J. (1897) Contributions to the non-marine fauna of Spitsbergen. Part I. Preliminary notes, and reports on the Rhizopoda, Tardigrada, Entomostraca etc. Proceedings of the Zoological Society of London, 65 (3), 784–792. https://doi.org/10.1111/j.1096-3642.1897.tb03120.x
  183. Séméria, Y. (1982) Recherches sur la faune urbaine et suburbaine des tardigrades muscicoles et lichenicoles. II. L’espace sub-urbain: les hauteurs orientales de Nice-Ville. Extrait du Bulletin Mensuel de la Société Linnéenne de Lyon, 51 (10), 315–328. https://doi.org/10.3406/linly.1982.10562
  184. Smith, F.W., Bartels, P.J. & Goldstein, B. (2017) A hypothesis for the composition of the tardigrade brain and its implications for panarthropod brain evolution. Integrative and Comparative Biology, 57 (3), 546–559. https://doi.org/10.1093/icb/icx081
  185. Stec, D., Kristensen, R.M. & Michalczyk, Ł. (2020) An integrative description of Minibiotus ioculator sp. nov. from the Republic of South Africa with notes on Minibiotus pentannulatus Londoño et al., 2017 (Tardigrada: Macrobiotidae). Zoologischer Anzeiger, 286, 117–134. https://doi.org/10.1016/j.jcz.2020.03.007
  186. Suzuki, A.C. (2008) Appearance of males in a thelytokous strain of Milnesium cf. tardigradum (Tardigrada). Zoological Science, 25 (8), 849–853. https://doi.org/10.2108/zsj.25.849
  187. Suzuki, A.C. (2017) Chapter 10. Tardigrade research in Japan. In: Motokawa, M. & Kajihara, H. (Eds), Diversity and Commonality in Animals. Springer, Tokyo, pp. 267–284. https://doi.org/10.1007/978-4-431-56432-4_10
  188. Thulin, G. (1911) Beiträge zur Kenntnis der Tardigradenfauna Schwedens. Arkiv för zoologi, 7, 1–60. https://doi.org/10.5962/bhl.part.1270
  189. Thulin, G. (1928) Über die Phylogenie und das System der Tardigraden. Hereditas, 11 (2–3), 207–266. https://doi.org/10.1111/j.1601-5223.1928.tb02488.x
  190. Trifinopoulos, J., Nguyen, L.-T., von Haeseler, A. & Minh, B.Q. (2016) W-IQ-TREE: a fast online phylogenetic tool for maximum likelihood analysis. Nucleic Acids Research, 44 (W1), 232–235. https://doi.org/10.1093/nar/gkw256
  191. Vaidya, G., Lohman, D.J. & Meier, R. (2011) SequenceMatrix: concatenation software for the fast assembly of multi-gene datasets with character set and codon information. Cladistics, 27 (2), 171–180. https://doi.org/10.1111/j.1096-0031.2010.00329.x