Gordioida is een klasse van paardenhaarwormen (Nematomorpha). De soorten in deze klasse zijn gerelateerd aan hun voorkomen in of nabij zoet water. In Nederland komt één soort voor, de Gordius setiger.
Taxonomie Orde Chordodea Familie Chordodidae Geslacht Chordodes Chordodes aelianus - (Camerano, 1894) (1894) Viaggio del Dottor Alfredo Borelli nella Repubblica Argentina e nel Paraguay. Gordii. Bollettino dei Musei di Zoologia ed anatomia comparata della R. Universita di Torino 9, 1-6 Chordodes aethiopicus - Inoue, 1974 (1974) A new species of the Genus Chordodes (Gordiacea) from Ethiopia. Annotationes Zoologicae Japonenses 47, 107-109 Chordodes africanus - Sciacchitano, 1933 Chordodes albibarbatus - Montgomery, 1898 Chordodes ambonensis - Sciacchitano, 1962 Chordodes anthophorus - Kirjanova, 1950 Chordodes auranthiacus - von Linstow, 1906 Chordodes balzani - Camerano, 1896 Chordodes baramensis - Römer, 1895 Chordodes betularius - Linstow, 1904 Chordodes bipilus - Kirjanova, 1957 Chordodes boulengeri - Camerano, 1912 Chordodes bouvieri - (Villot, 1885) Römer, 1859 Chordodes brasiliensis - Janda, 1894 Chordodes brevipilus - Schmidt-Rhaesa, 2002 Chordodes bukavuensis - Sciacchitano, 1958 Chordodes caledoniensis - (Villot, 1874) Römer, 1896 Chordodes capensis - Camerano, 1859 Chordodes capillatus - Linstow, 1901 Chordodes carmelitanus - Carvalho and Feio, 1950 Chordodes clavatus - Linstow, 1906 Chordodes compactus - Schmidt-Rhaesa and Brune, 2008 Chordodes compressus - Römer, 1895 Chordodes congolensis - Sciacchitano, 1933 Chordodes corderoi - Carvalho, 1946 Chordodes cornuta - Villalobos and Camino, 1999 Chordodes cubanensis - Montgomery, 1898 Chordodes curvicillatus - Kirjanova and Spiridonov, 1980 Chordodes defilippii - (Rosa, 1880) Römer, 1895 Chordodes devius - Kirjanova, 1950 Chordodes digitatus - Linstow, 1901 Chordodes ferox - Camerano, 1897 Chordodes festae - Camerano, 1897 Chordodes fukuii - Inoue, 1951 Chordodes furnessi - Montgomery, 1898 Chordodes gariazzi - Camerano, 1902 Chordodes gestri - Camerano, 1904 Chordodes guineensis - Spiridonov, 2002 Chordodes hawkeri - Camerano, 1902 Chordodes heinzei - Sciacchitano, 1937 Chordodes ikelensis - Sciacchitano, 1961 Chordodes insidiator - Camerano, 1899 Chordodes iturensis - Sciacchitano, 1958 Chordodes jandae - Camerano, 1895 Chordodes japonensis - Inoue, 1952 Chordodes joyeuxi - Dorier, 1935 Chordodes kakandensis - Sciacchitano, 1958 Chordodes kallstenii - Jagerskiöld, 1897 Chordodes kivuensis - Sciacchitano, 1958 Chordodes kolensis - Sciacchitano, 1933 Chordodes koreensis - Baek, 1993 Chordodes lefeburi - (Sciacchitano, 1937) Chordodes lenti - Carvalho, 1944 Chordodes ligasiensis - Sciacchitano, 1933 Chordodes lotus - de Villalobos and de Miralles, 1997 Chordodes maculatus - Sciacchitano, 1958 Chordodes madagascariensis - Camerano, 1897 Chordodes matensis - de Villalobos and de Miralles, 1997 Chordodes mobensis - Sciacchitano, 1958 Chordodes modiglianii - (Camerano, 1892) Camerano, 1897 Chordodes montgomeryi - Camerano, 1901 Chordodes moraisi - (Carvalho, 1942) Carvalho, 1944 Chordodes morgani - Montgomery, 1898 Chordodes moutoni - Camerano, 1895 Chordodes muelleri - Sciacchitano, 1937 Chordodes nobilii - Camerano, 1901 Chordodes ornatus - (Grenacher, 1868) Chordodes parasitus - Creplin, 1847 Chordodes penicillatus - Camerano, 1895 Chordodes peraccae - (Camerano, 1894) Chordodes pilosus - Möbius, 1855 Chordodes pollonerae - Camerano, 1912 Chordodes polycoronatus - Schmidt-Rhaesa and Brune, 2008 Chordodes polytuberculatus - Schmidt-Rhaesa and Menzel, 2005 Chordodes puncticulatus - Camerano, 1895 Chordodes queenslandi - Schmidt-Rhaesa, 2002 Chordodes rigatus - Sciacchitano, 1937 Chordodes ruandensis - Sciacchitano, 1937 Chordodes sajanensis - Spiridonov, 2000 Chordodes sandoensis - Sciacchitano, 1937 Chordodes schoutedeni - Sciacchitano, 1933 Chordodes shipleyi - Camerano, 1899 Chordodes siamensis - Camerano, 1903 Chordodes silvestri - Camerano, 1895 Chordodes skorikovi - Camerano, 1903 Chordodes staviarskii - Carvalho and Feio, 1950 Chordodes tenodarae - Kirjanova, 1957 Chordodes timorensis - Camerano, 1895 Chordodes tuberculatus - Linstow, 1901 Chordodes villalobi - Schmidt-Rhaesa and Brune, 2008 Chordodes wangi - Wu and Tang, 1933 Geslacht Euchordodes Euchordodes libellulovivens - Heinze, 1937 Euchordodes malaysiensis - Inoue, 1966 Euchordodes nigromaculatus - Poinar, 1991 Geslacht Neochordodes Neochordodes australis - de Miralles and de Villalobos, 1996 Neochordodes bonaerensis - de Miralles and de Villalobos, 1998 Neochordodes californensis - de Miralles and de Villalobos, 1995 Neochordodes chordodides - Schmidt-Rhaesa and Menzel, 2005 Neochordodes columbianus - Faust and Ramos, 1960 Neochordodes occidentalis - (Montgomery, 1898) Poinar and Doleman, 1974 Neochordodes nietoi - De Miralles and De Villalobos, 1994 Neochordodes occidentalis - (Montgomery, 1898) Neochordodes punctatus - De Miralles and De Villalobos, 1996 Neochordodes semiluna - Villalobos and Camino, 1999 Neochordodes serranensis - De Miralles and De Villalobos, 1996 Neochordodes torrenticola - De Miralles and De Villalobos, 1996 Neochordodes uniareolatus - Carvalho, 1946 Geslacht Pantachordodes Pantachordodes europaeus - (Heinze, 1952) Geslacht Pseudochordodes Pseudochordodes bedriagae - (Camerano, 1896) Pseudochordodes bulbareolatus - Schmidt-Rhaesa and Menzel, 2005 Pseudochordodes dugesi - (Camerano, 1898) Pseudochordodes gordioides - (Montgomery, 1898) de Miralles et al., 1997 Pseudochordodes griffini - (Camerano, 1898) Pseudochordodes guatemalensis - De Miralles et al., 1997 Pseudochordodes manteri - Carvalho, 1942 Pseudochordodes meridionalis - Carvalho and Feio, 1950 Pseudochordodes pardalis - (Camerano, 1893) Pseudochordodes texanus - Schmidt-Rhaesa et al., 2003 Familie Parachordodidae Geslacht Beatogordius Beatogordius abaiconus - Carvalho, 1946 Beatogordius abbreviatus - (Villot, 1874) de Miralles, 1984 Beatogordius alfredi - (Camerano, 1894) Beatogordius australiensis - Schmidt-Rhaesa and Bryant, 2004 Beatogordius brieni - Sciacchitano, 1961 Beatogordius deshayesi - (Villot, 1874) Beatogordius echinatus - (Linstow, 1901) Schmidt-Rhaesa and de Villalobos, 2001 Beatogordius erythraeus - (Camerano, 1915) Sciacchitano, 1940 Beatogordius funis - de Villalobos et al., 2003 Beatogordius inesae - (Cavalieri, 1961) Miralles, 1984 Beatogordius irregularis - Miralles, 1972 Beatogordius latastei - (Camerano, 1895) Heinze, 1934 Beatogordius lineatus - Schmidt-Rhaesa and Bryant, 2004 Beatogordius palustre - de Villalobos et al., 2003 Beatogordius raphaelis - (Camerano, 1893) Sciacchitano, 1937 Beatogordius regularis - Heinze, 1934 Beatogordius sankurensis - Sciacchitano, 1958 Beatogordius ugandensis - Schmidt-Rhaesa and de Villalobos, 2001 Beatogordius variabilis - Miralles, 1981 Beatogordius wilsoni - Sciacchitano, 1958 Geslacht Gordionus Gordionus alascensis - (Montgomery, 1907) Schmidt-Rhaesa et al., 2003 Gordionus alpestris - (Villot, 1885) Heinze, 1937 Gordionus annamensis - Spiridonov, 1993 Gordionus austriacus - Heinze, 1952 Gordionus austrinus - de Villalobos, Zanca and Ibarra-Vidal, 2005 Gordionus barbatus - Schmidt-Rhaesa and Cieslak, 2008 Gordionus bilinareolatus - (Heinze, 1937) Heinze 1941 Gordionus blanchardi - (Villot, 1874) Gordionus brunneus - Monten, 1951 Gordionus capitosulcatus - (Montgomery, 1898) Heinze, 1935 Gordionus chinensis - (Villot, 1874) Gordionus conglomeratus - Heinze, 1952 Gordionus cyrnensis - Giudicelli and Nicoli, 1962 Gordionus densareolatus - (Montgomery, 1898) Gordionus diligens - de Villalobos et al., 1999 Gordionus divergens - Schuurmanns Steckhoven, 1943 Gordionus dubiosus - Henze, 1937 Gordionus enigmaticus - de Villalobos, Zanca and Ibarra-Vidal, 2005 Gordionus formidatus - Havlik, 1954 Gordionus fragmentarius - Heinze, 1952 Gordionus harpali - Heinze, 1940 Gordionus kaschgaricus - (Camerano, 1897) Heinze, 1935 Gordionus kii - Schmidt-Rhaesa and Sato, 2009 Gordionus lapponicus - Monten, 1951 Gordionus lenae - Heinze, 1937 Gordionus lineatus - (Leidy, 1851) Schmidt-Rhaesa et al., 2003 Gordionus linourgos - de Villalobos et al., 1999 Gordionus longareolatus - (Montgomery, 1898) Schmidt-Rhaesa et al., 2003 Gordionus longistriatus - Schmidt-Rhaesa, 2004 Gordionus lunatus - Müller, 1927 Gordionus meissneri - Müller, 1927 Gordionus molopsis - Heinze, 1937 Gordionus ondulatus - Miralles, 1984 Gordionus perronciti - (Camerano, 1887) Gordionus platycephalus - (Montgomery, 1898) Heinze, 1935 Gordionus porosus - de Villalobos and Voglino, 2000 Gordionus preslii - (Vejdovsky, 1886) (1886) Zur Morphologie der Gordiiden. Zeitschrift für wissenschaftliche Zoologie 43, 369-433 Gordionus prismaticus - (Villot, 1874) Heinze, 1935 Gordionus punctulatus - Heinze, 1937 Gordionus reticulates - (Villot, 1874) Gordionus roccatii - (Camerano, 1912) Heinze, 1935 Gordionus rugosus - Canadjija, 1956 Gordionus scaber - Müller, 1927 Gordionus scripturus - Heinze, 1952 Gordionus semistiatus - Heinze, 1937 Gordionus senkovi - Malakhov and Spiridonov, 1982 Gordionus silphae - Heinze, 1937 Gordionus sinepilosus - Schmidt-Rhaesa et al., 2003 Gordionus stenobothri - Canadjija, 1956 Gordionus strigatus - Müller, 1927 Gordionus subalpinus - Heinze, 1952 Gordionus sulcatus - Heinze, 1937 Gordionus thiemanni - Heinze, 1937 Gordionus thuringensis - Müller, 1927 Gordionus turkensis - Schmidt-Rhaesa and Cieslak, 2008 Gordionus violaceus - (Baird, 1853) Müller, 1927 Gordionus wolterstorffii - (Camerano, 1888) Heinze, 1937 Geslacht Parachordodes Parachordodes aequatorialis - Sciacchitano, 1937 Parachordodes annulatus - Linstow, 1906 Parachordodes arndti - Heinze, 1935 Parachordodes bourguignoni - Sciacchitano, 1937 Parachordodes capitosulcatus - (Montgomery, 1898) Heinze, 1935 Parachordodes ciferrii - Sciacchitano, 1932 Parachordodes coreanus - Linstow, 1906 Parachordodes densareolatus - (Montgomery, 1898) Camerano, 1915 Parachordodes diblastus - (Örley, 1881) Schmidt-Rhaesa, 2008 Parachordodes gemmatus - (Villot, 1885) Camerano, 1897 Parachordodes lestici - Heinze, 1935 Parachordodes maculatus - A (Linstow, 1883) Linstow, 1905 Parachordodes magnus - Spiridonov, 1989 Parachordodes megareolatus - Schmidt-Rhaesa, Chung Parachordodes modestus - Spiridonov, 1989 Parachordodes okadai - Inoue, 1955 Parachordodes orientalis - Fukui and Inoué, 1940 Parachordodes pleskei - (Camerano, 1986) Parachordodes propareolatus - Heinze, 1935 Parachordodes pustulosus - (Baird, 1853) Camerano, 1897 Parachordodes sciacchitanoi - Heinze, 1935 Parachordodes sjöstedti - Camerano, 1910 Parachordodes speciosus - (Janda, 1894) Heinze, 1935 Parachordodes tegonotus - Poinar et al., 2004 Parachordodes tolosanus - (Dujardin, 1842) Camerano, 1897 Geslacht Paragordionus Paragordionus bohemicus - Havlik, 1947 Paragordionus dispar - (Müller, 1927) Heinze, 1935 Paragordionus ibericus - Schmidt-Rhaesa and Cieslak, 2008 Paragordionus kawamurai - Yamaguti, 1943 Paragordionus rautheri - Heinze, 1937 Paragordionus vejdovskyi - (Janda, 1895) Heinze, 1935 Geslacht Semigordionus Semigordionus circumannulatus - Heinze, 1952 Familie Paragordiidae Geslacht Paragordius Paragordius andreasii - Zanca and de Villalobos, 2006 Paragordius areolatus - Linstow, 1906 Paragordius aurantiacus - Linstow, 1906 Paragordius cinctus - Linstow, 1906 Paragordius dartevellei - Sciacchitano, 1958 Paragordius diversolobatus - Heinze, 1935 Paragordius emeryi - (Camerano, 1895) Camerano, 1895 Paragordius esavianus - Carvalho, 1942 Paragordius flavescens - Linstow, 1906