Ra
- Radopholus
- Raphidascaroides
Rh
- Rhabdiasidae
- Rhabditida
- Rhabditidae
- Rhabditis
- Rhabditoides
- Rhabditolaimus
- Rhabditophanes
- Rhabdochona
- Rhabdocoma
- Rhabdodemania
- Rhabdodemaniidae
- Rhabdolaimidae
- Rhabdolaimus
- Rhabdontolaimus
- Rhadinaphelenchus
- Rhadinema
- Rhaphidascaris
- Rhigonematidae
- Rhinema
- Rhinonema
- Rhips
- Rhitis
- Rhodolaimus
- Rhynchonema
Ri
- Richtersia
- Richtersiidae
- Rinadia
- Ritenbenkia
Ro
Robbea Gerlach, 1956
- Robbea caelestris Gerlach, 1956
- Robbea tenax Gerlach, 1963
Nematoda → Chromadorea → Desmodorida → Desmodoridae
- Robertdollfusidae
- Robertia
- Robertiidae
- Rogerus
Rotylenchoidinae Whitehead, 1958
- genus Antarctylus Sher, 1973
- genus Calvatylus Jairajpuri & Siddiqi, 1977
- genus Helicotylenchus Steiner, 1945
- genus Orientylus Jairajpuri & Siddiqi, 1977
- genus Plesiorotylenchus Vivlas et al., 1993
- genus Rotylenchoides Whitehead, 1958
- genus Rotylenchus Filipjev, 1936
- genus Varotylus Siddiqi, 1986
Nematoda → Secernentea → Tylenchida → Hoplolaimidae → Rotylenchoidinae
Rotylenchoides Whitehead, 1958
- Rotylenchoides affinis Luc, 1960
- Rotylenchoides brevis Whitehead, 1958
- Rotylenchoides intermedius Luc, 1960
Nematoda → Secernentea → Tylenchida → Hoplolaimidae → Rotylenchoidinae
Rotylenchus Filipjev, 1934
- Rotylenchus agnetis Szczygiel, 1968
- Rotylenchus aquaticus Germani & Scotto la Massese, 2002
- Rotylenchus ascalpi Scotto la Massese & Germani, 2001
- Rotylenchus blothrotylus (Baldwin & Bell, 1981)
- Rotylenchus breviglans Sher, 1965
- Rotylenchus buxophilus Golden, 1956
- Rotylenchus capensis Van den Berg & Heyns, 1974
- Rotylenchus capitatus Eroshenko, 1981
- Rotylenchus catharinae Van den Berg & Heyns, 1974
- Rotylenchus cazorlaensis Castillo & Gomez, 1989
- Rotylenchus colbrani Brzeski & Choi, 1998
- Rotylenchus corsicus Scotto la Massese & Germani, 2001
- Rotylenchus cypriensis Antoniou, 1981
- Rotylenchus echelimae Scotto la Massese & Germani, 2001
- Rotylenchus eximius Siddiqi, 1964
- Rotylenchus goodeyi Loof & Oostenbrink, 1958
- Rotylenchus gracilidens (Sauer, 1958)
- Rotylenchus graecus Vovlas & Troccoli, 1996
- Rotylenchus helenae Germani & Scotto la Massese, 2002
- Rotylenchus hopperi (Baldwin & Bell, 1984)
- Rotylenchus incognitus Germani & Scotto la Massese, 2002
- Rotylenchus incultus Sher, 1965
- Rotylenchus jagatpurensis Sultan, 1985
- Rotylenchus landii Germani & Scotto la Massese, 2002
- Rotylenchus laurentinus Scognamiglio & Talamè, 1973
- Rotylenchus lobatus Sultan, 1985
- Rotylenchus magnus Zancada, 1986
- Rotylenchus mesorobustus Zancada, 1986
- Rotylenchus multicinctus Cobb
- Rotylenchus ouensensis Boag & Hooper, 1981
- Rotylenchus pararobustus Schuurmans Stekhoven & Teunissen
- Rotylenchus provincialis Scotto la Massese & Germani, 2001
- Rotylenchus pumilus (Perry, 1959)
- Rotylenchus quartus (Andrássy, 1958)
- Rotylenchus robustus (de Man, 1876)
- Rotylenchus rugatocuticulatus Sher, 1965
- Rotylenchus sabarlyi Scotto la Massese & Germani, 1998
- Rotylenchus troncapitatus Scotto la Massese & Germani, 1998
- Rotylenchus uniformis (Thorne)
- Rotylenchus unisexus Sher, 1965
Nematoda → Secernentea → Tylenchida → Hoplolaimidae → Rotylenchoidinae
Ru
- Ruamowhitia
- Rugopharynx