Species (22.489)
- Rhinozeta triciliata Van Hoven, Gilchrist & Hamilton-Attwell 1988
- Rhinozeta rhinozeta Van Hoven, Gilchrist & Hamilton-Attwell 1988
- Rhinozeta unilaminatus Van Hoven, Gilchrist & Hamilton-Attwell 1988
- Rhizobranchium morchellii Jankowski 1981
- Rhipidostoma uncinatum Cunha & Muniz 1925
- Rhizocaryum concovum Caullery & Mesnil 1907
- Rhizochona armata Jankowski 1973
- Rhizodomus tagatzi Strelkow & Virketis 1950
- Rhizotricha beckeri Hsiung 1930
- Rhopalophrya cirrifera Penard 1922
- Rhopalophrya gracilis Kahl 1926
- Rhopalophrya pentacerca Grandori & Grandori 1934
- Rhopalophrya salina Kirby 1932
- Rhopalophrya pilosa Penard 1922
- Rhynchodinium paradocum Cunha & Penido 1927
- Rhynchophria palpaus Collin 1909
- Rhopalophrya sulcata Kahl 1930
- Rhynchophrya cristallina Raabe 1935
- Riboscyphidia scorpaenae Fabre ()
- Rimaleptus amphileptoides Kahl 1931
- Rimacineta falcata Jankowski 1981
- Rigchostoma membranata Vuxanovici 1963
- Rimaleptus binucleatus Kahl 1931
- Rimostrombidium armeniensis Zharikov 1987
- Rimostrombidium glacicolum Petz, Song & Wilbert 1995
- Rimostrombidium brachykinetum Krainer 1995
- Rimostrombidium lacustris Foissner, Skogstad & Pratt 1988
- Rimostrombidium humile Penard 1922
- Rostrophrya camerounensis Njine 1979
- Rostrophrya regis Njine 1979
- Rostrophrya terricola Foissner 1993
- Rostrophryides australis Blatterer & Foissner 1988
- Rostrophryides africana Foissner 1987
- Roviniella spheromae Matthes 1972
- Ptychostomum campelomae Kozloff 1960
- Ptychocylis wailesi Kofoid & Campbell 1929
- Puytoracia kozloffi Puytorac 1968
- Pyxidium asymmetricum Biczok 1956
- Pyxidium bosminae Kahl 1935
- Pyxidium collare Kahl 1935
- Pyxidium cothurnioides Kent 1881
- Pyxidium canthocampti Penard 1922
- Pyxidium curvicaule Penard 1922
- Pyxidium hebes Kellicott 1888
- Pyxidium fabrei Faure-Fremiet 1905
- Pyxidium henneguyi Faure-Fremiet 1905
- Pyxidium invaginatum Kahl 1935 ssp. muscorum
- Pyxidium nutans Stokes 1889
- Pyxidium tardigradum Van der Land 1964
- Pyxidium longicollum Biegel 1954
- Pyxidium urecolatum Stokes 1886
- Pyxidium vernale Stokes 1887
- Quasillagilis constanciensis Busch 1920
- Raabella helensis Chatton & Lwoff 1950
- Raabellocineta elongata Puytorac, Groliere & Grain 1979
- Radiophrya enchytraei Meier 1954
- Radiophrya limnodili Cheissin 1930
- Radiophrya naidos Schmidt 1846
- Radiophrya ochridiana Puytorac 1959
- Radiophrya olivieri Puytorac 1954
- Radiophrya pachydrili Claparède 1861
- Radiophrya pungens Stein 1861
- Radiophrya prolifera Claparède & Lachmann? 1859
- Radiophrya peloscolecis Heidenreich 1935
- Radiophrya sagittata Meier 1954
- Radiophryoides komarecki Lom 1956
- Radiophryoides aclosomatis Anderson 1888
- Radiophrya tubificis Katashima 1952
- Ptyxidium ovulum Perty 1852
- Pusilloburius labiatus Corliss 1979
- Puytoraciella dibryophrys Njine 1979
- Pygmotheroides njinei Affa'a 1979
- Pycnothrix monocystoides Schubotz 1909
- Pyxicola affinis Kent 1882
- Pyxicola annulata Leidy 1882
- Pyxicola carteri Kent 1882
- Pyxicola constricta Stokes 1884
- Pyxicola ligiae Cuenot 1811
- Pyxicola furcifer Kent 1882
- Pyxicola entzi Stiller 1931
- Pyxicola limbata Stiller 1922
- Pyxicola operculigera Kent 1882
- Pyxicola pyxidiformis D'Udekem 1862
- Pyxicola socialis Gruber 1879
- Pyxidiella cothurnoides Corliss 1960
- Pyxidium acaule Kahl 1935
- Pyxicola striata Kellicott 1884
- Pyxidium arboricola Biegel 1954
- Pyxidium aselli Penard 1922
- Raabena bella Wolska 1967
- Radiophrya deronis Heidenreich 1935
- Radiophrya biacuta Puytorac 1954
- Pseudoglaucoma muscorum Kahl 1931
- Pseudoglaucoma thermalis Kahan & Lasman 1966
- Pseudoglaucoma thermale Kahan & Lasman 1966
- Pseudokeronopsis pulchra Borror & Wicklow 1983
- Pseudokeronopsis rubra Ehrenberg 1838
- Pseudokreyella australis Foissner 1993
- Pseudokreyella terricola Foissner 1985
- Pseudoplatyophrya terricola Foissner 1985