Rhizobiales Kuykendall 2006 Rhizobiales Kuykendall 2006 Rhizobium Frank 1889 (Approved Lists 1980) emend. Young et al. 2001 Universal Root Woese et al. 1990 Bacteria (None 2015) Woese et al. 1990 Proteobacteria (sic) Garrity et al. 2021 Pseudomonadota corrig. Garrity et al. 2021 Alphaproteobacteriota (sic) Garrity et al. 2021 Alphaproteobacteria Garrity et al. 2006 Rhizobiales Kuykendall 2006 Alphaproteobacteria Garrity et al. 2006 Parvularculales Garrity et al. 2003 Kordiimonadales Kwon et al. 2005 emend. Hördt et al. 2020 Rhodospirillales Pfennig and Trüper 1971 (Approved Lists 1980) emend. Hördt et al. 2020 Rickettsiales Gieszczykiewicz 1939 (Approved Lists 1980) emend. Dumler et al. 2001 Rhodobacterales Garrity et al. 2006 emend. Hördt et al. 2020 Sphingomonadales Yabuuchi and Kosako 2006 emend. Hördt et al. 2020 Caulobacterales Henrici and Johnson 1935 (Approved Lists 1980) Sneathiellales Kurahashi et al. 2008 Kiloniellales Wiese et al. 2009 Hyphomicrobiales Douglas 1957 (Approved Lists 1980) emend. Hördt et al. 2020 Incertae sedis 23 None 2015 Magnetococcales Bazylinski et al. 2013 Incertae sedis 91 None 2015 Incertae sedis 136 None 2015 Incertae sedis 154 None 2015 Incertae sedis 120 Tirandaz et al. 2015 Iodidimonadales Iino et al. 2016 Emcibacterales Iino et al. 2016 Micropepsales Harbison et al. 2017 Rhodothalassiales Venkata Ramana et al. 2014 Incertae sedis 70 None 2015 Incertae sedis 224 Kragelund et al. 2006 Incertae sedis 221 Kragelund et al. 2006 Incertae sedis 263 Kwan et al. 2012 Incertae sedis 265 Anderson and Haygood 2007 Incertae sedis 275 Bing et al. 2013 Incertae sedis 326 Horn et al. 1999 Pelagibacterales Grote et al. 2012 Minwuiales Sun et al. 2018 Holosporales Szokoli et al. 2020 Hyphomonadales Kevbrin et al. 2021 Maricaulales Kevbrin et al. 2021 Methylospongiales Podell et al. 2020 Incertae sedis 667 Kanamori et al. 2002 Rhizobiaceae Conn 1938 (Approved Lists 1980) emend. Hördt et al. 2020 Bradyrhizobiaceae Garrity et al. 2006 Aurantimonadaceae Hördt et al. 2020 Hyphomicrobiaceae Babudieri 1950 (Approved Lists 1980) emend. Hördt et al. 2020 Beijerinckiaceae Garrity et al. 2006 emend. Hördt et al. 2020 Rhodobiaceae Garrity et al. 2006 emend. Hördt et al. 2020 Xanthobacteraceae Lee et al. 2005 emend. Hördt et al. 2020 Cohaesibacteraceae Hwang and Cho 2008 emend. Hördt et al. 2020 Incertae sedis 114 Doronina et al. 2013 Incertae sedis 135 None 2015 Roseiarcaceae Kulichevskaya et al. 2014 emend. Hördt et al. 2020 Incertae sedis 169 None 2015 Incertae sedis 183 None 2015 Chelatococcaceae Dedysh et al. 2016 Phyllobacteriaceae Mergaert and Swings 2006 emend. Hördt et al. 2020 Bartonellaceae Gieszczykiewicz 1939 (Approved Lists 1980) emend. Brenner et al. 1993 Methylocystaceae Bowman 2006 emend. Hördt et al. 2020 Brucellaceae Breed et al. 1957 (Approved Lists 1980) Methylobacteriaceae Garrity et al. 2006 emend. Hördt et al. 2020 Meganemaceae McIlroy et al. 2015 Notoacmeibacteraceae Huang et al. 2017 emend. Hördt et al. 2020 Mabikibacteraceae Choi et al. 2017 Incertae sedis 103 None 2015 Incertae sedis 160 None 2015 Incertae sedis 182 None 2015 Incertae sedis 201 Chen et al. 2017 Incertae sedis 210 None 2015 Salinarimonadaceae Cole et al. 2018 Ancalomicrobiaceae Dahal et al. 2018 emend. Felföldi et al. 2019 Incertae sedis 286 McCutcheon et al. 2009 Alsobacteraceae Sun et al. 2018 Aestuariivirgaceae Li et al. 2019 Phaeomarinibacteraceae corrig. Dittami et al. 2014 Phaeomarinobacteraceae (sic) Dittami et al. 2014 Acuticoccaceae Lai et al. 2019 Incertae sedis 518 Dong et al. 2019 Lichenihabitantaceae Noh et al. 2019 Segnochrobactraceae Akter et al. 2020 Incertae sedis 134 Takeuchi et al. 2014 Lichenibacteriaceae Pankratov et al. 2020 Rhabdaerophilaceae Ming et al. 2020 Incertae sedis 695 Neuvonen et al. 2016 Dedysh S.N. Haupt E.S. Dunfield P.F. 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Microbio. 1664-302X 10.3389/fmicb.2020.00468 32373076 According to Rule 51b(1), the order name Rhizobiales Kuykendall 2006 is illegitimate because it contains the genus Hyphomicrobium Stutzer and Hartleb 1899 (Approved Lists 1980), which is the type of the order Hyphomicrobiales Douglas 1957 (Approved Lists 1980).