[organisms] see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   Domain Bacteria Woese et al. 1990
     Phylum "Proteobacteria" Garrity et al. 2005 see Superphylum Proteobacteria Craig et al. 2010
       Class Alphaproteobacteria Garrity et al. 2006
         Order Rhodospirillales Pfennig and Trüper 1971 (Approved Lists 1980)
           Family Rhodospirillaceae Pfennig and Trüper 1971 (Approved Lists 1980)
             Genus Azospirillum Tarrand et al. 1979 (Approved Lists 1980)
               1 Azospirillum lipoferum (Beijerinck 1925) Tarrand et al. 1979 (Approved Lists 1980)
               2 Azospirillum amazonense Magalhães et al. 1984
               3 Azospirillum brasilense corrig. Tarrand et al. 1979 (Approved Lists 1980)
               4 Azospirillum doebereinerae Eckert et al. 2001
               5 Azospirillum halopraeferens Reinhold et al. 1987
               6 Azospirillum irakense Khammas et al. 1991 see Niveispirillum irakense (Khammas et al. 1991) Lin et al. 2014
               7 Azospirillum largimobile corrig. (Skerman et al. 1983) Ben Dekhil et al. 1997
               8 Azospirillum melinis Peng et al. 2006
               9 Azospirillum oryzae Xie and Yokota 2005