[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 Betaproteobacteria Garrity et al. 2006
         Order Neisseriales Tønjum 2006
           Family Neisseriaceae Prévot 1933 (Approved Lists 1980)
             Genus Aquaspirillum Hylemon et al. 1973 (Approved Lists 1980)
               1 [Aquaspirillum serpens] (Müller 1786) Hylemon et al. 1973 (Approved Lists 1980)
               2 Aquaspirillum arcticum Butler et al. 1990
               3 [Aquaspirillum itersonii] (Giesberger 1936) Hylemon et al. 1973 (Approved Lists 1980) see Novispirillum itersonii (Giesberger 1936) Yoon et al. 2007
               4 [Aquaspirillum peregrinum] (Pretorius 1963) Hylemon et al. 1973 (Approved Lists 1980) see Insolitispirillum peregrinum (Pretorius 1963) Yoon et al. 2007
               5 Aquaspirillum polymorphum (Williams and Rittenberg 1957) Hylemon et al. 1973 (Approved Lists 1980)
               6 Aquaspirillum putridiconchylium (Terasaki 1961) Hylemon et al. 1973 (Approved Lists 1980)