Acanthopodina unifies all amoebae capable to produce acanthopodia (family Acanthamoebidae). It also includes the parasitic amoeba Balamuthia mandrillaris, a large Stereomyxa-like amoeba which was initially classified as a leptomyxid (Visvesvara et al. 1993), but consistently groups with Acanthamoeba in molecular trees (Amaral Zettler et al. 2000; Bolivar et al. 2001; Fahrni et al. 2003).

Members of this clade differ from other amoebae by possessing cytoplasmic MTOCs. The genus Acanthamoeba is among the most homogeneous and distinct genera of naked amoebae, and has been well studied molecularly (Stothard et al. 1998; Booton et al. 2004). Apart from acanthopodia and the presence of MTOCs in the cytoplasm, its distinctive features are the characteristic double-walled cysts with a stellate endocyst in most species. Balamuthia mandrillaris also shows cytoplasmic MTOCs, and the morphological differences between this species and Acanthamoebidae might be due to the specificity of its biology (Deol et al. 2000).