Phase contrast and scanning electron microscopy of a soil amoeba, <i>Hartmannella glebae</i>

The genera Hartmannella and Acanthamoeba have been controversial. Some species of Acanthamoeba have been cited as species of Acanthamoeba, Mayorella, or Amoeba and a confusing lack of agreement persists in current literature. The genus Hartmannella was redefined by Page in 1967 to include those species which assumed a simple monopodial, limax-like form during locomotion and, where known, the cysts were smooth-walled and rounded with no opercula. The genus Acanthamoeba, on the other hand, possessed tapering, hyaline pseudopods (acanthopodia) and a cyst made up of an ectocyst and a polyhedral or stellate endocyst, with excystment by removal of opercula.</jats:p