Family Vexilliferidae Page, 1987
Diagnosis: Amoebae with long, slender subpseudopodia (usually more than one) frequently giving a spiny appearance to the cell. Subpseudopodia from hyaline region never branched. Locomotive form usually longer than broad. Floating form frequently with slender, radiating pseudopodia.
By electron microscopy, the cell surface of those examined is seen as an amorphous glycocalyx, or more commonly, is differentiated into discrete hexagonal glycostyles. Pseudopodia of those species examined have a filamentous core. Included in this family are several genera for which no ultrastructural information is available.
As new information is obtained, some genera may have to be relocated to other familial positions; for now all amoebae in this family share the feature of having one or more markedly slender subpseudopodia.