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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.

Key to the genera
1
Cell spiny in appearance
2
Usually with slender pseudopodia at anterior edge only
3
2
Cytoplasm colorless
Cytoplasm green, yellow or brown
3
Anterior pseudopodia usually less than half cell length
4
Anterior pseudopodia usually more than half cell length
5
4
With intracellular parasomes
Without parasomes
5
Amoebae with locomotive and floating forms
6
Amoebae apparently only with a floating stage
6
Several pseudopodia projecting from anterior edge
7
Only one or two leading pseudopodia from anterior edge
8
7
Active locomotive form, usually club-shaped
Striolatus
Active locomotive form, usually trapezoidal with pseudopodia from a mound-like base
Triaenamoeba
8
Leading pseudopodium broadly tapering
9
Leading pseudopodium flagellum-like
Podostoma
9
Leading pseudopodium with very fine tip
Subulamoeba
Leading pseudopodium with blunt tip
Oscillosignum

 

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