Penard Labs

The Fascinating World of Amoebae

2.0. Centramoebida Rogerson and Patterson 2002, emend. Cavalier-Smith 2004
Flattened with prominent subpseudopodia, flexible and tapering to a fine tip and sometimes furcated near their base (acanthopodia); without adhesive uroid; one species in culture appears as a branched, flattened sheet without subpseudopodia; some species sporocarpic and protosteloid.

2.1. Acanthamoebidae Sawyer and Griffin 1975, emend. Tice et al. 2016
Flattened to dome shaped amoebae with flabellate-type pseudopodia some with furcate subpseudopodia.

2.1.1. Acanthamoeba Volkonsky 1931
Locomotive form usually between 12 and 40 µm in length. Pseudopodia clear, slowly eruptive, and occasionally branching at base. With numerous, slender, and tapering subpseudopodia (acanthopodia) giving the cell a spiny appearance. Cytoplasm without crystals but frequently with small lipid globules and an obvious contractile vacuole. Nucleus spherical with a central nucleolus. Posterior uroid temporary. Cysts common, often with 2 layers, a thick, wrinkled outer ectocyst and an inner polygonal endocyst and a wall pore with operculum. Some species sporocarpic and protosteloid.
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Acanthamoeba sp.

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Acanthamoeba pyriformis (Olive & Stoianovitch 1969) Spiegel & Shadwick 2016

2.1.2. Luapeleamoeba Shadwick & Spiegel 2016
Flabellate, uninucleate amoebae with a single broad, hyaline lamellipodium with blunted triangular subpseudopodia at the leading edge. Following the lamellipodium is a thick granuloplasmic region containing a single nucleus and a conspicuous contractile vacuole that is usually posterior to the nucleus.The floating form is round but not smooth. Cysts rare and thin-walled in the type species. Subaerial fruiting bodies have been observed in the type species.
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Luapeleamoeba arachisporum (Olive & Stoianovitch 1969) Tice & Brown 2016

2.1.3. Vacuolamoeba Tice, Geisen, & Brown 2016
Irregular shaped amoebae, pseudopods variable with anterior hyaloplasmic lamellopodial extensions free of inclusions. Acanthopodial extensions can form from all areas of the cell body. Occasionally cells produce uroid with lamellopodial form that includes filose uroidal extensions. Cells most often with 1 vesicular nucleus with a central nucleolus. Cells have 2 nuclei have been observed. Cell body often has many ca. 4-5 vacuoles, sometimes with one or more contractile vacuoles. Cysts round to irregularly shaped with a single wall. Cysts usually form individually rather than in clusters.
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Vacuolamoeba acanthoformis Tice, Geisen, & Brown 2016

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Vacuolamoeba sp.

2.1.4. Dracoamoeba Tice & Brown 2016
Amoebae having ramose pseudopodia with the ability to form lamellapodium with acanthapodial subpseudopodia. Pseudopods of all forms made up of hyaloplasm and used for locomotion and feeding. Cell body made of granuloplasm.
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Dracoamoeba jomungandri Tice & Brown 2016