Order Gracilipodida Lahr and Katz, 2011
Diagnosis: Amoeboid organisms without cilium or centrosomes; flattened, fan-shaped or irregularly branched, with short conical subpseudopodia or fine hyaline hair-like subpseudopodia or pseudopods coming out from the cell body; Pseudopods are thin, filiform. Single or multinucleated. Cysts with smooth single-layered wall. Other morphological features outlined in Kudryavtsev 2009: flattened locomotive form either with expanded fan-shaped hyaloplasm regions producing thin sub-pseudopodia.
Type species: Flamella magnifica Schaeffer 1926
Etymology: from the Latin gracilis (slender) and pedes (feet), in reference to the ability shared by these organisms to produce thin pseudopodia.
Putative Synapomorphy: filiform pseudopodia.