The Flabellinea are a phylum of Amoebozoa

Amoebozoa

The Amoebozoa are a major group of amoeboid protozoa, including the majority that move by means ofinternal cytoplasmic flow. Their pseudopodia are characteristically blunt and finger-like,...

. During locomotion the cells are flattened and have a clear layer called hyaloplasm along the front margin. Some form slender subpseudopodia projecting outward from the hyaloplasm, but the cell mass does not flow into these as in true pseudopodia, and advances without a definite central axis as in the Tubulinea

Tubulinea

The Tubulinea are a major grouping of Amoebozoa, including most of the larger and more familiar amoebae likeAmoeba, Arcella, and Difflugia.-Characteristics:During locomotion most Tubulinea have a roughly cylindrical...

. They also lack distinctive features like shells and flagella

Flagellum

A flagellum is a tail-like projection that protrudes from the cell body of certain prokaryotic and eukaryotic cells, and plays the dual role of locomotion and sense organ, being sensitive to chemicals and temperatures outside the cell. There are some notable differences between prokaryotic and...

, and are united mainly by evidence from molecular trees.

The name Discosea, introduced by Cavalier-Smith et al. (2004), refers a similar but slightly larger group.

Discosea has been described as containing Glycostylida, Himatismenida

Himatismenida

Himatismenida is a Amoebozoa order.It includes the species Cochliopodium gallicum.It has been described as a member of Discosea, along with Glycostylida and Dermamoebida....

, and Dermamoebida.