Filozoa

The Filozoa are a monophyletic grouping within the Opisthokonta. They include animals and their nearest unicellular relatives.
Three groups are currently included within the clade Filozoa:

Group Filasterea - recently described to include the genera Ministeria and Capsaspora
Group Choanoflagellatea - collared flagellates
Kingdom Animalia - the group of which all extant animals belong to
Etymology

The name Filozoa originates from the Latin word filum meaning "thread" and the Greek word zōion meaning "animal".

Phylogeny

Below is a phylogenetic tree of Filozoa and the groups most closely related to the Filozoa :

Characteristics

The ancestral opisthokont cell is assumed to have possessed slender filose projections or 'tentacles'. In some opisthokonts these were lost. They are retained in Filozoa, where they are simple and non-tapering, with a rigid core of actin bundles. In choanoflagellates and in the most primitive animals, namely sponges, they aggregate into a filter-feeding collar around the cilium or flagellum; this is thought to be an inheritance from their most recent common filozoan ancestor.