[clarification needed] Individuals are unicellular and spherical, usually around 30–80 μm in diameter, and covered with long radial axopods, narrow cellular projections that capture food and allow mobile forms to move about.

A few genera have no cell covering, but most have a gelatinous coat holding scales and spines, produced in special deposition vesicles.

The axopods of centrohelids are supported by microtubules in a triangular-hexagonal array, which arise from a tripartite granule called the centroplast at the center of the cell.

Structural comparisons with other groups are difficult, in part because no flagella occur among centrohelids, and genetic studies have been more or less inconclusive.

[9] Posterior molecular studies of 2018 have rearranged the classification of centrohelids into two taxa: Pterocystida and Panacanthocystida, which includes both Acanthocystida and the genus Yogsothoth.