[Radiolaria Polycystina] In Nassellaria: helmet shaped portion of the shell of the Nassellaria associated with the apical horn; its base is formed by the top of the cephalis. Also called apical cupola.

[Radiolaria Phaeodaria] Dome-shaped to irregular sack-like extension of valve of inner shell, usually with triangular base (Phaeodarian cell features 8, inner shell) (Coelodendridae).

Alternative form for Galea : apical cupola.