[Foraminifera] Any protruding outgrowths of the skeletal meshwork. Apophyses on spicules may branch repeatedly and remain separated from those of neighboring spicules (Pristacantha octodon 2 , Pristacantha octodon 3), or the branches may coalesce forming elaborate latticed shells (Dictyacantha tetragonopa, Dictyacantha tetragonopa 2 ). Primary apophyses are those inserted directly into the spicule; secondary ones rise from the primary, and so on.

[Radiolaria Polycystina] In Nassellaria and Spumellaria: any external or internal protruding outgrowth of the skeletal meshwork.