Family PLAKINIDAE Schulze, 1880

Definition. Homosclerophorida with siliceous spicules, when present, represented by diods, triods and/or calthrops; spicules are lacking in two species. Aquiferous system sylleibid-like or leuconoid, made up by eurypylous or aphodal choanocyte chambers (Lage et al. 2018).