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).