Reiswig and Mackie, 1983
Definition: Porifera with discrete cells. There is a skin-like pinacoderm consisting of discrete cells with few if any junctions between them (so called "gap-junctions"). pinacocytes may be perforated by pores in some members (then called "porocytes"). Larvae are either simple parenchymella larvae without special spicule types (although they have spicules) or hollow blastula-types.
Two classes: Class Demospongiae with siliceous spicules, either tetraxones or monaxones, with triangular or hexangular axial filament, and Class Calcarea with calcareous triactines/tetractines without axial filament.
Remarks: This subphylum is not well-established because the possession of discrete cells is probably a primitive character (all Metazoans have them). The name "Pinacophora" was recently introduced because the earlier name "Cellularia" was considered misleading for that reason. However, the name Pinacophora has the same problem: the pinacoderm of discrete cells is entirely homologous with the syncytial pinacoderm. Since the use of taxon names above the family level is unrestricted by rules of priority we are free to choose, and we prefer the Reiswig and Mackie name.