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Actinopterygian node G (characteristic of a possible clade uniting the amphycentridae with the redfieldiidae and dorypteridae): Branchiostegal rays are reduced in numbers.
Actinopterygian node H: Blunt and rounded snout, reduced preopercular, absence of suborbitals, reduction or absence of marginal teeth, presence of crushing tooth plates, deep and laterally compressed body.
The redfieldiid, amphicentrid and dorypterid families appear to have formed a clade through the Carboniferous, Permian and Triassic, characterised by the reduction of branchiostegal rays, in the gill region, from the primitive actinopterygian series composed of 12-13 elements to a single one in certain forms.
The amphicentrids - such as Amphicecntrum, the Carboniferous form above - were typically deep bodied and laterally compressed, with very long anal and dorsal fins, while the paired fins were characteristically small. The Amphicentrum also possessed an array of flattened teeth and bony tooth plates, presumably used for crushing tough food items, such as hard-shelled prey.