Complex sentence: Airbreathing catfishes are fishes comprising the family Clariidae of Order Siluriformes, part of the Actinopterygii (ray-finned fishes).
Split into simpler sentences: Airbreathing catfishes are fishes comprising the family Clariidae. Family Clariidae is part of Order Siluriformes, part of the Actinopterygii (ray-finned fishes).