Bony support of the fins in (bony) fishes. Each element actually is a bilateral pair of bones, which may be fused and rigid as in the hard ray or spines, or only partially fused as in the unbranched soft rays or not fused as in (branched) soft rays. In systematics fin-rays are an often used character to identify genera, species, subspecies and/or populations of bony fishes (see fin-ray formula).