DERMOTRICHIUM
(plural dermotrichia))
the fin ray, of 4 types:- ceratotrich (in cartilaginous fishes), actinotrich (in cartilaginous and bony fishes), lepidotrichs (only in bony fishes) and camptotrichs (in Dipnoi and Crossopterygi). Spiny rays in Actinopterygii may be called acanthotrichs. Also called dermatotrich