What is "spinyfin"

Spinyfins are a family, Diretmidae, of beryciform fishes. The name is from Greek, di meaning "two" and eretmos meaning "oar". They are found worldwide in deep waters, as deep as .

As the common name implies, spinyfins have heavy spines along their fins. They have deep, compressed bodies, and almost vertically aligned mouths. They are dark silver in colour, and reach up to in length.