O. scutellus is named after the Latin scutella for “saucer”, due to its flattened disc-like head.

Ophryotrocha scutellus has a dorsoventrally rounded and flattened prostomium, similar to O. platykephale, from which this species differs in jaw morphology, the form of its parapodia and the absence of branchiae.

It lacks eyes; it possesses long, cirriform paired antennae, with palps being inserted lateroventrally on the prostomium.

Its pygidium has a terminal anus, with two pygidial cirri that measure as long as its antennae and shows a short appendage ventrally.

[1] It was first found in a minke whale carcass at a depth of 125 metres (410 ft) in the Koster area in Sweden, and from sediment at 104 metres (341 ft) beneath a fish farm in Hardangerfjord in Norway.