Noturus insignis (margined madtom) is a small species of North American catfish belonging to the family Ictaluridae.

The margined madtom is yellow to dark gray on the upper side of the body, and a pale shade on the underside.

The species ranges from Lake Ontario drainages southward to Georgia.

Margined madtoms inhabit clear-water streams, taking shelter among rocks, gravel, and boulders.

Its eggs are laid in large quantities, and are guarded by the male parent.