Istiblennius lineatus, the lined rockskipper, is a species of combtooth blenny found in coral reefs in the Pacific and Indian oceans.

It is also commonly known as the lined blenny, black-lined blenny, or thin-lined rockskipper.

It can reach a maximum of 15 cm (5.9 in) TL.

This species can be found in the aquarium trade.

This Blenniidae article is a stub.