Gunnels are brightly coloured with small, elongate bodies covered in tiny scales.They have a long dorsal fin which is entirely covered in spines and if they have pelvic fins, they are tiny. Gunnels are commonly found in tidepools and shore waters in the cold parts of the Northern hemishere.Banded gunnel (Pholis fasciata): The banded gunnel has a blackish bar from the top of its head to the corner of its mouth with a creamy band right behind it. It has scarlet sides and dark bands on its dorsal fin. The banded gunnel has 10 to 11 yellowish gray saddles on its back and is found in the Arctic Ocean, to Southern Labrador and Western Greenland as well as in the North Pacific.It can reach 30 cm.
Rock Gunnel(Pholis gunnellus): The rock gunnel has a dark bar from its eye to its dorsal fin which curves underneath the eye to a point behind the mouth and it has no pale band. It has 10 to 14 black spots along its dorsal fin and its body colour changes with the background depending on where the gunnel is living. Generally, the rock gunnel is a yellowish to olive to reddish colour but is usually uniform. It is found from Labrador to Delaware Bay and the eastern North Atlantic. The rock gunnel can reach between 25 and 30 cm. Their diet includes small invertebrates and fish.