Southwest Pacific: endemic to New Zealand.
Occurs in rock pools and surge zones.
Adults restricted to tide pools.
May remain out of water under rocks or seaweed.
Feeds on mollusks and minute crustaceans, including barnacles.
This agile species eludes predators by alternately remaining motionless, then rapidly darting to a new location.
Feeding occurs even in the swash zone where the fish rapidly darts with the surge and clinging to the rock as the water recedes, often being left exposed on the damp open rock.
Breathes air when out of water.
Enneapterygius medium (Günther, 1861)
Helcogramma medium (Günther, 1861)
Tripterygium medium Günther, 1861