The turtle-jawed moa-nalo (Chelychelynechen quassus), also formerly referred to as the large Kauai goose, is a species of moa-nalo, one of a group of extinct, flightless, large goose-like ducks, which evolved in the Hawaiian Islands of the North Pacific Ocean. It was described in 1991 from subfossil material collected in 1976 by Storrs Olson from the calcareous Makawehi dunes on the south-eastern coast of the island of Kauai. Its remains have also been found at the nearby Makauwahi Cave site.