Gillaroo (Salmo stomachicus; historically included in Salmo trutta) is a variety of trout which eats primarily snails and is only proven to inhabit Lough Melvin in Ireland. The name gillaroo is derived from the Irish for "red fellow" (giolla rua); this is due to the fish's distinctive colouring. It has a bright, buttery golden colour in its flanks with bright crimson and vermilion spots. The gillaroo is characterised by these deep red spots and a "gizzard", which is used to aid the digestion of hard food items such as water snails.