Foureyes Four-fin blenny Fourfinger threadfin Four-fingered lipsucker Fourhorn poacher Fourhorn sculpin Fourline blenny Fourline hogfish Fourline snakeblenny Fourline tonguesole Fourline wrasse Fourlined terapon Fourlined tonguesole Four-lined wrasse Fourpored blenny Foursaddle grouper Fourspine cichlid Fourspine leaffish Fourspine scorpionfish Fourspine sculpin Fourspine stickleback Four-spined glass perchlet Four-spined leatherjacket Fourspot butterflyfish Fourspot flounder Four-spot megrim Fourspot triplefin Fourspotted barb Four-spotted goby Four-stripe goatfish Fourteen-gill hagfish Fourwing flyingfish Fowler's pearlfish Fowler's rockskipper Fowler's snake eel Fowler's surgeonfish Foxface Foxfish Fragile cardinalfish Fragile grenadier Fragile lantern fish Frail cardinalfish Frail gourami Frailscale goby Francis' goatfish Frans' cardinalfish Fransmadam Franz's cusk Fraser’s lanternfish Fraser's goatfish