Rostrum size of Paddlefish (Polyodon spathula) (Acipenseriformes : Polyodontidae) front the Mississippi delta

Paddlefish rostra vary in size and shape suggesting existence of multiple m orphotypes. Measurements for 118 adult paddlefish from a Mississippi delta river indicate that the rostrum becomes shorter, narrower, and straighter a s a fish grows. Negative allometric growth of rostra, and high variation wi thin size classes, may obscure existence of distinctive rostral morphotypes .