A. exigua may refer to:
Acaena exigua, a rose endemic to Hawaii Acrolophus exigua, a South American moth Acrotona exigua, a rove beetle Aglaia exigua, a New Guinean mahogany Agrostis exigua, a North American bunchgrass Agyneta exigua, an African spider Alcadia exigua, a land snail Alcyna exigua, a sea snail Aleuria exigua, a cup fungus Anaxipha exigua, a sword-tail cricket Ancilla exigua, a sea snail Andrena exigua, a nonparasitic bee Antoniettella exigua, a colonial invertebrate Anxietas exigua, a sea snail Asterias exigua, a starfish native to the northeastern Atlantic Ocean and the Mediterranean Sea Attalea exigua, a New World palm