They grow to a length of about two inches and feed on the leaves of the Northern catalpa and, more commonly, the Southern catalpa. The fully developed caterpillar has a conspicuous black spine or horn on the back at the insect's rear. Catalpa sphinx moth caterpillar is usually plump with forage and are beautiful when mostly yellow with black lines and spots in the last color phase. They are highly desired by fisherman as bait.


