The Gulper Catfish Asterophysus batrachus is a rather small predatory fish (max 25cm), but it has a ferocious appetite! It originates from the Orinoco and Rio Negro river basins of Venezuela and Brazil and can be found occasionally in the aquarium trade. They can live to over 15 years if kept in good conditions. Its stomach is extremely flexible which allows it to swallow prey of similar size. It usually swallows prey head-first. Rough teeth allow it to hold on to the sides of the prey while it slowly gets devoured. Other similar sized fish are stunned when a gulper suddenly decides to swallow it whole! Check out this amazing video of a gulper swallowing its prey. Within a few days the fish will be completely digested.
I thank bomber banks ENT for publishing this video.