Festucalex prolixus is a species of marine fish of the family Syngnathidae. It is found in the Western Central Pacific, from the Sulu-Celebes Sea and around west Papua New Guinea, Indonesia, including Cenderawasih Bay.[1] Known specimens come from trawls of NaNm (-2,147,483,648feet), so it is thought to inhabit waters deeper than 40m (130feet).[2] Very little is known about this species, but it is expected to be ovoviviparous and to feed on small crustaceans.[1]