Synaphobranchus dolichorhynchus is an eel in the family Synaphobranchidae (cutthroat eels).[1] It was described by Einar Hagbart Martin Lea in 1913, originally under the genus Leptocephalus.[2] It is a marine, subtropical eel which is known solely from larval specimens discovered in the northern Atlantic Ocean. It is known to dwell at a depth range of 100mto150mm (300feetto490feetm).[1]