Brachysomophis longipinnis is an eel in the family Ophichthidae (worm/snake eels).[1] It was described by John E. McCosker and John Ernest Randall in 2001.[2] It is a marine, temperate water-dwelling eel which is known from a single specimen collected from Taiwan, in the northwestern Pacific Ocean.[1] [3] It is known to dwell at a depth of 50 metres, and is known to reach a total length of 42.1 centimetres.[1]
The species epithet "longipinnis" is derived from the Latin words "longus" and "pinnus", and means "long fin".[1] The IUCN redlist currently lists the species as Data Deficient, due to the extremely limited number of specimens recorded.[3]