The shortdorsal cutthroat eel (Synaphobranchus brevidorsalis, also known commonly as the shortfin cut-throat eel) is an eel in the family Synaphobranchidae (cutthroat eels). It was described by Albert Günther in 1887. It is a marine, deep water-dwelling eel which is known from the Indo-Pacific and western central Atlantic Ocean, including Zanzibar, Maldives, Australia, Japan, Suriname, and the Gulf of Mexico. It dwells at a depth range of , most often between , and leads a benthic lifestyle, inhabiting the continental slope. Males can reach a maximum total length of .