Muraenichthys gymnopterus is an eel in the family Ophichthidae (worm/snake eels). It was described by Pieter Bleeker in 1853, originally under the genus Muraena. It is a marine, tropical eel which is known from the western Pacific Ocean, including China, Indonesia, and India. It inhabits rocky reefs in shallow, warm seas. Males can reach a maximum total length of 30 centimetres (12 in). The diet of M. gymnopterus consists of finfish and phytoplankton.