Hoplunnis sicarius is an eel in the family Nettastomatidae (duckbill/witch eels). It was described by Samuel Garman in 1899, originally under the genus Atopichthys. It is a marine, tropical eel which is known from the eastern central Pacific Ocean, including Mazatlan, Mexico, and Panama. It is known to dwell at a depth of 1,431 metres (4,695 ft), and inhabits substrates. Unlike many eel species, it does not form burrows.