Nettastoma syntresis is an eel in the family Nettastomatidae (duckbill/witch eels). It was described by David G. Smith and James Erwin Böhlke in 1981. It is a marine, deep water-dwelling eel which is known from the western central Atlantic Ocean, including the Bahamas, Cuba, and the northeastern Gulf of Mexico. It dwells at a depth range of 0 to 641 metres (0 to 2,103 ft). Males can reach a maximum standard length of 55 centimetres (22 in).