[3] It is a marine, deep water-dwelling eel which is known from the western Indian Ocean, including the Gulf of Aqaba and possibly the Gulf of Suez.

A single specimen was recorded in the Mediterranean Sea from Israel in 1993.

[4] It dwells at a depth range of 300 to 500 metres (980 to 1,640 ft), and swims in a zigzag motion near the bottom.

[2] The species epithet "trewavasae" was given in honour of British ichthyologist Ethelwynn Trewavas.

R. trewavasae is sometimes caught in traps and trammel nets.