Cyema is a monospecific genus of marine ray-finned fish belonging to the monotypic family Cyematidae.

[2] The type locality of C. atrum was given as the South Pacific from Challenger station 295 from a depths of 1,500 fathoms (9,000 ft; 2,700 m) and the Antarctic Ocean from Challenger station 158 from a depth of 1,800 fathoms (10,800 ft; 3,300 m).

[7] Cyema has acompressed body with its anus in the middle, the trunk and the tail are of equal length.

It has tiny, closeley set teeth with recurved points on the jaws and on the vomer.

In the Atlantic Ocean, it as far north as the waters off southwestern Greenland and at the southern boundary of the Irminger Sea.

The snipe eel has been recorded off southern Japan and in the Eastern Pacific, from British Columbia and Oregon south to Panama and Chile.