Melanochlamys cylindrica is a species of bubble snail in the family Aglajidae.

[2] M. cylindrica is found on the coast of New Zealand's North and South Islands.

[3] Body is long and cylindrical in shape with a uniformly black colour that may feature an iridescent blue sheen.

[3] A large muscular mouth part (known as the buccal bulb) is contained in the anterior half of the body cavity.

[5][6] M. cylindrica is most commonly found in the mid-intertidal zone in algal turf and on rock platforms.