Nemertodermatida is a class of Acoelomorpha, comprising 18 species of millimetre-sized turbellariform, mostly interstitial worms.

[1] The order Nemertodermatida contains two families with 6 genera.

[2] The high level of cryptic diversity in this meiofauna group however implies that the number of nemertodermatid taxa may be underestimated.

[3] The family Ascopariidae Sterrer, 1998[4][5] contains two genera.

[2] The family Nemertodermatidae Steinböck, 1930 contains four genera.