Tannudiscus Pokrovskaya (1959) [1] is a genus of eodiscinid trilobites belonging to the family Weymouthiidae Kobayashi T. (1943),[2] Order Agnostida (Salter 1864).

[3] It lived during the late Lower Cambrian, with remains found in Canada (Newfoundland), China (Gansu), The United Kingdom (England), and the Russian Federation (Tuva, Gorno-Altayskaya).

It is therefore considered likely that the Agnostina descended directly from a species assignable to Tannudiscus.

The glabella almost touches the anterior border and consists of two inflated lobes, the frontal one slightly wider than the posterior lobe—a characteristic that is further developed in the Condylopygidae.

Pygidial axis is conical, with seven or eight rings, and may or may not reach posterior border furrow.