[1] is a genus of eodiscinid trilobite 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 & Nova Scotia), China (Gansu), The United Kingdom (England), Germany (Silesia), Poland (Holy Cross Mountains), the Russian Federation (Tuva, Gorno-Altayskaya, Kuznetsk Alatau), and the United States (Massachusetts, New York State).

Weymouthia and Runcinodiscus had previously been viewed as closely allied with Serrodiscus (e.g. Rushton op.

Front of glabella does not extend to the anterior furrow; preglabellar field short (sag.)

[4] Serrodiscus could protect its soft underside by enrollment and it has been demonstrated that the ventral spines on the pygidial doublure interlock the nodes on the cephalic border, probably improving defense.