Stigmadiscus Rasetti, 1966,[2] is a genus of Lower Cambrian Eodiscinid trilobite belonging to the family Weymouthiidae Kobayashi (1943) [3] Order Agnostida (Salter 1864) [4] It lived during the Botomian stage,[1] = late Lower Cambrian Stage 4 (upper of two stages subdividing the un-named Series 2); the upper Botomian Stage boundary corresponds to base of both the Middle Cambrian Wuliuan stage and Miaolingian Series.

Stigmadiscus resembles Acidiscus in having a relatively short glabella, distinct S1 and S2 lateral furrows, and a slender occipital spine.

In fact, according to Cotton & Fortey (2005, fig.

3) [5] consensus is that Stigmadiscus and Bolboparia Rasetti, 1966, are sister taxa of Acidiscus.

This Agnostida-related article is a stub.