The Global Stratotype Section and Point (GSSP) for the base of Toarcian Stage is proposed at the base of limestone Bed 15e at Ponta do Trovão, in the Peniche section (39º22’15’’ N, 9º23’07’’ W) (Lusitanian Basin, Portugal) located 80 km north of Lisbon.

The base of the Toarcian Stage is marked by the FO of the ammonite Dactylioceras (Eodactylites) simplex. Co-occurring species, which help to define the lower part of the Polymorphum Zone in the absence of D. (E.) simplex, include D. (E.) pseudocommune and D. (E.) polymorphum. The ammonite association of D. (Eodactylites) ssp. and other species e.g. Protogrammoceras (Paltarpites) cf. paltum, Lioceratoides aff. balinense and Tiltoniceras aff. capillatum is particularly significant for the boundary definition.

The section at Almonacid de la Cuba (Iberian Range, Spain) provides complementary data of the ammonite succession in the Northwest European Hawskerense and Paltum Subzones and magnetostratigraphical data.

A full description is currently in preparation.