Fig. 1From: Middle Triassic gastropods from the Besano Formation of Monte San Giorgio, SwitzerlandStratigraphic section of the Besano Formation at site Point 902/Mirigioli, with distribution and relative abundance of trace fossils, calcareous algae, cephalopods, bivalves and gastropods. Modified after Röhl et al. 2001 (Fig. 4), based on the internal inventory of the PIMUZ collection. The stratigraphic positions of four described specimens are indicatedBack to article page