Toucasia bafflestone, which is dominated by complete valves of requieniid rudists (Toucasia sp.). The inner aragonitic layer of the rudist
shell is replaced by blocky calcite, and the outer foliated layer is calcite. The matrix is mainly lime mudstone with abundant benthic foraminifers, rudist fragments and rare dasyclad algae (Fig. 9c). This facies is dominated by low energy micrite and benthic foraminifers. We interpret it as an isolated biostrome developed in the back-reef environment.