A Vertically Embedded Orthoconic Nautiloid From the Pennsylvanian of County Clare, Ireland – An Unusual Case of ‘Distraction Sinking’?

Abstract

A vertically embedded orthoconic nautiloid is recorded for the first time from the Clare Shale Formation (Carboniferous; Pennsylvanian) of County Clare, Ireland. The specimen is compared to the few recorded examples of vertically preserved orthocones in the rock record and previously proposed models of this unusual preservation are reviewed. A new model of self-propelled accidental emplacement during predator avoidance manoeuvres is proposed as one possible mode of emplacement.