Fig. 2

Holdfast of Finitiporus boardmani from a hardground capping the lower carbonate of the Massie Formation, Napoleon quarry, Indiana, USA. The proximal end of the holdfast, where detachment from the theca occurred, is labeled ‘p’; the distal end of the holdfast, where attachment to the substrate occurred via an expanded cemented disc, is labeled ‘d’. Three elongate plates of the stem-like holdfast (labeled ‘1’, ‘2’, and ‘3’) are visible; note that only the plate labeled ‘1’ is exposed completely. Scale bar  10 mm