1. Department of Geology and Geophysics, and Museum of Natural Science, Louisiana State University, Baton Rouge, LA, USA;
2. Paleobotany and Paleoecology, Cleveland Museum of Natural History, Cleveland, OH, USA;
3. Department of Geosciences, Princeton University, Princeton, NJ, USA;
4. Department of Geological Sciences, University of Missouri, Columbia, MI, USA;
5. Department of Paleobiology, Smithsonian Institution, National Museum of Natural History, Washington DC, USA