1. Department of Earth and Environmental Sciences, University of Michigan, University Avenue, Ann Arbor, MI 48109-1079, USA
2. Museum of Paleontology, University of Michigan, University Avenue, Ann Arbor, MI 48109-1079, USA
3. Universidade do Contestado, Centro Paleontológico da Universidade do Contestado, Mafra, SC 89300-000, Brazil