Nikisha Patel1, Chun-Xiang Li2, Li-Bing Zhang3, David S Barrington4. 1. Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, TN 37919, USA. Electronic address: npatel70@utk.edu. 2. State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China. 3. Missouri Botanical Garden, P.O. Box 299, St. Louis, MO 63166-0299, USA; Chengdu Institute of Biology, Chinese Academy of Sciences, P.O. Box 416, Chengdu, Sichuan 610041, China. 4. Pringle Herbarium, Department of Plant Biology, University of Vermont, Burlington, VT 05405, USA.