Centro de Ciências Biológicas e da Natureza, Universidade Federal do Acre

Professor, Department of Botany & Rocky Mountain Herbarium, University of Wyoming

Full Professor in Systematic Botany, PLANTSEED Lab, University of Pisa

Professor of Genomics, Evolution and Bioinformatics, Arizona State University

IICAR-CONICET - Cátedra de Botánica, Facultad de Ciencias Agrarias, UNR

Curator, New York Botanical Garden

Real Jardín Botánico CSIC

Associate Professor of Botany, IB (PG) College, Panipat

UC Foundation Professor, University of Tennessee at Chattanooga

Associate Scientist, Florida Museum of Natural History, University of Florida