Stipa exigua (Thurberg) Columbus & J.P. Smith
Stipa exigua (Thurberg) Columbus & J.P. Smith is a synonym sensu Romaschenko et al., 2011 of:
Piptatheropsis exigua (Thurberg) Romaschenko, P.M. Peterson & Soreng, an accepted species name sensu Romaschenko et al., 2011.