Douglasdeweya: A new genus, with a new species and a new combination (Triticeae: Poaceae)

Abstract

The new genus Douglasdeweya C. Yen, J.L. Yang & B.R. Baum is based on results from cytogenetical and morphological findings — PPStSt genome — and is segregated from the genus Pseudoroegneria — StSt and StStStSt genome. Several characters, such as the erect spike with very finely spinulose pubescence along the two main angles of the rachis, and glumes and lemmas with a very strong midrib forming a keel-like structure distinguish Douglasdeweya from Pseudoroegneria, which has a rather lax spike, a rachis that is glabrous along the two main angles, and glumes and lemmas without a keel-like structure. The genus is named in memory of Dr. Douglas R. Dewey, an outstanding scientist who worked on the biosystematics of the perennial Triticeae. Two species are described, one of which is new, Douglasdeweya wangyii C. Yen, J.L. Yang & B. R. Baum and the other a new combination Douglasdeweya deweyi (K.B. Jensen, S.L. Hatch, & J.K. Wipff) C. Yen, J.L. Yang, & B.R. Baum. A key to the two species is provided, together with details on their taxonomy, nomenclature, distribution, and cytology.Key words: PPStSt genome, narrow endemic.