A key to the North American genera of Stipeae (Poaceae, Pooideae) with descriptions and taxonomic names for species of Eriocoma, Neotrinia, Oloptum, and five new genera: Barkworthia, x Eriosella, Pseudoeriocoma, Ptilagrostiella, and Thorneochloa Author Peterson, Paul M. Department of Botany MRC- 166, National Museum of Natural History, Smithsonian Institution, Washington, DC 20013 - 7012, USA peterson@si.edu Author Romaschenko, Konstantin Department of Botany MRC- 166, National Museum of Natural History, Smithsonian Institution, Washington, DC 20013 - 7012, USA Author Soreng, Robert J. https://orcid.org/0000-0002-8358-4915 Department of Botany MRC- 166, National Museum of Natural History, Smithsonian Institution, Washington, DC 20013 - 7012, USA Author Reyna, Jesus Valdes Departamento de Botanica, Universidad Autonoma Agraria Antonio Narro, Saltillo, C. P. 25315, Mexico text PhytoKeys 2019 2019-07-16 126 89 125 http://dx.doi.org/10.3897/phytokeys.126.34096 journal article http://dx.doi.org/10.3897/phytokeys.126.34096 1314-2003-126-89 FFC2D06D486FF317CE32972BDE2BFF93 3348547 Eriocoma lettermanii (Vasey) Romasch., comb. nov. Stipa lettermanii Vasey, Bull. Torrey Bot. Club 13: 53. 1886 [Basionym] ≡ Stipa viridula var. lettermanii (Vasey) Vasey, Contr. U.S. Natl. Herb. 3(1): 50. 1892 ≡ Achnatherum lettermanii (Vasey) Barkworth, Phytologia 74(1): 9. 1993. Type: USA, Idaho, Snake River, Aug 1885, G.W. Letterman 102 (lectotype: US-556904! designated by Hitchcock, Manual. Grass. US ed. 1, 964. 1935 as to the collection no. 102 , Barkworth & Maze identifed the US specimen number, Taxon 31(2): 294 f. 6. 1982). Eriocoma lettermanii = Stipa viridula var. minor Vasey, Contr. U.S. Natl. Herb. 3(1): 50. 1892 ≡ Stipa occidentalis var. minor (Vasey) C.L. Hitchc., Vasc. Pl. Pacific NW 1: 714. 1969 ≡ Stipa minor (Vasey) Scribn., Bull. Div. Agrostol., U.S.D.A. 11: 46-47. 1898. Type: USA , Colorado, Kelso Mountain near Torrey's Peak, 13000 ft, 13 Aug 1885, G.W. Letterman 95 (lectotype: US-556903! designated by Hitchcock, Contr. U.S. Natl. Herb. 24(7): 253. 1925).