Cortaderia planifolia Swallen, Contr. U.S. Natl. Herb. 29: 253. 1948.

Testoni, Daniel & Linder, H. Peter, 2017, Synoptic taxonomy of Cortaderia Stapf (Danthonioideae, Poaceae), PhytoKeys 76, pp. 39-69 : 61

14. Cortaderia planifolia Swallen, Contr. U.S. Natl. Herb. 29: 253. 1948.

Type.

Colombia, Dept. Valle del Cauca, Cordillera Occidental, extremo N, vertiente NW, entre Alto del Buey y Quebrada de los Ramos , 12 Oct. 1944, J. Cuatrecasas 18059 (lectotype, designated as holotype by Connor & Edgar, Taxon 23: 601 (1974): US 00133442!).

Etymology.

planus (Latin) = flat + folium (Latin) = leaf. Leaf-blades flat.

Taxonomy.

Cortaderia planifolia has many similarities to Cortaderia pungens , but is separated by the flat or folded, but not rolled, leaves; somewhat taller tussocks (05-1 m, compared to 0.2-0.5m); adaxial leaf surface above the ligule glabrous; glumes 8-15 mm long, compared to 12-16 mm; lemmas 4-8 mm, compared to 3-4 mm long; lemma awn less than 8 mm long, compared to more than 9 mm in Cortaderia pungens . These numerous small differences suggest that these are two species.

It has also been grouped with Cortaderia hapalotricha , from which it differs by the smaller size, the flat leaves glabrous above the ligule, the shorter lemma awn and setae.

Leaf anatomy not investigated.