Calamagrostis planifolia (Kunth) Trin. ex Steud., Nomencl. Bot. (ed. 2) 1: 251. 1840. Deyeuxia planifolia Kunth, Nov. Gen. Sp. (quarto ed.) 1: 145. 1815[1816]. Arundo planifolia (Kunth) Poir., Encycl. 4: 707. 1816.

Sylvester, Steven P., Soreng, Robert J., Bravo-Pedraza, William J., Cuta-Alarcon, Lia E., Giraldo-Canas, Diego, Aguilar-Cano, Jose & Peterson, Paul M., 2019, Paramo Calamagrostis s. l. (Poaceae): An updated list and key to the species known or likely to occur in paramos of NW South America and southern Central America including two new species, one new variety and five new records for Colombia, PhytoKeys 122, pp. 29-78 : 29

Calamagrostis planifolia (Kunth) Trin. ex Steud., Nomencl. Bot. (ed. 2) 1: 251. 1840. Deyeuxia planifolia Kunth, Nov. Gen. Sp. (quarto ed.) 1: 145. 1815[1816]. Arundo planifolia (Kunth) Poir., Encycl. 4: 707. 1816.

Type. PERU. In montanis Andinum Peruvianorum prope Guangamarca, 1250 hexap. [2286 m], 1833, Bonpland s.n. (holotype: P (P00729787 [image!]); isotype: BAA (BAA00001855 [image!]) fragm. ex P, P (P030106 [image!]) fragm., LE (LE-TRIN-1801.01!) fragm. ex Herb. Willd. 176).

= Deyeuxia pubescens Pilg., Bot. Jahrb. Syst. 25(5): 712. 1898, syn. nov. Calamagrostis pubescens (Pilg.) Pilg., Bot. Jahrb. Syst. 42: 60. 1908, syn. nov. Type: COLOMBIA. [Crescit in monte ignivomo Pasto] Volcán de Pasto, 3400 m alt., 9 Dec. 1869, Stübel 389b (lectotype, designated by Vega and Rúgolo de Agrasar (2013: 28): BAA (BAA00000811 [image!]) fragm. ex B; isolectotype: US (US00406355!) fragm. ex B).

= Calamagrostis pittieri Hack., Oesterr. Bot. Z. 52(3): 108. 1902, syn. nov. Type: COSTA RICA. Cerro de Buena Vista, pres du sommit, [prope cacumen, Valle du General], 3100 m alt., 19 Jan. 1891, Pittier s.n. Pl. Costaric. Exs. 3359 (holotype: W (W19160029198 [image!]); isotypes: B, BR (BR0000006865702 [image!]), BAA (BAA00000766 [image!]) fragm. ex B).

Comments.

Calamagrostis pittieri , recorded for Costa Rica, Colombia and Venezuela ( Morales Quirós 2003; Hokche et al. 2008; Giraldo-Cañas 2011, 2013; Giraldo-Cañas et al. 2016) is synonymised under Calamagrostis planifolia as no satisfactory characteristics were found to separate the two. Both have spikelets with florets bearing a pilose rachilla extension with hairs reaching from ¾ to passing the apex of the lemma, an awn inserted in the upper half of the lemma, 2 anthers that usually are short, ca. 1-1.4 mm long and leaf blades that are usually flat (sometimes drying convolute) with variable indumentum.

Calamagrostis pubescens was considered an endemic species to Colombia ( Giraldo- Cañas 2013) and only known from the type specimen that was collected in southern Colombia from hills surrounding Pasto of departamento Narino. The B holotype was destroyed during World War II, with fragments only remaining at BAA and US. The BAA fragment consists of spikelets whose size and characteristics match C. planifolia (Zulma Rúgolo de Agrasar, pers. comm.), and the description of vegetative characteristics in the protologue also matches C. planifolia and so we consider C. pubescens a synonym of C. planifolia . Nevertheless, further study is needed for the C. planifolia complex in Colombia and there are certain crucial characters, such as number of stamens that need to be verified in these taxa. The C. pubescens BAA fragment lacked anthers (Zulma Rúgolo de Agrasar, pers. comm.) and Pilger (1898: 712) did not describe them.