Poa ana-molinae Soreng & L. J. Gillespie, 2025

Soreng, Robert J. & Gillespie, Lynn J., 2025, New species and infrageneric names in Poa L. (Poaceae): transferring species of Agrostopoa Davidse, Soreng & P. M. Peterson and Raimundochloa A. M. Molina and some notes on misidentifications, PhytoKeys 266, pp. 129-138 : 129-138

Poa ana-molinae Soreng & L. J. Gillespie nom. nov.

Koeleria trachyantha Phil. , Fl. Atacam. 55 (N o. 404). 1860: Basionym. Type: [ lectotype (here designated by V. Finot, G. Rojas & Soreng): SGO-O 63517 ; isolectotype: BAA (fragm. ex SGO-63517 ), US- ( SGO-PHIL-230 photo “ Trisetum brachyantherum Phil. ”), W-01160039938 (ex herb. Hackel, ex SGO-PHIL-230 , “ Trisetum brachyantherum Ph. ”), W 0028853 (ex SGO-230 or 63517?)]. Type Protologue: Chile, Prov. de Antofagasta, Paposo , Nov 1853, Philippi s. n.

≡ Parodiochloa trachyantha (Phil.) A. M. Molina , Parodiana 4 (1): 112–120, f. 1–2. 1986. ≡ Raimundochloa trachyantha (Phil.) A. M. Molina , Parodiana 4 (2): 402. 1986. ≡ Rostraria trachyantha (Phil.) Tzvelev ex Soreng , Contr. U. S. Natl. Herb. 48: 604, 4. 2003. (non- Poa trachyantha Hack., 1912 .).

Note.

The species is here renamed in honour of Dra. Ana María Molina, Argentine Botanist, Agrostologist.

According to Finot ( Finot 2022, p. 966), this unusual annual species occurs in the coastal Loma vegetation of the Atacama Desert in northern Chile and southern Peru (24 ° 50 ' – 33 ° 39 ' S), has peculiar rough upper glume and lemma surface texture “ escabroso-hirsutas, coriaceous ” and tightly contracted panicles similar to Rostraria cristata (L.) Trin. and lemmas with short apical awns ( 1–2 mm), the lemma apex sometimes apically short lobed (see Illustration, in Finot 2022, p. 965, Lámina 357). These characteristics are reminiscent of the densely scabrous and coriaceous lemmas with stiff apical awns in Poa flabellata (Lam.) Raspail (the type species of Parodiochloa C. E. Hubb. , also a synonym of Poa ). Curiously both of these species have short, stiff apical awns on the lemmas (rare in Poa ) and narrow, congested panicles (extreme in P. ana-molinae for Poa ).

Plastid and nrDNA data place Poa ana-molinae in well supported and consistent clades named “ Parodiochloa ” ( R plastid and r nrDNA clades; see Soreng et al. (2020) for clade coding), with formally named sections Poa sect. Parodiochloa (C. E. Hubb.) Soreng and P. sect. Tzvelevia (E. B. Alexeev) Soreng & L. J. Gillespie. The Rr - clade hitherto was demonstrated to contain a series of perennial species with narrow, compact, contracted panicles, from widely distributed sub-Antarctic oceanic islands and Tierra del Fuego [ P. cookii (Hook. f) Hook. f, P. flabellata , P. kerguelensis (Hook. f.) Steud. (type of Tzvelevia ≡ Poa sect. Tzvelevia ), P. ramosissima Hook. f. ] and one annual species with open panicles from south-eastern United States, P. chapmaniana Scribn. ( Gillespie et al. 2007; Refulio-Rodríguez et al. 2012; Persson and Rydin 2016; Soreng et al. 2022 b). Both of the annuals, P. ana-molinae and P. chapmaniana (type of P. sect. Diversipoa Chrtek & V. Jirásek) have one stamen per flower, but later has a web on the callus and lemmas with well-developed soft pubescence on the keel and marginal nerves and shorter hairs on the surface and open, pyramidal, thin-branched panicles, while the other taxa in the Parodiochloa clade (including P. ana-molinae ) lack callus hairs and lack much (at most, coarse and short) pubescence on their lemmas and have contracted panicles. The three sections are united here in a subgenus Parodiochloa . The two sections mentioned above were formerly placed in P. subg. Ochlopoa (Asch. & Graben) Hyl. However , the monophylly of the Ochlopoa clade as originally resolved and constituted ( Soreng and Gillespie 2007; Gillespie et al. 2008) no longer has support ( Soreng et al. 2020) in nrDNA trees and we here restrict subg. Ochlopoa to encompass species included in P. sect. Micrantherae Stapf. (type P. annua L.), including P. cyrenaica A. Durand & Barratte (formerly the sole species in the genus Libyella Pamp. ).