Poa infirma Kunth in Humb., Bonpl. & Kuntz, Nov. Gen. Sp. 1: 158. 1816.

Ortega-Olivencia, Ana & Devesa, Juan A., 2018, Updated checklist of Poa in the Iberian Peninsula and Balearic Islands, PhytoKeys 103, pp. 27-60: 27

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Poa infirma Kunth in Humb., Bonpl. & Kuntz, Nov. Gen. Sp. 1: 158. 1816.


13. Poa infirma Kunth in Humb., Bonpl. & Kuntz, Nov. Gen. Sp. 1: 158. 1816. 

Megastachya infirma  (Kunth) Roem. & Schult., Syst. Veg. 2: 585. 1817.

Eragrostis infirma  (Kunth) Steud., Nomencl. Bot. ed. 2, 1: 563. 1840.

Poa annua var. exilis  Tomm. ex Freyn, Verh. K. K. Zool.-Bot. Ges. Wien 27: 469. 1878. [Type: "So auf sonnigen, trockenen Grasplätzen der Macchien, meist in Gesellschaft von Asterolinon, Euphorbia peploides, E. xigua und anderen Zwergpflanzen stellenweise häufig, bisher aber nur läng der Küste von Fasana bis Medolino; auch auf S. Marina (Tommasini 1872)"].

Poa annua var. remotiflora  Hack. ex Batt. & Trab., Fl. Algérie Monocot. 206. 1895. [Type: "Lieux humides et région montagneuse, Rouïba, Teniet-el-Haàd”].

Poa annua subsp. exilis  (Tomm. ex Freyn) Murb. in Asch. & Graebn., Syn. Mitteleur. Fl. 2: 389. 1900.

Poa remotiflora  (Hack. ex Batt. & Trab.) Murb., Acta Univ. Lund. 36 Afd. 2. n. 1: 22. 1900, nom. illeg., non Poa remotiflora  Rupr., Fl. Samojed. Cisural. 63. 1845.

Poa exilis  (Tomm. ex Freyn) Murb. ex Nannf., Acta Univ. Lund., ser. 2, 1(4): 73. 1906.

Poa annua  f. plicata  prostrata Sennen, Pl. Espagne n. 605. 1908, nom. nud., in sched. (MA 11165), p.p., syn. nov.

Poa annua var. plicata  Sennen, Pl. d’Espagne w.n. 1908, nom. nud., in sched. (MA 11142).

Poa annua var. laxiflora  Sennen, Pl. d’Espagne n. 606. 1908, nom. nud., in sched. (MA 11143).

Poa annua subsp. remotiflora  (Hack. ex Batt. & Trab.) Jansen & Wachter, Fl. Nederl. 1(2): 78. 1951, nom. illeg.

Poa annua L. var. spiciformis  Palau Ferrer, Pl. Baleares n. 793. 1955, nom. in sched. (GDA 30993; MA 168790), syn. nov.

Ochlopoa infirma  (Kunth) H. Scholz, Ber. Inst. Lanschafts-Pflanzenökologie Univ. Hohenheim Beih. 16: 59. 2003.

Ill. Ruiz (1991: 27, lam. I), Soreng & Peterson (2012: 14, fig. 2 F–H), Devesa (1987: 262).


"Crescit in frigidis regni Novogranatensis, inter Fontibon, Suba et Santa Fe de Bogota, alt. 1360 hexap. Floret Ausgusto". [Holotypus P-HUMB; isotypus: B-WILLD-1974 pl. 223, LE-TRIN-2638.01 fragm. & illustr., US-1851276 fragm. ex P, US-2851277 fragm. ex P-HUMB) (designated by Soreng and Peterson 2012, pg. 43)].


October to May (July).


Therophytic pastures and ruderal places, preferably in sandy soils; edaphically indifferent; 2−1000 m a.s.l.


W Europe, Mediterranean, Macaronesian and Irano-Turanian regions extending to India; introduced in Australia and the Americas. Scattered across the Iberian Peninsula and Balearic Islands. Port: AAl Ag BA BAl E Mi (R) TM. Spa.: A (Ab) Al Av B Ba (C) Ca Cc Co CR Ge Gr H Hu J (L) Lo M Ma (Mu) O (Or) (Po) PM [Mll Mn] S Sa Se Sg Te To V Va (Z) Za. For a representative list of studied materials, see Suppl. material 1.


This species is clearly differentiated from the previous one, not only by the small size of its anthers, but also by the smaller size of the leaves, which, in most cases, are not more than 2 mm wide and have margins that are barely scabrid or even smooth. Most populations comprise plants of small size (up to 22 cm).

Plants with some spikelets completely sterile and rudimentary, whitish or hyaline have been detected in some populations (e.g. province of Granada, GDA 15557).