Based on a molecular DNA phylogeny of three plastid (rpl32-trnK, rps16 intron, and rps16-trnK) and nuclear ITS regions investigating 32 species of Agrostidinae, we describe two new genera, Agrostula gen. nov. with a single species and Alpagrostis gen. nov. with four species; provide support for five species in a monophyletic Podagrostis; and include a small sample of 12 species of a monophyletic Agrostis s.s. (including the type and most species of Neoschischkinia), that separates into two clades corresponding to A. subg. Agrostis and A. subg. Vilfa. Agrostula differs from Agrostis in having leaf blades with pillars of sclerenchyma which are continuous between the adaxial and abaxial surface of the blades, dorsally rounded glumes with blunt to truncate and erose to denticulate apices, florets ½ the length of the glumes, lemmas equally wide as long, widest at (or near) apex, apices broadly truncate, irregularly 5 to 7 denticulate to erose, awnless, anthers longer than the lemmas, and rugose-papillose caryopses. Alpagrostis differs from Agrostis in having geniculate basally inserted awns and truncate lemma apices with lateral veins prolonged from the apex in (2)4 setae. The following eight new combinations are made: Agrostula truncatula, Agrostula truncatula subsp. durieui, Alpagrostis alpina, Alpagrostis alpina var. flavescens, Alpagrostis barceloi, Alpagrostis setacea, Alpagrostis setacea var. flava, and Alpagrostis schleicheri. In addition, we provide a key separating Agrostula and Alpagrostis from Agrostis s.s. and other genera previously considered as synonyms of Agrostis; lectotypify Agrostis alpina Scop., A. schleicheri Jord. & Verl., A. truncatula Parl., and A. truncatula var. durieui Henriq.; and neotypify A. setacea Curtis.

Sobre la base de una filogenia molecular de ADN de tres regiones plastidiales (rpl32-trnK, rps16 intrón y rps16-trnK) e ITS nuclear de 32 especies de Agrostidinae, describimos dos nuevos géneros, Agrostula gen. nov. con una sola especie, y Alpagrostis gen. nov. con cuatro especies; mostramos el apoyo para las cinco especies dentro de Podagrostis monofilético; e incluimos una pequeña muestra de 12 especies de Agrostis s.s (que incluye el tipo y la mayoría de las especies de Neoschischkinia), este último dividido en dos subclados que corresponden a A. subg. Agrostis y A. subg. Vilfa. Agrostula se diferencia de otras especies de Agrostis por tener láminas foliares con haces de esclerénquima continuos entre las superficies adaxial y abaxial de los limbos, glumas de dorso redondeado y ápice embotado a truncado y eroso a denticulado, antecios de ½ de la longitud de las glumas, lemas tan anchas como largas, lo más ancho en o cerca del ápice, ápices anchamente truncados, irregularmente 5 a 7 denticulados o erosos, sin arista, anteras más largas que los lemas y cariopsis rugosa-papilosa. Alpagrostis se diferencia de otras especies de Agrostis por tener aristas geniculadas insertas basalmente y ápices de lema truncados con venas laterales que se prolongan en (2)4 arístulas apicales. Presentamos las siguientes ocho nuevas combinaciones: Agrostula truncatula, Agrostula truncatula subsp. durieui, Alpagrostis alpina, Alpagrostis alpina var. flavescens, Alpagrostis barceloi, Alpagrostis setacea, Alpagrostis setacea var. flava y Alpagrostis schleicheri. Además, proporcionamos una clave que separa Agrostula y Alpagrostis de Agrostis s.s. y otros géneros previamente considerados como sinónimos de Agrostis, lectotipificamos Agrostis alpina Scop., A. schleicheri Jord. & Verl., A. truncatula Parl. y A. truncatula var. durieui Henriq. y neotipificamos A. setacea Curtis.

Agrostis, Agrostula, Alpagrostis, classification, ITS, Neoschischkinia, plastid DNA sequences, phylogeny, Podagrostis, taxonomy

The genus Agrostis L. includes ca. 224 species worldwide and is placed in subtribe Agrostidinae Fr., supersubtribe Agrostidodinae Soreng, tribe Poeae R.Br., and supertribe Poodae L. Liu in subfamily Pooideae Benth. (Soreng et al. 2017). The length of the palea was recognized by Trinius (1820, 1824) as an important character in separating species of Agrostis into two groups, those with short paleas in A. sect. Trichodium (Michx.) Trin. and those with longer paleas in A. sect. Vilfa (Adans.) Roem. & Schult. The term “Trichodium net”, based on observations of the Swedish scientist T. Vestergren, to describe the lemma epidermis of Agrostis which bear a fine-meshed network when observed under high magnification, is found almost exclusively in those species with short paleas (Björkman 1960).

A detailed review of the infrageneric classification of the Agrostis was given by Björkman (1960) and later summarized in Widén (1971), Romero García et al. (1988a), and Saarela et al. (2017). In the former Soviet Union, Tzvelev (1976, 1983) recognized four sections in the genus: Agrostis sect. Agrostis (now = A. sect. Vilfa s.s. due to type conservation of Agrostis) containing species with long paleas 1/2–2/3 the length of an usually unawned lemma; A. sect. Pentatherum (Nabel.) Tzvelev with long paleas 2/3–1 the length of a dorsally awned lemma; A. sect. Agraulus (P. Beauv.) Tzvelev with short paleas <1/3 the length of a dorsally awned lemma, and; A. sect. Trichodium (Michx.) Dumort. with paleas absent or short <1/6 the length of a usually unawned lemma. Romero García et al. (1988a, b) in the Iberian Peninsula divided Agrostis into two subgenera: A. subg. Zingrostis A.T. Romero García, G. Blanca López & C. Morales Torres containing species that have diffuse panicles with widely spreading, capillary and divaricate branches, and paleas 1/2–1 the length of an unawned lemma; and A. subg. Agrostis consisting of three sections, A. sect. Agrostis [= A. sect. Trichodium, A. sect. Agraulus (P. Beauv.) Tzvelev] with paleas <1/3 the length of the lemma; A. sect. Vilfa with paleas 1/2–2/3 the length of a usually unawned lemma; and A. sect. Aperopsis Asch. & Graeb. [= Neoschischkinia Tzvelev] with paleas <1/6 the length of the awned or unawned lemma, and an annual lifecycle.

Podagrostis (Griseb.) Scribn. & Merr. was initially described as a section of Agrostis (Grisebach 1852) and was recently updated and revised by Sylvester et al. (2019a, b, 2020) to include ten species native to the western hemisphere. Five additional species of Agrostis were transferred into Podagrostis in Sylvester et al. (2020) of which P. bacillata (Hack.) Sylvester & Soreng and P. rosei (Scribn. & Merr.) Sylvester & Soreng are newly included in our molecular analysis using nuclear internal transcribed spacer (ITS) and three plastid DNA (rpl32-trnK, rps16 intron, and rps16-trnK) markers. Previously, P. thurberiana (Hitchc.) Hultén was included in a phylogenetic study based on morphology and three plastid regions, and the taxon was weakly supported as the sister group of a strongly supported Agrostis + Polypogon Desf. clade (Soreng et al. 2007). A limitation of that analysis was that only a single species was included for each of the three genera. No molecular study has included more than two species to test the monophyly of this putative lineage (Saarela et al. 2017). The salient characters separating Podagrostis from Agrostis are: a) floret usually equaling or subequaling the glumes, sometimes slightly shorter but reaching past ¾ the length of the glumes, b) palea well-developed, usually reaching from (2/3) ¾ to almost the apex of the lemma, c) presence of a glabrous or distally hairy rachilla extension emerging from under the base of the palea as a slender short stub up to 1.4 mm long (rudimentary in most florets of P. rosei), and d) lemmas unawned or with a short straight mucro 0.2–0.6 mm long, inserted medially or in the upper half of the lemma, not surpassing the glumes (awn 1.6–2 mm long, inserted in lower 1/3 of lemma, straight or geniculate and usually not surpassing glumes in P. rosei) [Sylvester et al. 2020].

Sáez and Rosselló (2000) described Agrostis barceloi L. Sáez & Rosselló from the northern mountains of Mallorca (Balearic Islands) placing it in the Agrostis alpina Scop. complex along with A. curtisii Kerguélen and A. schleicheri Jord. & Verl. These four species share the following synapomorphies: geniculate basally inserted awns and truncate lemma apices that bare lateral setae (extension of the lateral veins) [Romero García et al. 1988a, b; Sáez and Rosselló 2000]. Other species of Agrostis with truncate lemma apices include: A. nebulosa Boiss. & Reut. [= Neoschischkinia nebulosa (Boiss. & Reut.) Tzvelev], A. reuteri Boiss., A. truncatula Parl. (these three placed in A. subg. Zingrostis), A. pourretii Willd. (placed in A. sect. Aperopsis), and A. tenerrima Trin. (placed in A. sect. Agrostis) [Romero García et al. 1988a, b].

Neoschischkinia Tzvelev (1968) initially included two species [N. elegans (Thore) Tzvelev = Agrostis tenerrima Trin., and N. nebulosa (Boiss. & Reut.) Tzvelev = Agrostis nebulosa Boiss. & Reut.] characterized by having diffuse, open panicles with divaricate and capillary branches, trapezoid lemmas with truncate apices, and caryopses with transverse furrows (Tzvelev 1968). Valdés and Scholz (2006) transferred three more species into Neoschischkinia [N. reuteri (Boiss.) Valdés & H. Scholz = A. reuteri, N. truncatula (Parl.) Valdés & H. Scholz = A. truncatula, and N. pourretii (Willd.) Valdés & H. Scholz = A. pourretii].

The main goals of this study were to estimate the phylogenetic relationships of species near or sister to Agrostis based on ITS and three plastid DNA regions (rpl32-trnK, rps16 intron, and rps16-trnK) for species of Agrostidinae and provide names for two clades that align near but not within Agrostis s.s. In addition, we provide a key separating Agrostula, gen. nov., and Alpagrostis, gen. nov., from Agrostis s.s. and other genera considered as synonyms of Agrostis. We propose lectotypes for Agrostis alpina, A. schleicheri, A. truncatula and A. truncatula var. durieui Henriq., and a neotype for A. setacea.

Our molecular sampling of five species of Podagrostis is the largest to date. In an earlier Romaschenko et al. (unpubl.) study of the three species then in the genus, P. humilis (Vasey) Björkman exhibited incongruence with the nuclear ITS signal aligning within the Podagrostis clade and the plastid signal aligning as sister to Agrostis s.s. in a grade with the Agrostis alpina–A. curtisii–A. schleicheri clade at the base. The addition of P. bacillata and P. rosei in our analysis eliminated this anomaly. In an earlier study primarily using different DNA markers with only P. aequivalvis and P. rosei (as Agrostis rosei Scribn. & Merr.), Saarela et al. (2017) found P. rosei to be part of a well-supported clade with four Chinese species of Deyeuxia Clarion ex P. Beauv. and Calamagrostis bolanderi Thurb. + P. aequivalvis. Although C. bolanderi’s placement in a strongly supported lineage with P. aequivalvis provides support for its transfer to Podagrostis, we hesitate to include it here because it may represent a separate hybrid between Podagrostis and Calamagrostis (Sylvester et al. 2020). A robust phylogeny with the inclusion of P. colombiana Sylvester & Soreng, P. exserta (Swallen) Sylvester & Soreng, P. liebmannii (E. Fourn.) Sylvester & Soreng, and P. trichodes (Kunth) Sylvester & Soreng is needed, as well as the Asian species of Deyeuxia that are allied with the group and are in need of generic realignment.

Affinities of Agrostis truncatula are unclear, given the lack of support for its position (PP = 0.52) in the phylogeny sharing a common ancestor with Calamagrostis rather than aligning within Agrostis s.l. Agrostis truncatula has many unique morphological characteristics and differs from other species of Agrostis in having the combination of perennial habit, leaf blades with pillars of sclerenchyma that are continuous between the adaxial and abaxial surface of the blades, dorsally rounded glumes with blunt to truncate and erose to denticulate apices, open and diffuse panicles, florets ½ the length of the glumes, lemmas equally wide as long, widest at (or near) apex, apices broadly truncate, irregularly 5 to 7 denticulate to erose, awnless, anthers longer than the lemmas, and rugose-papillose caryopses. We, thus, describe Agrostula gen. nov. below based on the single species, A. truncatula, with two subspecies. We find no support for recognizing Neoschischkinia (Tzvelev 1968; Valdés and Scholz 2006), since four of the five species attributed to the genus align in the Agrostis s.s. clade: A. nebulosa, A. reuteri, and A. tenerrima (type of Neoschischkinia) in Agrostis subg. Vilfa (clade B), and A. pourretii in A. subg. Agrostis (clade A); whereas A. truncatula is phylogenetically isolated from Agrostis (Agrostula). All these species exhibit unusual characteristics not commonly found within Agrostis, i.e., diffuse, open panicles with divaricate and capillary branches, trapezoid lemmas with truncate apices, and caryopses with transverse furrows. However, without molecular DNA evidence, earlier systematists could not predict the complicated phylogenetic history of Agrostula truncatula.

Our rationale for recognizing the Agrostis alpina complex in a new genus, Alpagrostis gen. nov., is straightforward. Much like Podagrostis, there are salient morphological features, i.e., geniculate basally inserted awns and truncate lemma apices with setaceous lateral veins, and there is strong clade support as sister to Agrostis s.s. The branch length of the Alpagrostis clade is moderately long indicating genetic differentiation shared among its members separating it from other clades. Sáez and Rosselló (2000) suggested that Agrostis barceloi, a tetraploid (2n = 28), is closely related to A. schleicheri, a hexaploid (2n = 42), and might have originated by the splitting of the shared ancestral lineage. The morphological features shared by A. barceloi and A. schleicheri suggest they may be derived from the diploids, A. alpina (2n = 14) or A. curtisii (2n = 14) since the former two species are geographically and genetically isolated (Sáez and Rosselló 2000). Massó et al. (2016) surveyed 40 of the 100 known individuals of the extremely narrow endemic, A. barceloi, for allozyme diversity, showing all loci to be monomorphic or with fixed heterozygosity consistent with allopolyploid origin (interspecific hybridization process and subsequent chromosome duplication) [Stebbins 1947; Crawford 1989; Soltis and Soltis 2000].

The Agrostis s.s. clade is divided into two strongly supported A and B clades that correspond to species that align in the Agrostis subg. Agrostis (clade A) or Agrostis subg. Vilfa (Adans.) Rouy (clade B) [≡ A. sect. Vilfa (Adans.) Roem. & Schult.]. As mentioned in the introduction, palea length is an important character used to separate these two subgenera and all species in clade A have paleas ≤1/3 the length of the lemma as expected, sometimes rudimentary or absent as in e.g. A. mertensii Trin., A. subpatens Hitchc. However, not all species in clade B have paleas ½–2/3 the length of the lemma since A. tenerrima has paleas 1/6 the length of the lemma and only about 0.1 mm long. This is not terribly surprising since hybrids among species of Agrostis are often fertile, and inter-subgeneric hybrids include A. canina × A. stolonifera L., a cross between the type of each subgenus of Agrostis (Widén 1971; Belanger et al. 2003; Watrud et al. 2004). In the future we intend to publish a large phylogeny of Agrostis with a comprehensive species sampling. In this larger paper we will also address the hybrid origins that complicate species relationships in Agrostis s.s. with members of Polypogon, Lachnagrostis Trin., and Chaetotropis Kunth, genera that form a clade sister to or are reticulately intermeshed within Agrostis s.s. (Saarela et al. 2017; Soreng et al. 2017: 268).

Taxonomic treatment

Agrostula P.M. Peterson, Romasch., Soreng & Sylvester, gen. nov.

urn:lsid:ipni.org:names:77212587-1

Type

Agrostis truncatula Parl.

Diagnosis

The one species of Agrostula differs from all other species of Agrostis by its glumes being dorsally rounded, not keeled, smooth throughout, and with apices blunt to truncate and erose to denticulate. Further differentiation can be made by the combination of perennial habit, leaf blades with pillars of sclerenchyma that are continuous between the adaxial and abaxial surface of the blades, panicles open and diffuse, florets ½ the length of the glumes, lemmas equally wide as long, widest at (or near) apex, apices broadly truncate, irregularly 5 to 7 denticulate to erose, awnless, paleas c. ½ the length of the lemma, anthers longer than the lemma, caryopsis surface rugose-papillose, and its ecology, being found growing in very shallow soils.

Description

Perennials moderately to densely tufted. Culms 10–40 cm tall, erect, arching, or geniculate-ascendant, slender, smooth, usually with 3 or 4 nodes extended above the basal foliage. Tillers intravaginal, extravaginal innovations absent. Leaves mostly basal, in fascicles of few to many leaves; sheaths often as long as or sometimes longer than the internodes, glabrous, smooth; ligules 0.5–4 mm long, longer than they are wide in subsp. truncatula and shorter than they are wide in subsp. durieui, oblong, hyaline, glabrous, smooth, apices truncate to acute, dentate; basal and tiller ligules 0.5–2.5 × 1–2.5 mm; upper culm ligules 3–4 × 1–2.5 mm in subsp. truncatula; blades flat, conduplicate, or convolute, straight to sometimes recurved after flowering, acute, firm to rigid, glabrous, abaxially scabrous, adaxially scabrous; blades of lower culm and tillers 3–7 cm long, 0.7–2 mm in diameter as flat, folded or rolled; blades of upper culm 1–4 cm long, 0.5–1.2 mm in diameter as flat, folded or rolled. Inflorescence c. 2–20 × 2–12 cm, a panicle, diffuse and open, broadly ovoid; panicle branches divaricate, capillaceous, with spikelets present only in the distal 1/3–½, glabrous, smooth; pedicels generally twice as long as the spikelets or longer, thickened, apices clavate, glabrous, smooth. Spikelets 1–1.7 mm long, 1-flowered, disarticulating above the glumes, dorsally compressed or very weakly laterally compressed; glumes equal or subequal, ovoid-lanceolate, membranous, 1-veined, the vein inconspicuous, dorsally rounded, smooth throughout, apices truncate to blunt and minutely notched, erose to denticulate; floret c. ½ the length of the glumes, sessile; lemmas 0.5–0.8 mm long in subsp. truncatula and (0.7–)0.9–1(–1.2) mm long in subsp. durieui, broadly ovoid, equally wide as long, widest at (or near) apex, membranous, dorsally rounded, 5-veined, veins usually evident to distinct, with at least the outer veins excurrent, usually glabrous or sometimes pubescent, smooth throughout, apex broadly truncate and denticulate, with the veins terminating in 5 to 7 teeth 1/8–1/5 the length of the lemma, awnless; paleas 0.3–0.5 mm long, c. ½ the length of the lemma, glabrous, smooth, apices bifid, denticulate; calluses rounded, blunt, glabrous or almost so, abaxially smooth; rachilla prolongation absent. Flowers perfect; lodicules 0.1–0.3 mm long, c. ½ as long as the palea, 2 in number, acute; anthers 0.7–1 mm long, 3 in number; ovaries glabrous. Caryopses 0.8–1.1 mm long, generally longer than the lemmas, only partially concealed at maturity, ellipsoid, surface rugose-papillose, ventrally sulcate, sulcus distinct, almost without rostellum; hilum narrowly elliptic c. 1/6–1/3 the length of the caryopsis; endosperm liquid. 2n = 14 + 0–4B (Garde 1951; Björkman 1960; Fernandes and Queiros 1969; Queiros 1974, 1979; Romero García and Blanca López 1988).

Distribution and ecology

Iberian Peninsula and northern Africa, distributed in France, Spain, Portugal, and Morocco. Found in Mediterranean, Iberian-Atlantic and cold temperate, often high-elevation, environments of the Pyrenees. Forms part of pioneer grassland species assemblages which grow on very shallow and sandy ‘skeleton’ soils, apparently reliant on climatic humidity in addition to precipitation for its water supply. Usually flowering from June to July.

Notes

Agrostula truncatula also differs in its leaf blade anatomy from most other species of Agrostis in having pillars of sclerenchyma which are continuous between the adaxial and abaxial surface of the blades. These continuous pillars of sclerenchyma are exceptionally thick and found only on the margins and central vein in subsp. truncatula, while subsp. durieui has thinner continuous sclerenchyma packets in the margins, central and primary veins (Romero García and Blanca López 1988: fig. 4C–F). Costal cells and intercostal long cells of the abaxial blade surface are also distinct, with A. truncatula differing from species of Agrostis in the Iberian Peninsula in having paired s₀-z cells in the costal zone, and l₃ type long cells in the intercostal zone (Romero García and Blanca López 1988). Stomata are also apparently absent on the abaxial blade surface, a character found in only a few other species in the Iberian Peninsula, i.e., Agrostis reuteri and Alpagrostis setacea (Romero García & Blanca López, 1988).

Agrostula truncatula (Parl.) P.M. Peterson, Romasch., Soreng & Sylvester, comb. nov.

urn:lsid:ipni.org:names:77212590-1

≡ Agrostis truncatula Parl., Fl. Ital. 1: 185. 1848 ≡ Neoschischkinia truncatula (Parl.) Valdés & H. Scholz, Willdenowia 36(2): 663. 2006. Type: Spain, Sierra de Guadarrama, Aug 1841, G. Reuter s.n. (lectotype, designated here: FI-016207 [image!]; isolectotypes, FI-016206 [image!], FI-012389 (Webb herbarium, left hand plant) [image!]).

Agrostula truncatula subsp. durieui (Boiss. & Reut. ex Willk.) P.M. Peterson, Romasch., Quintanar, Soreng & Sylvester, comb. nov.

urn:lsid:ipni.org:names:77212591-1

≡ Agrostis durieui Boiss. & Reut. ex Willk., Suppl. Prodr. Fl. Hisp. 15. 1893 ≡ Agrostis truncatula subsp. durieui (Boiss. & Reut. ex Willk.) Asch. & Graebn., Syn. Mitteleur. Fl. 2(1): 193. 1899 ≡ Agrostis delicatula subsp. durieui (Boiss. & Reut. ex Willk.) Rivas Mart., Lazaroa 2: 328. 1980 ≡ Neoschischkinia truncatula subsp. durieui (Boiss. & Reut. ex Willk.) Valdés and H. Scholz, Willdenowia 36(2): 663. 2006. Type: Spain. Asturias: Peñaflor [“Hab. in Asturiis freq., usque ad summa juga occident., Peñaflor”], 16 Jun 1835, M.C. Durieu de Maisonneuve s.n. [Durieu Plant. Select. Hispano-Lusit sect. 1 Asturicae. Collectae, no. 173] (lectotype, designated by A.T. Romero García and G. Blanca, Taxon 35(4): 695. 1986: P-02219803 [image!]; isolectotypes: P-03487772 [image!], W-18890096450 [image!].

= Agrostis durieui Boiss. & Reut. ex Gand., Bull. Soc. Bot. France 43: 210. 1896, nom. illeg. hom., non Boiss. and Reut. ex Willk. 1893. Type: Spain. Palencia: m. “Peña Labra, in fissuris, rupium cacuminis, 5700 ft, 26 Jul 1894, M. Gandoger s.n.” (lectotype, designated by S. Castroviejo and A. Charpin, Candollea 54(2): 475. 1999: LY [lower specimen]).

= Agrostis truncatula var. durieui Henriq., Bol. Soc. Brot. 20: 49. 1903, nom. Illeg. hom., non subsp. durieui Asch. & Graebn. Type: Spain. Asturias, 27 May 1864, Borgeau 2716. (lectotype, designated here: P-03330466 [image!]; isolectotypes: P-02220227 [image!], P-03330465 [image!], P-03487775 [image!].

= Agrostis truncatula subsp. commista Castrov. & Charpin, Candollea 38(2): 676. 1983, nom. illeg. superfl. Type: Spain. Zamora: Lubián, Chanos, proximidades del puerto de Padornelo, 29T PG 7356, 1200 m, 30 Dec [Jul] 1977, S. Castroviejo 790 (holotype: MA-242072 [image!]; isotype: G-00191448 [image!]).

Notes

Romero García et al. (1988a) provide a key to differentiate the two subspecies. The typical subspecies has ligules as long or longer than wide with acute apices, conduplicate leaf blades that recurve at anthesis, and shorter lemmas 0.5–0.8 mm long whereas Agrostula truncatula subsp. durieui has ligules wider than long with truncate apices, flat, rarely conduplicate leaf blades that do not recurve at anthesis, and longer lemmas (0.7–)0.9–1(–1.2) mm long. Portal (2009) treated subsp. durieui as Agrostis durieui for France, and did not recognize A. truncatula as being in France.

Alpagrostis P.M. Peterson, Romasch., Soreng & Sylvester, gen. nov.

urn:lsid:ipni.org:names:77212592-1

Type

Agrostis alpina Scop.

Diagnosis

The species of Alpagrostis differ from Agrostis by a combination of characters in having plants densely tufted with only intravaginal innovations, leaves mainly basal, basal leaf blades involute and setaceous or filiform, conduplicate and acute, 0.1–1.2 mm in diameter as folded or rolled, ligules longer than they are wide, spikelets generally > 3 mm long, lemma apices truncate with lateral veins prolonged from the apex in 2 (A. setacea) or 4 setae 0.1–0.5 mm long, and, crucially, and lemmas with a well-developed awn, 3–7.4 mm long, inserted basally c. 0.1–0.4 mm from the base of the lemma, conspicuously twisted and geniculate.

Description

Perennials , densely tufted. Culms 4–75 cm tall, erect or slightly geniculate at the base, slender, smooth or scabrous in the upper part, usually with 2–3 nodes extended above the basal foliage. Tillers intravaginal, extravaginal innovations absent. Leaves mostly basal, in fascicles of few to many leaves; sheaths shorter than the internodes, glabrous, smooth or scabrous; ligules 0.4–5 mm long, longer than they are wide, oblong, hyaline, glabrous, smooth, apices truncate, subacute, acute, entire to dentate; basal and tiller ligules 0.4–3 × 0.15–1.3 mm; upper culm ligules 1.7–5 × 0.7–1.5 mm; blades involute and setaceous or filiform and acute, tender to firm, straight to recurved, glabrous, abaxially smooth to scabrous, adaxially scabrous; blades of the lower culms and tillers 2–25 cm long, 0.1–1.2 mm in diameter as folded or rolled; blades of upper culm 1.5–10 cm long, 0.2–1.5 mm in diameter as folded or rolled, generally wider and shorter than tillers. Inflorescence (1.5–)2–15 × 0.5–3.5 cm, a panicle, lax and open to loosely to densely contracted and spikelike; panicle branches erect, ascendant or patent, with spikelets present from the base to only in the distal ½, glabrous, densely scabrous (or smooth in A. barceloi); pedicels as long as the spikelets, cylindrical, apices clavate, glabrous, densely scabrous (or smooth in A. barceloi). Spikelets (2.7 in A. barceloi–)3–5.2(–5.5) mm long, 1-flowered, disarticulating above the glumes, weakly laterally compressed; glumes unequal, the lower shorter and thinner than the upper, upper glume longer than the length of the floret by c. 0.8–1.9 mm, lanceolate, membranous, glabrous, keel scabrous throughout or in the distal ½, lateral veins smooth or scabrous distally, surfaces smooth or scabrous distally, apices acute or mucronate; lower glume 1-veined; upper glume (1-veined in A. barceloi) 3-veined; floret sessile, much shorter than the glumes; lemmas (1.8 in A. barceloi–)2–3.7, lanceolate, membranous, dorsally rounded, 5-veined, veins usually evident to distinct, with at least the outer veins excurrent, glabrous or thinly pubescent at the base with hairs up to 0.4 mm long, surface smooth to densely scabrous with aculeate (thin short stiff) prickles throughout, apex truncate with lateral veins prolonged from the apex in 2 (A. setacea) or 4 setae 0.1–0.5 mm long, awned with awn inserted basally c. 0.1–0.4 mm from the base of the lemma (or sometimes in the lower 1/5–1/4 in A. barceloi), awn well-developed, 3–7.4 mm long, surpassing the glumes, geniculate in roughly the middle, distinctly twisted proximally with usually at least 2 full twists below the bend, smooth proximally, scabrous distally or for most of the length; paleas 0.4–1 mm long, 1/5–1/3 the length of the lemma, glabrous, smooth, apices bifid, dentate, irregularly dentate or emarginate; calluses rounded, blunt, pilose, with hairs 0.3–0.7 mm long inserted all around or in 2 lateral tufts, abaxially smooth; rachilla prolongation absent. Flowers perfect; lodicules 0.4–0.6 mm long, ½–2/3 as long as the palea, 2 in number, acute to lanceolate; anthers 0.7–2.3 mm long, 3 in number; ovaries glabrous. Caryopses 1.7–2 mm long, shorter than the lemmas, concealed at maturity, ellipsoid or fusiform, surface smooth (becoming narrow and shriveled with age), ventrally sulcate, sulcus distinct, almost without rostellum; hilum 1/6–1/3 length of the caryopsis, narrowly elliptic; endosperm liquid. 2n = 14 (In A. setacea, A. alpina), 28 (A. barceloi), or 42 (A. schleicheri) [Frey 1997; Sáez and Rosselló 2000].

Distribution and ecology

Europe and Mediterranean. Found in cold temperate, often high-elevation environments, often found growing on nutrient poor soils. Usually flowering from June to August.

Notes

All caryopses examined from herbarium specimens had a liquid lipid endosperm or were shriveled with a deep sulcus, implying that fresher specimens likely had a liquid endosperm. Agrostis sect. Bromidium (Nees & Meyen) E. Desv. shares many characteristics with Alpagrostis, such as lemma apices terminating in scabrous setae, well-developed, thickened, twisted and geniculate awns inserted in the lower 1/3 of the lemma, palea < 1/3 the length of the lemma, caryopses with liquid to semi-liquid endosperm. Based on molecular DNA studies, Romaschenko et al. (unpubl.) and Tkach et al. (2020) found Bromidium to align within Agrostis s.s.

Alpagrostis barceloi differs somewhat from the other species in the genus, in terms of the panicle branches and pedicels being smooth, spikelets sometimes being shorter, 1-veined upper glumes, and awn sometimes inserted slightly higher up the lemma.

Alpagrostis alpina (Scop.) P.M. Peterson, Romasch., Soreng & Sylvester, comb. nov.

urn:lsid:ipni.org:names:77212593-1

≡ Agrostis alpina Scop., Fl. Carniol. ed. 2, 1: 60. 1772 ≡ Agraulus alpinus (Scop.) P. Beauv., Ess. Agrostogr.: 5. 1812 ≡ Agrestis alpina (Scop.) Bubani, Fl. Pyren. 4: 287. 1901. Type: “Habitat in Alpibus Vochinensibus” and “HALL Hist. n. 1477”, SCHEUCHZ. Gram pag. 140, Prodr. P. 22, tab. 4, fig. 1.”, original material: In siccioribus Alpium Helveticarum & Rhaeticarum pratis, J. Scheuchzer s.n. (lectotype, designated here: W-18890240472 [image!]. fig. 2

Alpagrostis alpina var. flavescens (Honck.) P.M. Peterson, Romasch., Soreng & Sylvester, comb. nov.

urn:lsid:ipni.org:names:77212596-1

≡ Aira flavescens Honck., Gew.: 212. 1782 ≡ Avena aurata All., Fl. Pedem. 2: 255. 1785, nom. nov. (non Avena flavescens L.) ≡ Agrostis aurata (All.) Suter, Fl. Helv. 1: 61. 1802, nom. superfl. ≡ Agrostis flavescens (Honck.) Host, Icon. Descr. Gram. Austriac. 4: 52. 1809 ≡ Agrostis rupestris var. aurata (All.) Clairv., Man. Herbor. Suisse: 16. 1811 ≡ Avena rupestris var. aurata (All.) Clairv., Man. Herbor. Suisse: 16. 1811 ≡ Trichodium flavescens (Host) Schult., Oestr. Fl., ed. 2, 1: 165. 1814 ≡ Agraulus flavescens (Host) Sweet, Hort. Brit., ed. 2: 556. 1830 ≡ Agrostis alpina var. flavescens (Honck.) Schrad., in Schlechtendal, Linnaea 12: 435. 1838 ≡ Agrostis alpina var. aurata (All.) Ducommun, Taschenb. Schweiz. Bot.: 852. 1869 ≡ Agrostis alpina f. aurata (All.) Beldie, Fl. Reipubl. Popularis Sin. 12: 163. 1972. Type: Switzerland. Bagnes A. Haller hist. 1488 [a description] (lectotype needed).

Alpagrostis barceloi (L. Sáez & Rosselló) P.M. Peterson, Romasch., Soreng & Sylvester, comb. nov.

urn:lsid:ipni.org:names:77212597-1

≡ Agrostis barceloi L. Saéz & Rosselló, Bot. J. Linn. Soc. 133: 361–365, f. 1. 2000. Type: Spain. Insulae Balearicae [Balearic Islands], Majorca, in praeruptis rupium umbrosis calcareis septentrionalibus loco dicto Puig Major de Son Torrella, 1400 m, 31SDE8206, 14 Aug 1998, L. Sáez 5132 (holotype: BC-852322; isotypes: BCC, M, W-20040000640 [image!], herb. L. Sáez).

Notes

This species is included in Alpagrostis based on its similar morphology, although this needs to be confirmed in molecular analyses. Certain characteristics sometimes differ from the other species in the genus, i.e., spikelets and lemmas sometimes shorter, insertion of the awn sometimes higher on the lemma, panicle branches and pedicels smooth or scaberulous. Alpagrostis barceloi shares with other member of the genus, conduplicate leaf blades, truncate lemma apices with setaceous extensions of the lateral veins, and ecologically is a strict orophyte, much like A. alpina and A. schleicheri (Sáez and Rosselló 2000).

Alpagrostis setacea (Poir.) P.M. Peterson, Romasch., Soreng & Sylvester, comb. nov.

urn:lsid:ipni.org:names:77212601-1

≡ Agrostis setacea Curtis, Pract. Obs. Brit. Grasses ed. 1: 35, no. 4. post (Aug) 1787, nom. illeg. hom. (non Villars (Feb) 1787) ≡ Agrostis setacea Curtis, Fl. Londin. 6, t. 12. 1798 ≡ Agrostis rupestris var. setacea Poir. in Lam., Encycl., Suppl. 1: 247. 1810 ≡ Vilfa setacea (Poir.) P. Beauv., Ess. Agrostogr.: 16. 148. 1812 ≡ Trichodium setaceum (Poir.) Roem. & Schult., Syst. Veg. ed. 15 bis, 2: 280. 1817 ≡ Agraulus setaceus (Poir.) Gray, Nat. Arr. Brit. Pl. 2: 149. 1821 [1822] ≡ Agrestis setacea (Poir.) Bubani, Fl. Pyren. 4: 286. 1901 ≡ Agrostis curtisii Kerguélen, Lejeunia, n.s., 75 (Err. & Corr.): 1. 1975 ≡ Agrostis curtisii Kerguélen, Lejeunia, n.s., 75 (Err. & Corr.): 1. 1975. Type: England. Curtis’s garden [Sowerby’s Herbarium], (neotype, designated here: BM-001144085 [image!]). fig. 3A.

Notes

Philipson (1937) mentions “No authentic specimens of Curtis have been preserved. There is one specimen in the British Museum Herbarium, originally from “Curtis’s garden” (BM-001144085), which may be taken as representative of the species.” Philipson was possibly referring to this specimen. On the neotype there are three different collections on the same sheet. The specimen on the upper left of the sheet is BM-001144085 (Fig. 2A).

Figure 2. 

Alpagrostis alpina A, D spikelets B caryopsis C floret E floret, showing dorsal surface. Plant fragments taken from Sain-Lager 3 (US-1628154).

Alpagrostis setacea var. flava (Des Moul.) P.M. Peterson, Romasch., Soreng & Sylvester, comb. nov.

urn:lsid:ipni.org:names:77212602-1

≡ Agrostis setacea var. flava Des Moul., Actes Soc. Linn. Bordeaux 11: 320. 1840 ≡ Agrostis curtisii var. flava (Des Moul.) Portal, Agrostis de France: 193. 2009. Type: France. Dans les bois découverts, les bruyères et les landes rases, aux environs de Sagonzac (Périgord), 26 May 1838, M.C. Durieu de Maisonneuve #90bis (holotype: not found; isotypes: MPU-027078 [image!], MP-027079 [image!], W-18890240353 [image!], W-18890240354 [image!]).

Alpagrostis schleicheri (Jord. & Verl.) P.M. Peterson, Romasch., Soreng & Sylvester, comb. nov.

urn:lsid:ipni.org:names:77212600-1

≡ Agrostis schleicheri Jord. & Verl., Arch. Fl. France Allemagne 1: 347, 346–348. 1855 ≡ Trichodium schleicheri (Jord. & Verl.) Fourr., Ann. Soc. Linn. Lyon, n.s., 17: 181. 1869 ≡ Agrostis subspicata Arv.-Touv., Essai Pl. Dauphiné: 67. 1871, nom. illeg. superfl. ≡ Agrostis alpina proles schleicheri (Jord. & Verl.) Asch. & Graebn., Syn. Mitteleur. Fl. 2(1): 187. 1899 ≡ Agrestis schleicheri (Jord. & Verl.) Bubani, Fl. Pyren. 4: 288. 1901 ≡ Agrostis alpina subsp. schleicheri (Jord. & Verl.) Rouy, in G. Rouy & J. Foucaud, Fl. France 14: 69. 1913. Type: France. Débris mouvants des rochers calcaries de Mt. St-Nizier près de Grenoble (Isère), 15 Jul 1854, Jean-Baptiste Verlot 1584 (lectotype, designated here: P-03161255 [image!], isolectotypes: BM-001134099 [image!], BM-001134098 [image!], MPU-027081 p.p. Verlot 1584 [image!], MPU-027082 [no image], P-03656627 [image!]).

Notes

Jordon (1855) cited the following five collections: the Jura sur le Reculet (Ain), and Mont Ventoux, in August 1841, A. Jordan; Mt. St-Nizier near Grenoble, Verlot; Bex (canton of Vaud), E. Thomas; Mt. St-Nizier near Grenoble, Clement. Also cited is a report of Reuter of his collection from Jura sur le Reculet [P-03161256, image!], and Agrostis filiformis sensu Vill. We select The Verlot 1584 specimen as there are several duplicates, and P-03161255 as the lectotype because that sheet is not mounted with any other collection as the MPU and BM sheets seem to be.

Figure 3. 

Neotype of Agrostis setacea Curtis [= Alpagrostis setacea (Poir.) P.M. Peterson, Romasch., Soreng & Sylvester] from Curtis’s garden (BM-001144085), upper left hand specimen indicated by A.

We thank Flora iberica project (CGL2014–52787–C3–1–P, CGL2012–32914, CGL201785204-C3-1-P), and FPI fellowship BES-2012-053754 to P. Barberá; the National Geographic Society Committee for Research and Exploration (Grant No. 8848-10, 8087-06) for field and laboratory support; the Smithsonian Institution’s Restricted Endowments Fund, the Scholarly Studies Program, Research Opportunities, Atherton Seidell Foundation, Biodiversity Surveys and Inventories Program, Small Grants Program, the Laboratory of Analytical Biology, and the United States Department of Agriculture. We thank Jeffery M. Saarela, Kanchi N. Gandhi and Francisco Máquez-García for suggesting changes to the manuscript.