Research Article |
Corresponding author: Paul M. Peterson ( peterson@si.edu ) Academic editor: Marcin Nobis
© 2020 Paul M. Peterson, Steven P. Sylvester, Konstantin Romaschenko, Robert J. Soreng, Patricia Barberá, Alejandro Quintanar, Carlos Aedo.
This is an open access article distributed under the terms of the CC0 Public Domain Dedication.
Citation:
Peterson PM, Sylvester SP, Romaschenko K, Soreng RJ, Barberá P, Quintanar A, Aedo C (2020) A phylogeny of species near Agrostis supporting the recognition of two new genera, Agrostula and Alpagrostis (Poaceae, Pooideae, Agrostidinae) from Europe. PhytoKeys 167: 57-82. https://doi.org/10.3897/phytokeys.167.55171
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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. (
A detailed review of the infrageneric classification of the Agrostis was given by
Podagrostis (Griseb.) Scribn. & Merr. was initially described as a section of Agrostis (
Neoschischkinia
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.
Detailed methods for DNA extraction, amplification, and sequencing are given in
Taxon voucher (collector, number, and where the specimen is housed), country of origin, and GenBank accession for DNA sequences of rps16-trnK, rps16 intron, rpl32-trnL, and ITS regions; a dash (–) indicates missing data.
Taxa | Voucher | Country | rps16-trnK | rps16 intron | rpl32-trnL | ITS | |
---|---|---|---|---|---|---|---|
1 | Agrostis alpina Scop. [= Alpagrostis alpina (Scop.) P.M. Peterson, Romasch., Soreng & Sylvester] | Soreng 7484, Gillespie & Peterson (US) | Austria, Niederosterrich | MT410018 | – | MT409931 | MT396529 |
2 | Agrostis bacillata Hack. [= Podagrostis bacillata (Hack.) Sylvester & Soreng] | Evans 145, Lellinger & Bowers (US) | Costa Rica, San Jose | MT410019 | MT409978 | MT409932 | MT396530 |
3 | Agrostis balansae (Boiss.) Tzvelev | Soreng 8967b & Cabi (US) | Turkey, Erzurum | MT410020 | MT409979 | MT409933 | MT396531 |
4 | Agrostis canina L. | Herrero 1874, Aedo, Aizpuru, Alarcón, Aldasoro, Castroviejo, Conti, Estébanez, Güemes, Guillén, Navarro, Pedrol, Prunell, Rico, Rodríguez Gracia & Tinti (MA) | Italy, Abruzzo | MT410021 | MT409980 | MT409934 | MT396532 |
5 | Agrostis capillaris L. | Aedo 19209 (MA) | France, Landes | MT410022 | MT409981 | MT409935 | MT396533 |
6 | Agrostis curtisii Kerguélen [= Alpagrostis setacea (Poir.) P.M. Peterson, Romasch., Soreng & Sylvester] | Gil s.n. (MA) | Spain, Coruña | MT410023 | MT409982 | MT409936 | MT396534 |
7 | Agrostis curtisii Kerguélen [= Alpagrostis setacea (Poir.) P.M. Peterson, Romasch., Soreng & Sylvester] | Louzan s.n. & Rodríguez-Oubiña (MA) | Spain, Coruña | MT410024 | MT409983 | MT409937 | MT396535 |
8 | Agrostis mertensii Trin. | Smith 1288 (US) | Sweden, Härjedalen | MT410025 | MT409984 | MT409938 | MT396536 |
9 | Agrostis micrantha Steud. | Tibet-MacArthur 1516, Wen, Nie, Soreng, Rankin, Yue, Wang & Yue (US) | China, Yunnan | MT410026 | MT409985 | MT409939 | MT396537 |
10 | Agrostis nebulosa Boiss. & Reut. | Serra 8114 (US) | Spain | MT410027 | MT409986 | MT409940 | MT396538 |
11 | Agrostis nervosa Nees ex Trin. | Soreng 5276, Peterson & Sun Hang (US) | China, Yunnan | MT410028 | MT409987 | MT409941 | MT396539 |
12 | Agrostis pourretii Willd. | Carrera s.n. (MA) | Spain | MT410029 | MT409988 | MT409942 | MT396540 |
13 | Agrostis reuteri Boiss. | Escobar-García s.n. (MA) | Spain | MT410030 | MT409989 | MT409943 | MT396541 |
14 | Agrostis rosei Scribn. & Merr. [= Podagrostis rosei (Scribn. & Merr.) Sylvester & Soreng] | Peterson 19053 & Sánchez Alvarado (US) | Mexico, Durango | MT410031 | MT409990 | MT409944 | MT396542 |
15 | Agrostis schleicheri Jord. & Verl. [= Alpagrostis schleicheri (Jord. & Verl.) P.M. Peterson, Romasch., Soreng & Sylvester] | Arán 5627, Patino & Valencia (MA) | Spain, Cantabria | MT410032 | MT409991 | MT409945 | MT396543 |
16 | Agrostis subpatens Hitchc. | Lathrop 5571 (US) | Costa Rica | MT410033 | MT409992 | MT409946 | MT396544 |
17 | Agrostis trachyphylla Pilg. | Peterson 24374, Soreng & Romaschenko (US) | Tanzania, Kilimanjaro | MT410034 | MT409993 | MT409947 | MT396545 |
18 | Agrostis truncatula Parl. [= Agrostula truncatula (Parl.) P.M. Peterson, Romasch., Soreng & Sylvester] | Barberá 916 (MA) | Spain | MT410035 | MT409994 | MT409948 | MT396546 |
19 | Agrostis truncatula Parl. [= Agrostula truncatula (Parl.) P.M. Peterson, Romasch., Soreng & Sylvester] | García Río (MA) | Spain, Ciudad Real | MT410036 | MT409995 | MT409949 | MT396547 |
20 | Agrostis truncatula Parl. [= Agrostula truncatula (Parl.) P.M. Peterson, Romasch., Soreng & Sylvester] | Morales 2470 (MA) | Spain | MT410037 | MT409996 | MT409950 | MT396548 |
21 | Calamagrostis canescens (Weber ex F.H. Wigg.) Roth | Barta 1999-14 (MA) | Austria, Niederösterreich | MT410038 | MT409997 | MT409951 | MT396549 |
22 | Calamagrostis crassiglumis Thurb. | Howell 23214 (US) | USA | MT410039 | MT409998 | MT409952 | MT396550 |
23 | Calamagrostis epigeios (L.) Roth | Calvo 4970 (MA) | Czech Republic, South Bohemian | MT410040 | MT409999 | MT409953 | MT396551 |
24 | Calamagrostis lahulensis G. Singh | Tibet-MacArthur 1317 (US) | China | MT410041 | MT410000 | MT409954 | MT396552 |
25 | Calamagrostis macrolepis Litv. | Soreng 7637, Johnson, Shuvalov, Chapurin, Samsaliev & Samsaliev (US) | Kyrgyzstan, Naryn | MT410042 | MT410001 | MT409955 | MT396553 |
26 | Calamagrostis pseudophragmites (Haller fil.) Koeler | Cabezas 688, Aedo, Calvo, Castroviejo, Constantidinis, Gonzalo, Güemes, Herrero, Karidas, Medina, Navarro, Pedrol, Prunell, Quintanar, Rico & Rodríguez Gracia (MA) | Greece, Epiro | MT410043 | MT410002 | MT409956 | MT396554 |
27 | Calamagrostis stricta (Timm) Koeler | Soreng 7722, Johnson, Shuvalov, Chapurin, Samsaliev & Samsaliev (US) | Kyrgyzstan, Chu | MT410044 | MT410003 | MT409957 | MT396555 |
28 | Chascolytrum rufum J. Presl | Butzke 11180 (US) | Brazil | – | – | MT409958 | MT396556 |
29 | Chascolytrum rufum J. Presl | Wasum 1178 (US) | Brazil, Rio Grande do Sul | – | – | MT409959 | MT396557 |
30 | Chascolytrum subaristatum (Lam.) Desv. | Hale 20420 & Soderstrom (US) | Mexico, Chiapas | MT410045 | MT410004 | MT409960 | MT396558 |
31 | Echinopogon caespitosus C.E. Hubb. | Craven 672 (NSW) | Australia, New South Wales | MT410046 | MT410005 | MT409961 | MT396559 |
32 | Gastridium phleoides (Nees & Meyen) C.E. Hubb. | Thomas 9650 (US) | USA | MT410048 | MT410007 | MT409963 | MT396561 |
33 | Gastridium phleoides (Nees & Meyen) C.E. Hubb. | Chase A. 5727 (US) | USA | MT410047 | MT410006 | MT409962 | MT396560 |
34 | Gastridium phleoides (Nees & Meyen) C.E. Hubb. | Gander 8198 (US) | USA | MT410049 | MT410008 | MT409964 | MT396562 |
35 | Gastridium ventricosum (Gouan) Schinz & Thell. | Wood 14625 (US) | USA Hawaii, Kaua`i | MT410050 | MT410009 | MT409965 | MT396563 |
36 | Podagrostis aequivalvis (Trin.) Scribn. & Merr. | Eastham 10895 (US) | Canada, British Columbia | – | – | MT409966 | MT396564 |
37 | Podagrostis aequivalvis (Trin.) Scribn. & Merr. | Spellenberg 1574 & Spellenberg (US) | Canada, Alberni-Clayoquot | – | – | MT409967 | MT396565 |
38 | Podagrostis humilis (Vasey) Björkman | Harrison 10038 (US) | USA, Utah | – | – | MT409968 | MT396566 |
39 | Podagrostis humilis (Vasey) Björkman | Nielsen 6612 (US) | USA, Utah | – | – | MT409969 | MT396567 |
40 | Podagrostis thurberiana (Hitchc.) Hultén | Crampton 3860 (US) | USA, California | – | – | – | MT396568 |
41 | Podagrostis thurberiana (Hitchc.) Hultén | Davis 2949 (US) | USA, Idaho | MT410051 | MT410010 | MT409970 | MT396569 |
42 | Podagrostis thurberiana (Hitchc.) Hultén | Peterson 19755, Saarela & Sears (US) | USA, California | MT410052 | MT410011 | MT409971 | MT396570 |
43 | Podagrostis thurberiana (Hitchc.) Hultén | Soreng 7419 & Soreng (US) | USA, California | MT410053 | MT410012 | MT409972 | MT396571 |
44 | Podagrostis thurberiana (Hitchc.) Hultén | Terrell 4204 (US) | USA, California | MT410054 | MT410013 | MT409973 | MT396572 |
45 | Triplachne nitens (Guss.) Link | Aedo 12786 (MA) | Spain, Murcia | MT410055 | MT410014 | MT409974 | MT396573 |
46 | Triplachne nitens (Guss.) Link | López Jiménez 1241 & García Tapia (MA) | Morocco, Nador | MT410056 | MT410015 | MT409975 | MT396574 |
47 | Triplachne nitens (Guss.) Link | Rivas Martínez, Costa & Regueiro (MA) | Spain, Islas Baleares | MT410057 | MT410016 | MT409976 | MT396575 |
48 | Triplachne nitens (Guss.) Link | Sanz Fábregas s.n. (MA) | Spain, Almeria | MT410058 | MT410017 | MT409977 | MT396576 |
It is critically important to include the type species of genera and other higher taxa when doing molecular studies to know you are using the name correctly as intended by the original author. The following species are the types of their respective genera and are included in our analyses: Agrostis canina L. (type conserved), Calamagrostis canescens (Weber) Roth, Chascolytrum subaristatum (Lam.) Desv., Gastridium ventricosum (Gouan) Schinz & Thell., Neoschischkinia elegans (= Agrostis tenerrima), Podagrostis aequivalvis Trin., and Triplachne nitens (Guss.) Link.
Our study was designed to test relationships of three of the four species (A. alpina, A. curtisii, and A. schleicheri) of the Agrostis alpina group, all five species that have been attributed to Neoschischkinia (N. elegans, N. nebulosa, N. pourretii, N. reuteri, and N. truncatula), Podagrostis, Gastridium P. Beauv., Triplachne Link, and representative samples of Agrostis, Calamagrostis Adans., and Chascolytrum Desv. All of these genera have been found in a clade in previous molecular analyses and in our unpublished trees investigating a large number of species in Agrostis, Calamagrostis, Cinnagrostis Griseb., and Koeleria Pers. (
Herbarium acronyms follow Index Herbariorum (Thiers, continuously updated). In this treatment glabrous means without pubescence (in the sense of slender, relatively soft hairs). Smooth indicates no prickle-hairs with broad bases and/or hooked or pointed apices (i.e., pubescence can occur on a smooth surface, and a rough or scabrous surface can be glabrous). Specimens in the United States National Herbarium (US) and the Real Jardín Botánico Herbarium (MA) were reviewed for this study, in addition to
A total of 176 new sequences from 33 species (48 individuals) are reported in GenBank (Table
Characteristics of rps16-trnK, rps16 intron, rpl32-trnL, and ITS, and parameters used in Bayesian analyses indicated by Akaike Information Criterion (AIC).
rps16-trnK | rps16 intron | rpl32-trnL | Combined plastid data | ITS | Overall | |
Total aligned characters | 738 | 845 | 904 | 2487 | 712 | 3199 |
Number of sequences | 41 | 40 | 47 | 128 | 48 | 176 |
Likelihood score (-lnL) | 1259.16 | 1449.21 | 1888.70 | 1989.55 | ||
Number of substitution types | 6 | 6 | 6 | – | 6 | – |
Model for among-sites rate variation | gamma | gamma | gamma | – | gamma | – |
Substitution rates | ||||||
rAC | 2.44683 | 2.33760 | 1.03926 | – | 0.78611 | – |
rAG | 2.12801 | 1.84060 | 0.64852 | 2.03233 | ||
rAT | 0.11415 | 0.31850 | 0.20833 | 1.27811 | ||
rCG | 1.41016 | 0.78529 | 0.73967 | 0.31482 | ||
rCT | 2.47892 | 2.54521 | 0.97480 | 5.07499 | ||
rGT | 1.00000 | 1.00000 | 1.00000 | 1.00000 | ||
Character state frequencies | ||||||
fA | 0.28602 | 0.35597 | 0.36767 | – | 0.22141 | – |
fC | 0.16385 | 0.15120 | 0.14893 | 0.29792 | ||
fG | 0.16537 | 0.18750 | 0.13618 | 0.29123 | ||
fT | 0.38477 | 0.30534 | 0.34722 | 0.18944 | ||
Proportion of invariable sites | 0.37013 | 0.1041 | 0.36504 | – | 0.30563 | – |
Substitution model | TVM+G | GTR+I+G | GTR+G | – | GTR+I+G | – |
Gamma shape parameter (α) | 0.90138 | 0.45913 | 0.83500 | – | 0.38018 | – |
Maximum-likelihood tree inferred from combined plastid (rpl32-trnL, rps16 intron, rps16-trnK) and ITS sequences. Numbers above the branches are posterior probabilities; numbers below the branches are bootstrap values; accessions marked with an asterisk* were formerly included in Neoschischkinia; and letters refer to clade A = Agrostis subg. Agrostis and clade B = A. subg. Vilfa. Scale bar: 0.002 substitutions per site.
The ML tree from the combined plastid and ITS regions (Fig.
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.),
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 (
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.
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 (
Agrostis truncatula Parl.
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.
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 (
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.
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 (
≡ 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!]).
≡ 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 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!]).
Agrostis alpina Scop.
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.
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) [
Europe and Mediterranean. Found in cold temperate, often high-elevation environments, often found growing on nutrient poor soils. Usually flowering from June to August.
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
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.
≡ 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
≡ 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).
≡ 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).
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 (
≡ 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.
≡ 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!]).
≡ 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!]).
1 | Spikelets disarticulating below the glumes, the glumes, floret, and part of the pedicel falling together as a unit; glume apices lanceolate or lanceolate-subulate, muticous, mucronate or awned; palea < ½ the length of the lemma | Polypogon Desf. |
– | Spikelets disarticulating above the glumes, the glumes remaining on the inflorescence after the florets have fallen; glumes acute to acuminate, not awned; palea of varying length, absent or rudimentary to equaling the length of the lemma | 2 |
2 | Rachilla extension present (cases where it is sometimes rudimentary key both ways), of varying lengths (sometimes very short, and requiring the base of the palea checked closely to distinguish the structure from hairs), glabrous or pilulose to densely pilose; palea well-developed, generally > 2/3 the length of the lemma | 3 |
– | Rachilla extension absent; palea of varying length | 4 |
3 | Lemmas densely pubescent, with rigid and abundant hairs; callus and rachilla notably hairy; lemmas with a well-developed usually geniculate and twisted awn, > 1 mm long, inserted in the lower or upper half of the lemma, clearly exceeding the glumes; taxa from southern Hemisphere (Australia, Malaysia, New Zealand, South Africa and South America) | Lachnagrostis Trin. |
– | Lemmas glabrous; callus and rachilla glabrous or with short hairs emerging from only the rachilla apex and the basal side-ridges of the callus; lemmas unawned or with a short straight awn, usually < 0.5 mm long, inserted in the upper half of the lemma, not or barely exceeding the glumes (awn well-developed, 1.6–2 mm long, inserted in lower 1/3 of lemma, straight or geniculate and usually not surpassing glumes in Podagrostis rosei (Scribn. & Merr.) Sylvester & Soreng, but then callus and rachilla glabrous, rachilla very short, < 0.3 mm long, glabrous, plants from Mexico); taxa from North, Central and South America | Podagrostis (Griseb.) Scribn. & Merr. (in part) |
4 | Lemma apex terminating in 2 or 4 scabrous setae 0.1–2 mm long; lemma with a well-developed geniculate and twisted awn inserted basally or in the lower 1/3 and surpassing the glumes; paleas < 1/3 the length of the lemma; calluses pilulose or densely tufted; leaf blades often filiform or involute; lemma surfaces pilose (Bromidium) or usually glabrous (Alpagrostis); caryopses with liquid endosperm becoming narrow and shriveled with age | 5 |
– | Lemma apex entire or finely dentate with short teeth at the end of each lateral vein; lemmas muticous, with a straight mucron 0.2–1 mm long, or with a long geniculate and twisted awn to 6+ mm long, inserted in the lower, middle or upper 1/3 of the lemma but usually not basally, not surpassing to greatly surpassing the glumes; lemma surface usually glabrous (sometimes pilose e.g. Agrostis castellana L.); calluses usually glabrous or with hairs restricted to lateral lines continuous with the basal lemma margins; leaf blades of various forms but less often filiform or involute; caryopsis usually rounded, with hardened endosperm, less often with liquid endosperm | 6 |
5 | Anthers 0.2–0.7 mm long; lemma surface often pilose; awn inserted in the lower 1/3 but usually not basally; longest setae of lemma apex 0.4–2 mm long; caryopsis thin or with liquid endosperm; leaf blades filiform or flat, generally 1–4 mm diam.; annuals from southern South America | Agrostis sect. Bromidium (Nees & Meyen) E. Desv. |
– | Anthers 0.7–2.3 mm long; lemma surface usually glabrous or pilulose basally; longest setae of lemma apex 0.1–0.5 mm long; awn inserted basally; leaf blades filiform or involute, 0.1–1.5 mm diam. as folded or rolled; perennials of Europe and NW Africa | Alpagrostis P.M. Peterson, Romasch., Soreng & Sylvester |
6 | Floret equaling or subequaling the glumes, sometimes slightly shorter but reaching past ¾ the length of the glumes, usually with a short rachilla prolongation emerging behind the palea (sometimes absent in many florets of P. rosei and P. humilis so check many spikelets); paleas well-developed, usually reaching from (2/3) ¾ to almost the apex of the lemma; lemmas muticous or with a short straight awn 0.2–0.6 mm long, inserted medially or in the upper half of the lemma, not surpassing the glumes (awn well-developed, 1.6–2 mm long, inserted in lower 1/3 of lemma, straight or geniculate and usually not surpassing glumes in P. rosei) | Podagrostis (Griseb.) Scribn. & Merr. (in part) |
– | Floret notably shorter than the glumes, usually 1/3–3/4 the length of the glumes, rarely longer, without a trace of a rachilla prolongation; paleas well-developed, poorly-developed, or absent, when well-developed reaching from ½–¾ the length of the lemma; lemmas muticous, with a short straight awn 0.2–1 mm long, or with a long geniculate and twisted awn to 6+ mm long, inserted basally, medially or in the upper half of the lemma, not surpassing to greatly surpassing the glumes | 7 |
7 | Glumes dorsally rounded, not keeled, smooth throughout, apices blunt to truncate and erose to denticulate; palea c. ½ the length of the lemma; panicles open and diffuse; 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 lemma, caryopsis surface rugose-papillose; perennials; growing from very shallow soils; from the Iberian Peninsula and Northern Africa | Agrostula P.M. Peterson, Romasch., Soreng & Sylvester |
– | Glumes keeled, usually scabrous (at least in part), rarely upper glume smooth throughout, apices obtuse to acute-acuminate, rarely blunt to truncate, rounded to muticous; palea absent or rudimentary to ¾ the length of the lemma; panicles open and diffuse to condensed and spikelike; lemmas usually longer than wide (rarely equally wide as long), usually narrowed towards the apex, apices variable, ranging from somewhat broadly to usually narrowly truncate, usually with 2 to 5 dents (sometimes aristulate), to blunt and entire, awnless or with an awn 0.2–6+ mm long; anthers sometimes longer to usually shorter than the lemma; caryopsis surface usually smooth; perennials or annuals; usually growing from well-developed soils, less often from shallow soils, and generally reliant on soil moisture for their water supply; cosmopolitan | Agrostis L. |
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.