Agrostis scabra Willd., Sp. Pl. 1(1): 370. 1797.

Vigosa-Mercado, J. Luis, Delgado-Salinas, Alfonso, Alvarado Cardenas, Leonardo O. & Eguiarte, Luis E., 2023, Revision of the genus Agrostis (Poaceae, Pooideae, Poeae) in Megamexico, PhytoKeys 230, pp. 157-256 : 157

14. Agrostis scabra Willd., Sp. Pl. 1(1): 370. 1797.

Figs 4M , 29 , 30A

= Trichodium laxiflorum Michx., Fl. Bor. Amer. 1: 42. 1803, nom. illeg. superfl. Agrostis laxa Schreb. ex Pursh, Fl. Amer. Sept. 1: 61. 1814 [1813], pro syn. Agrostis laxiflora (Michx.) Richardson, Narr. Journey Polar Sea: 731. 1823, nom. illeg. hom., non Poir., 1810. Agrostis michauxii Zuccagni var. laxiflora A. Gray, N. Amer. Gram. 1: 17. 1834. Agrostis hyemalis (Walter) Britton, Sterns & Poggenb. var. Agrostis hyemalis laxiflora (Michx.) Beetle, Phytologia 52: 11. 1982. Type. USA. Hab. In humidis et praetensibus a sinu Hudsonis ad Floridam, A. Michaux s.n. (holotype: P).

Trichodium scabrum (Willd.) Muhl., Cat. Pl. Amer. Sept. 10. 1813.

= Agrostis geminata Trin., Gram. Unifl. Sesquifl. 207. 1824. Agrostis hyemalis (Walter) Britton, Sterns & Poggenb. var. Agrostis geminata geminata (Trin.) Hitchc., U.S.D.A. Bur. Pl. Industr. Bull. 68: 44. 1905. Agrostis scabra Willd. var. geminata (Trin.) Swallen, Proc. Biol. Soc. Washington 54: 45. 1941. Agrostis scabra Willd. var. geminata (Trin.) Hultén, Fl. Alaska Yukon 2: 156. 1942, nom. illeg. hom. Type: USA. Alaska: Unalaschka, J.F. Eschschholtz s.n. (holotype: LE-TRIN (LE01026091 [image!]); isotypes: LE-TRIN (LE00009321 [image!]), US [fragm. ex LE-TRIN] (US00156432 [image!])).

Agrostis laxiflora (Michx.) Richardson var. scabra (Willd.) Torr., Fl. New York 2: 442. 1843.

Agrostis hyemalis (Walter) Britton, Sterns & Poggenb. var. Agrostis hyemalis scabra (Willd.) H.L. Blomq., Grass. North Carolina 82. 1948.*

Type.

America borealis, Anonymous s.n. (lectotype, designated by Vigosa-Mercado (2022a: 3): B-W (BW01732020 [image!]); isolectotype: B-W (BW01732010 [image!])).

Description.

Plants perennial, caespitose. Tillers extravaginal, with cataphylls. Culms 15-90 cm long, erect, nodes usually 1-2(-3), sometimes more, glabrous, internodes glabrous. Leaves mostly basal, sometimes cauline leaves well developed; sheaths 1.5-13 cm long, the lower ones usually longer than the internodes, the upper ones shorter, glabrous or scaberulous; ligules 0.5-5 mm long, usually longer than wide, dorsally scaberulous, apices rounded to truncate, sometimes acute, erose to lacerate; blades 3-14 cm long, (0.3-)0.5-2(-3) mm wide, the lower ones usually filiform and involute, the upper ones linear and flat, scaberulous on both surfaces. Panicles (4-)8-30 cm long, (2.2-)4-20(-26) cm wide, open, lax, ovate, lax, usually long-exserted from the upper sheaths; branches spreading, sometimes ascending, rebranching in the upper third, scaberulous, without spikelets near their base, spikelets usually clustered at the tips, inferior branches 1.5-13 cm long; pedicels (0.5-)1-7(-10) mm long, appressed, scaberulous. Spikelets 2-3(-3.4) mm long, greenish to purplish; glumes subequal to unequal, lanceolate, apices shortly acuminate, 1-veined, scaberulous on the keel, lower glume 1.8-2.8(-3.2) mm long, upper glume 2-3(-3.2) mm long; callus pubescent, with 2 bunches of trichomes; lemmas 1.3-2 mm long, elliptic, apices entire, obtuse, sometimes toothed, 5-nerved, veins prominent distally, unawned, rarely awned from above mid-length, awn up to 2 mm long, inserted 0.8-1.5 mm above the base, straight; paleas absent or up to 0.2 mm long, veinless, glabrous; anthers 3, 0.5-1.4 mm long. Caryopsis 0.8-1.5 mm long, elliptic; endosperm liquid to soft. 2n= 42 ( Harvey 2007).

Anatomy and micromorphology.

Leaf blades flat in transversal section; adaxial furrows medium-sized, wide; adaxial ribs rounded; keel absent; first order bundles circular to slightly elliptical in outline, sheath interrupted adaxially and abaxially, abaxial and adaxial sclerenchyma in girders, narrowing towards the bundle; second order bundles circular in outline, sheath interrupted abaxially, abaxial and adaxial sclerenchyma in strands; intercostal sclerenchyma absent; leaf margins with well-developed sclerenchyma caps, rounded; colorless cells absent (Fig. 31A-C ). Lemmas with transversal thickenings oblong, wider than the unthickened portions of the wall; prickle hairs abundant (Fig. 32A ).

Distribution and habitat.

Agrostis scabra is native from Alaska to Guatemala. It has been introduced in Argentina and Chile ( Rúgolo and Molina 1997), Venezuela, the West Indies and Europe ( Dorr 2014). In the study zone, this species has been collected in the USA states of Arizona, California, New Mexico and Texas; in the Mexican states of Baja California, Baja California Sur, Chiapas, Chihuahua, Coahuila, Durango, Guanajuato, Jalisco, México, Michoacán, Morelos, Nuevo León, Oaxaca, Puebla, Querétaro, San Luis Potosí, Sinaloa, Sonora, Veracruz and Zacatecas; in the Guatemalan state of Huehuetenango (Fig. 26B ). It has also been reported from Mexico City, and the Mexican states of Aguascalientes, Hidalgo, and Tlaxcala ( Dávila et al. 2018; Sánchez-Ken 2019), but no specimens from these states were found. Agrostis scabra grows in open areas of temperate forests, with conifers and Quercus , also in cloud forests, alpine grasslands, stream edges and shrublands, between 630-3500 m a.s.l. (Fig. 27B ).

Phenology.

Specimens with spikelets have been collected year round, but most of them between the months of April and October (Fig. 28B ).

Commentaries.

The plants of this species are variable and at least two forms were observed in the study zone: 1) plants with very conspicuous basal leaves, with filiform and involute blades, distributed in Mexico and Guatemala; 2) plants with well-developed cauline leaves, with broader leaf blades, common in southern USA. Agrostis scabra is often confused with A. perennans , which share several leaf anatomy and lemma micromorphology characters (see the note under the description of that species). Agrostis scabra has been considered a synonym or a variety of A. hyemalis and is often confused with it (see the note under the description of that species).

Conservation status.

Agrostis scabra is a common and widespread species in the study zone. It is represented by 240 collections, with several populations occurring in 25 protected areas. The EOO is 2,076,712 km2 and the AOO is 712 km2. Following the IUCN criteria, the preliminary assessment category is Least Concern (LC).

Representative specimens examined.

Guatemala. Huehuetenango: Municipio Chiantla, Chancol , 15.4999°N, 91.34986°W, 3300 m alt., 28 Aug 2000, M. Véliz et al. 10046 (MEXU [*]) . La Capellanía, 15.42111111°N, 91.44027778°W, 3150 m alt., 20 Jul 2004, M. Véliz 15309 (MEXU [*]) . Mexico. Baja California: Municipio Ensenada, Sierra San Pedro Mártir, moist stream banks, La Víbora, arroyo La Grulla , 4 km SW of La Grulla, [30.86667°N, 115.50833°W], 1900 m alt., 9 Aug 1977, R. Moran 24402 (MEXU [*], SD) . Baja California Sur: Municipio La Paz, arroyo Encinos Blancos, Sierra la Laguna , [23.38333333°N, 109.9833333°W], 1870 m alt., 13 Aug 1987, J.L. León de la Luz 2722 (MEXU) . Chiapas: Municipio Jitotol, 5 km SE of Jitotol, along road to Bochil , [17.03092769°N, 92.8499077°W], 1600 m alt., 24 Feb 1982, D.E. Breedlove 58514 (MEXU, TEX) . Municipio Venustiano Carranza, ejido Laja Tendida, km 17 carretera Venustiano Carranza-Tuxtla Gutierrez , 2 km a Flores Magon , [16.342325°N, 92.669313°W], 630 m alt., 5 Sep 1997, A. Miranda 1275 (MEXU [*]) . Chihuahua: Municipio Ocampo, Parque Nacional de la Cascada de Basaseachic, [28.16666667°N, 108.2083333°W], 1600 m alt., 25 Apr 1987, R. Spellenberg et al. 8428 (MEXU [*,**]); Municipio Temosachic , Nabogame , [28.49543744°N, 108.4808032°W], 1800 m alt., 25 Mar 1988, J.E. Laferrière 1419 (MEXU, TEX) . Coahuila: Municipio Arteaga, El Morro, Sierra de Arteaga , límites con Nuevo León, [25.21307327°N, 100.2847136°W], 2900 m alt., 25 Sep 1991, J.A. Villareal and M.A. Carranza 6300 (CIIDIR, MEXU, XAL) . Durango: Municipio Pueblo Nuevo, ejido El Brillante, lago de Puentecillas , 23.6725°N, 105.4563889°W, 2744 m alt., 28 Oct 2011, S. Heynes et al. 264 (CIIDIR, MEXU [*,**], UAMIZ) . Municipio Santiago Papasquiaro, Bajío de Vacas ( Hacienditas ), [25.040833°N, 105.407778°W], 2659 m alt., 5 Oct 1990, A. Benítez 2633 (CHAPA, CIIDIR, MEXU [*], UAMIZ) . Guanajuato: Municipio Guanajuato, Bufas de Guanajuato , [21.02596283°N, 101.2580131°W], 2140 m alt., 12 May 1981, R. Santillán and A. Mora, 28-R (MEXU) . Jalisco: Municipio Ojuelos, Canon de Bacieros , 14 km SO de Ojuelos, [21.81239946°N, 101.6801703°W], 2350 m alt., 4 Jun 1983, M. Alcocer s.n. (CHAPA, MEXU [*]) . México: Municipio Temascaltepec, 11 km sobre la desviación a Tequesquipan, carretera Toluca-Temascaltepec , [19.06454704°N, 99.94451928°W], 2350 m alt., 15 Feb 1983, E. Manrique 161 (MEXU) . Michoacán: Municipio Pátzcuaro, La Laguna, cerca de San Gregorio, [19.41886944°N, 101.4982472°W], 2700 m alt., 26 Oct 1985, J.S. Martínez 1013 (IEB) . Morelos: Municipio Huitzilac, shore of Laguna Zempoala , 20 km NW of Cuernavaca, [19.04991306°N, 99.31567672°W], 2800 m alt., 8 Dec 1950, N.C. Fassett 28453 (F, US) . Nuevo León: Municipio Galeana, cima del cerro Potosí, [24.87220276°N, 100.232885°W], 3500 m alt., 16 Aug 1989, A. García and S. González 196 (CIIDIR, IBUG, IEB, MEXU, UAMIZ) . Oaxaca: Municipio San Miguel El Grande, 36 km de Tlaxiaco rumbo a Chalcatongo , [17.08138782°N, 97.61677573°W], 2559 m alt., 25 Jun 1980, A.A. Beetle M-4760 (CHAPA, IBUG, MEXU) . Puebla: Municipio Huachinango, near Huachinango , [20.11°N, 98.03°W], 1890 m alt., 12 Apr 1962, A.A. Beetle M-567 (UTC) . Querétaro: Municipio Pinal de Amoles: Puerto de los Velázquez, [21.12092778°N, 99.67360833°W], 2650 m alt., 17 Sep 1993, V. Jaramillo et al. 813 (IEB, MEXU) . San Luis Potosí: Municipio Villa de Arriaga, near the village of San Francisco in the Sierra de San Miguelito ca 25 km SW of San Luis Potosi., [22N, 101.14W], 2200-2400 m alt., 5 Sep 1954, E.R. Sohns 1070 ( US) . Sinaloa: Municipio Concordia, El Palmito , en el parteaguas, 8 km al O del poblado, [23.55579174°N, 105.8468406°W], 2350 m alt., 18 Nov 1984, R. Vega 1385 (MEXU) . Sonora: Municipio Yécora, arroyo El Otro Lado, 3.9 Km E of Yecora on Mex 16, 28.375°N, 108.898333°W, 1560 m alt., 25 May 1998, T.R. Van Devender et al. 98-640 (ASU, MEXU, NY, TEX) . Veracruz: Municipio Las Vigas de Ramírez, Toxtlacoaya , 19.63333333°N, 97.06111111°W, 2320 m alt., 15 Sep 91, H. Sandoval 97 (CHAPA, CIB, MEXU [*]) . Zacatecas: Municipio Jerez, Sierra Los Cardos, 10.5 mi NW of Jerez, W of El Cargadero, on road towards Monte de los Garcia , 22.7099°N, 103.131°W, 2570 m alt., 19 Oct 2007, P.M. Peterson et al. 21406 (CAN, US) . USA. Arizona: Cochise County, Coronado National Forest, ca. 6.6 miles E on Pinery Canyon road from fork to Chiricahua National Monument , [32.00439°N, 109.243154°W], 1676 m alt., 12 Jun 1987, L.R. Landrum and S.S. Landrum 5500 (ASC, ASU) . Pima County, Rose Canyon Lake , E end, ca. 3 km S of Mount Bigelow, [32.3833°N, 110.708°W], 2113, 17 Sep 1992, M.A. Baker 10209 (ASU [*]) . California: San Diego County, SW of Combs Peak, canyon off of Chihuahua-Lost Valley Road just NW of Sky Oaks Field Station, on Bureau of Land Management lands, 33.38207°N, 116.62718°W, 1405 m alt., 15 Aug 2010, J.P. Rebman 20319 (SD [*]) . New Mexico: Hidalgo County, Peloncillo Mountains, Cloverdale Creek , just inside National Forest boundary, 31.40937429°N, 108.9147098°W, 1585 m alt., 1 May 1991, K.W. Allred 5232 (IBUG) . Texas: Jeff Davis County, Madera Canyon , roadside park in canyon along highway 118, 30.7°N, 104.1°W, 1768 m alt., 29 Jun 1979, R.D. Worthington 4691 (COLO, UTEP). See Suppl. materials 2, 3 for additional examined specimens .

Figures

Figure 4. Florets of Agrostis species observed with SEM A A. bourgaei B A. calderoniae C A. capillaris D A. elliottiana E A. exarata F A. ghiesbreghtii G A. gigantea H A. hyemalis I A. laxissima J A. microphylla K A. pallens L A. perennans M A. scabra N A. stolonifera O A. subpatens P A. subrepens Q A. tolucensis R A. turrialbae S A. variabilis. Scale bars: 0.3 mm.

Figure 26. Map of known geographic distribution of Agrostis species, based on herbarium specimen data A A. perennans B A. scabra C A. stolonifera D A. subpatens E A. subrepens F A. tolucensis.

Figure 27. Elevation histograms of Agrostis species A A. perennans B A. scabra C A. stolonifera D A. subpatens E A. subrepens F A. tolucensis G A. turrialbae H A. variabilis.

Figure 28. Phenology histograms of Agrostis species A A. perennans B A. scabra C A. stolonifera D A. subpatens E A. subrepens F A. tolucensis G A. turrialbae H A. variabilis.

Figure 29. Agrostis scabra A whole plant B ligular area C detail of a terminal branche of the panicle D spikelet, E floret, abaxial view, F floret, adaxial view. Based on Aceval 775 (MEXU). Scale bars: 3 cm (A); 5 mm (B, C); 0.5 mm (D); 0.3 mm (E, F).

Figure 30. Calluses of Agrostis species observed with SEM A A. scabra B A. stolonifera C A. subpatens D A. subrepens E A. tolucensis F A. turrialbae G A. variabilis. Scale bars: 50 μm.

Figure 31. Leaf blade anatomy in transversal section of Agrostis species, in general view, and details of lateral bundles. A - C A. scabra D - E A. stolonifera F - G A. subpatens H - I A. subrepens. Scale bars: 0.1 mm.

Figure 32. Lemma surface of Agrostis observed with SEM A A. scabra B A. stolonifera C A. subpatens D A. subrepens E A. tolucensis F A. turrialbae G A. variabilis. Scale bars: 15 μm.