Bromus richardsonii Link. Atypical 1833

19. Bromusrichardsonii Link (1833: 281). Figs. 61, 62. Zerna richardsonii (Link) Nevski (1934: 17). Bromus ciliatus var. richardsonii (Link) Boivin (1967: 521). Zerna canadensis subsp. richardsonii (Link) Tzvelev (1971: 54). Bromopsis richardsonii (Link) Holub (1973: 168). Bromopsis canadensis subsp...

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Main Authors: Saarela, Jeffery M., Peterson, Paul M., Valdés-Reyna, Jesus
Format: Text
Language:unknown
Published: Zenodo 2014
Subjects:
Eme
Online Access:https://dx.doi.org/10.5281/zenodo.5156705
https://zenodo.org/record/5156705
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Summary:19. Bromusrichardsonii Link (1833: 281). Figs. 61, 62. Zerna richardsonii (Link) Nevski (1934: 17). Bromus ciliatus var. richardsonii (Link) Boivin (1967: 521). Zerna canadensis subsp. richardsonii (Link) Tzvelev (1971: 54). Bromopsis richardsonii (Link) Holub (1973: 168). Bromopsis canadensis subsp. richardsonii (Link) Tzvelev (1976: 214). Type:— Hab. in America septentrionali occidentali. Semina misit cl. Dr. Richardson [Grown in Berlin from seed provided by Dr. Richardson] (holotype B, destroyed fide Wagnon 1952). Bromus purgans var. longispicatus Hooker (1840: 252). Type:— CANADA. Rocky Mountains, T. Drummond s.n. (isotype US- A865460! fragm.). Bromus mucroglumis Wagnon (1952: 67). Bromopsis mucroglumis (Wagnon) Holub (1973: 168). Type:— UNITED STATES OF AMERICA. Cultivated: grown in the greenhouse of the Botanical Garden, University of Michigan, from seed reproduced by the Soil Conservation Service (A-5712), Albuquerque, New México, and originally collected by Goodding, Locke, & Johnson at South Cave Creek, Chiricahua Mts., Cochise Co., Arizona, 28 July 1948, H.K. Wagnon 1520 (holotype MICH-1108614!, isotype US-2154824!). Bromus thysanoglottis Soderstrom & Beaman (1968: 509). Type:— MÉXICO. Durango: pine-oak region, Sierra Madre Occidental, Wof Ciudad Durango, 2 mi SW of Buenos Aires, 8800 ft, on precipitous slope, 8 September 1960, in clay soil, J.R. Reeder, C.G. Reeder & T.R. Soderstrom 3348 (holotype US-2457688!, isotypes ARIZ-246155!, ARIZ-226130!, YU- 000863!). Plants perennial, not rhizomatous. Culms up to 120 cm tall, 1.5–6 mm wide at base, erect or ascending, sometimes decumbent at the base, glabrous below inflorescences; nodes 2–6, glabrous or pubescent. Leaf sheaths glabrous or pubescent to pilose, hairs sometimes restricted to distal sheath margins, hairs up to 1.5 mm long; auricles absent; ligules 0.6–3.3 mm long, glabrous or minutely pubescent, erose-lacerate; blades up to 38 cm × (3–)4–10.5(–13) mm, flat, glabrous or pubescent to pilose, hairs up to 1.5 mm long, margins smooth or serrulate. Panicles 12–35 cm × 2–17.5 cm, open, nodding, branches ascending to spreading or drooping, shorter or longer than spikelets, glabrous, scabrous or pubescent, 1–5 spikelets per branch. Spikelets 1.7–3.2(–3.6) cm long, 3–9(–12)-flowered, elliptic to lanceolate, terete to moderately laterally compressed, rachillas sometimes visible at maturity; glumes glabrous or minutely to strongly pubescent, hairs sometimes restricted to margins, hairs up to 1 mm long, margins hyaline, midnerves glabrous, scabrous or pubescent; lower glumes 5.5–9.5(–12) mm long, narrowly lanceolate to ovate–lanceolate, 1(–3)-nerved, green to purplish-green along and between the nerves; upper glumes (7–)8–12.5(–14.5) mm long, 3-nerved, obovate-lanceolate, green to purplish-green along and between the nerves, apices acute to mucronate, mucros 0.3–1.5(–2) mm long; lemmas (9–)10–13.5(–15) mm × 2–2.8 mm, elliptic to lanceolate, rounded over the backs, apices entire or minutely bifid, the cleft to 0.2 mm long, 7-nerved, green to purplish-green along and between the nerves, margins pubescent, hairs up to 1 mm long, backs glabrous or weakly to densely pubescent proximally and glabrous to scabridulous distally, hairs up to 0.7 mm long; awns 3.1–6.5 mm long, arising 0–0.5 mm below lemma apex, straight; paleas shorter and narrower than lemmas, backs glabrous or puberulent to pubescent, keels glabrous or ciliate, cilia up to 0.4 mm long; anthers 1–2.6(–3.4) mm long; caryopses 7−10 mm long. 2n = 28 (Mitchell & Wilton 1965, Armstrong 1983, Ward & Spellenberg 1988, Peterson et al. 2001). Distribution: ―Native. In México B. richardsonii is known from Baja California, Baja California Sur, Chihuahua, Durango, Coahuila, Michoácan, Nuevo León, Querétaro and Tlaxcala (Fig. 63). In North America, B. richardsonii is generally distributed west of the continental divide from the Yukon territory to central México, with disjunct populations known from the Cypress Hills in southern Alberta and Saskatchewan, the Black Hills in South Dakota and western Texas (Peterson et al. 2001, Pavlick & Anderton 2007). Ecology:— Steep to gentle slopes on rock outcrops or wooded habitats in granitic or calcareous soils, often in roadcuts, cliffs and arroyos; associated with Pinus durangensis , P. cooperi Blanco (1949: 185), P. jeffreyi , P. quadrifolia Parl. ex Sudworth (1897: 17), P. teocote , P. ayacahuite , Quercus arizonica Sargent (1895: 92), Q. durifolia Seemen in Loesener (1900: 95), Q. emoryi , Q. rugosa , Q. sideroxyla , A. concolor Lindl. ex Hildebrand (1861: 261), Pseudotsuga menziesii , Picea engelmannii , Cupressus arizonica , Juniperus deppeana , Arbutus arizonica , A. tessellata Sørensen (1987: 263), A. xalapensis , Holodiscus dumosus (S. Watson in Brewer 1876: 170) Heller (1898: 4), Arctostaphylos pungens , A. patula Greene (1891: 171), A. pringlei Parry (1887: 494), Populus tremuloides Michaux (1803b: 243), Platanus wrightii , Symphoricarpos oreophilus Gray (1873: 14), Alnus , Prunus serotina , Pachistima myrsinites , Garrya macrophylla , Cornus stolonifera , Ribes , Salvia , Heuchera Linnaeus (1753: 226), Lupinus , Senecio , Ceanothus , Baccharis , Brickellia Elliott (1824 [1823]: 290), Cercocarpus , Stevia Cavanilles (1797: 32), Geranium , Thalictrum , Pedicularis Linnaeus (1753: 607), Rubus , Sedum Linnaeus (1753: ATAXONOMIC REVISION OF BROMUS (POACEAE) Phytotaxa 185 (1) © 2014 Magnolia Press 113 430), Yucca Linnaeus (1753: 319), Physocarpus , Silene Linnaeus (1753: 416) and Cerastium Linnaeus (1753: 437). Elevation: 1500−3250 m. Espejo-Serna (2000) noted B. richardsonii (as B. ciliatus ) to be introduced in México, which is incorrect. Common Name: ―Richardson’s brome (English). Comments: ―Plants treated here as B. richardsonii were recognized (in part, see discussion of B. mucroglumis below) as B. ciliatus in several Mexican treatments (Soderstrom & Beaman 1968, Beetle 1977, 1987, Gould & Moran 1981), while a more recent treatment recognized them as B. richardsonii (Herrera Arrieta 2001). The distinctions between B. ciliatus and B. richardsonii were, for a long time, unclear. Bromus richardsonii has been variously recognized as a distinct species (Shear 1900, Hitchcock 1913, Wagnon 1952, Kearney & Peebles 1960, Mitchell & Wilton 1965, Mitchell 1967, Hultén 1968, Welsh 1974, Pavlick 1995, Peterson et al. 2001, Saarela et al. 2005, Pavlick & Anderton 2007, Saarela 2008, Saarela & Peterson 2012) or as a synonym of B. ciliatus (Hitchcock 1951, Soderstrom & Beaman 1968, Allred 1993, Kartesz & Allen 1999, Espejo-Serna et al. 2000, Douglas et al. 2001, Hatch & Haile 2012). In a detailed study of the complex, Peterson et al. (2001) identified distinctive morphological, cytological and genetic differences that support recognition of these taxa as distinct species (also see Saarela 2008, Saarela & Peterson 2012). Bromus ciliatus is distributed across southern Canada and the United States, except south-central and southeastern U.S.A. (Pavlick & Anderton 2007); it is not known from México. Two collections from Municipio de Yécora, Sonora ( Reina 98-1389A & Van Devender Van Devender 98- 1590 , Reina & Trauba ) are unusual in having 3-nerved lower glumes and long awns (to 6.5 mm). Aspecimen from Volcán Tequila in Jalisco ( Webster 15862 , MICH) was treated as B. anomalus by McVaugh (1983), who noted this and another collection ( Puga 6347 , not seen) to be "robust, up to 1.2 m tall, with woolly sheaths and spikelets 2–4 cm long, suggesting in these characters B. lanatipes (Shear) Rydb., which has by some authors been treated as a variety of B. anomalus " (McVaugh 1983: 101). We treat this collection as B. richardsonii , along with others from Cerro Volcán ( Peterson & Rosales 16061 , 16067 ). 114 Phytotaxa 185 (1) © 2014 Magnolia Press SAARELA ET AL. ATAXONOMIC REVISION OF BROMUS (POACEAE) Phytotaxa 185 (1) © 2014 Magnolia Press 115 Taxonomic Status of Bromus mucroglumis — Bromus mucroglumis was described from the Chiricahua Mts. in Arizona by Wagnon (1950), but has not generally been recognized until relatively recently, when it was resurrected by Beetle (1987) and Pavlick (1995) (Peterson et al. 2001). Bromus mucroglumis has since been reported from Colorado, southwestern New México, Arizona (San Francisco Mountains), Chihuahua, Sonora, Durango, Coahuila, Nuevo León and Baja California Sur (Beetle 1987, Pavlick 1995, Herrera Arrieta 2001, Peterson et al. 2001, Clayton et al. 2002 onwards, Pavlick & Anderton 2007, Shaw 2008). Bromus mucroglumis was included in B. richardsonii by Kearney & Peebles (1960), whereas Allred (1993) treated it as as a synonym of B. lanatipes in New México. Soderstrom & Beaman (1968) noted difficulties with the circumscription of B. mucroglumis . They found that several paratypes of B. mucroglumis represent multiple species, indicative of some confusion in the limits of the species when it was described by Wagnon (1950). We agree with Soderstrom & Beaman (1968), as did Gould & Moran (1981), that the paratype collections Carter et al. 2341 and Brandegee 73 are B. anomalus , and we recognize the paratype collection Pennell 1929 (GH!, US, not seen), which was treated as B. porteri by Soderstrom & Beaman (1968), as B. frondosus . We have not seen Le Sueur 092 (MO, US), which Soderstrom & Beaman (1968) recognized as B. thysanoglottis (see below for discussion of this taxon). Peterson et al. (2001) included four individuals of B. mucroglumis (three from Arizona, one from Chihuahua) in their taxonomic study of B. ciliatus and B. richardsonii . In a discriminant analysis, B. mucroglumis was wellseparated from the other taxa, the most important characters and states for its separation being lower glume length, lemma pubescence (hairs not restricted to margins) and adaxially hairy top culm blades. The four individuals of B. mucroglumis fell among the lower range of variation of B. richardsonii or were more or less intermediate between clusters of B. ciliatus and B. richardsonii in multiple bivariate comparisons of morphological and ecological (i.e., elevation) characters. The bivariate plots did not consider glume and lemma pubescence. Based on AFLP data, Peterson et al. (2001) found individuals of B. mucroglumis (all collected from a single population) to fall within a larger cluster comprising individuals of B. richardsonii . Based on their small sample of B. mucroglumis , Peterson et al. (2001) did not make a conclusion on the taxonomic status of B. mucroglumis . In México it is generally straightforward to identify a plant as a member of the B. richardsonii – B. mucroglumis complex; however, throughout México in the field and in the herbarium we have experienced considerable difficulties understanding the differences between these species, as there is considerable variation in the vestiture of their glumes, lemmas, leaf sheaths and leaf blades of plants. Wagnon (1950) described B. mucroglumis as differing from B. richardsonii by its pubescent nodes, blades pilose above, glumes pubescent to pilose, rarely glabrous, second glumes mucronate and paleas puberulent to pilose. He observed that many plants are intermediate between B. mucroglumis and B. richardsonii , with the variation in the direction of B. richardsonii , and noted that these plants could arbitrarily be placed in either taxon. He suggested there may be introgression with B. richardsonii , and possibly with B. lanatipes . We have seen two of the supposedly intermediate collections cited from Baja California: Wiggins & Demaree 4873 (RSA-POM) and Wiggins & Demaree 4960 (NY, RSA-POM), which have glabrous glumes and lemmas that are pubescent along the margins and weakly to moderately puberulent or pubescent on the backs proximally and glabrous distally, glabrous blades and sheaths pubescent to pilose with stiff hairs. Wagnon (1950) did not indicate in his paper how the specimens varied, but he annotated the two RSA-POM sheets as " Bromus richardsonii Link. Atypical form with pubescent nodes; approaching B. mucroglumis ". Although most specimens from Baja California (Sierra San Mártir) have glabrous nodes, several have weakly pubescent ( Moran 15626 , SD; Witham 407 , SD; Thorne et al. 57251 , RSA-POM) or pubescent nodes ( Rebman & Vinton 5558 , SD, RSA-POM; Moran & Thorne 14127 , SD; Thorne et al. 61430 , RSA-POM; Noyes et al. 699 , RSA-POM). Pubescent nodes are known in B. richardsonii elsewhere in its range (Peterson et al. 2001, Saarela 2008). There is considerable variation in the pubescence of the lemmas and glumes in the complex: some plants have lemmas that are pubescent throughout, while others are pubescent along the margins and on the lower backs and glabrous to scabridulous proximally. Similarly, some plants have pubescent glumes, while others have glabrous glumes. These differences in lemma pubescence have been emphasized previously in distinguishing B. mucroglumis from B. richardsonii (e.g., Beetle 1987 (as B. ciliatus ), Herrera Arrieta 2001). However, this range of variation is recognized in B. richardsonii in North America north of México in some recent treatments (e.g., British Columbia: Saarela 2008; California: Saarela & Peterson 2012). Examples of specimens from British Columbia with lemmas pubescent throughout include Malte s.n. (CAN-93967) and Saarela et al. 728 (CAN-590409), and the latter specimen also has pubescent glumes. 116 Phytotaxa 185 (1) © 2014 Magnolia Press SAARELA ET AL. Like Wagnon (1950), previous authors have described B. mucroglumis as having blades that are pilose on at least one surface (Beetle 1987, Pavlick 1995, Pavlick & Anderton 2007). Based on our examination of herbarium specimens we find that leaf blade pubescence varies independently with lemma and glume pubescence. Some plants with pubescent lemmas have pilose blades (e.g., Peterson et al. 15418 , 15441 , 15443 , 16923 , 20135 Peterson & Brothers 16999 , 17029 Peterson & Annable 12443 Peterson & Cayouette 15354 Peterson & González-Elizondo 16012 , 16029 ) and others have glabrous blades (e.g., Peterson et al. 15416 , 16940 , 17869 , 10052 , 20064 Peterson & Sánchez Alvarado 20008 Peterson & Cayouette 15408 ). Conversely, many plants from México with lemmas pubescent only along the margins have glabrous blades, but there are also several with pubescent blades (e.g., Chihuahua: Peterson & Cayouette 15363 , Peterson et al 20069 Durango: Peterson & Cayouette 15387 , Peterson & González-Elizondo 16027 , Peterson et al. 21197 ). Although plants with pubescent blades are not known in B. richardsonii in North America north of México (Peterson et al. 2001, Pavlick & Anderton 2007, Saarela 2008, Saarela & Peterson 2012), we attribute the pubescence in Mexican plants to local variation in this wide-ranging species. Similarly, we find the mucronate glume characters Wagnon used to distinguish B. mucroglumis from B. richardsonii to also vary independently with lemma and glume pubescence, and with leaf blade pubescence. Mucronate second glumes are present in many individuals of the complex in México, as well as in plants as far north as British Columbia (Saarela et al. 2008). Given the broad range of variation in the B. mucroglumis – B. richardsonii complex, it is not possible to circumscribe taxa with a suite of co-varying morphological characters. Consequently, we recognize all plants as a single taxon, B. richardsonii . Plants in the southwestern United States recognized as B. mucroglumis should be studied closely to characterize their variation in relation to sympatric B. richardsonii . Taxonomic status of Bromus thysanoglottis — Bromus thysanoglottis was described from the Sierra Madre Occidental in Durango by Soderstrom & Beaman (1968); they also cited specimens from Chihuahua. They diagnosed this taxon based on the presence of long hairs on the adaxial surface of the blade behind the ligule, and stated this character does not occur in other Bromus species in México and Central America. They considered B. thysanoglottis to be most closely related to B. anomalus . Most subsequent authors have recognized the taxon (Espejo-Serna et al. 2000, Herrera Arrieta 2001, Clayton et al. 2002 onwards, Herrera Arrieta & Cortés Ortiz 2009, Espejo Serna 2012), but without critical examination. By contrast, Beetle (1977) treated it as a synonym of B. mucroglumis (here included in B. richardsonii ), a circumscription with which we agree. Plants recognized as B. thysanoglottis by previous authors fall within the range of variation recognized here in B. richardsonii . Specimens Examined:— MÉXICO. Baja California: Arroyo de la quinta, Ejido “El Largo”, 2100 m, 13 October 1990, A . Benítez P. 2837 (ANSM); along observatory road 1/ 4 mi below gate, [31.0372°N, 115.4542°W], ca. 2650 m, 18 September 1983, R. F . Thorne, K. Kubitzki, P. Peterson & C. Annable 57251 (RSA-POM-345660); below road Nof Corral de Sam, 31.0667°N, 115.5667°W, 2000 m, 30 July 1970, R . Moran 18051 (RSA-POM- 231175, SD-76461); Sierra San Pedro Mártir, Cerro "2828", [31.0372°N, 115.4542°W], 2800 m, 9 August 1969, H. V . Witham 407 (SD-71764, RSA-POM-364159); Sierra San Pedro Mártir, La Sanca creek, ca. 5 mi NW of La Grulla, [30.99°N, 115.4°W], 6700 ft [2042 m], 17 September 1930, I. L . Wiggins & D. Demaree 4873 (NY, RSA- POM-218732); NW end of the : Published as part of Saarela, Jeffery M., Peterson, Paul M. & Valdés-Reyna, Jesus, 2014, A taxonomic revision of Bromus (Poaceae: Pooideae: Bromeae) in México and Central America, pp. 1-147 in Phytotaxa 185 (1) on pages 113-122, DOI: 10.11646/phytotaxa.185.1.1 : {"references": ["Link, J. H. F. (1833) Hortus Regius Botanicus Berolinensis descriptus 2. apud G. Reimer, Berolini, 376 pp. http: // dx. doi. org / 10.5962 / bhl. title. 13688", "Nevski, S. A. (1934) Schedae ad Herbarium Florae Asiae Mediae ab Universitate Asiae Mediae editum. Trudy Sredne- Aziatskogo Gosudarstvennogo Universiteta. Seriya 8 b, Botanika 17: 1 - 94.", "Boivin, B. (1967) Enumeration des plantes du Canada. VI - Monopsides, (2 eme partie). Naturaliste canadien, 94: 471 - 528. Bongard, M. (1832) Observations sur la vegetation de L'Ile de Sitcha. Memoires de l'Academie Imperiale des Sciences de St. - Petersbourg. Sixieme Serie. Sciences Mathematiques, Physiques et Naturelles 2: 119 - 177. http: // dx. doi. org / 10.5962 / bhl. title. 62405", "Tzvelev, N. N. (1971) Za\u043citki o \u043dikoto\u0440\u044bk \u0440odak z\u043bakov \u0444\u043bo\u0440\u044b \u0421\u0421\u0421\u0420. Novosti Sisstematiki Vysshikh Rastenii 7: 42 - 59.", "Holub, J. (1973) New names in Phanerogamae 2. Folia Geobotanica & Phytotaxonomica 8: 155 - 179. http: // dx. doi. org / 10.1007 / bf 02854562", "Tzvelev, N. N. (1976) Zlaki SSSR. Nauka, Leningrad, 788 pp.", "Wagnon, H. K. (1952) A revision of the genus Bromus, section Bromopsis of North America. Brittonia 7: 415 - 480. http: // dx. doi. org / 10.2307 / 2804968", "Hooker, W. J. (1840) Flora boreali-americana, or, the botany of the northern parts of British America: compiled principally", "Soderstrom, T. R. & Beaman, J. H. (1968) The genus Bromus (Gramineae) in Mexico and Central America. Publications of the Museum, Michigan State University, Biological Series 3: 465 - 520.", "Mitchell, W. W. & Wilton, A. C. (1965) Redefinition of Bromus ciliatus and B. richardsonii in Alaska. Brittonia 17: 278 - 284. http: // dx. doi. org / 10.2307 / 2805298", "Armstrong, K. C. (1983) The relationships between some Eurasian and American species of Bromus section Pnigma as determined by the karyotypes of some F 1 hybrids. Canadian Journal of Botany 61: 700 - 707. http: // dx. doi. org / 10.1139 / b 83 - 080", "Ward, D. E. & Spellenberg, R. (1988) Chromosome counts of angiosperms from New Mexico and adjacent areas. Phytologia 64: 390 - 398.", "Peterson, P. M., Cayouette, J., Ferdinandez, Y. S. N., Coulman, B. & Chapman, R. E. (2001) Recognition of B. richardsonii and B. ciliatus: Evidence from morphology, cytology, and DNA fingerprinting (Poaceae: Bromeae). Aliso 20: 21 - 36.", "Pavlick, L. E. & Anderton, L. K. (2007) Bromus L. In: Barkworth, M. E., Capels, K. M., Long, S., Anderton, L. K. & Piep, M. B. (Eds.) Flora of North America, Volume 24. Magnoliophyta: Commelinidae (in part): Poaceae, part 1. Oxford University Press, Oxford and New York, pp. 193 - 237.", "Blanco, C. E. (1949) Pinus cooperi C. E. Blanco, sp. nova. Anales del instituto de Biologia de la Universidad Nacional de Mexico 20: 183 - 187.", "Sudworth, G. B. (1897) Nomenclature of arborescent flora of United States. Division of Forestry: Bulletin [U. S. Department of Agriculture] 14: 1 - 419.", "Sargent, C. S. (1895) Notes on North American oaks. Garden and Forest 8: 92.", "Loesener, T. (1900) Beitrage zur Kenntnis der Flora von Central-Amerika (einschliesslich Mexico). Botanische Jahrbucher fur Systematik, Pflanzengeschichte und Pflanzengeographie 29: 86 - 106.", "Hildebrand, F. H. G. (1861) Die Verbreitung der Coniferen in der Jetztzeit und in den fruheren geologischen Perioden. Verhandlungen des Naturhistorischen Vereines der Preussischen Rheinlande und Westphalens 18: 199 - 384.", "Sorensen, P. D. (1987) Arbutus tessellata (Ericaceae), new from Mexico. Brittonia 39: 263 - 267. http: // dx. doi. org / 10.2307 / 2807390", "Brewer, H. J., Watson, S. & Gray, A. (1876) Geological Survey of California. J. D. Whitney, State Geologist. Botany 1. Welch, Bigelow, & Co., Cambridge, 628 pp.", "Heller, A. A. (1898) Catalogue of North American plants north of Mexico, exclusive of the lower cryptogams. Lancaster Pa., 160 pp. http: // dx. doi. org / 10.5962 / bhl. title. 57297", "Greene, E. L. (1891) New or noteworthy species. Pittonia 2: 161 - 173.", "Parry, C. C. (1887) California manzanitas. Bulletin of the California Academy of Sciences 2: 483 - 496.", "Michaux, A. (1803 b) Flora boreali-americana: sistens caracteres plantarum quas in America septentrionali collegit et detexit Andreas Michaux, ... tabulis aenis 51 ornata 2. apud Fratres Levrault, Parisiis et Argentorati [Paris et Strasbourg], 340 pp. http: // dx. doi. org / 10.5962 / bhl. title. 330", "Gray, A. (1873) Revision of the genus Symphoricarpus. Journal of the Linnean Society of London, Botany 14: 9 - 12. http: // dx. doi. org / 10.1111 / j. 1095 - 8339.1873. tb 00298. x", "Linnaeus, C. (1753) Species plantarum: exhibentes plantas rite cognitas, ad genera relatas, cum differentiis specificis, nominibus trivialibus, synonymis selectis, locis natalibus, secundum systema sexuale digestas, 2 vols. Impensis Laurentii Salvii, Holmiae [Stockholm], 1200 pp. http: // dx. doi. org / 10.5962 / bhl. title. 669", "Elliott, S. (1824 [1823]) Sketch of the botany of South Carolina and Georgia 2 (3). J. R. Schenck, Charleston, pp. 209 - 312. http: // dx. doi. org / 10.5962 / bhl. title. 9508", "Cavanilles, A. J. (1797) Icones et descriptiones plantarum, quae aut sponte in Hispania crescunt, aut in hortis hospitantur 4 (1). Typographia regia, Madrid, pp. 1 - 36, pl. 301 - 360.", "Espejo-Serna, A., Lopez-Ferrari, A. R. & Valdes-Reyna, J. (2000) Poaceae. In: Espejo-Serna, A. & Lopez-Ferrari, A. R. (Eds.) Las Monocotiledoneas Mexicanas: Una Sinopsis Floristica. 1. Lista de referencia. Partes IX a XI 10. Consejo Nacional de la Flora de Mexico, A. C., Universidad Autonoma Metropolitana-Izapalapa, y Comision Nacional para el conocimiento y uso de la Biodiversidad, Mexico, D. F., pp. 7 - 236.", "Beetle, A. A. (1977) Noteworthy grasses from Mexico V. Phytologia 37: 317 - 407.", "Beetle, A. A. (1987) Las Gramineas de Mexico, Tomo II. Secretaria de Agricultura y Recursos Hidraulicos: COTECOCA, Mexico, 344 pp.", "Gould, F. W. & Moran, R. (1981) The grasses of Baja California, Mexico. Memoirs of the San Diego Society of Natural History 12: 1 - 140.", "Herrera Arrieta, Y. (2001) Las Gramineas de Durango. Instituto Politecnico Nacional y Conabio, Durango, 478 pp.", "Shear, C. L. (1900) A revision of the North American species of Bromus occurring north of Mexico. United States Department of Agriculture, Division of Agrostology, Bulletin 23: 5 - 66.", "Hitchcock, A. S. (1913) Mexican grasses in the United States National Herbarium. Contributions from the United States National Herbarium 17: 181 - 389.", "Kearney, T. H. & Peebles, R. H. (1960) Arizona Flora. University of California Press, Berkeley, 1085 pp.", "Mitchell, W. W. (1967) Taxonomic synopsis of Bromus section Bromopsis (Gramineae) in Alaska. Canadian Journal of Botany 45: 1309 - 1313. http: // dx. doi. org / 10.1139 / b 67 - 138", "Hulten, E. (1968) Flora of Alaska and neighbouring territories: a manual of the vascular plants. Stanford University Press, Stanford, California, 1032 pp.", "Welsh, S. L. (1974) Anderson's Flora of Alaska and adjacent parts of Canada. Brigham Young University Press, Provo, 724 pp.", "Pavlick, L. E. (1995) Bromus L. of North America. Royal British Columbia Museum, Victoria, 160 pp.", "Saarela, J. M., Peterson, P. M. & Cayouette, J. (2005) Bromus hallii (Poaceae), a new combination for California, U. S. A., and taxonomic notes on Bromus orcuttianus and Bromus grandis. Sida 21: 1997 - 2013.", "Saarela, J. M. (2008) Taxonomy of Bromus (Poaceae: Pooideae: Bromeae) sections Bromopsis, Bromus, and Genea in British Columbia, Canada. Journal of the Botanical Research Institute of Texas 2: 323 - 372.", "Saarela, J. M. & Peterson, P. M. (2012) Bromus. In: Baldwin, B. G., Boyd, S., Ertter, B. J., Patterson, R. W., Rosatti, T. J. & Wilken, D. H. (Eds.) The Second Edition of the Jepson Manual. University of California Press, Berkeley, Los Angeles and London, pp. 1426 - 1431, 1435.", "Hitchcock, A. S. (1951) Manual of grasses of the United States (ed. 2, revised by A. Chase). United States Department of Agriculture Miscellaneous Publication no. 200. United States Government Printing Office, Washington, D. C., 1051 pp. http: // dx. doi. org / 10.5962 / bhl. title. 65332", "Allred, K. W. (1993) Bromus, section Pnigma, in New Mexico, with a key to the bromegrasses of the state. Phytologia 74: 319 - 345.", "Kartesz, J. T. M. & Allen, C. (1999) Synthesis of the North American Flora, Version 1.0 [CD-ROM]. Chapel Hill, NC.", "Douglas, G. W., Meidinger, D. & Pojar, J. (2001) Illustrated Flora of British Columbia 7. Monocotyledons (Orchidaceae through Zosteraceae). Victoria, British Columbia Ministry of Sustainable Resource Management and Ministry of Forests, 379 pp.", "Hatch, S. L. & Haile, K. C. (2012) Checklist of Texas grass species and a key to the genera. Phytoneuron 2012 - 57: 1 - 60.", "McVaugh, R. (1983) Flora Nova-Galiciana. A descriptive account of the vascular plants of western Mexico. The University of Michigan, Ann Arbor, 436 pp.", "Wagnon, H. K. (1950) Three new species and one new form in Bromus. Leaflets of Western Botany 6: 64 - 69.", "Clayton, W. D., Vorontsova, M. S., Harman, K. T. & Williamson, H. (2002 onwards) World grass species: synonymy. Available from: http: // www. kew. org / data / grasses-syn. html.", "Shaw, R. B. (2008) Grasses of Colorado. University Press of Colorado, Boulder, 650 pp.", "Herrera Arrieta, Y. & Cortes Ortiz, A. (2009) Diversidad de las gramineas de Durango, Mexico. Polibotanica 28: 49 - 68.", "Espejo Serna, A. (2012) El endemismo en las Liliopsida Mexicanas. Acta Botanica Mexicana 100: 195 - 257."]}