Muhlenbergia peruviana (P. Beauv.) Steud., Nomencl. Bot. (ed. 2) 1:41. 1840.

Peterson, Paul M., Vega, Isidoro Sanchez, Romaschenko, Konstantin, Giraldo-Canas, Diego & Rodriguez, Nancy F. Refulio, 2018, Revision of Muhlenbergia (Poaceae, Chloridoideae, Cynodonteae, Muhlenbergiinae) in Peru: classification, phylogeny, and a new species, M. romaschenkoi, PhytoKeys 114, pp. 123-206 : 165-166

15. Muhlenbergia peruviana (P. Beauv.) Steud., Nomencl. Bot. (ed. 2) 1:41. 1840. Fig. 11A-D

Clomena peruviana P. Beauv., Ess. Agrostogr. 28, t. 7, f. 10; t. 3, f. 20. 1812. Agrostis peruviana (P. Beauv.) Spreng., Syst. Veg. 1:262. 1825. Type: Peru, M. Thibaut s.n. (holotype: P!; isotype: E-00373717 [image!]).

Clomena peruviana var. pulvinata Nees, Gramineae 12-13. 1841. Muhlenbergia peruviana var. pulvinata (Nees) Nees & E. Mey. ex Kuntze, Revis. Gen. Pl. 3(3):357. 1898. Type: Peru, Lago Titicaca, Apr, J.F.J. Meyen s.n. (holotype: B; isotype: US-3376134 fragm. ex B!).

Muhlenbergia nana Benth., Pl. Hartw. 262. 1846. Type: Ecuador, Mt. Cotopaxi, 1843, Hartweg 1458 (holotype: K!; isotypes: BAA-1629!, K!, LE!, P!, US-91916 fragm. ex P!, US-995896 fragm. ex P-STEUD & fragm. ex BR!).

Muhlenbergia pusilla Steud., Syn. Pl. Glumac. 1:177. 1854. Type: Mexico, México, Valley of Toluca, Oct. 1827, J. L. Berlandier 1141 (holotype: P!; isotypes: BAA-1635!, K!, MO-2974185!, P!, US-1084517!, US-2561239!, US-91910 fragm. ex P!).

Epicampes bourgeaei E. Fourn., Mexic. Pl. 2: 88. 1886. Type: Mexico, Veracruz, Escamala, Refrou D’Orizaba, 26 Aug 1866, E. Bourgeau 2973 (holotype: P!; isotype: US-A0865984 fragm ex P!).

Muhlenbergia bourgeaei E. Fourn., Mexic. Pl. 2:86. 1886. Epicampes bourgeaei (E. Fourn.) M.E. Jones, Contr. W. Bot. 14:7. 1912, nom. illeg. hom. Type: Mexico, Valle de Mexico, Desierto Viejo, 3 Nov 1865, M. Bourgeau 1309 (lectotype: P! designated by Peterson and Annable, Syst. Bot. Monogr. 31:73. 1991; isotype: US-87243 fragm. ex P!).

Muhlenbergia pulcherrima Scribn. ex Beal, Grass. N. Amer. 2:240. 1896. Type: Mexico, Chihuahua: Sierra Madres, dry ledges of porphyry, 30 Sep 1887, C.G. Pringle 1416 (holotype: MSC!; isotypes MO-3727978!, NY!, US-995494!, VT!).

Muhlenbergia peruviana var. elatior Kuntze, Revis. Gen. Pl. 3(2): 357. 1898. Type: Bolivia, Tunarigebirge, 3000 m, May 1892, Kuntze s.n. (lectotype: NY! designated by Peterson and Annable, Syst. Bot. Monogr. 31:73. 1991: isotype: fragm. & photo US!).

Muhlenbergia peruviana var. subcaespitosa Kuntze, Revis. Gen. Pl. 3(3):357. 1898. Type: Bolivia, Tunari Mts., 4600 m, 4 May 1892, Kuntze s.n. (lectotype: NY! designated by Peterson and Annable, Syst. Bot. Monogr. 31:73. 1991).

Muhlenbergia peruviana fo. versicolor Kuntze, Revis. Gen. Pl. 3(3):357. 1898. Type: Bolivia, Tunarigebirge, 3000 m, May 1892, Kuntze s.n. (lectotype: NY! designated by Peterson and Annable, Syst. Bot. Monogr. 31:73. 1991; isotype: US fragm. ex NY!).

Muhlenbergia peruviana fo. viridis Kuntze, Revis. Gen. Pl. 3(3):357. 1898. Type: Bolivia, Puna, 4000 m, 11 Mar 1892, Kuntze s.n. (lectotype: NY! designated by Peterson and Annable, Syst. Bot. Monogr. 31:73. 1991).

Muhlenbergia herzogiana Henrard, Meded. Rijks-Herb. 40:58. 1921. Type: Bolivia, Cordillera de Santa Bonita, Jun 1911, T. Herzog 2226 (holotype: L!; isotypes: US-87248 fragm. ex L!, US-1161342!, W-1926-23724!).

Description.

Tufted annuals. Culms 3-27 cm tall, erect, glabrous. Leaf sheaths usually longer than the internodes, smooth or scabridulous; ligules 1.5-3 mm long, membranous, acute; blades 1-5 cm long, 0.6-1.5 mm wide, flat to involute, smooth or scabridulous abaxially, sometimes shortly pubescent adaxially. Panicles 2-8 cm long, 0.3-3.4 cm wide, contracted or open; primary branches 1-5 cm long, diverging up to 80° from the rachises; pedicels 0.4-5 mm long, smooth or scabrous. Spikelets 1.4 4.2 mm long, 1-flowered; glumes smooth or scabridulous; lower glumes 0.8-2.8 mm long, narrow to broadly lanceolate, 1-veined, acute, often awn-tipped; upper glumes 0.9-3 mm long, wider than the lower glumes, lanceolate, 3 (2)-veined, truncate to acute, 2- or 3-toothed; lemmas 1.4-4.2 mm long, ovate, widest near the base, purplish mottled with dark green areas, hairy on the calluses and lower 2/3 of the lemma bodies, hairs to 0.5 mm long, apices acuminate, usually bifid and awned from between the teeth, teeth to 0.5 mm long, awns 3-10 mm long, flexuous, purplish; paleas 1.3-3.8 mm, narrowly lanceolate, acuminate to subacute; anthers 0.5-1 mm long, purplish to yellowish. Caryopses 1-1.6 mm long, fusiform, brownish. 2 n = 30.

Distribution.

Muhlenbergia peruviana occurs in Arizona and New Mexico, U.S.A, throughout Mexico to Guatemala and then in Argentina, Bolivia, Chile, Ecuador and Peru ( Peterson and Annable 1991).

Ecology.

Grassy flats, open gravelly flats, rock outcrops, sandy washes, gravelly drainages, wet or dry meadows, canyons, gravelly or sandy slopes, valleys, shores along lakes, open ridgetops and disturbed road cuts associated with Aciachne pulvinata Benth., Anatherostipa , Berberis , Calamagrostis spp., Colletia spinosissima , Ephedra , Festuca orthophylla Pilg., Festuca spp., Jarava , Juncus , Lepidophyllum , Luzula , Margyricarpus , Monnina , Muhlenbergia spp., Nassella , Plantago , Poa spp., Polylepis , Puya , Pycnophyllum , Salvia oppositiflora Ruiz & Pav., Stevia and Tagetes ; 3000-4900 m.

Comments.

As treated here, Muhlenbergia peruviana includes (as synonyms) what was sometimes identified as M. pulcherrima Scribn. ex Beal (south-western U.S.A. and northern Mexico) and M. pusilla Steud. (central Mexico to Guatemala). There are many more morphological forms than just these and since the only chromosome count of this species suggests triploidy (2 n = 3 × =30), perhaps this species is apomictic ( Reeder 1968). We believe apomixis is occurring in this species but it it not obligate and that gene flow takes place sporadically to form intermediates maintained by asexual seed formation ( Peterson and Annable 1991).

In a molecular DNA sequence analysis, Muhlenbergia peruviana is sister to M. crispiseta Hitchc., another annual known only from Texas and north-central Mexico and this pair is embedded in the strongly supported M. subg. Clomena clade ( Peterson et al. 2010b; Fig. 1B ). Members of M. subg. Clomena possess spikelets with upper glumes that are 3-veined and often 3-toothed and individuals with a densely caespitose habit ( Peterson et al. 2010b). Muhlenbergia peruviana can be separated from M. crispiseta in having irregularly flexuous, purplish awns (versus sinuous-wavy, crisped and curled, olive-green awns in M. crispiseta ) and narrow, gradually acuminate lemmas (versus lemmas that are plump near middle) [ Peterson and Annable 1991]. In our current DNA-derived phylogeny, M. crispiseta falls within the M. peruviana clade (Fig. 1B ). However, rps3, the single marker we have for M. crispiseta , is not variable enough to distinguish these two species that are easily separated morphologically. In the future, we hope to clarify this with a full set of markers for M. crispiseta .

Specimens examined.

Peru. Amazonas: Prov. Chachapoyas, Cerros Calla Calla, 3100 m, 19 Jun 1964, D.C. Hutchison & J.K. Wright 5756 (LIL, MO). Ancash: Cordillera Blanca, 4 km north of Recuay, 3400 m, 6 Apr 1988, S.A. Renvoize & S. Lægaard 5101 (CPUN, K); Cordillera Negra, 3 km N of Punta Callán, W of Huaraz, 4400 m, 7 Apr 1988, S.A. Renvoize & S. Lægaard 5171 (CPUN, K); Cordillera Negra, 30 km from Huaraz towards Casma, Punta Callán, 4200 m, 7 April 1988, S.A. Renvoize & S. Lægaard 5166 (CPUN, K); Pariarracra, Pampa de Lampas, 4160 m, 2 May 1952, E. Cerrate 1465 (MOL); Prov. Bolognesi, Capillapunta, 3350 m, 14 Apr 1949, R. Ferreyra 5716 (MOL, USM); Prov. Bolognesi, cerros al E de Chiquián, 3500 m, 10 May 1950, R. Ferreyra 7345 (US, USM); Prov. Bolognesi, Matarragra, cerro al NO de Chiquián, 3560 m, 8 Apr 1949, R. Ferreyra 5633 (US, USM); Prov. Bolognesi, Shincush, arriba de Chiquián, 4000 m, 19 Apr 1949, R. Ferreyra 5624 (US, USM); Carhuaz, Cordillera Negra, E slope, ca. 22 km SW of Shupluy, 09°17'19.7"S, 77°44'39.3"W, 3770 m, 13 Mar 2008, P.M. Peterson, R.J. Soreng, M.I. La Torre & J.V. Rojas Fox 21655 (US, USM); Recuay, Cordillera Blanca, 37 km E of Raquia on Route 02-014 on road towards Huarez, 3900 m, 20 Mar 1997, P.M. Peterson & N. Refulio Rodriguez 13818 (MO, US, USM); Recuay, Cordillera Negra W slope N of Quebrada Parin, 23 km NE of Cotaparaco on road to pass above Lago Ututo and Utcuyacu, 09°55'10.7"S, 77°32'02.2"W, 4216 m, 10 Mar 2008, P.M. Peterson, R.J. Soreng, M.I La Torre & J.V. Rojas Fox 21564 (US, USM); Recuay, Cordillera Negra, en cima de Caraz, 4300 m, A. Weberbauer 3098 (MOL); Huaraz, Huascarán National Park, quebrada Llaca, north side of valley, 9°27'S, 77°27'W, 4350 m, 25 May 1986, D.N. Smith 12428 (CPUN, MO); Recuay, quebrada Huanca, 9°55'S, 77°23'W, 3950 m, 2 Jul 1985, D.N. Smith & M. Buddensiek 10959 (CPUN, LPB, MO); Recuay, Huascarán National Park, mouth of quebrada Quenua Ragra, 10°2'S, 77°15'W, 4200 m, 10 May 1985, D.N. Smith, R. Valencia & A. Gonzales 10624 (CPUN, MO); Huari, Huascarán National Park, south side of quebrada Carhuazcancha, 9°28'S, 77°15'W, 3790 m, 6 May 1986, D.N. Smith, R. Valencia, A. Gonzales & M. Buddensiek 12294 (CPUN, MO); Recuay, 2 km SW of Conococha on Ruta 02-014, 10°8'18.2"S, 77°18'5.4"W, 4107 m, 21 Mar 2004, P.M. Peterson, N. Refulio Rodriguez, A. Cano, M.I. La Torre & I. Salinas 17903 (US, USM); Recuay, 3 km E of Conococha, 10°6'55.5"S, 77°16'20.2"W, 4050 m, 24 Mar 2004, P.M. Peterson & N. Refulio Rodriguez 17939 (MO, US, USM); Recuay. Huascarán National Park, Sector Querococha, above guardstation, 9°44'S, 77°20'W, 3875 m, 5 Jul 1985, D.N. Smith & M. Buddensiek 11045 (CPUN, LPB, MO); Yungay, Huascarán National Park, Llanganuco sector, Maria Josefa trail between Chinancocha and Pucuyacu, 9°5'S, 77°39'W, 3700-3850 m, 7 May 1985, D.N. Smith 10548 (CPUN, MO). Apurimac: Aymaraes, 24 km NE of Chalhuanca on road towards Yanaca, 14°15'26.4"S, 73°12'18.8"W, 4260 m, 13 Mar 2002, P.M. Peterson & N. Refulio Rodriguez 16506 (US, USM). Arequipa: Arequipa,10 km W of Patahuasi on road towards Arequipa, 16°4'37.3"S, 71°29'49.8"W, 4100 m, 11 Apr 2004, P.M. Peterson & N. Refulio Rodriguez 18243 (MO, US, USM); Arequipa, Jesus-Chiqüata, 2900 m, Jun 1977, C. Vargas C. s.n. (LIL); Arequipa, cerca a Chiquata, 3100 m, 31 Mar 1949, C. Vargas C. 8092 (CUZ, US); Caylloma, 10 km SE of Callalli on road towards Condoroma, 15°29'26"S, 71°23'5.9"W, 4340 m, 12 Apr 2004, P.M. Peterson & N. Refulio Rodriguez 18270 (MO, US, USM); Prov. Caylloma, Pampa Cañahuas. "Llapa pasto", 4200 m, 30 May 2001, M. Rodríguez Diaz 1126 (USM). Ayacucho: Marcahrasi, arriba de Puquio, 3400 m, 24 Apr 1950, R. Ferreyra 7215 (MOL, US, 8USM); Huamanga, S of Ayacucho ca. 23 km on Hwy 3 toward Abancay, 13°16'21.5"S, 74°13'46.8"W, 3575 m, 15 Mar 2007, P.M. Peterson, R.J. Soreng, K. Romashchenko & D. Susanibar Cruz 20497 (US, USM); Huamanga, S of Ayacucho ca. 27 km on Hwy 3 toward Abancay, 13°17'9.8"S, 74°13'41.9"W, 3684 m, 16 Mar 2007, P.M. Peterson, R.J. Soreng, K. Romashchenko & D. Susanibar Cruz 20508 (US, USM); Huanca Sancos, 16 km NW of Putajasa on road towards Huanca Sancos, 14°1'42.5"S, 74°16'16.6"W, 3900 m, 25 Feb 2002, P.M. Peterson, A. Cano, M.I. La Torre, A. Ramirez & D. Susanibar Cruz 16254 (US, USM); Lucanas, 13 km E of Puquio at km 172 mark, 14°41'18.5"S, 74°4'26.8"W, 3730 m, 8 Apr 2004, P.M. Peterson & N. Refulio Rodriguez 18213 (MO, US, USM); Lucanas, 25 km NE of Villatambo on road towards Lucanas at Reserva "Pampa Galeras", 14°40'46.2"S, 74°23'59.2"W, 3805 m, 8 Apr 2004, P.M. Peterson & N. Refulio Rodriguez 18181 (MO, US, USM); Pampalca, between Huanta and Rio Apurimac, 3200 m, 4 May 1929, E.P. Killip & A.C. Smith 22216 (US). Cajamarca: Cajamarca, S of Cajamarca ca. 9 air km, 7°14'8.1"S, 78°19'17.9"W, 3270 m, 27 Mar 2008, P.M. Peterson, R.J. Soreng, I. Sánchez Vega & J. Montoya Quino 21885 (US, USM); Cajamarca, Cerro Piedras Gachas, entre Yanacocha y Llaucán, 3900 m, 23 Apr 1994, I. Sánchez Vega 6997 & M. Cabanillas S. (CPUN); Cajamarca, entre Cajamarca y Cumbe Mayo, Fundo de la Universidad, 3450 m, 22 May 1971, I. Sánchez Vega 685 & M. Vilhena (CPUN); Cajamarca, entre Cajamarca y Cumbe Mayo, km 14, en el Arboretum Cumbe Mayo CICAFOR, 3400 m, 18 Apr 1981, I. Sánchez Vega 2466, V. Torrel & E. Medina (CPUN); Cajamarca, Dist. Cajamarca. Sais Atahualpa de Porcón en el Arboretum de CICAFOR, 3400 m, 16 May 1981, I. Sánchez Vega 2524, V. Torrel & E. Medina (CPUN); Cajamarca, Dist. Cajamarca, Cerro Gavilán, 3100 m, 26 Jun 1966, I. Sánchez Vega 238 (CPUN); Cajamarca, Dist. Cajamarca, Hacienda Porcón, a 35 km de Cajamarca, 3400 m, 31 May 1969, I. Sánchez Vega 401 (CPUN); Cajamarca, Dist. Cajamarca, Cerro Minas, Granja Porcón, 35 km al N de Cajamarca, 3900 m, 22 Jun 1994, I. Sánchez Vega 7293 & G. Bazan H. (CPUN); Cajamarca. Dist. Cajamarca, Tamiacocha, Cerro Negro, Gavilán, distancia 5 km en línea recta, queda a la vertiente occidental, 7°15'S, 78°28'W, 3558 m, 26 May 2001, I. Sánchez Vega 10618 (CPUN); Cajamarca, ladera que coverge a la Colpa, 2900 m, 22 Apr 1975, I. Sánchez Vega 1419, P. Brandelard, J. Sanabria & W. Ruiz Vigo (CPUN); Cajamarca, Corisorgona, al Norte de la ciudad de Cajamarca, carretera a Chamis, 3050 m, 25 Apr 1991, I. Sánchez Vega 5585 & A. Briones (CPUN); San Miguel, 61 km N of Cajamarca on hwy 3N towards Bambamarca, 3640 m, 16 Mar 2000, P.M. Peterson & N. Refulio Rodriguez 14913 (CPUN, MO, US, USM). Cusco: Prov. Calea, Uchumuca-Pisae, Apr 1994, F. Marin 386 (LIL); Calca, 20 km N of Calca on road towards Lares, 13°13'52.9"S, 71°54'26.5"W, 4060 m, 16 Mar 2002, P.M. Peterson & N. Refulio Rodriguez 16546 (US, USM); Prov. Canchis, temple of Viracocha near Tinta, 3500 m, 15 Apr 1913, O.F. Cook & G.B. Gilbert 211 (US); Prov. Cusco, Ruinas Sacsahramán, 3500 m, 6 May 1983, S.G. Beck 8366 (LPB, MO); Prov. Cusco, Tambomachay, 3700 m, Apr 1949, F. Marin 1420 (US, LIL); Prov. Cusco, Cusco–Huancar, 3500 m, 18 Jun 1982, Gutte and Miller 9424 (USM); Prov. Espinar, alrrededores de Youri, 3900 m, 26 Mar 1956, C. Vargas C. 11210, 11211 (CUZ, US); Prov. Espinar, Hacienda C’uyo, 4200 m, 24 Mar 1956, C. Vargas C. 11180 (CUZ, US); Prov. Espinar, Hacienda C’achachi, 4200 m, 20 Mar 1956, C. Vargas C. 11151, 11163 (CUZ, US); Prov. Paucartambo, 1936, J. Soukup s.n. (US); Prov. Paucartambo, Acjanacu, 3600 m, 6 Jul 1948, C. Vargas C. 7299 (CUZ, US); Prov. Paucartambo, Yanamayo, 9 Jul 1946, C. Vargas C. 609 (CUZ, US); Quispi canchi, 23 km up new hwy 28 from Urcos to Ccatcca (Catsa), ESE of Cusco ca. 45 air km, 13°39'39"S, 71°35'29.7"W, 4080 m, 19 Mar 2007, P.M. Peterson, R.J. Soreng & K. Romashchenko 20563 (MO, US, USM); Prov. Urubamba, quebrada Pumahuanca, 3200 m, 31 Dec 1962, H.H. Iltis & C.M. Iltis 1014 (LIL). Huancavelica: Castrovirreyna, 4 km S of Choclococha and 8 km N of Santa Ines, 13°10'44"S, 75°5'15.3"W, 4615 m, 5 Apr 2004, P.M. Peterson & N. Refulio Rodriguez 18147 (MO, US, USM); Huancavelica, Huancavelica, 4000 m, 8 Apr 1961, O. Tovar 3171 (MO, USM); Huancavelica, 56 km S of Izacuchaca on road towards Huancavelica, 4020 m, 10 Apr 1997, P.M. Peterson & O. Tovar 14160 (MO, US, USM); Huancavelica, 12 km S of Huancavelica on road towards Santa Barbara, 4120 m, 11 Apr 1997, P.M. Peterson & O. Tovar 14189 (MO, US, USM); Huancavelica, Sachahuajta, a 6 km de Conaica, 3600 m, 3 Apr 1952, O. Tovar 944 (US, USM); Huancavelica, Huando, 3600 m, 6 Apr 1953, O. Tovar 1277 (US, USM); Huancavelica, Canyon of Rio Ichu, SW of Huancavelica ca. 5 km on hwy 3 to Santa Ines and Ayacucho, 12°48'48.2"S, 75°3'24.5"W, 4894 m, 14 Mar 2007, P.M. Peterson, R.J. Soreng, K. Romashchenko & D. Susanibar Cruz 20464 (MO, US, USM); Huaytara, along Rio Pampas, along hwy 3 (old 24), 12 km NW of jct with new hwy 24 and 18 km SE of Santa Ines, SE of Pilpichaca, 13°19'24.2"S, 75°0'56.6"W, 4164 m, 13 Mar 2007, P.M. Peterson, R.J. Soreng, K. Romashchenko & D. Susanibar Cruz 20438 (US, USM); Huaytara, 7 km W of Pilpichaca on road towards Huancavelica. 13°18'46.5"S, 75°2'7"W, 4250 m, 5 Apr 2004, P.M. Peterson & N. Refulio Rodriguez 18157 (MO, US, USM); Tayacaja, just above Chuquitambo, 4 km SW of Pazos, 3975 m, 9 Apr 1997, P.M. Peterson & O. Tovar 14150 (MO, US, USM); Tayacaja, arriba de Hacienda Tocos, entre Colcabamba y Paucarbamba, 3700 m, 20 Apr 1954, O. Tovar 1961, 2013 (US, USM); Tayacaja, Hacienda Huari, 3700 m, 10 Aug 1949, O. Velarde Nuñez 2038 (US, USM). Huanuco: 18 mi SE of Huanuco, 31 May 1922, J.F. Macbride & W. Featherstone 2114 (F, US); Junín: Prov. Cerro, Goyllarisquisca, 4100 m, 22 Jun 1940, E. Asplund (US); Prov. Huancayo, Acopalca, 3800 m, 20 Jul 1943, J. Infantes Vera 412 (LIL); Prov. Concepción, Cani, 7 mi NE of Mito, 2800 m, 16 Apr 1923, J.F. Macbride 3401 (F, US); Prov. Huancayo, Laive, 3600 m, 15 Mar 1947, J. Infantes Vera 920 (LIL); Prov. Jaupa, 6 km a Concepción, quebrada de Iscos, 3300 m, Mar 1947, C. Ochoa 81 (LIL, MOL, USM); Prov. Yauli, La Oroya, 3950 m, 27 May 1922, J.F. Macbride & W. Featherstone 984 (F, US); Prov. Yauli, Yauli, 4450 m, 25 May 1922, J.F. Macbride & W. Featherstone 916 (F, US). La Libertad: Prov. Otuzco, Purrupumpa, 3585 m, 15 May 1991, S. Leiva, P. Leiva & E. Zavaleta 273 (HAO); Prov. Stgo. Chuco, Cerro La Botica, arriba de Cachicadán, 3050 m, 10 Jun 2001, A. Sagastegui, S. Leiva & M. Zapata 16685 (HAO). Lambayeque: Ferrenafe, 3300 m, 29 Jun 1996, S. Llatas Quiroz 4121 (MO). Lima: arriba de Sucro, 3000 m, 1 May 1948, R. Ferreyra 3445 (MOL, US, USM); Prov. Huarochiri, Matucana, 13 Apr 1922, J.F. Macbride & W. Featherstone 450 (F, US). Moquegua: Carumas, 3200 m, 21 Feb 1925, A. Weberbauer 7295 (US); 1 km S of Puentes Vizcachas, 32 km NE of Humajalso and 18 km S of Titiri, 16°37'14.8"S, 70°24'50.2"W, 4310 m, 18 Apr 2004, P.M. Peterson & N. Refulio Rodriguez 18317 (MO, US, USM). Pasco: Pasco, 4 km NE of Huayllay on road to wards Canchacucho at "Bosque de Piedras", 10°58'20.8"S, 76°19'18"W, 4160 m, 31 Mar 2004, P.M. Peterson & N. Refulio Rodriguez 18068 (MO, US, USM). Piura: Huancabamba, abajo del Tabo, 3 Jul 1961, C. Acleto 313 (USM). Puno: Araranca, 4100 m, 21 Apr 1925, F.W. Pennell 13466 (US); W of Llave, 3900 m, 21 Jul 1946, O.P. Pearson & A. Pearson 8 (US); Prov. Carabaya, Ockopuno, 4800 m, Apr 1949, C. Vargas C. 8142 (CUZ, MO, US); Cerro Orco Pata, 4000 m, 17 Jan 1964, R.A. Arevalo 27 (LIL); Prov. Carabaya, Fauchinta Allinccapac, 4600 m, 1 Apr 1948, C. Vargas C. 7157 (CUZ, US); Provincia Lampa, distrito Pucará, inmediaciones del pueblo de Chijnaya, en sustratos arenoso-rocosos en los bordes de la carretera, 4000 m, 14 Jul 2013, D. Giraldo-Cañas 5532 (COL); Pucará, lugar Chijnaya, 3990 m, Mar 1964, A. Vera 108 (COL); Hacienda Iriapata, estación Pucará, 3990 m, Oct 1963, A. Vera s.n. (COL); Chuquibambilla, 3900 m, 19 Apr 1925, F.W. Pennell 13375-1 (US); Chucuito, 2 km S of Huacullani, 4000 m, 6 Mar 1999, P.M. Peterson, N. Refulio Rodriguez & F. Salvador Perez 14660 (MO, US, USM); Chucuito, 5 km S of Huacullani on road towards Kelluyo, 4250 m, 6 Mar 1999, P.M. Peterson, N. Refulio Rodriguez & F. Salvador Perez 14679 (MO, US, USM); Chucuito, 27 km NW of San Jose Ancomarca, 4280 m, 8 Mar 1999, P.M. Peterson, N. Refulio Rodriguez & F. Salvador Perez 14702 (MO, US, USM); El Collao, 34 km E of El Cruce and 24 km W of Mazo Cruz, 4180 m, 2 Mar 1999, P.M. Peterson, N. Refulio Rodriguez & F. Salvador Perez 14595 (MO, US, USM); Lampa, NW end of Laguna Lagunillas, 20 air km W of Santa Lucia, 74 air km WSW of Juliaca, 15°41'1.7"S, 70°48'5.4"W, 4185 m, 31 Mar 2007, P.M. Peterson, R.J. Soreng, K. Romashchenko & M.S. Gonzalez Elizondo 20738 (US, USM); Prov. Lampa, Pucará, A. Weberbauer 415 (US); Melgar, ca. 7 km WNW of Santa Rosa on hwy 3 and 1 km W towards Quishuara, along Rio Santa Rosa, 14°35'54.9"S, 70°51'34.7"W, 4002 m, 23 Mar 2007, P.M. Peterson, R.J. Soreng & K. Romashchenko 20604 (MO, US, USM); Puno, 2 km N of Laraquerion on road towards Puno, 16°6'59.1"S, 70°1'59.1"W, 3940 m, 18 Apr 2004, P.M. Peterson & N. Refulio Rodriguez 18329 (MO, US, USM); San Roman, 4 km E of Santa Lucia, along Rio Cabanillas, 15°41'4.2"S, 70°34'8.8"W, 4030 m, 19 Apr 2004, P.M. Peterson & N. Refulio Rodriguez 18334 (MO, US, USM); San Roman, 21 km W of Santa Lucia and 5 km E of Puente Cañuma (Laguna Lagunillas), 15°40'4.1"S, 70°47'4.4"W, 4260 m, 20 Apr 2004, P.M. Peterson & N. Refulio Rodriguez 18341 (MO, US, USM).

Figures

Figure 1. A, B Maximum-likelihood tree inferred from combined plastid (ndhA intron, rps 16 - trnK, rps 16 intron, rps 3, and rpl 32 - trnL) and ITS sequences. Thick branches indicate posterior probabilities of 0.95 - 1; species in red occur in South America; scale bar = 2 %.

Figure 11. A-D Muhlenbergia peruviana (P. Beauv.) Steud A habit B ligule C glumes D floret E, F Muhlenbergia phalaroides (Kunth) P. M. Peterson E panicle F spikelet. Drawings A-D from Peterson and Annable (1991) drawn from P. M. Peterson & C. R. Annable 4739 (WS) E, F from Giraldo-Canas and Peterson (2009) drawn from S. Laegaard 71419 (AAU).