Tragus peruvianus Muñuico, Quip. & Gut.Peralta, 2025

Muñuico, Jhon W., Quipuscoa-Silvestre, Victor & Gutiérrez, Harol, 2025, Synopsis of the genus Tragus (Poaceae: Chloridoideae: Cynodonteae) in Peru, Phytotaxa 698 (3), pp. 140-154 : 146-151

Tragus peruvianus Muñuico, Quip. & Gut.Peralta , sp. nov. ( Figs. 2A–D , 3 )

Type:— PERU. Arequipa: Provincia Islay, Distrito Mejía, Lomas de Mejía, Formación de lomas, 17°5'21.2''S, 71°53'18.4''W, 263 m, 1 November 2017, V. Quipuscoa S., M. O. Dillon, C. Tejada P., M. Balvin A., S. Huamaní Q., M. Bedoya C., C. Sanz N. & M Flores M. 6363 (holotype HSP 17786!, isotypes HSP 17787!, HUSA 21579!, HUT 65648!).

Diagnosis: — Tragus peruvianus differs from other species of Tragus by the following combination of characters: culms non-stoloniferous; panicles with a striated primary rachis, pubescent to strigose; fascicles typically with 2 spikelets, with 3–4 spikelets occurring in 1–4 basal fascicles; basal fascicle rachis always terete and pubescent; upper glume 7- veined, with tubercle-based hooked hairs 0.2–0.6 mm long, antrorsely inclined, with the basal width equal to 1/3 of the hair length; lemma 2–3.1(–3.5) mm long.

Description: —Annual, caespitose, erect to suberect. Culms 3–30 cm tall, generally geniculate, with basal branching; nodes 3–5, glabrous, brown-violet, occasionally with basal nodes rooting; internodes glabrous, yellow-green to violet. Sheaths glabrous, with pilose margins near the apex (hairs up to 1.5 mm long). Ligules 0.4–1 mm long, ciliate. Blades (0.5–)1–4 × 0.2–0.5 cm, flat, linear-lanceolate, acute, glabrous to glabrescent toward the apex, with thickened margins and hooked hairs up to 1.5 mm long. Panicles 2–8 × (0.5–) 0.6–1.1 cm, terminal, dense, spiciform, green to green-violet; primary rachis striated, pubescent to strigose (hairs up to 2 mm long). Fascicles typically with 2 spikelets, the basal ones with 3–4, 3–5.2(–5.9) × 1–2 mm, deciduous; secondary rachis 0.4–1.5(–2.3–4) mm long, terete, pubescent to strigose, sometimes with tubercle-based hooked hairs (hairs up to 0.5 mm long); proximal internode 0.2–1(–1.5) mm long, second internode 0.2–0.8 mm long, third 0.2–1.3 mm long, rarely present, fourth when present, (0.1–) 0.5–1.7 mm long. Proximal spikelet (2.7–)2.8–4.5(–4.8) × (0.5–) 0.7–1.2 mm, 1-flowered, fertile, dorsiventrally compressed; lower glume 0.3–0.9 × 0.2–0.5 mm, veinless, membranous, hyaline, deltoid to oblong, acute or truncate, sometimes irregularly denticulate at the apex, scabrous; upper glume (2.7–)2.8–4.5(–4.8) × 0.8–1.8 mm, 7-veined, coriaceous, ovate-lanceolate, acuminate, scabrous to pubescent in inter-nerval spaces, veins with (4–)6–12 tubercle-based hooked hairs (0.2–0.6 mm long, basal width equal to 1/3 of length); lemma 2–3.1(–3.5) × 0.8–1.3 mm, 3- veined, membranous, ovate-lanceolate, acute, acuminate, or mucronate (0.1–0.3 mm long), glabrescent dorsally; palea (1.4–)1.5–2.5(–2.7) × 0.6–1.2 mm, 2-veined, membranous, hyaline, oblong, truncate, irregularly denticulate at the apex, glabrous or scabrous; lodicules 2, 0.4–0.5 × 0.2–0.3 mm, membranous, hyaline, cuneate, truncate; anthers 3, 0.3–0.7 mm long, yellow or violet. Second spikelet (1.8–)2.2–4.3 × (0.3–) 0.6–1.2 mm, similar to the proximal spikelet, generally fertile; lower glume (0.2–)0.3–0.9 × 0.2–0.4 mm; upper glume (1.8–)2.2–4.3 × 0.7–1.6 mm, 7–veined, veins with 5–11 tuberculate–based hooked hairs (hairs 0.2–0.5 mm long); lemma 2–3.1 × 0.8–1.5 mm, 3–veined; palea 1.5–2.2 × 0.8–1.2 mm, 2–veined; lodicules 2, 0.3–0.5 × 0.2–0.3 mm; anthers 3, 0.3–0.7 mm long. Third spikelet rarely present, 0.5–2.2(–3.3) × 0.3–1 mm, reduced to the upper glume. Fourth spikelet rarely present, 0.8–1.2 × 0.2–0.3 mm, reduced to the upper glume. Caryopsis 1.2–1.8(–1.9) × (0.3–) 0.5–0.8 mm, dorsiventrally flattened, ellipsoid; embryo (0.3–)0.5–0.8 × 0.3–0.5 mm, oblong to rounded.

Common names: —"pega pega".

Etymology: —The specific epithet refers to Peru.

Distribution and habitat: —Occurs in the lomas formations, Tillandsia fields, and western slopes of southern Peru, in Arequipa, Ica, Lima, Moquegua, and Tacna departments ( Fig. 1). It grows in arid environments with sandy, occasionally clayey or rocky soils, at elevations of 15–2675 m. It primarily coexists with Aristida adscensionis , Atriplex rotundifolia Dombey ex Moquin-Tandon (1840: 70) , Cenchrus sp. , Chenopodium petiolare Kunth (1817: 191) , Eragrostis sp. , Jarava annua ( Mez 1921: 204) Peñailillo (2002: 30) , Tillandsia purpurea Ruiz & Pavon (1802: 41) , Solanum edmondstonii Hooker (1847: 201) , and other species typical of lomas formations. Dispersal occurs through zoochory, facilitated by morphological adaptations of the upper glume.

Phenology: —Flowering and fruiting occur during the wet season: March–April in western valleys and September– December or until January–May during El Niño events in lomas and Tillandsia fields.

Notes: —This species shares the 7-veined upper glume character with Tragus heptaneuron Clayton (1972: 151) and T. racemosus ( Fig. 3 , Table 1), but is phylogenetically distinct from both species and more closely related to T. andicola (which has a 5-veined upper glume), as indicated by analyses of specimen F.L.S.P. 457, identified here as T. peruvianus ( Peterson et al. 2016) . According to taxonomic reviews ( Anton 1981, Barkworth et al. 2003), and observations of specimens J. R. Reeder & C. G. Reeder 7619 (USM!) and J. R. Reeder & C. G. Reeder 7668 (USM!), T. racemosus has stoloniferous culms, somewhat lax panicles, a terete and inconspicuously striated panicle axis base, which is glabrous or glabrescent, fascicles with 3–5 (rarely 2) spikelets, and lemma 3.2–4 mm long. In contrast, T. peruvianus usually has spiciform panicles, a densely pubescent or strigose panicle axis base, fascicles with 2 (rarely 3–4) spikelets, and lemma 2–3.1(–3.5) mm long ( Fig. 2A–D , 3A–I ). Furthermore, T. heptaneuron has fascicles with paired spikelets, an upper glume bearing retrorsely inclined, slender hooked hairs, and a basal width/length ratio of developed hooked hairs (1/3–)1/4–1/6 ( Clayton 1972). In contrast, T. peruvianus has fascicles with unpaired spikelets, an upper glume with antrorsely inclined, thick hooked hairs, and a basal width/length ratio of developed hooked hairs 1/1–1/3 ( Fig. 2C–D , 3C–F ).

Additional material examined (paratypes): — PERU. Arequipa: Prov. Arequipa, Tingo , 2450 m, 23 March 1967 (fl,fr), C. Vargas 19145 ( CUZ!) ; Socabaya, faldas de los cerros del Batolito de La Caldera , 16°28'4176'' S, 71°32'39.87''W, 2675 m, 4 March 2012 (fl, fr), A. Pauca T. 83 ( HSP!) ; Prov. Camaná, 30 Km antes de Ocoña , 300 m, 5 December 1997 (fl, fr), F. L. S. P. 457 ( HUSA!, US!, USM!) ; entre Camaná y Ocoña , 300–350 m, 13 November 1952 (fl, fr), R. Ferreyra 8863 ( USM!) ; entre Ocoña y Camaná , 300–350 m, 13 November 1949 (fl, fr), R. Ferreyra 6457 ( USM!) ; Lomas de Cerrillo , 16°35'54.17'' S, 72°44'4''W, 296 m, 8 November 2014 (fl, fr), F. Cáceres 7368 ( HUSA!) ; Lomas de Cerrillo , 16°37'37.57''S, 72°38'47.39''W, 253 m, 27 September 2015 (fl, fr), F. Cáceres 7774 ( HUSA!) ; Ocoña, Alto Chira , 400 m, 18 March 1998 (fl, fr), F. L. S. P. 1864 ( HUSA!) ; Alto Chira , 400 m, 18 March 1998 (fl, fr), C. Vargas 1864 ( CUZ!) ; Lomas de Chira, 16°29'25.75''S, 73°1'34.64''W, 280 m, 9 November 2021 (fl, fr), J. Muñuico M. & M. Bedoya C. 922 ( HSP!) ; Samuel Pastor, Lomas de Camaná, 16°39'13.90''S, 72°37'34.84''W, 90 m, 12 November 2021 (fl, fr), J. Muñuico M. 956 ( HSP!) ; Prov. Caravelí, Atico , 100 m, 16 November 1957 (fl, fr), O. Tovar 2668 ( USM!) ; Atico , 5–15 m, 10 November 1949 (fl, fr), R. Ferreyra 6368 ( USM!) ; Atico, ca. al Km 723 de la panamericana sur, 16°16'8.40''S, 73°30'19.84''W, 43 m, 9 November 2021 (fl, fr), J. Muñuico M. & M. Bedoya C. 895 ( HSP!) ; Atico, ca. Km 697 de la panamericana sur-Chorrillos, 16°12'42.89''S, 73°42'15.60''W, 49 m, 8 November 2021 (fl, fr), J. Muñuico M. & M. Bedoya C. 853 ( HSP!) ; Atiquipa, Atiquipa , 15°42'S, 74°24'W, 400 m, 19 March 1998 (fl, fr), F. L. S. P. 1987 ( HUSA!) ; Atiquipa , 17 November 1957 (fl, fr), O. Tovar 2726 ( USM!) ; Lomas de Atiquipa, ca. 10.5 Km N of turn-off to Atiquipa. Km 584 S of Lima, 150–200 m, 1 November 1983 (fl, fr), M. O. Dillon & D. Dillon 3797 ( F!) ; Lomas de Atiquipa, ca. 10.5 Km N of turn-off to Atiquipa. Km 584 S of Lima , 270–600 m, 2 November 1983 (fl, fr), M. O. Dillon & D. Dillon 3822 A ( F!) ; Lomas de Atiquipa, 15°45’48.78’’S, 74°20’59.99’’W, 538 m, 14 December 2020 (fl, fr), J. Muñuico M. et al. 746 ( HSP!) ; Lomas de Atiquipa, 15°47’9.32’’S, 74°24’27.59’’W, 323 m, 4 November 2021 (fl, fr), J. Muñuico M. & M. Bedoya C. 768 ( HSP!) ; Lomas de Atiquipa, 15°47’39.16’’S, 74°24’34.75’’W, 312 m, 4 November 2021 (fl, fr), J. Muñuico M. & M. Bedoya C. 770 ( HSP!) ; Lomas de Atiquipa, 15°48’42.42’’S, 74°23’16.66’’W, 157 m, 4 November 2021 (fl, fr), J. Muñuico M. & M. Bedoya C. 774 ( HSP!) ; Lomas de Atiquipa, 15°47’31.06’’S, 74°19’10.21’’W, 314 m, 6 November 2021 (fl, fr), J. Muñuico M. & M. Bedoya C. 814 ( HSP!) ; Lomas de Atiquipa, 15°48’22.74’’S, 74°18’54.58’’W, 224 m, 6 November 2021 (fl, fr), J. Muñuico M. & M. Bedoya C. 817 ( HSP!) ; Lomas de Atiquipa, 15°48’3.58’’S, 74°20’51.99’’W, 389 m, 6 November 2021 (fl, fr), J. Muñuico M. & M. Bedoya C. 826 ( HSP!) ; Atiquipa, parte baja de las Lomas de Taimara, 15°48’34.73’’S, 74°21’32.98’’W, 243 m, 15 November 2014 (fl, fr), A. Pauca T. 521 ( HSP!) ; Atiquipa, Taimara , 17°50’ S, 74°0’ W, 200–660 m, 7 December 1997 (fl, fr), F. L. S. P. 642 ( HUSA!) ; Atiquipa, Taimara , 15°42’S, 74°24’W, 350–450 m, 16 March 1998 (fl, fr), F. L. S. P. 1699 ( HUSA!) ; Lomas de Atiquipa , 400–600 m, 5 September 1953 (fl, fr), C. Vargas 10933 ( CUZ!) ; Chala, al sur de Chala, 15°52’S, 74°11’W, 230 m, 15 November 2005 (fl, fr), M. O. Dillon et al. 8889 ( F!, HSP!, HUSA!) ; Chala 25 Km hacia Lima cerca Atiquipa , Aguas Saladas , 400 m, 13 March 1983 (fl, fr), G. Beck 7927 ( US!) ; Cháparra, Cháparra , 300 m, 19 October 1946 (fl, fr), R. Ferreyra 1473 ( US!, USM!) ; Capac, cerca a Chala , 40 m, 17 November 1957 (fl, fr), O. Tovar 2695 ( USM!) ; Lomas de Capac, 15°51’36.94’’S, 74°10’42.92’’W, 253 m, 23 December 2020 (fl, fr), J. Muñuico M. 748 ( HSP!) ; Lomas de Capac, 15°51’46.52’’S, 74°11’24.37’’W, 224 m, 7 November 2021 (fl, fr), J. Muñuico M. & M. Bedoya C. 846 ( HSP!) ; Lomas de Capac , 300 m, 18 October 1946 (fl, fr), R. Ferreyra 1436 ( US!, USM!) ; Bella Unión, Lomas de Bella Unión—Mochico , 15°22’44.78’’S, 74°43’51.03’’W, 544 m, 4 November 2021 (fl, fr), J. Muñuico M. & M. Bedoya C. 764 ( HSP!) ; Lomas de Bella Unión—Pan de Azucar , 15°24’37.06’’S, 74°43’18.86’’W, 348 m, 4 November 2021 (fl, fr), J. Muñuico M. & M. Bedoya C. 761 ( HSP!) ; Lomas de Bella Unión , 15°25’4.15’’S, 74°42’59.69’’W, 318 m, 25 November 2020 (fl, fr), J. Muñuico M. & D. Quispe S. 543 ( HSP!) ; Lomas, Loma cerca a Lomas , 390 m, 13 November 1957 (fl, fr), N. Angulo 2548 ( HUT!) ; Lomas de Jahuay, ca. 51 Km NW of Chaviña, 15°26’1’’S, 74°53’28’’W, 300 m, 7 February 1983 (fl, fr), M. O. Dillon et al. 3218 ( CPUN!, F!, HUT!, US!, USM!) ; Lomas de Jahuay, entre Nasca-Chala , 300–400 m, 2 May 1983 (fl, fr), R. Ferreyra et al. 19859 ( USM!) ; Prov. Castilla, Packaichacra , 1700 m, 23 April 1967 (fl, fr), C. Vargas 19373 ( CUZ!). Prov. Islay, arriba de Mejía, al sur de Mollendo, 180–200 m, 12 November 1949 (fl,fr), R. Ferreyra 6392 ( USM!) ; Mejía, Lomas de Mejía, 17°4'59.04''S, 71°53'23.67''W, 307 m, 18 November 2021 (fl, fr), J. Muñuico M. & M. Bedoya C. 1034 ( HSP!, HUT!) ; Mollendo , 17 November 1923 (fl, fr), A. S. Hitchcock 22352 ( F!, US!) ; Mollendo, Quebrada Catarindo, 16°58'48''S, 72°0'14''W, 400–550 m, 3 February 1998 (fl, fr), F. L. S. P. 925 ( HUSA!). Prov. La Unión , Quechualla, Huaña ca. a Quechualla, 15°18'19.17''S, 73°3'7.69''W, 1634 m, 9 March 2018 (fl, fr), V. Quipuscoa S. et al. 7090 ( HSP!). Ica: Prov. Nazca, San Juan de Marcona , Lomas de Marcona , 15°21'17.01''S, 75°2'38.52''W, 492 m, 6 March 2020 (fl, fr), A. Orellana et al. AO-833 ( USM!) ; San Juan de Marcona, Tillandsial Marcona , La Justa, 15°12'7.31''S, 75°2'6.19''W, 779 m, 23 February 2021 (fl, fr), A. Orellana et al. AO-1011 ( USM!) ; Marcona, a 10 Km de la carretera Panamericana , hacia Marcona , 520 m, 25 November 2016 (fl, fr), P. Gonzáles 3993 ( USM!) ; Marcona, Lomas de San Fernando, 15°6'49''S, 75°18'16''W, 684 m, 31 October 2012 (fl, fr), O. Whaley et al. KPP-13 ( USM!). Lima : cerca Km 56, carretera central, 1100–1300 m, 27 March 1946 (fl, fr), R. Ferreyra s.n. ( USM 215856 !) ; cerros al Norte de Chosica , 700–1000 m, 8 April 1923 (fl, fr), A. Weberbauer 10502 ( USM!). Prov. Huarochirí, Km 56 carretera central entre Chosica y Surco, 1300 m, 28 March 1946 (fl, fr), R. Ferreyra 631 ( USM!) ; Matucana, 16 April 1967 (fl, fr), J. López G. 4259 ( USM). Moquegua : Prov. General Sánchez Cerro , Omate , abajo de Omate carretera a Quinistaquillas , 16°45'0.37''S, 70°59'59.38''W, 1467 m, 22 March 2008 (fl, fr), V. Quipuscoa S. 3687 ( HSP!) ; Prov. Moquegua, Lomas de Ilo, 250–400 m, 28 October 1966 (fl, fr), C. Vargas 18016 ( CUZ!). Tacna: Prov. Locumba , Lomas de Sama , 300 m, 15 October 1976 (fl, fr), C. Vargas 22894 ( CUZ!) ; Prov. Tacna, 29–32 Km WNW of Tacna on Panamericana Hwy. ( Pampa Sama ), Km 1241–1247, 550– 630 m, 14 November 1986 (fl, fr), M. O. Dillon et al. 4767 ( F!, HUT!, USM!) ; ca. 21 Km SE of Moquegua / Tacna border, at Km 1225 S of Lima , 850-900 m, 16 February 1983 (fl, fr), M. O. Dillon et al. 3391 ( F!, USM!) ; carretera Panamericana Km 1247, entre Caimara y Tomasiri, 600 m, 28 September 1980 (fl, fr), A. Muller 3619 ( USM!) ; Lomas de Camiara , 17° 51' 87'' S, 71° 0' 50'' W, 50 m, 7 October 2002 (fl, fr), J. V. Schneider et al. 2787 ( USM!) ; Lomas a 70 Km de Tacna ( Norte ), 600–700 m, 1 December 1955 (fl, fr), R. Ferreyra 11634 ( US!, USM!) ; Lomas cerca al Morro Sama , 500–600 m, 6 October 1957 (fl, fr), R. Ferreyra 12545 ( USM!) ; Lomas de Sama Grande , 500–600 m, 4 October 1957 (fl, fr), R. Ferreyra 12503 ( USM!) ; Lomas de Sama , 500–600 m, 28 October 1966 (fl, fr), C. Vargas 18047 ( CUZ!) ; Lomas de Sama , 700–800 m, 10 May 1983 (fl, fr), R. Ferreyra et al. 8645 ( USM!) ; Lomas de Sama, Kms 1223–1224, 700–800 m, 1 May 1983 (fl, fr), R. Ferreyra et al. 19820 ( USM!) ; Lomas de Samas, altura desvío a Yaras , 550–1050 m, 13 December 1998 (fl, fr), A. Cano et al. 8030 ( USM!) ; Sama, Sama , 17°46'7.71''S, 70°29'6.99''W, 650 m, 1 November 2018 (fl, fr), G. Xue-Jun et al. 18024 ( USM!) .

Taxonomic Notes: —After a thorough review of the genus and the analysis of relevant specimens, the species listed below have been excluded from the agrostological flora of Peru:

Tragus australianus Blake (1941: 12) . Type:— AUSTRALIA. Queensland: Maranoa, Noondoo, near Dirranbandi, ca. 550 ft, 4 March 1936, S. T. Blake 10660 (holotype BRI!, isotypes CANB!, K 000674266!, MEL!).

In De Egea et al. (2016), Tragus australianus was cited for the first time with the specimen D. N. Smith 6153 (CTES). However, upon analysing the duplicate of the collection deposited in the USM herbarium (USM 164948!), it exhibits fascicles with the proximal internode smaller than the second internode, distal spikelets that are sterile and occasionally fertile—characteristics of T. berteronianus . Tragus autralianus has fascicles with the proximal internode longer than the second internode, and the distal spikelets are usually fertile ( Anton 1981, Sulekic & Zapater 2001, Barkworth et al. 2003, Egea et al. 2016).

Tragus racemosus (L.) Allioni (1785: 241). Cenchrus racemosus Linnaeus (1753b: 1049) . Type:—“Habitat in Europa australioris maritimis” (lectotype UPS [Herb. Burser 1: 5], designated by Scholz in Cafferty et al. (2000: 249).

In Peru, Tovar (1993) and Davidse & Brako (1993) reported the presence of Tragus racemosus with the specimens M. O. Dillon et al. 3391 and R. Ferreyra 12503, both collected in the department of Tacna. However, their morphological characteristics correspond to T. peruvianus . Tragus racemosus has stoloniferous culms, somewhat lax panicles, a terete and inconspicuously striated base of the panicle axis, which is glabrous or glabrescent, and fascicles with 3–5 (rarely 2) spikelets ( Anton 1981, Barkworth et al. 2003).

Material examined: — USA. Arizona: Cochise County, Chiricahua Mts, summit of Rucker Canyon Road , 1830 m, 14 October 1983 (fl, fr), J. R. Reeder & C. G. Reeder 7619 ( USM!) ; Pima county, ca. 23 Km east of continental in the Santa Rita Range Experiment Station area along the Greaterville-Continental Road , 1310 m, 6 September 1984 (fl, fr), J. R. Reeder & C. G. Reeder 7668 ( USM!) .

Figures

FIGURE 2. Tragus species in Peru. A–D. Tragus peruvianus, from V. Quipuscoa S. et al. 6363 (HSP-17786). A. Habit. B. Panicle. C. Basal fascicles with more than two spikelets. D. fascicles with two spikelets. E–F. Tragus berteronianus. E. Common fascicles, from C. Vargas 19177 (CUZ-37189). F. Unusual fascicles, from M. I. La Torre 747 (USM-195335). Photographs by Jhon W. Muñuico.

FIGURE 3. Tragus peruvianus. A. Habit. B. Ligule. C. Basal fascicles with more than two spikelets. D. Fascicles with two spikelets. E. Lower glume. F. Upper glume. G. Lemma. H. Palea, lodicules, gynoecium, and androecium. I. Caryopsis. From the holotype (V. Quipuscoa S. et al. 6363, HSP-17786). Drawn by Maricruz Bedoya C.