Xenophyllum digitatum (Wedd.) V.A.Funk, Novon 7(3): 239. 1997.

Calvo, Joel & Moreira-Munoz, Andres, 2020, Taxonomic revision of the Andean genus Xenophyllum (Compositae, Senecioneae), PhytoKeys 158, pp. 1-106 : 1

16. Xenophyllum digitatum (Wedd.) V.A.Funk, Novon 7(3): 239. 1997.

Werneria digitata Wedd., Chlor. Andina 1: 86. 1856. Type. Bolivia. Potosí: del nivel de las nieves de la quebrada de las lagunas de Potosí, Mar [without year], A. d’Orbigny 1407 (lectotype: P-02088550 (digital image!), designated by Funk (1997a: 239); isolectotypes: BR s.n.!, F-102321 (fragment!), P-02088551 (digital image!)).

Werneria digitata var. lanata Rockh., Bot. Jahrb. Syst. 70: 287. 1939. Type. Peru. Junín: An der Lima-Oroya-Bahn, hacienda San Florenzi bei Yauli, 4700 m, ["Jan 1902" according to the protologue], A. Weberbauer 356 (lectotype: G-00237251 (digital image!), designated here), syn. nov.

Description.

Suffruticose plant, forming clumps of erect stems. Rhizomes 5-12 × 0.5-0.9 cm, horizontal to oblique, glabrous. Stems 10-13 cm tall, simple or branched, glabrous, usually with leaves restricted to the upper part. Leaves imbricate, extending into a glabrous sheath-like base; leaf laminas 7.7-11.5 × 2.8-6.7 mm, linear-spatulate (broadened upwards), 3-forked at the apex (incision depth 1/3-1/2 of the total length), entire, usually with some minute cilia in the lower half, flat to elliptic or almost terete upwards in cross section, glabrous or arachnoid above (evanescent), 1-nerved above (barely visible), 1-nerved beneath, fleshy, matte; leaf lobes 3.6-5.9 × 0.8-1.2 mm, entire or 2(-3)-divided, acute to obtuse, sometimes mucronate. Capitula radiate, erect, sessile to subsessile. Involucres 12.1-16.7 × 9.8-15.7 mm, cupuliform; involucral bracts 12 to 13, 6.3-9.3 × 2.4-3.9 mm, obtuse at the apex, greenish, purple-edged. Ray florets 21 to 36; corollas 9.2-14.1 × 1.4-1.9 mm, 4 to 5-veined, subentire to 3-toothed at the apex, conspicuously surpassing the involucre, white. Disc florets 49 to 63; corollas 5.5-7.2 mm long, yellowish; style branches penicillate, purplish. Achenes 3.5-3.9 × 1-1.1 mm, cylindrical, 7 to 8-ribbed, glabrous; pappus 6.7-8.9 mm long, barbellate, whitish to partially rose-colored. Chromosome number 2 n = 104( ± 4) ( Diers 1961). Fig. 2D .

Additional iconography.

Weddell (1856: pl. 17D, sub Werneria digitata ); Ricardi and Marticorena (1966: 26, fig. 6, sub W. pseudodigitata ); Beltrán (2016: 359, fig. 3B, as photo); Gonzáles et al. (2016: 169, fig. 1H, I, sub X. pseudodigitatum , as photo).

Distribution and habitat.

Central Peru to northern Chile. Bolivia (Oruro, Potosí), Chile (Antofagasta, Arica-Parinacota, Tarapacá), Peru ( Apurímac [expected], Arequipa, Ayacucho, Cusco, Huancavelica, Junín, Lima, Moquegua, Puno). It grows in wet rocky outcrops, marsh and stream edges, and on cryoturbated soils of the puna ecoregion, between elevations of 3700-5300 m (Fig. 23 ).

Phenology.

Flowering nearly all year round.

Etymology.

The adjective digitatus -a -um refers to the shape of the leaves, which have divisions arranged like those of a bird’s foot (3-forked).

Notes.

Xenophyllum digitatum is characterized by its 3-forked leaves, where each lobe can be, in turn, 2 to 3-divided. The depth of the primary division reaches 1/3-1/2 of the total leaf length and the leaf margin usually have some cilia in the lower half. It has quite large involucre (12.1-16.7 × 9.8-15.7 mm) with 12 to 13 involucral bracts, 21 to 36 ray florets (with white corollas conspicuously surpassing the involucre), 49 to 63 disc florets, and glabrous achenes.

It is a variable species mainly concerning leaf lobe shape and leaf indumentum. Typical forms have entire leaf lobes but some specimens display 2-divided lobes (Meneses 5446, LPB; Yager 4697, LPB), or even 3-divided (Humbert 30793, USM; Hutchinson 1212, CONC, F, GH, LE, NY, UC, US, USM). The leaf lobe apex is acute to obtuse, although populations with clearly mucronate apex also exist such as those from Ausangate in Cusco (e.g., Humbert s.n. [Vargas 12143], US, CUZ). The leaf lamina is usually glabrous but specimens with evanescent arachnoid indumentum on the adaxial surface are also found. Based on this latter character, Rockhausen (1939) described the plants with indumentum as Werneria digitata var. lanata Rockh. We consider it as part of the variability encompassed by X. digitatum , and accordingly, Rockhausen’s name is treated as a heterotypic synonym.

This species has been confused with X. pseudodigitatum (Rockh.) V.A.Funk and X. rosenii . For details on their morphological differences see the comments under the respective species.

Additional specimens examined.

Bolivia. Oruro: Sajama, ladera E del río Sururia, 18°13'S, 68°54'W, 7 May 1981, M. Liberman 352 (LPB); Sajama, al sur del volcán Sajama, 18°7'S, 68°52'W, 1 May 1993, M. Sauvain 827 (LPB); Avaroa, Cruce Ventilla, Tirani, en línea recta a 13.1 km al W, Ayllu Puraca, 19°4'S, 66°19'W, 26 Feb 2016, F. Zenteno 16686 (USM); Potosí: cordillera Kari Kari, aprox. 3.3 km arriba de la laguna San Sebastián, 19°36'S, 65°41'W, 13 Feb 2019, J. Calvo & M. Zárate 7871 (BOLV); Sud Lípez, cerro Tapaquillcha, ladera S, 21°31'S, 67°53'W, 13 Apr 1980, M. Liberman 191 (LPB); Tomás Frías, aprox. 4 km saliendo por carretera Potosí-Tarija, cordillera de la ciudad de Potosí, 19°36'S, 65°41'W, 28 Feb 2006, M. Zárate 2216 (BOLV, LPB). Chile. Antofagasta: El Loa, el Tatio, 22°20'S, 68°1'W, 20 Oct 1976, M. Castillo s.n. (CONC); El Tatio, quebrada cerca del campamento de la CORFO, 22°22'S, 68°0'W, 26 Apr 1969, M. Mahu 4108 (SGO); El Loa, Ujina, 20°58'S, 68°37'W, 17 Jan 1943, E. Pisano & J. Venturelli 1724 (CONC, SGO); Arica-Parinacota: Parinacota, cerro Guane Guane, 18°10'S, 69°15'W, 20 Apr 1980, M. Arroyo, C. Villagrán & J. Moreno 2660 (CONC); Parinacota, quebrada Cataguanchuta, 18°14'S, 69°31'W, 17 Dec 1988, E. Belmonte 88668 (CONC); Portezuelo de Chapiquiña, faldeos al lado norte del campamento, 18°19'S, 69°30'W, 10 Feb 1964, C. Marticorena, O. Matthei & M. Quezada 110 (CONC); quebrada Ancochallane, 18°15'S, 69°24'W, 18 Jun 2015, A. Moreira-Muñoz 2495 (SGO); Portezuelo de Chapiquiña, 18°19'S, 69°30'W, 26 Mar 1961, M. Ricardi, C. Marticorena & O. Matthei 201 (B, CONC); Tarapacá: Iquique, Collaguasi, quebrada La Represa, 20°59'S, 68°38'W, 22 Jan 1993, S. Teillier 3011 (CONC). Peru. Arequipa: Castilla, Orcopampa, minas de Poracota, cerca a quebrada Faculla, 15°14'S, 72°33'W, 20 Apr 2011, H. Beltrán 7111 (USM [mixed with X. ciliolatum ]); Castilla, Orcopampa, minas de Poracota, cerca a quebrada Faculla, 15°14'S, 72°32'W, 20 Apr 2011, H. Beltrán 7114 (USM); Condesuyos, Salamanca, bofedal de Tintarcocha, 15°13'S, 72°30'W, 26 Mar 2012, I. Treviño 761 (HSP); Ayacucho: Huamanga, Ocollo, hacia abra Apacheta, 13°29'S, 74°28'W, 26 Jun 2010, A. Cano et al. 19873 (USM); Cusco: Anta, Mollepata, 13°24'S, 72°43'W, 12 May 2013, H. Beltrán 7672 (USM); cordillera de Vilcanota, camino al cerro Orqo Q’ocha, 13°45'S, 71°4'W, Mar 2008, C. García 86 (LPB); cordillera de Vilcanota, camino al cerro Orqo Q’ocha, 13°45'S, 71°4'W, Mar 2008, C. García 87 (LPB); Paucartambo, hacienda Churu, Jan 1926, F.L. Herrera 1033 (CONC, F, GH, MO, NY); Quispicanchi, Paucartambo, hacienda Ccapana, 13°34'S, 71°25'W, Apr 1926, F.L. Herrera 1056 (F); Quispicanchi, Paucartambo, hacienda Ccapana, 13°34'S, 71°25'W, Apr 1926, F.L. Herrera 1081 (BM, CONC, F, GH, MA, NY); cordillera del Auzangate, paso de Hualla-Hualla, 13°38'S, 71°6'W, 28 May 1958, H. Humbert et al. 30793 (USM); Quispicanchi, laguna Ampatuni [Ampatune], 13°35'S, 71°10'W, 29/30 May 1958, H. Humbert s.n. [C. Vargas 12143] (CUZ, US); cordillera de Vilcanota, cuenca de la laguna Sibinacocha, cerro Rititica, 13°45'S, 71°4'W, 5 Apr 2012, R.I. Meneses et al. 5446 (LPB); cordillera de Vilcanota, cuenca de la laguna Sibinacocha, cerro Orqo Q’ocha, 13°45'S, 71°4'W, 7 Apr 2012, R.I. Meneses et al. 5467 (LPB); Urubamba, laguna de Kellococha, proximidades de los nevados Balcunniyuc e Yllahuamán, 13°12'S, 72°15'W, 20 Aug 1988, A. Tupayachi 736 (US); cordillera de Vilcanota, Sibinacocha, 13°45'S, 71°4'W, 12 Mar 2008, K. Yager 4697 (LPB); Huancavelica: Huaytará, Pilpichaca (abra Apacheta), 13°20'S, 74°44'W, 4 Jul 2010, A. Cano, W. Mendoza & A. Delgado 19686 (USM); Huaytará, Pilpichaca (abra Apacheta), 13°20'S, 74°43'W, 4 Jul 2010, A. Cano, W. Mendoza & A. Delgado 19734 (USM); Angaraes, Ccochaccasa, 12°56'S, 74°47'W, 4 Apr 2014, A. Cano, B. Britto & N. Valencia 21926 (USM); Huaytará, alrededores de abra Apacheta, 13°18'S, 74°41'W, 3 Sep 2013, P. Gonzáles et al. 2781 (USM); Huachocolpa, alrededores de la unidad minera Caudalosa, 13°4'S, 75°0'W, 23 Mar 2015, P. Gonzáles 3559 (USM); Huachocolpa, alrededores de la unidad minera Caudalosa, 13°4'S, 75°0'W, 23 Mar 2015, P. Gonzáles 3562 (USM); nevado Ajchi, Aug 1961, O. Tovar 3423 (USM); Junín: Anticona pass, ca. 140 km E of Lima, 11°35'S, 76°11'W, 21 Dec 1978, M. Dillon & B.L. Turner 1478 (USM); Lima-La Oroya highway, cumbre at top of divide, above Morococha, 11°36'S, 76°8'W, 29 Jun 1982, A. Gentry & R. Tredwell 37301 (USM); Yauli, paso de Ticlio, carretera Lima-Oroya, 11°35'S, 76°11'W, 6 Dec 1960, E. Pallardelly 1 (USM); abra de Ticlio, 11°35'S, 76°11'W, Dec 1986, S. Rivas et al. s.n. (USM); Anticona, abajo entre Casapalca y Oroya, 11°35'S, 76°11'W, 26 Jun 1954, O. Tovar & L. Constance 9194 (USM-29378 [mixed with X. ciliolatum and X. decorum ], USM-29379, USM-34159); Yauli, Ticlio, 11°35'S, 76°11'W, 28 Jun 1999, G. Yarupaitán 1690 (US); Lima: Yauyos, Laraos (zona de Pacocha e Ipillo), 12°20'S, 75°43'W, 20 Nov 1996, H. Beltrán 2579 (USM); Huarochirí, paso de Anticona, 11°35'S, 76°11'W, 1 May 1999, H. Beltrán & E. Li 3305 (USM); Yauyos, Laraos, Viscollo, 12°25'S, 75°36'W, 12 May 2001, H. Beltrán 4193 (USM); Anticona, límite entre Lima y Junín, 11°27'S, 76°13'W, 24 Jan 2004, H. Beltrán 5863 (USM); Huarochirí, Chicla, abra Anticona (Ticlio), 11°36'S, 76°11'W, 29 Apr 2017, H. Beltrán, S. Castillo & M. Arakaki 7964 (USM); Huarochirí, Chicla, abra Anticona (Ticlio), 11°35'S, 76°11'W, 29 Apr 2017, H. Beltrán, S. Castillo & M. Arakaki 7989 (USM); límite con dpto. Junín, entre Casapalca y Ticlio, 11°35'S, 76°11'W, 1 Dec 1977, S. Castroviejo, M. Costa & E. Valdés-Bermejo 1120 (MA); puerto de Ticlio, entre Casapalca y Morococha, 11°35'S, 76°11'W, 6 Mar 1979, A. Ceballos et al. 8 (MA); Huarochirí, Ticlio, 11°35'S, 76°11'W, 5 Mar 1966, E. Cerrate, C. Acleto & J. Gómez 4289 (USM); La Oroya, Anticona, 11°35'S, 76°10'W, 25 Apr 1971, E. Cerrate et al. 4907 (USM); Ticlio, top of divide between Lima and La Oroya, 11°35'S, 76°11'W, 29 Jan 1983, A. Gentry et al. 39749 (USM); Huarochirí, San Damián, Chanape, 11°53'S, 76°15'W, 5 Jul 2013, P. Gonzáles & B. Brito 2629 (USM); Huarochirí, Ticlio, canyon of the río Rimac, on the carretera central, 11°35'S, 76°11'W, 19 Aug 1957, P.C. Hutchison 1212 (CONC, F, GH, LE, NY, UC, US [all specimens mixed with X. decorum ], USM); Anticona, 11°35'S, 76°14'W, 5 Aug 2012, E. Linares & A. Galán 3099 (USM); Anticona, 11°35'S, 76°11'W, 4 Aug 2012, E. Linares & A. Galán 3100 (USM); Ticlio, 11°35'S, 76°11'W, Feb 1974, O. Tovar 7191 (USM); Huarochirí, Ticlio, 11°35'S, 76°11'W, Nov 1975, F. Weberling 5891 (USM); Huarochirí, San Juan de Iris, bajando por la cumbre de Tres Cruces, 11°41'S, 76°31'W, 18 Aug 1993, G. Yarupaitán & J. Albán 1063 (USM); Huarochirí, San Juan de Iris, bajando de la cumbre de Tres Cruces, 11°41'S, 76°31'W, 18 Aug 1993, G. Yarupaitán & J. Albán 1067 (USM); Huarochirí, paso de Anticona, Ticlio, 11°35'S, 76°11'W, 29 Oct 1994, G. Yarupaitán 1501 (USM); Moquegua: above unpaved mining road that is high above the valley [pr. Paripiña, according to coordinates], 16°38'S, 70°1'W, 15 Mar 2014, V.A. Funk, M. Diazgranados & E. Cochachin 13169 (US, USM); near former bofedal that is now mostly dead as a result of the mining operation [pr. Paripiña, according to coordinates], 16°39'S, 70°1'W, 15 Mar 2014, V.A. Funk, M. Diazgranados & E. Cochachin 13171 (US, USM); Mariscal Nieto, Calacoa, pr. Achacalane, 16°41'S, 70°33'W, 4 Mar 2018, D. Montesinos & J. Calvo 5999 (HSP); Puno: Carabaya, Quelcaya, 13°58'S, 70°50'W, 15 Feb 2009, E. Mondragón & J. Postigo 90 (USM); San Antonio de Esquilache, 16°6'S, 70°17'W, 18 May 1937, D. Stafford 748 (BM, F, K).

Figures

Figure 2. Main habit types in Xenophyllum A, B species forming dense mats or hummocks C, D species forming clumps of somewhat distantly spaced stems A X. humile (Ecuador, Pichincha, pr. Papallacta) B X. sotarense (Colombia, Cauca, Sotara Volcano) C X. juniperinum (Chile, Antofagasta, Aucanquilcha Volcano) D X. digitatum (Bolivia, Potosi, cordillera Kari Kari). Pictures by Joel Calvo.

Figure 23. Distribution map of Xenophyllum digitatum (left hand) and X. pseudodigitatum (right hand).