Taxonomic revision of the Andean genus Xenophyllum (Compositae, Senecioneae) Author Calvo, Joel Instituto de Geografia, Facultad de Ciencias del Mar y Geografia, Pontificia Universidad Catolica de Valparaiso, Avenida Brasil 2241, 2362807 Valparaiso, Chile https://orcid.org/0000-0003-2340-7666 calvocasas@gmail.com Author Moreira-Munoz, Andres Instituto de Geografia, Facultad de Ciencias del Mar y Geografia, Pontificia Universidad Catolica de Valparaiso, Avenida Brasil 2241, 2362807 Valparaiso, Chile https://orcid.org/0000-0002-9136-1391 text PhytoKeys 2020 158 1 106 http://dx.doi.org/10.3897/phytokeys.158.50848 journal article http://dx.doi.org/10.3897/phytokeys.158.50848 1314-2003-158-1 8480BB61E8B2553ABA8D418072EC52B6 Xenophyllum V.A.Funk, Novon 7(3): 235. 1997. Werneria subg. Euwerneria Rockh., Bot. Jahrb. Syst. 70: 285. 1939, pro parte , nom. inval. ( Turland et al. 2018 , ICN Art. 21.3, 22.2, and 38.1). Werneria sect. Digitifoliae Rockh., Bot. Jahrb. Syst. 70: 276, 285. 1939, syn. nov. Type: Werneria digitata Wedd. [≡ Xenophyllum digitatum (Wedd.) V.A.Funk] ( Turland et al. 2018 , ICN Art. 10.8). Werneria sect. Aciculares Rockh., Bot. Jahrb. Syst. 70: 277, 291. 1939, syn. nov. Type: Werneria humilis Kunth [≡ Xenophyllum humile (Kunth) V.A.Funk], designated here. Type. Xenophyllum dactylophyllum (Sch.Bip.) V.A.Funk. Description. Suffruticose plants, forming mats, hummocks, or clumps of erect stems. Rhizomes 4-10 x 0.1-1 cm, horizontal to oblique, glabrous; rhizome-like stems (when present) up to 35 cm long covered with matted lanate, arachnoid, or pilose indumentum and old leaves or leaf base remnants, rather erect, simple or branched from the base. Stems 1-20(-60) cm long, simple or branched, glabrous, sparsely pilose, arachnoid, or lanate. Leaves alternate, simple, subimbricate, imbricate, or stellate-imbricate (rarely somewhat distantly arranged), extending into a sheath-like base that is glabrous or bears arachnoid or long silky trichomes (abruptly narrowed at the base in one species); leaf laminas 2.5-27.6 x 0.5-6.7 mm, linear, triangular, or spatulate, aristate, acute, obtuse, notched, forked, or finger-like at the apex, entire, denticulate, shortly ciliate, or scabrous-ciliate at the margin, flat to terete, sometimes slightly curved forwards in cross section, glabrous (rarely floccose-lanate), 1-nerved above (sometimes barely visible or unconspicuous), 1-nerved beneath (sometimes barely visible or unconspicuous), usually fleshy, matte or shiny (sometimes papillose). Capitula radiate (disciform in one species), solitary, terminal, erect (rarely somewhat nodding), sessile to subsessile (rarely shortly pedunculate). Involucres 3.3-19.7 x 2.7-15.8 mm, cupuliform or narrowly cupuliform, with bracts fused at the base, glabrous; involucral bracts 8 to 21, 1.1-14.9 x 0.7-3.9 mm, linear-oblong to subulate, acute to obtuse at the apex, greenish to dark-purplish; supplementary bracts absent; receptacle epaleaceous, rather plane, smooth or seldom alveolate. Ray florets 8 to 39, pistillate, fertile; corollas 3.6-19.7 x 0.4-3.4 mm, 2 to 7-veined (sometimes unconspicuous), subentire to 3-toothed at the apex, surpassing or not the involucre, white, yellow, or pink (disciform species with peripheral florets having corollas reduced to a vestigial tube or without corolla). Disc florets 7 to 95, hermaphroditic; corollas 3.1-10.6 mm long, 5-lobed, yellow, whitish, creamy, or purplish; filament collars balusterform; anther bases obtuse or auriculate; anther appendages 2-4-times longer than wide; style branches truncate with a crown of sweeping trichomes or penicillate, yellowish to purplish. Achenes 1.6-5.4 x 0.4-1.3 mm, cylindrical, 6 to 9-ribbed, glabrous or white-villous (with scattered arachnoid trichomes in one species); pappus capillary, 1 to 2-seriate, composed of bristles 2.1-19 mm long, barbellate, whitish to partially rose- or purple-colored. Chromosome number 2 n = 104-108( +/- 4) ( Diers 1961 ). Distribution and habitat. Colombia, Ecuador, Peru, Bolivia, northern Chile, and northwestern Argentina. The Xenophyllum species thrive in the paramo and puna ecoregions, between elevations of (2600-)3000-5500 m (Fig. 4 ). Etymology. The generic name Xenophyllum means strange leaves ( "xenos" : strange, alien, foreign; "phyll-" : relating to leaves). Figure 4. Distribution map of genus Xenophyllum .