Leucheria arancioi Jara-Arancio, Ratto & Adr. Bartoli, 2019

Leucheria arancioi Jara-Arancio, Ratto & Adr. Bartoli View in CoL , nom. nov.

Leucheria diemii Cabrera var. purpurea Ratto, M. Bello & Adr. Bartoli (2014: 92) .

Type:— ARGENTINA. Prov. Santa Cruz: Dpto. Río Chico, Estancia La Siberia , 1237 m, 14.01.2013, Ratto et al. 352 (holotype BAA).

Description

Perennial herb about 10 cm tall, rhizomatous, acaulescent. Leaves 30–50 × 4–12 mm, petiolate, lamina simple, spatulate, entire or irregularly toothed, apex subacute or obtuse, rounded in some leaves, tomentose on both sides, forming a dense rosette with remains of dry leaves and petioles. Capitulum homogamous, discoid, solitary, peduncles 30–60 mm long, tomentose, with a linear-elliptic bract 10–15 × 1–2 mm. Involucrum flared, phyllaries in two subequal series, imbricate, elliptic, tomentose, 8–10 × 1–2 mm. Flowers 40–42 per capitulum, isomorphic, perfect, corollas purple, 8– 10 mm long, bilabiate, glabrous, exterior lip 3-toothed, 2.9 × 2.2 mm, interior entire or slightly bifid, 2.25 × 0.92 mm. Anthers notably sagittate, 0.8–1.2 mm long, apical connective appendix 1–1.2 mm long, lanceolate, acute, theca ending in long tails, 1–1.2 mm long, glabrous. Styles 5–6 mm long, bifid, branches 0.8–1mm long, with stigmatic papillae on internal surface, truncated and with a small corona of pollen-collecting hairs on apices, stylopodium truncated at style base. Cypselae 2–3 mm long, elliptic or elliptical-obovoid, surface tuberculate due to prominent epidermal cells, papillose-pubescent, carpopodium basal. Pappus white, formed by a series of bristles 4–6 mm long, plumose, united at base in a ring ( Fig. 4 View FIGURE 4 ).

Etymology.— Leucheria arancioi is named in honor of Constancio Arancio Cacace, Italian nature lover.

Specimens examined.—Only known from a single specimen, Ratto et al. 352 (BAA).

Phenology.— Leucheria arancioi was collected in flower in January.

Distribution.—Province of Santa Cruz, Department Río Chico, in the Patagonian phytogeographic province of Argentina. Rocky soils in mountains at 1250 m. Grows with other taxa such as Festuca pallescens (St.-Yves) Parodi, Hypochaeris incana (Hook. & Arn.) Macloskie var. incana , Perezia recurvata (Vahl) Less. and Senecio poeppigii Hook. & Arn. var. discoideus Cabrera.

Conservation status.—According to the criteria of IUCN (2001), Leucheria arancioi should be assessed as critically endangered, judging from its reduced spatial distribution and low number of individuals.