Hieracium lesimanum Gottschl. & S. Orsenigo, 2021

Gottschlich, Günter & Orsenigo, Simone, 2021, New taxa of Hieracium (Asteraceae) from Mount Lesima and adjacent regions (Northern Apennine, Italy), Phytotaxa 505 (1), pp. 39-55 : 41

1. Hieracium lesimanum Gottschl. & S. Orsenigo , spec. nov. ( Figs. 2 , 8a )

Type:— ITALY. Emilia-Romagna, prov. Piacenza, Zerba, Monte Lesima , 44°41’N, 09°15’E, 1550–1650 m, meadows along the road to the summit, 21.07.2020, G. Gottschlich & S. Orsenigo 75892 (holotype: FI!; isotypes: B!, M!, PAV!, W!, Hb. Gottschlich-75892, Hb. Dunkel) .

Diagnosis:—Ab Hieracium falcatum Arvet-Touvet (1873: 22) , H. falcatiforme Degen & Zahn in Zahn (1908: 123) et H. neyranum Arvet- Touvet (1888: 20) foliis basalibus nullis, nec non ab Hieracio orthophyllo Beck (1884: 448) numero capitulorum (15–25 contra 5–8) differt.

Perennial, rhizome stout, oblique or vertical. Stem erect, vertical, cylindrical, stout (Ø 1.5–2 mm), (65)75–85(95) cm tall, green, brownish-purple at the base, striated, aphyllopodous (rarely hypophyllopodous), with few, 1–1.5 mm long, whitish, soft, simple hairs, without stellate and glandular hairs in the lower part, nearly glabrous above.

Cauline leaves 8–10(15), 3–15 × 0.3–2 cm, the lower ones petiolate, narrowly oblong-elliptical, entire or denticulate, acute, upper surface grass-green, nearly glabrous, lower surface light green with sparse simple white hairs 1–1.5 mm long, the others gradually decreasing in size upwards, cordate or semiamplexicaul at base, indument similar to that of the lower leaves.

Synflorescence paniculate, branches (4)6–8(10), straight or curved, 1.5–10 cm long, each with (1)2–5(7) capitula (often partly abortive); capitula (10)15–25(35); acladium 0.5–1.5 cm long. Peduncles with 1–2 linear, green or dark green bracts, 1–2 mm long, with sparse 1 mm long simple hairs, white but with a dark base, sparse black or blackyellowish, 0.2 mm long glandular hairs, and subdense stellate hairs. Involucre narrowly campanulate, 9–10 mm long. Involucral bracts in a few series, blackish green, linear-lanceolate, 0.6–1 mm wide, acute, with moderate, 1 mm long simple hairs, upper half white, base black, sparse 0.2mm long black to black-yellowish glandular hairs, and sparse stellate hairs along the margin. Corolla limb ligulate, yellow, indistinctly ciliate. Styles blackish. Margins of alveoli with broad teeth. Achenes 3–4 mm long, brown.

Etymology:—The species epithet refers to the name of the mountain where the plant grows.

Phenology: —Flowering late July to August. Fruiting in August.

Distribution and ecology:— Hieracium lesimanum is known only from the grasslands above the treeline of Mount Lesima, where it was found only in a restricted area on the northern slope at elevations between 1550 and 1650 m.

Conservation status:—Due to its restricted range and reduced number of mature individuals (<1,000), H. lesimanum could preliminary be listed as “Vulnerable” (VU) under criterion D1, according to the IUCN criteria (2019). Despite at the moment there are no ongoing threats, changes in grazing pressure could have a negative impact on the population of H. lesimanum .

Remarks:—In its habit H. lesimanum resembles some other Hieracium species , which occur in different parts of the Alps and the Apennine. The diagnostic differences and distribution are given in Table 1. Hieracium lesimanum should be classified in H. sect. Prenanthoidea Koch (1844: 527).

Figures

FIGURE 2. Hieracium lesimanum (isotype, Hb. Gottschlich-75892).

FIGURE 8. Single capitula of a: H. lesimanum, b: H. scopolii, c: H. scopolioides, d: H. umbrophilum, e: H. lachenalii subsp. zerbanum, f: H. prenanthoides subsp. penicense.