Hieracium lachenalii subsp. zerbanum 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 : 51

5. Hieracium lachenalii subsp. zerbanum Gottschl. & S. Orsenigo , subsp. nov. ( Fig. 6 , 8e )

Type:— ITALY. Emilia-Romagna, prov. Piacenza, Zerba, Monte Lesima , 44°41’04’’N, 09°15’21’’E, 1650–1700 m, meadows along the road to the summit, 21.07.2020, G. Gottschlich 75898 & S. Orsenigo (holotype: FI!; isotypes: Hieracia Europaea Selecta No. 951, B!, FR!, H!, IBF!, LI!, M!, MSTR!, PAL!, PAV!, W!, Hb. Gottschlich-75894, Hb. Dunkel-38251, Hb. Brandstätter-33119) .

Diagnosis:—Subspecies insignis foliis caulinis conspicue angustis, minus numerosis et tantum denticulatis vel breviter dentatis dignoscenda.

Perennial, rhizome stout, horizontal to oblique. Stem erect, vertical, cylindrical, stout (Ø 2–3 mm), (45)50–60(65) cm tall, green or reddish green, brownish-purple at the base, striated, phyllopodous, with sparse 1.5–2.5 mm long, whitish, soft, simple and dentate hairs and sparse stellate hairs, without glandular hairs.

Basal leaves (1)2–3(5), with 3–5 cm long petiole, elliptical, leaf blade 6–10 × 2–3 cm, dentate to shortly dentate, upper surface grass-green, glabrous or sometimes with 1–1.5 mm long white, soft simple hairs, lower surface greyishgreen, with sparse simple hairs, along the vein simple hairs moderate, 2–2.5 mm long and with sparse stellate hairs; upper surface and margins with sparse 1 mm long white, soft, dentate simple hairs, vein of the lower surface with moderate 1.5–2 mm long simple hairs. Cauline leaves 3, the lower ones petiolate, the upper ones attenuate-sessile, leaf blade narrowly elliptical, acute, 2–6 × 0.5–2 cm, colour and indumentum similar to those of the basal leaves.

Synflorescence paniculate, branches (2)3–5(7), straight or curved, 2–5(10) cm long, each with 1–2(4) capitula, capitula (3)5–10(15); acladium 1.5–2 cm long. Peduncles with 1–2 linear bracts, 1.5–2 mm long, with moderate 0.3–0.4 mm long black glandular hairs, moderate stellate hairs, without simple hairs. Involucre campanulate, 9–10 mm long. Involucral bracts in a few series, blackish green, linear-lanceolate, 1–1.3 mm wide, acute, with moderate 0.7–1 mm long, black, glandular hairs and scattered sparse stellate hairs, without simple hairs. Corolla limb ligulate, yellow, not ciliate. Styles yellow with black papillae, margins of alveoli shortly dentate, achenes blackish brown.

Etymology:—The species epithet refers to the village Zerba east of Mount Lesima.

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

Distribution and ecology:— Hieracium lachenalii subsp. zerbanum is currently known only from the meadows above the treeline of Mount Lesima. It grows in the upper grasslands, not far from the radar tower, close to the summit, between 1650 and 1700 m of elevation.

Conservation status:—Due to its restricted range and reduced number of mature individuals (<1,000), Hieracium lachenalii subsp. zerbanum 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 this subspecies.

Remarks:—The collective species H. lachenalii Suter (1802: 145) is a complex of numerous forms. In Italy, except for the Ligurian Apennine it occurs only in a few places of the Northern Apennine. All records from the Middle and Southern Apennines, often determined as H. vulgatum Fries (1819: 128) , belong to the other species, mainly to H. grovesianum Belli (1897: 491) ( Gottschlich 2005, 2009). Hieracium lachenalii subsp. zerbanum combines the characters, which cannot be found in other taxa. Due to its isolated occurrence on Mt. Lesima, it can be regarded as a local endemic.

Figures

FIGURE 6. Hieracium lachenalii subsp. zerbanum (isotype: Hb. Gottschlich-75898).

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.