Hieracium ciucasense Szeląg, 2023

Szeląg, Zbigniew, 2023, A new species in Hieracium sect. Alpina (Asteraceae) from the Eastern Carpathians in Romania, Phytotaxa 585 (4), pp. 293-297 : 293-297

Hieracium ciucasense Szeląg , sp. nov. ( Figs. 1−3 )

Type: — ROMANIA. Eastern Carpathians, Ciucaş Mts. , the “ Babele la Sfat ” rocks along a path to Ciucaş summit, shaded calcareous scree, 1800 m a.s.l., originally found on July 21, 2019, specimens from plants cultivated from seed in the author’s garden, pressed on June 5, 2021, Z. Szeląg (holotype KRAM; isotypes Herb. Hierac. Z. Szeląg) .

Paratypes: — ROMANIA. Eastern Carpathians, Ciucaş Mts., the “ Babele la Sfat ” rocks along a path to Ciucaş summit, shaded calcareous scree, 1800 m a.s.l., July 21, 2019, Z. Szeląg ( Herb. Hierac. Z. Szeląg); Ciucaş Mts. , along a tourist path from the Ciucaş shelter to Mt. Ciucaş, 1770 m a.s.l., July 21, 2019, Z. Szeląg ( Herb. Hierac. Z. Szeląg) .

Description: —Phyllopodous with overwintering brown-purple spotted rosette leaves. Stem 20–30 cm high, purplish at base, in lower and middle part with sparse pale simple hairs 1.0– 1.3 mm long and numerous stellate hairs; within synflorescence with dense stellate hairs, scattered dark-based simple hairs up to 1.5 mm long, and with dispersed blackish glandular hairs 0.3–0.5 mm long. Synflorescence branches 0–3, monocephalous, up to 6 cm long. Acladium up to 5 cm long. Rosette leaves 6–12, up to 11 cm long and up to 2 cm wide, cuneate at base, tapered to a long, purplish petiole at base, with brownish-purple spots visible before anthesis and in autumn; outer leaves obovate, rounded at apex, remotely denticulate at the base of lamina; inner leaves broadly lanceolate, acute at apex, sharply denticulate; upper surface glabrous, somewhat glaucescent; lower surface with sparse or numerous, pale simple hairs up to 1.0 mm long, without or with few stellate hairs only on the midrib; margins with numerous pale simple hairs up to 1.0 mm long and dispersed yellowish glandular hairs 0.2 mm long. Cauline leaves 1–3, rapidly reduced in size upwards; lowest leaf (if present) similar to inner rosette leaves in shape and indumentum; upper cauline leaves linear, bractlike; lower surface covered by dense pale simple hairs, scattered stellate hairs and a few glandular hairs; upper surface glabrous. Peduncles erect with dense stellate hairs, moderately numerous dark-based simple hairs up to 1.0 mm long and scattered blackish glandular hairs 0.3–0.5 mm long. Bracteoles 0–2, blackish green with numerous dark-based simple hairs up to 1 mm long, sparse blackish glandular hairs and sparse stellate hairs. Involucres 12–13 mm long, subglobose at base, with moderately dense indumentum. Involucral bracts in three rows; outer bracts shorter and squarrose; dark green, only inner bracts with pale margins, lanceolate, subulate, with numerous, black in lower half, simple hairs up to 1.3 mm long, moderately numerous stellate hairs and blackish glandular hairs 0.3–0.5 mm long. Ligules yellow, sparsely ciliate at apex. Styles almost black. Achenes black, 3.6–3.8 mm long. Pappus pale grey. Pollen in anthers very sparse. Flowering: July.

Distribution and habitat: —Endemic to the Ciucaş Mountains in the Eastern Carpathians ( Fig. 4 ). In 2019, the population of H. ciucasense comprised several dozen plants, most of them flowering. They were growing on shaded calcareous scree around the massive conglomerate outcrops, at 1800–1850 m a.s.l., as well as on the southern slope along a tourist path from the Ciucaş shelter to Mt. Ciucaş, at 1770–1800 m a.s.l.

Notes: —Hitherto, the only representative of the H. pietroszense aggregate in the Ciucaş Mountains was H. pietroszense subsp. bifidifolium Degen & Zahn in Zahn (1907: 72) described from the Rodna Mountains in the Eastern Carpathians ( Nyárády 1965). According to Nyárády (1965) it occurs also in some other mountain ranges of Romania, but according to Mráz (2003), it only grows in the Rodna Mountains and most probably is conspecific with H. pietroszense Degen and Zahn in Zahn (1907: 72). In addition, my long-term field observations have led to the conclusion that in different mountain ranges of the Carpathians, the stenoendemic taxa of the H. pietroszense aggregate have originated in situ as a result of hybridization between sexual H. alpinum , a common species in the Romanian Carpathians, and the local populations of H. bifidum s. lat. Many of these taxa are still waiting to be described, and their morphological differences are subtle and only become clearly visible when grown in the garden ( Fig. 3 ). Therefore, such a wide distribution of H. pietroszense subsp. bifidifolium as suggested by Nyárády (1965) seems to be unlikely.

Besides newly described H. ciucasense , the following species of the H. pietroszense aggregate are known in the Carpathians: H. jasiewiczii Szeląg (2019: 72) in the Bieszczady Mts. in Poland, H. deylii Mráz (2003: 311) in the Svydovets Mts. in Ukraine, and H. pietroszense and H. borsanum Mráz (2001: 329) in the Rodna Mts. in Romania ( Fig. 4 ).

Affinity: —Apart from the brownish-purple spotted rosette leaves, which differentiate Hieracium ciucasense from the other taxa of the H. pietroszense aggregate in the Carpathians, the new species differs from H. pietroszense also in its (1) narrower (up to 2 cm wide) rosette leaves, cuneate at the base and glabrous on the upper surface, (2) involucral bracts with shorter (up to 1.3 mm long) simple hairs, and (3) smaller (up to 12 mm long) involucres. Hieracium ciucasense differs from H. jasiewiczii in its (1) somewhat glaucescent leaves, and (2) much shorter simple hairs on the involucral bracts; and from H. borsanum and H. deylii in its (1) glabrous on the upper surface rosette leaves, and (2) shorter simple hairs on the involucral bracts.

Figures

FIGURE 1. Holotype of Hieracium ciucasense (KRAM).

FIGURE 2. Holotype of Hieracium ciucasense: capitulum.

FIGURE 3. Hieracium ciucasense cultivated in the garden: the young leaves and previous year’s leaves have visible brown-purple spots on April 13, 2020 (left); the same plants two weeks later (right).

FIGURE 4. Distribution of the Hieracium pietroszense aggregate in the Carpathians: 1. H. jasiewiczii; 2. H. deylii; 3. H. pietroszense and H. borsanum; 4. H. ciucasense.