Hieracium besseri Szeląg, 2024

Szeląg, Zbigniew, 2024, Two new species in Hieracium sect. Alpestria (Asteraceae) from Mt. Babia Góra, Western Carpathians, Poland, Phytotaxa 645 (3), pp. 278-285 : 281-284

Hieracium besseri Szeląg , sp. nov. ( Figs. 2 , 4–5 )

Type: ― POLAND. Western Carpathians, Mt. Babia Góra massif, glacial niche in lowest part of the Kamienna Dolinka valley , grassland on sandstone rocks, 1550 m a.s.l., 27 July 2021, Z. Szeląg (holotype KRAM; isotypes Herb. Hierac. Z. Szeląg) .

Paratypes: ― POLAND. Western Carpathians, Mt. Babia Góra massif, upper part of the Kamienna Dolinka valley , NE slope of the Kościółek Zachodni ridge, rocky grassland below the steep sandstone rocks with Saxifrago-Festucetum versicoloris community, 1590 m a.s.l., 27 July 2021, Z. Szeląg (Herb. Hierac. Z. Szeląg) ; Mt. Babia Góra massif, glacial niche in lowest part of the Kamienna Dolinka valley , grassland on sandstone rocks, 1550 m a.s.l., originally found on 27 July 2021, specimens from plants transferred from the type locality to the author’s garden, pressed on 31 May 2023, Z. Szeląg (Herb. Hierac. Z. Szeląg) .

Description: ―Phyllopodous. Stem 35–40 cm high, green, in lower half with moderately numerous, pale, 2–3 mm long simple hairs, and with single stellate hairs; in upper half with sparse, pale, dark-based, 1–2 mm long simple hairs, numerous to subdense stellate hairs, and with scattered pale microglands. Rosette leaves 4–6, glaucescent, outer leaves (withering at anthesis) smaller and more rounded at apex; inner leaves up to 10 cm long and up to 2.5 cm wide, cuneate at base, gradually tapered to a long, winged petiole; lamina lanceolate, acute at apex, denticulate and sharply dentate, on both surfaces with sparse, 0.7–1.2 mm long, pale simple hairs, on margins and along midrib with numerous, simple hairs up to 2 mm long, without or with a few stellate hairs. Cauline leaves 3–4, gradually reduced in size upwards, on the upper surface glaucescent, on the lower surface light green. Lowest cauline leaf in shape, size and indumentum similar to rosette leaves; other cauline leaves sessile to semi-amplexicaul, lanceolate and acuminate at apex, sharply denticulate to dentate at the base of lamina, on the upper surface with very sparse (almost glabrous), pale simple hairs up to 0.5 mm long, on the lower surface with sparse, pale simple hairs up to 0.7 mm long, and very few stellate hairs (upper cauline leaf on margins and along midrib also with scattered microglands and sparse stellate hairs). Synflorescence compact on the top of stem. Synflorescence branches 3–4, up to 3 cm long, mostly monocephalous. Acladium 1.5–2 cm long. Peduncles erect, with dense stellate hairs, numerous dark-based simple hairs up to 1.2 mm long, and with sparse blackish glandular hairs 0.3–0.5 mm long. Bracteoles 2–4, grey-green with scattered stellate hairs, and dark-based simple hairs. Involucres 11–13 mm long, subglobose at base, with moderately dense indumentum. Involucral bracts in three rows, lanceolate, acute at apex, up to 1.3 mm wide at base, dark green, inner bracts with pale green margins, with numerous, blackish, up to 1.7 mm long simple hairs, sparse, blackish glandular hairs 0.3–0.5 mm long, mixed with yellow microglands, and scattered stellate hairs along margins. Ligules warm-yellow, without cilia at apex. Styles dirty-yellow with dense back microtrichomes. Achenes black, 3.8–4.3 mm long. Pappus pale-grey. Pollen in anthers very few, irregular. Flowering: end of July.

Affinity: ― Hieracium besseri is a sister species of H. engleri ( Uechtritz 1871: 293) from the Sudetes, from which differs in somewhat taller stem, more dentate leaves, and more acute rosette leaves. The morphological dissimilarities between the species become clearly visible when they are cultivated in the garden and they differ especially in the shape and number of stem leaves (up to 7 in H. besseri and up to 4 in H. engleri ), and the number of capitula ( Fig. 6 ). The keyed differences between H. besseri and H. engleri are as follows:

1. Stem in lower half with moderately numerous simple hairs 2.0–3.0 mm long and solitary stellate hairs; leaves denticulate to dentate; achenes black, 3.8–4.3 mm long............................................................................................................................ H. besseri

2. Stem in lower half with dense simple hairs 3.0–4.5 mm long and numerous stellate hairs; leaves weakly denticulate or almost entire; achenes brown-black, 3.0–3.3 mm long................................................................................................................... H. engleri

Both species are tetraploid ( Musiał & Szeląg 2023; Grabowska-Joachimiak & Szeląg, unpubl.) and belong to the H. carpathicum agg. which includes taxa morphologically intermediate between H. prenanthoides s.lat. and H. caesium s.lat. A large number of hybridogenous taxa in the Sudetes and Western Carpathians originated with the involvement of H. prenanthoides s.lat. ( Zahn 1938; Chrtek 2004) indicating that at one time the sexual populations of H. prenanthoides s.lat. must have occurred here as well. As the diploid population of H. prenanthoides s.lat. is currently known only from the Southwestern Alps (Favarge 1969; Fehrer et al. 2009), both H. besseri and H. engleri must be considered relict species.

Notes: ―Compared to the specimens from Mt. Nosal in the Tatra Mts., which were issued as H. carpathicum Besser (1809: 154) in the exsiccates by E. Wołoszczak (Flora polonica exsiccata No. 963) and cited by Zahn (1938: 375), H. besseri and H. engleri are characterized by having the compact synflorescence on the top of the stem with short, erect peduncles, and significantly shorter stems.

According to Zahn (1938), H. carpathicum is wider distributed in the Western Carpathians and, besides the Tatra Mts., it occurs also in the Nízke Tatry Mts. and Veľká Fatra Mts. In my opinion, however, it seems unlikely that plants from the Western Carpathians are conspecific with H. carpathicum which was described from specimens collected in the Eastern Carpathians ( Besser 1809). Undoubtedly, the H. carpathicum agg. in the Western Carpathians requires further research.

Distribution and habitat: —Endemic to the Babia Góra massif in the Western Carpathians, known only from the Polish side of the mountains ( Fig. 1 ). In 2023, the population of H. besseri comprised not more than 20 plants, growing in two clusters in the Kamienna Dolinka valley, in subalpine grasslands and in grassy places amongst loose bushes of Pinus mugo on sandstone bedrock.

Etymology: —The species is named in honour of Willibald Swibert Joseph Gottlieb von Besser, born on 7 July 1784 in Innsbruck, Austria. In 1798, Besser settled in Poland; initially he lived in Lwów (now Lviv in Ukraine) where he graduated from high school, then, from 1805, in Cracow, where he completed the medical studies. He was fluent in Polish. In 1821–1831, Besser was a professor of natural history at the Polish Volhynian high school in Krzemieniec (now Kremenets in Ukraine). In 1834–1838, he was a professor of botany at the University of Kiev. Besser died on 11 October 1842 and was buried in Krzemieniec.

Willibald Besser, Tyrolean by birth, Polish by choice, was well-known and valued expert of the flora of Eastern Europe, especially of the Bessarabia, Podolia and Volhynia regions ( Besser 1822, 1828, 1832). He described numerous plant species, including Hieracium carpathicum . Besser was the first botanist to visit Mt. Babia Góra, and the results of this trip he included in his monumental flora of Galicia ( Besser 1809), the historical region comprising south-eastern Poland and western Ukraine.

Figures

FIGURE 1. Distribution of Hieracium babiogorense (yellow dots) and H. besseri (red dots) on Mt. Babia Góra.

FIGURE 2. Hieracium babiogorense (left) and H. besseri (right) in the type localities.

FIGURE 4. Involucres of: A. Hieracium babiogorense; B. H. besseri (from holotypes).

FIGURE 5. Holotype of Hieracium besseri (KRAM).

FIGURE 6. Hieracium besseri (left) and H. engleri (right) specimens from plants cultivated in the author’s garden, pressed on 31 May 2023.