Erigeron uralensis Less. in Linnaea 9: 186 (1834)

Sennikov, Alexander N. & Kozhin, Mikhail N., 2023, Taxonomic revision of the Erigeron acris group (Asteraceae) in Murmansk Region, Russia, reveals a complex pattern of native and alien taxa, PhytoKeys 235, pp. 83-128 : 83

7. Erigeron uralensis Less. in Linnaea 9: 186 (1834)

Fig. 11

Erigeron acris microcephalus - Erigeron acris var. microcephalus Ledeb., Fl. Ross. 2(2,6): 489 (1845).

Type.

Russia. Chelyabinsk Region: “Zlatoust”, 07.1832, C.F. Lessing (lectotype LE 01043675, designated here; isolectotype LE 01043674) .

Description.

Stems 30-50 cm tall, branched in the upper third, intensely to slightly purple-coloured, sparsely covered by numerous hairs 0.5-0.8 mm long. Cauline leaves 8-12 under the synflorescence, sparse or slightly congested, noticeably reduced towards the stem top, very sparsely covered by numerous hairs 0.3-0.5 mm long on both sides (nearly glabrous in the middle part). Synflorescence with rather short branches carrying few to several capitula, racemose in shape, with rather sparse hairs 0.3-0.4 mm long. Phyllaries 5.5-6 mm long, slightly or moderately purple-coloured, outer and middle ones sparsely covered by hairs up to 0.5-1 mm long, innermost ones with solitary hairs. Ray flowers pink. Pappus greyish-white.

Flowers in July to August, fruits in August.

Distribution in Murmansk Region.

Kandalaksha and Apatity industrial areas (Fig. 8C ).

Global distribution.

Boreal and Hemiboreal zones of Fennoscandia and Eastern Europe, Ural Mts.

Nomenclatural note.

The species was described on the basis of a single herbarium collection from Zlatoust Town, Chelyabinsk Region, Russia ( Lessing 1834). Ledebour (1845) cited a specimen of the original collection at the Berlin Botanical Garden, which is no longer extant. Two other specimens are preserved at the Komarov Botanical Institute in Saint-Petersburg, of which one is selected here as lectotype.

Taxonomic note.

Tzvelev (1994) recognised a single species with numerous capitula on short branches in the Russian North, which he named E. uralensis and considered to include a few other previously described species. Among these synonyms, E. decoloratus H.Lindb. and E. elongatiformis Novopokr. ex Serg. were apparently added in error because they belong to the group with corymbose synflorescences (few larger heads on longer branches), whereas E. brachycephalus shares all essential characters with the type collection of E. uralensis (paniculate synflorescence with numerous heads on shorter branches, sparse pubescence on involucres and synflorescence branches). This species is seemingly distributed from Eastern Finland ( Mäkelä 1980) to the Ural Mountains ( Lessing 1834) and Siberia ( Tzvelev 1994). Although the original material of E. brachycephalus largely includes specimens of E. uralensis , its designated lectotype ( Väre 2012) differs in the density of pubescence and should be referred to another taxon. These species names are therefore not synonyms.

Figures

Figure 8. Distribution of the Erigeron acris group in Murmansk Region, Russia A E. acris L. B E. droebachiensis O. F. Muell. C E. uralensis Less. D E. brachycephalus H. Lindb. Origin and residence status: yellow - pre-industrial alien; red - industrial alien. Maps were created using ArcGIS software by Esri. ArcGIS is the intellectual property of Esri and is used herein under license. Copyright Esri. All rights reserved.

Figure 11. Lectotype of Erigeron uralensis Less. (LE 01043675). Courtesy of the Komarov Botanical Institute, Russian Academy of Sciences.