Erigeron acris L., Sp. Pl. 2: 863 (1753).

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

5. Erigeron acris L., Sp. Pl. 2: 863 (1753).

Type.

Probably southern Sweden. Herb. Linnaeus 994.16 (lectotype LINN, designated by Huber (1993: 44)).

Description.

Stems 25-40 cm tall, branched in the upper half, green or slightly to rather intensely purple-coloured, evenly covered by abundant hairs 1-1.3(1.5) mm long. Cauline leaves 5-10 under the synflorescence, spaced, gradually decreasing towards the stem top, completely covered by numerous hairs 0.5-1 mm long on both sides. Synflorescence with long branches carrying solitary to 2-3 capitula, nearly corymbose at the top, with numerous hairs 0.4-0.7(1) mm long. Phyllaries 6-7.5 mm long, green or purple-coloured on the tips, completely covered by hairs up to 0.7-1 mm long. Ray flowers pale-pink. Pappus greyish-white.

Flowers in July to August, fruits in August.

Distribution in Murmansk Region.

Kandalaksha Town, Nivsky Village, Kandalaksha and Apatity industrial areas, Apatity Town, Pasvik, Tetrino Village (Fig. 8A ).

Global distribution.

Boreal, Hemiboreal and Temperate zones of Europe and Siberia. Nomenclatural note. The lectotype specimen at LINN was not labelled but most likely was collected by C. Linnaeus himself in Uppsala, Sweden. This specimen is a very typical representative of the species, being a greenish plant with abundant long hairs.

Taxonomic note.

This species is characteristic for its overall green colour of stems, leaves and phyllaries, with a red tint being present mostly at the stem base and on the tips of the phyllaries. The plant habit is the same as in E. politus and E. rigidus , with rather few sparse leaves on the stem. Another typical feature of this species is a long and dense pubescence, covering all parts of the plant (stems, leaves and phyllaries).

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.