Carlina is a genus of about 28–34 species of flowering plants in the family Asteraceae (order Asterales), commonly known as carline thistles. The genus ranges from Madeira and the Canary Islands across Europe and northern Africa eastward to Siberia and northwestern China.
Carline thistles closely resemble true thistles of the genus Cirsium and belong to the same tribe, Cardueae (subtribe Carlininae). The genus is most closely related to Atractylis, and together they form a sister group to Atractylodes. Five subgenera are recognised: Carlina, Carlowizia, Heracantha, Lyrolepis, and Mitina.
Although most species are biennial herbs, the genus also includes annuals, perennials, shrubs, and dwarf trees, with the largest individuals reaching around 80 centimetres in height. Stems may be upright and branching or unbranched; the entire plant is spiny. Leaves have toothed or lobed blades with spiny margins and are sometimes covered in woolly hairs. Flower heads are solitary or arranged in inflorescences, hemispherical to bell-shaped in form, and surrounded by several layers of spiny phyllaries — the outermost of which can be long and leaf-like. Each head bears tubular to funnel-shaped disc florets in shades of yellow or red. The fruit is a hairy cypsela topped with a plumelike pappus composed of tufts of bristles.
Carlina was described by Carl Linnaeus and published in Species Plantarum (1753). The name honours Charlemagne (748–814): legend holds that an angel instructed the emperor to fire an arrow, and the plant where it landed — a Carlina acaulis — would cure the bubonic plague.
Several species have a long history of use in European herbal medicine. The root of Carlina acaulis, known as Carlinae radix, is used as a diuretic and a treatment for skin conditions, catarrh, and toothache. The essential oils of C. acaulis and C. acanthifolia are rich in carlina oxide, an acetylene derivative with documented antimicrobial properties. The immature flowerhead of C. acaulis is also eaten as a vegetable, prepared in the manner of an artichoke.
Etymology
The genus name Carlina honours the Frankish emperor Charlemagne (748–814). According to legend, an angel instructed Charlemagne to shoot an arrow, and the plant in which it landed — identified as Carlina acaulis — was revealed as a cure for the bubonic plague.
Distribution
Carlina ranges from Madeira and the Canary Islands through Europe and northern Africa, extending east across central Asia to Siberia and northwestern China.
Cultural Uses
The root of Carlina acaulis, sold as Carlinae radix, has long been used in European traditional medicine as a diuretic and a remedy for skin lesions, catarrh, and toothache; commercial supplies are frequently adulterated with the closely related C. acanthifolia. Both species produce an essential oil dominated by carlina oxide, an acetylene derivative with antimicrobial properties. The young, immature flowerhead of C. acaulis is also consumed as a vegetable, prepared like an artichoke.
Taxonomy Notes
Carlina belongs to the tribe Cardueae (subtribe Carlininae) of the family Asteraceae. It is most closely related to Atractylis, together forming a sister group to Atractylodes. The genus is divided into five subgenera: Carlina, Carlowizia, Heracantha, Lyrolepis, and Mitina. It was first formally described by Linnaeus in Species Plantarum (1753).
