The World Flora Online

Herbes'vivaces; souche principale pivotante, forte; tiges 1 ou plusieurs, ne dépassant pas ou guère le niveau du sol.'Feuilles'alternes, en rosette basilaire, simples, entières, dentées ou diversement découpées.'Capitules'solitaires au sommet de scapes naissant de la rosette foliaire; bractées involucrales en deux cercles, les externes plus courtes et généralement plus larges et à bords souvent plus pâles, les internes dressées et ± linéaires; réceptacle ± plan, dépourvu de paillettes.'Fleurs'à ligule généralement jaune, souvent avec une ligne foncée sur la face dorsale; style à branches grêles, obtuses au sommet.'Akènes à corps fusiforme à obovoïde, souvent finement épineux dans le haut, ordinairement prolongé par un bec grêle situé au sommet d'un cône ± différencié; pappus composé de nombreux cercles de soies simples, rugueuses, ordinairement blanches.\n\t\t\t\tGenre de la zone tempérée de l'hémisphère nord et de l'Amérique du Sud tempérée; divers taxons sont naturalisés en dehors de cette aire. Taxons très nombreux, pour la plupart décrits au rang spécifique; environ 1200 taxons en Europe, certains diploïdes et se reproduisant sexuellement, la plupart polyploïdes, parfois aneuploïdes, et apomictiques facultatifs ou obligés. Pour la Flore : 1 seule espèce (au sens large), introduite.

Pappus many-seriate consisting of numerous slender, unequal setae. Style branches long slender, sweeping hairs long. Achenes fusiform-oblanceolate, many-ribbed, narrowed and shortly conical above before tapering ± abruptly into a slender stalk-like beak (rostrum), beaks rarely absent, the ribs antrorsely muricate or echinate above. Corollas yellow (white), ligulate. Anthers sagittate at the base with shortly setaceous-acuminate auricles. Involucres oblong-campanulate; phyllaries 2-seriate, the inner series erect, the outer series shorter and spreading or recurved. Receptacle ± flat, epaleate, pitted. Leaves radical, rosulate, entire, sinuate-dentate or runcinate. Perennial scapigerous herbs with simple or branched taproots. Scapes 1-many, simple, hollow; capitula large solitary terminal. Style branches long slender, sweeping hairs long. Achenes fusiform-oblanceolate, many-ribbed, narrowed and shortly conical above before tapering ± abruptly into a slender stalk-like beak (rostrum), beaks rarely absent, the ribs antrorsely muricate or echinate above. Corollas yellow (white), ligulate. Anthers sagittate at the base with shortly setaceous-acuminate auricles. Involucres oblong-campanulate; phyllaries 2-seriate, the inner series erect, the outer series shorter and spreading or recurved. Receptacle ± flat, epaleate, pitted. Leaves radical, rosulate, entire, sinuate-dentate or runcinate. Perennial scapigerous herbs with simple or branched taproots. Scapes 1-many, simple, hollow; capitula large solitary terminal.

Fls all ligulate and perfect, yellow, mostly numerous; invol bracts biseriate, the outer usually shorter than the inner and often reflexed; achenes columnar or thickly fusiform, terete or 4–5-angled, longitudinally sulcate or ribbed, ordinarily muricate or tuberculate at least above, commonly topped by a smooth, conic or pyramidal cusp that tapers to a slender beak, or rarely beakless; pappus of numerous white capillary bristles; taprooted, lactiferous, perennial, scapose herbs, the lvs all basal and rosulate, entire to pinnatifid or subbipinnatifid. 60, mostly N. Temp. Spp. confluent through polyploidy and apomixis. Taxonomy and nomenclature in utter confusion. We here define spp. broadly and follow traditional nomenclature.

Corolla yellow, rarely whitish Achenes fusiform, with a long beak; pappus of barbellate bristles. Leaves usually pinnatilobed Capitula with phyllaries in two unequal rows Perennial herbs with a rosette of leaves and a solitary capitulum on a leafless, hollow scape Achenes fusiform, with a long beak; pappus of barbellate bristles. Leaves usually pinnatilobed Capitula with phyllaries in two unequal rows Perennial herbs with a rosette of leaves and a solitary capitulum on a leafless, hollow scape