Aster

Perennial, rarely annual, herbs. Leaves alternate, sessile, entire, toothed or rarely incised, often nerves conspicuously raised, hairy or glabrous and sometimes glandular. Capitula radiate, large or medium-sized, occasionally small, solitary or in panicles or corymbs, pedunculate. Involucre campanulate or subhemispherical; bracts imbricate, in 3 or 4(5) rows. Receptacle flat or convex, epaleate. Rayflorets female, fertile or rarely sterile; staminodes sometimes present; corolla blue, violet or white, in 1 or 2 rows, tubular below, mostly glandular-hairy, often hairy as well, produced into a strap-shaped, 3-toothed lamina in upper part. Discflorets bisexual, fertile or rarely inner ones functionally male; corolla yellow, rarely purplish, tubular, expanded above, 5-toothed, always glandular-hairy. Anthers ecalcarate and ecaudate; apical appendage ovate-lanceolate, flat. Style branches narrowly oblong; apex triangular, with conspicuous sweeping hairs outside. Cypselas elliptic to obovate, compressed, bright to dark brown to blackish, usually with thickened margins, hairy and with multicellular glands. Pappus in 2 rows, inner row of bristles, outer of short narrow scales or bristles or in 1 row, of bristles only. x = 8, 9 (5, 7) (aneuploids, high polyploidy, B-chromosomes).