The largest family of flowering plants , the Compositae (Asteraceae), comprising about 1,100 genera and more than 20,000 species and characterized by many small flowers arranged in a head looking like a single flower and subtended by an involucre of bracts. A head may consist of both ray flowers and disk flowers, as in the sunflower, of disk flowers only, as in the burdock, or of ray flowers only, as in the dandelion.
The Heliantheae are a tribe of closely related genera of the sunflower family that can be readily recognized due to the association of a receptacular bract or chaff scale with each disk floret in the head . The heads usually include bisexual , actinomorphic disk florets with tubular corollas that have 4 or 5 distal lobes and also peripheral zygomorphic female or sometimes sterile florets with strap-shaped corollas that have 3 or fewer distal teeth. However, the ray flowers are sometimes absent and the heads are then discoid , containing only bisexual florets with tubular corollas. The pappus is absent or more commonly ranges from scales to stiff bristles . -- Gerald Carr.
- Whittaker & Margulis,1978
- Haeckel, 1866
- Cavalier-Smith, 1981
- Sinnott, 1935 ex Cavalier-Smith, 1998
- Vascular Plants
- Brongniart, 1843
- Takhtajan, 1967
- Superorder: Campanulanae () - Takhtajan Ex Reveal, 1992
- Subclass: Asteridae () - Takhtajan, 1967
- Class: Magnoliopsida () - Brongniart, 1843 - Dicotyledons
- Subphylum: Euphyllophytina ()
- Phylum: Tracheophyta () - Sinnott, 1935 ex Cavalier-Smith, 1998 - Vascular Plants
- Subkingdom: Viridaeplantae () - Cavalier-Smith, 1981
- Kingdom: Plantae () - Haeckel, 1866 - Plants
Ageratum angustifolium Spreng. • Bahia angustifolia< /i> (Spreng.) Dc. • Trichophyllum angustifolium (Spreng.) Less.
Members of the genus Calea
ZipcodeZoo has pages for 2 species, subspecies, varieties, forms, and cultivars in this genus:
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