**Group 1: Botanical Features**
– Asteraceae members are herbaceous plants, with some shrubs, vines, and trees.
– They are distinguishable by their unique inflorescence and shared characteristics, like joined stamen anthers.
– Identifying genera and species can be challenging.
– Roots typically develop taproots, occasionally with fibrous root systems.
– Some species have underground stems like caudices or rhizomes, which can be fleshy or woody.
– Stems are herbaceous, aerial, and branched, often with glandular hairs.
– Leaves may be alternate, opposite, or whorled, and can be simple or deeply lobed.
– Inflorescences are borne in dense flower heads called capitula, which are composite structures attracting pollinators.
– Floral structures consist of florets forming a corolla tube, with disc florets being actinomorphic and ray florets zygomorphic.
– Fruits are achene-like called cypselae, with various morphologies aiding in seed dispersal.
**Group 2: Taxonomy and Evolution**
– The original name Compositae is still valid under the International Code of Nomenclature for algae, fungi, and plants.
– The family includes over 32,000 currently accepted species.
– The crown group of Asteraceae evolved at least 85.9 million years ago.
– Heterocarpy, the ability to produce different fruit morphs, is common in Asteraceae.
– The family’s success may be attributed to the development of specialized capitula and energy storage abilities.
– Taxonomically, the family has traditionally been divided into subfamilies, with ongoing challenges in generic circumscriptions.
**Group 3: Distribution and Habitat**
– Asteraceae species have a widespread distribution, from subpolar to tropical regions in various habitats.
– Most species occur in hot desert and cold or hot semi-desert climates.
– They are found on every continent except Antarctica, with a concentration in tropical and subtropical regions.
– The largest proportion of species occur in arid and semi-arid regions of subtropical and lower temperate latitudes.
– Anemochory and epizoochory are common dispersal methods in Asteraceae.
**Group 4: Uses and Economic Importance**
– Asteraceae is economically important, providing products like cooking oils, leaf vegetables, sunflower seeds, and herbal teas.
– Several genera are of horticultural importance, used in herbal medicine and as ornamental plants.
– Commercially important plants in Asteraceae include lettuce, chicory, sunflower, and artichoke.
– Many species are grown as ornamental plants for their flowers and are used in the cut flower industry.
**Group 5: Ecology and Medicinal Properties**
– Many species are pollinated by insects, attracting beneficial insects.
– Apomictic species are present in the family.
– Some members are economically important as weeds and invasive species.
– Certain species are toxic to grazing animals.
– Asteraceae store energy in the form of inulin and produce various secondary metabolites with medicinal potential.
The family Asteraceae (/ˌæstəˈreɪsiiː, -siaɪ/), with the original name Compositae, consists of over 32,000 known species of flowering plants in over 1,900 genera within the order Asterales. Commonly referred to as the aster, daisy, composite, or sunflower family, Compositae were first described in the year 1740. The number of species in Asteraceae is rivaled only by the Orchidaceae, and which is the larger family is unclear as the quantity of extant species in each family is unknown.
| Asteraceae Temporal range: Campanian–recent
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| Twelve species of Asteraceae from the subfamilies Asteroideae, Carduoideae, and Cichorioideae | |
Scientific classification 
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| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Eudicots |
| Clade: | Asterids |
| Order: | Asterales |
| Family: | Asteraceae Bercht. & J.Presl |
| Type genus | |
| Aster | |
| Subfamilies[citation needed] | |
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| Diversity | |
| 1,911 genera | |
| Synonyms | |
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List
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Most species of Asteraceae are annual, biennial, or perennial herbaceous plants, but there are also shrubs, vines, and trees. The family has a widespread distribution, from subpolar to tropical regions, in a wide variety of habitats. Most occur in hot desert and cold or hot semi-desert climates, and they are found on every continent but Antarctica. Their primary common characteristic is flower heads, technically known as capitula, consisting of sometimes hundreds of tiny individual florets enclosed by a whorl of protective involucral bracts.
The oldest known fossils are pollen grains from the Late Cretaceous (Campanian to Maastrichtian) of Antarctica, dated to c. 76–66 million years ago (mya). It is estimated that the crown group of Asteraceae evolved at least 85.9 mya (Late Cretaceous, Santonian) with a stem node age of 88–89 mya (Late Cretaceous, Coniacian).
Asteraceae is an economically important family, providing food staples, garden plants, and herbal medicines. Species outside of their native ranges can be considered weedy or invasive.