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Distribution: Asteraceae is the family of flowering plants, with an estimated 1600+
genera and 24,000 species (plus many more apomictic microspecies) found worldwide
(except Antarctica), and growing in most habitats. In Australia about 300 genera and
1417 species, the native taxa mainly in subfamilies Asteroideae (Tribes Astereae and
Gnaphalieae). Asteraceae is the second most speciose family in Australia, exceeded
only by the Myrtaceae (c. 89 genera and c. 1858 species) and rivalled only by the
pea-flowered legumes (c. 140/1402) and Poaceae (c. 230/1300)
Description: This family are a group of annual or perennial herbs, subshrubs, shrubs
or rarely small trees or lianes, usually terrestrial, rarely facultatively aquatic.
For more details regarding the description of species within this family please see:
https://profiles.ala.org.au/opus/foa/profile/Asteraceae
Pollen Morphology: The shape of the pollen in this family is highly variable and can
be separated into two grain types. Type 1 grains are circular to clover shaped and
often appear as a spikey ball. These pollen grains also have three pores and furrows
(tricolporate), however they may be difficult to see. Type 2 grains have flat panels
in a snow-flake like shape and have window-like apertures. The surface of these pollens
are also spikey. The size of the pollen in both groups are variable with most taxa
being 20-25um in diameter but some are seen to be smaller (15um).
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