what is astraeus hygrometricus?
A species of fungus
Astraeus hygrometricus
Astraeus hygrometricus, commonly known as the hygroscopic earthstar, the barometer earthstar, or the false earthstar, is a species of fungus in the family Diplocystaceae.
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Astraeus hygrometricus [SEP] Introduction
Astraeus hygrometricus, commonly known as the hygroscopic earthstar, the barometer earthstar, or the false earthstar, is a species of fungus in the family Diplocystaceae. Young specimens resemble a puffball when unopened. In maturity, the mushroom displays the characteristic earthstar shape that is a result of the outer layer of fruit body tissue splitting open in a star-like manner. The false earthstar is an ectomycorrhizal species that grows in association with various trees, especially in sandy soils. "A. hygrometricus" was previously thought to have a cosmopolitan distribution, though it is now thought to be restricted to Southern Europe, and "Astraeus" are common in temperate and tropical regions.