Collared Earthstar (Geastrum triplex)
Although an infrequent and rather localised species, G. triplex is probably the most commonly found of the British Geastrum species.
Initially appearing as a part-buried ball with a prominent beak, the mature fruiting body eventually comprises of an outer star, an inner saucer-like collar (sometimes), and a central spore sac. The onion-shaped fruitbody splits open at maturity and 5 to 8 creamy-buff outer rays fold back, splitting to sometimes leave a fleshy collar as the remainder of each ray folds downwards and the tips curl partway under the body. A pointed hole, known as a peristome, situated on top of the sac releases spores when the wind blows across it or raindrops impinge upon its surface. The sides of the peristome are fibrous and appear rather ragged but not regularly striate. A fuzzy ring surrounds the peristome, which is slightly paler fawn-brown than the rest of the outer surface of the spore-sac.
With their extraterrestrial appearance members of the Geastraceae are always a pleasure to find …
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