Phallus impudicus Linnaeus, 1753
Common names: Common stinkhorn, Witch's egg (immature) [En], Satyre puant, Phallus impudique, Oeuf du Diable (immature) [Fr], Grote stinkzwam [Nl], Gemeine Stinkmorchel, Stinkmorchel [De], Satirione, Uovo del diavolo [It], Seta falo hediondo [Es], Φαλλός ο αναίσχυντος [Gr]
Tervuren, BRABANT ● Belgium
Taxonomy: Botanist John Gerard called it the “pricke mushroom” or “fungus virilis penis effigie” in his General Historie of Plants of 1597, and John Parkinson referred to it as “Hollanders workingtoole” or “phallus hollandicus” in his Theatrum botanicum of 1640. Linnaeus was responsible for the fairly obvious genus name. Its specific epithet, impudicus, is derived from the Latin for “shameless” or “immodest”.
Description: The immature stinkhorn is whitish or pinkish, egg-shaped, and typically 4 to 6 cm (1.6 to 2.4 in) by 3 to 5 cm (1.2 to 2.0 in). On the outside is a thick whitish volva, also known as the peridium, covering the olive-colored gelatinous gleba. It is the latter that contains the spores and later stinks and attracts the flies; within this layer is a green layer which will become the 'head' of the expanded fruit body; and inside this is a white structure called the receptaculum (the stalk when expanded), that is hard, but has an airy structure like a sponge. The eggs become fully grown stinkhorns very rapidly, over a day or two. The mature stinkhorn is 10 to 25 cm (3.9 to 9.8 in) tall and 4 to 5 cm (1.6 to 2.0 in) in diameter, topped with a conical cap 2 to 4 cm (0.8 to 1.6 in) high that is covered with a greenish-brown slime termed the gleba. In older fungi the slime is eventually removed, exposing a bare yellowish pitted and ridged (reticulate) surface. This has a passing resemblance to the common morel (Morchella esculenta), with which it is sometimes mistaken. The rate of growth of Phallus impudicus has been measured at 10–15 cm (3.9–5.9 in) per hour. The growing fruit body is able to exert up to 1.33 kN/m2 of pressure—a force sufficient to push up through asphalt.
The spores have an elliptical to oblong shape, with dimensions of 3–5 to 1.5–2.5 µm.
Biology : It appears from summer to late autumn. The dispersal of spores is different from most "typical" mushrooms that spread their spores through the air. Stinkhorns instead produce a sticky spore mass on their tip which has a sharp, sickly-sweet odor of carrion to attract flies and other insects. The mature fruiting bodies can be smelled from a considerable distance in the woods, and at close quarters most people find the cloying stink extremely repulsive. The flies land in the gleba and in doing so collect the spore mass on their legs and carry it to other locations.
Habitat: It occurs in habitats rich in wood debris such as forests and mulched gardens. The fungus is associated with rotting wood, and as such it is most commonly encountered in deciduous woods where it fruits from summer to late autumn, though it may also be found in conifer woods or even grassy areas such as parks and gardens. It may also form mycorrhizal associations with certain trees.
Distribution: Europe, North America, Asia and southeast Australia.
Wikipedia, Phallus impudicus