Omphalotus is a genus of basidiomycete mushroom, in the family Omphalotaceae, formally circumscribed by Victor Fayod in 1889. Members have the traditional cap and stem structure. They are saprobic, and fruit in clumps on the ground, adjacent to host trees. The best known and type species is the jack-o'-lantern mushroom (Omphalotus olearius). Species of Omphalotus have been mistaken for chanterelles. All Omphalotus species are presumed poisonous, causing gastrointestinal symptoms. Some Omphalotus species have bioluminescent properties.
Omphalotus
Image: 2007 08 05 Omphalotus illudens (Schwein.) Bresinsky & Besl 1018098506
Image: Omphalotus guepiniformis Berk Neda 02
Image: Omphalotus mexicanus 183620
A mushroom or toadstool is the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground, on soil, or on its food source. Toadstool generally denotes one poisonous to humans.
Culinary mushrooms in a diversity of shapes and colors
Amanita muscaria, the most easily recognised "toadstool", is frequently depicted in fairy stories and on greeting cards. It is often associated with gnomes.
Maitake, a polypore mushroom
A mushroom (probably Russula brevipes) parasitized by Hypomyces lactifluorum resulting in a "lobster mushroom"