Puffball





A puffball is a member of any of a number of groups of fungus in the division Basidiomycota. The puffballs were previously treated as a taxonomic group called the Gasteromycetes or Gasteromycetidae, but they are now known to be a polyphyletic assemblage. Their distinguishing feature is that they have gasterothecia (gasteroid basidiocarps) in which the spores are produced internally; that is, the basidiocarp remains closed, or opens only after the spores have been released from the basidia. The spores of puffballs are statismospores rather than ballistospores, meaning they are not actively shot off the basidium. They are called puffballs because a cloud of brown dust-like spores is emitted when the mature fruiting body bursts. Puffballs and similar forms are thought to have evolved repeatedly (that is, in numerous independent events) from hymenomycetes by gasteromycetation, through secotioid stages. Thus Gasteromycetes or Gasteromycetidae are now considered descriptive terms (more properly gasteroid or gasteromycetes) and not valid cladistic terms.

Puffballs were traditionally used in Tibet for making ink by burning them vigorously, grinding them, then putting them in water and adding glue liquid and "a nye shing ma decoction", which, when pressed for a long time, made a very black dark substance which was used as an ink.

Habitat and structure
Puffballs are common on the ground in meadows and woods and on heaths or lawns, and a few species occur on decaying wood. When young, their fruiting bodies are whitish spheres, sometimes with short stalks, and are fleshy in texture. If cut across in this state, they show a compact rind enclosing a loose tissue, in the interspaces of which the spores are developed; as the fungus matures it darkens in color, typically to yellowish-brown or brown. When mature, the rind typically tears at the apex and the spores escape through the aperture when any pressure, even the impact of a raindrop, is applied to the outer sporecase. When white and fleshy, most puffballs are edible. The fibrous mass which remains after the spores have escaped has been used for tinder or as a styptic for wounds.

Edibility and identification
While most puffballs are not poisonous, and the poisonous puffballs are typically quite distinct from the non-poisonous ones, puffballs often look similar to young agarics, especially the deadly Amanitas, such as the Death Cap mushroom. It is for this reason that all puffballs gathered in mushroom hunting should be cut in half lengthwise. Young puffballs in the edible stage have undifferentiated white flesh within; the gills of immature Amanita mushrooms can be seen if they are closely examined.

The giant puffball, Calvatia gigantea (earlier classified as Lycoperdon giganteum), reaches a foot (30 cm) or more in diameter, and is difficult to mistake for any other fungus. It has been estimated that a large specimen of this fungus when mature will produce around 7 × 10¹² spores. If collected before spores have formed, while the flesh is still white, it may be cooked as slices fried in butter, with a strong earthy, mushroom flavor. It can often be used in recipes that would ordinarily call for eggplant. It does not store well in a freezer - the entire freezer rapidly acquires a strong mushroom odor.

Classification
Major orders:
 * Lycoperdales, Tulostomatales, Nidulariales (related to Agaricales),
 * Geastrales and Phallales (related to Cantharellales),
 * Sclerodermatales (related to Boletales)
 * and various false-truffles (hypogaeic gasteromycetes) related to different hymenomycete orders.

Similarly, the true truffles (Tuberales) are gasteroid Ascomycota. Their ascocarps are called tuberothecia.