These species are covered in two keys: the puffballs and earthstars in the Key to Lycoperdaceae and Geastraceae, and the earthballs in the Key to Sclerodermataceae.

The Key to LYCOPERDACEAE and GEASTRACEAE covers the genera Bovista, Calbovista, Calvatia, Disciseda, Lycoperdon, Mycenastrum, Myriostoma, Vascellum, Geastrum, and for convenience Astraeus. Sphaerobolus, the cannon-ball fungus, is presently in Geastraceae, but it is considered instead under BIRD'S NEST FUNGI.

The SCLERODERMATACEAE key covers Scleroderma, Astraeus, and Pisolithus.

A third key is planned that will cover stalked puffballs (Tulostoma and a few others). These groups have in common that they do not forcibly discharge their spores. The spore mass develops inside the fruitbody and becomes powdery with maturity. After rupture, the wind is able to blow the spores to other locations.

Earthballs differ from puffballs in having a thicker, hard to tough outer rind, and when the spore mass becomes dark, it remains firm rather than becoming soft. There is no sterile base.

Earthstars have two layers to the spore case, of which the outer splits in star-like fashion to expose the inner layer. The star-like limbs can curl back to act like feet, sometimes doing so only in wet weather and closing again when weather is dry.

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