is a genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of fungi, commonly known as earth balls
, now known to belong to the Boletales
The Boletales are an order of Agaricomycetes, containing over 1300 species with a diverse array of fruiting body types. The boletes are the best known members of this group, and until recently, the Boletales were thought to only contain boletes...
order, in suborder Sclerodermatineae.. The best known species are S. citrinum
Scleroderma citrinum, commonly known as the common earthball, pigskin poison puffball, or common earth ball, is the most common species of earthball in the UK and occurs widely in woods, heathland and in short grass from Autumn to Winter.Scleroderma citrinum has two synonyms, Scleroderma aurantium ...
and S. verrucosum
. They are found worldwide.
Various members of this genus are used as inoculation symbionts to colonize and promote the growth of tree seedlings in nurseries.
The name comes from the Greek sclera
The peridium is the protective layer that encloses a mass of spores in fungi. This outer covering is a distinctive feature of the Gasteromycetes.-Description:...
(outer wall), which may be smooth or warted, is very thick, tough, and persistent. At maturity it splits irregularly over the upper part of the basidiocarp
In fungi, a basidiocarp, basidiome or basidioma , is the sporocarp of a basidiomycete, the multicellular structure on which the spore-producing hymenium is borne. Basidiocarps are characteristic of the hymenomycetes; rusts and smuts do not produce such structures...
to reveal the dark gleba
Gleba is the fleshy spore-bearing inner mass of fungi such as the puffball or stinkhorn.The gleba is a solid mass of spores, generated within an enclosed area within the sporocarp. The continuous maturity of the sporogenous cells leave the spores behind as a powdery mass that can be easily blown away...
In biology, a spore is a reproductive structure that is adapted for dispersal and surviving for extended periods of time in unfavorable conditions. Spores form part of the life cycles of many bacteria, plants, algae, fungi and some protozoa. According to scientist Dr...
s are produced in small brownish-purple, pea-like bodies called peridioles that initially are outlined by wall-like aggregations of white hyphae. These peridioles disintegrate as the fruit body matures, and by the time the peridium splits open, only a powdery mass of dark spores is visible. Spores are roughly spherical in shape with warts or reticulate ornamentation, thick-walled, and brown. Species in Scleroderma
are ectomycorrhizal with shrubs and trees, and have a worldwide distribution.