Scleroderma citrinum

{{Improve sources|date=January 2024}}

{{speciesbox

| image = Scleroderma citrinum.jpg

| taxon = Scleroderma citrinum

| authority = Pers.

}}

{{mycomorphbox

| name = Scleroderma citrinum

| whichGills = NA

| capShape = no

| hymeniumType= gleba

| stipeCharacter= NA

| ecologicalType=mycorrhizal

| sporePrintColor=purple-black

| howEdible=poisonous}}

File:Common earthball 1.jpg

Scleroderma citrinum, commonly known as the common earthball,{{Cite web |url=http://www.fungi4schools.org/Reprints/ENGLISH_NAMES.pdf |title=List of Recommended English Names For Fungi in the UK. |archive-url=https://web.archive.org/web/20110716083053/http://www.fungi4schools.org/Reprints/ENGLISH_NAMES.pdf |archive-date=2011-07-16 |website=Fungi 4 Schools |publisher=British Mycological Society |access-date=2007-09-17}} pigskin poison puffball,{{cite web |date=January 2005 |url=http://library.fws.gov/CCPs/oxbow_final05.pdf |title=Oxbow National Wildlife Refuge: Final Comprehensive Conservation Plan, January 2005 |publisher=U.S. Fish and Wildlife Service |p=195 |via=library.fws.gov |access-date=2007-09-17}} or common earth ball,{{cite journal |author=Falandysz J |title=Mercury in mushrooms and soil of the Tarnobrzeska Plain, south-eastern Poland |journal=J Environ Sci Health a Tox Hazard Subst Environ Eng |volume=37 |issue=3 |pages=343–52 |date=March 2002 |doi=10.1081/ese-120002833 |pmid=11929073 |s2cid=24124204 }} is a species of earthball fungus found in Europe and in North America. It is the most common species of earthball fungus in the UK and occurs widely in woods, heathland and in short grass from autumn to winter. Scleroderma citrinum has two synonyms, Scleroderma aurantium (Vaill.) and Scleroderma vulgare Horn.{{cite journal |author=Pekşen, Aysun and Gürsel Karaca |year=2003 |title=Macrofungi of Samsun Province |url=http://journals.tubitak.gov.tr/botany/issues/bot-03-27-3/bot-27-3-3-0204-3.pdf |journal=Turkish Journal of Botany |volume=27 |pages=173–184}}

Earthballs are superficially similar to, and considered look-alikes of, the edible puffball (particularly Apioperdon pyriforme), but whereas the puffball has a single opening on top through which the spores are dispersed, the earthball just breaks up to release the spores. Moreover, Scleroderma citrinum has much firmer flesh and a dark gleba (interior) much earlier in development than puffballs. Scleroderma citrinum has no stem but is attached to the soil by mycelial cords. The peridium, or outer wall, is thick and firm, usually ochre yellow externally with irregular warts.

Scleroderma citrinum is an ectomycorrhizal fungus with a symbiotic relationship with some tree species, and can influence the diversity of soil bacterial communities under some tree species.{{Cite web |title=Scleroderma citrinum - microbewiki |url=https://microbewiki.kenyon.edu/index.php/Scleroderma_citrinum |access-date=2024-09-02 |website=microbewiki.kenyon.edu |language=en}}

The earthball may be parasitized by Pseudoboletus parasiticus.

Scleroderma citrinum can be mistaken with truffles by inexperienced mushroom hunters. Ingestion of Scleroderma citrinum can cause gastrointestinal distress in humans and animals. Some individuals may experience lacrimation, rhinitis and rhinorrhea, and conjunctivitis from exposure to its spores.{{cite magazine |date=October 2006 |url=http://www.svims.ca/ff0610.pdf |title=Reflections on Mushroom Poisoning – Part III |magazine=Fungifama: The Newsletter of the South Vancouver Island Mycological Society |via=svims.ca |access-date=2007-09-17}}{{Cite web |last=Hoffman |first=Ursula |url=http://www.nemf.org/files/lincoff/beginners/poison.html |title=Poisonous Mushrooms in Northeastern North America |archive-url=https://web.archive.org/web/20040607082012/http://www.nemf.org/files/lincoff/beginners/poison.html |archive-date=2004-06-07 |publisher=NorthEast Mycological Federation, Inc. |access-date=2007-09-17}}

Pigments found in the fruiting body of Scleroderma citrinum Pers. are sclerocitrin, norbadione A, xerocomic acid, and badione A.