Poronia punctata
Description
Poronia punctata is a very distinctive species, which looks rather like one of those flat-headed nails used to fix bituminous roofing felt to the roof of a garden shed. The cap of the fungus has distinctive pores, hence the generic name, Poronia.
It appears in autumn but persists through winter into spring. It can be found growing on dung in open areas, such as grassland and heathland, where ponies graze.
These tiny fungi are rare and so insubstantial as to be of no culinary interest - and in any case, they grow on dung so it is regarded as being inedible.
Common names: Nail Fungus, Porónia Bodkovaná (Slovakia ), Täpiline Jalgnööbik (Estonia), Grote Speldenprikzwam (Netherlands), Trusovka Tečkovaná (Czech Republic), Löcherscheibe, Großsporige Porenscheibe, Rossapfelkernpilz (Austria), Punktainā Poronija (Latvia).
Mushroom Identification
Description
The perithecia (ascomycetous fruitbody structures) are disc-like stroma, usually round or oval but sometimes lobed, 0.4 to 1.5cm across, occasionally developing a slightly raised margin at maturity. The disc is seated more or less centrally on a grey stem 0.5 to 1.5cm tall and 2 to 4mm in diameter. The fertile (upper) surface is white, becoming brownish particularly at the rim; matt; irregularly spotted with black pore openings via which spores are ejected.
Asci
180 x 18µm; eight spores per ascus.
Spores
Ellipsoidal to bean-shaped, smooth, 18-26 x 7-12µm; hyaline; with usually a single guttule (oil-like drop visible inside the spore).
Spore Print
Brownish black when fully mature
Odor and Taste
Not distinctive.
Habitat & Ecological Role
On pony dung in unimproved grassland habitats.
Look-Alikes
Poronia erici Lohmeyer & Benkert is common in Australia but very rare in most of Europe. This species is very similar to Poronia punctata but its fruitbodies are smaller, have almost no stems, and their spores are larger than those of Poronia punctata.
Uses
The isolation of punctaporonins and other bioactive compounds from P. punctata confirmed its aggressive attitude to competition, able to inhibit the growth of potential competitors (Anderson et al. 1984, Edwards et al. 1989, Gloer et al. 1988, Poyser 1986). The use of these compounds may be of interest for pharmaceutical industry (Granito and Lunghini 2006).
History
Carl Linnaeus described this little ascomycete fungus as long ago as 1753, when he in effect established its basionym (subsequently sanctioned by Elias Magnus Fries) by calling it Peziza punctata.
Almost a century later, in 1849, Fries transferred the Nail Fungus into its present genus, establishing its accepted scientific name as Poronia punctata.
Synonyms of Poronia punctata include Peziza punctata L., Sphaeria truncata Bolton, Sphaeria poronia (L.) Pers., and Hypoxylon punctatum (L.) Grev.
Poronia, the genus name, maybe from the Latin noun porus and means with pores - a reference to the holes in the top of the cap as these fungi do not have bolete-like under surfaces. If you have more information on the origin of Poronia please let us know.
The specific epithet punctata is more straightforward; this also of Latin origin and means having fine spots, dots, or puncture holes.
Photo sources:
Photo 1 - Author: bjoerns (CC BY-SA 4.0)
Photo 2 - Author: Nina Filippova (CC BY-SA 4.0)
Photo 3 - Author: Elsa (pinknailsgirl) (CC BY-SA 3.0)
Photo 4 - Author: Davide Puddu (Davide Puddu) (CC BY-SA 3.0)
Photo 5 - Author: Leoboudv (Public Domain)
