Coprinus sterquilinus
Description
Coprinus sterquilinus is a species of fungus in the family Agaricaceae. It grows on animal dung and occurs in Europe, Asia, and America. It has an ellipsoid or ovoid cap, becoming conical and then flattening out. It is white, flocculous and fibrillose when young, becoming more scaly with a creamy center as it matures. There are more than fifty gills, white at first, turning to grey and then black. The stipe or stem is slender with a moveable ring just above the slightly bulbous base. The spores are ellipsoid and very large, very dark reddish-brown to black.
This mushroom is closely related to the shaggy ink cap (Coprinus comatus). Both share the characteristic of the genus to autodigest; starting at the base of the gills, the spores develop and discharge, and the discharged basidia and the supporting hyphae produce enzymes that dissolve the tissues, and these drip from the base of the gills as a black liquid (which can be used as ink).
Common names: Midden Ink Cap.
Mushroom Identification
Cap
Initially egg-shaped and opening into a bell shape, the shaggy caps of Coprinus sterquilinus are at first pure white. Typically 2-6cm tall and 1.5-3cm wide, the white caps darken and become fibrillose and open to a somewhat plicate final shape, looking like many other inkcaps at this stage. The cap is also prone to reddening with damage and age.
Gills
The adnexed to free gills of Coprinus sterquilinus are crowded and initially white; they soon turn pink and then black before deliquescing (liquefying) from the outside edge.
Stem
The stem of the Midden Inkcap widens downwards with a basal bulb, 6-15cm tall and 3-10mm in diameter; white, with a loose narrow ring.
Spores
Ellipsoidal, smooth, 17-22 x 10-13µm; with a germ pore positioned centrally or slightly eccentrically.
Spore Print
Black.
Odor and Taste
Faint and quite pleasant, but not distinctive.
Habitat & Ecological Role
This saprobic mushroom has been found on weathered horse dung, occasionally with rabbit dung, and on rotten plant debris. The earliest reports of this fungus on the FRDBI are from the 19th century when it was found on local tips. An important identification feature is that this fungus is found on weathered dung rather than on the ground.
History
The scientific name was applied to this species by Elias Magnus Fries in 1838, since when it has remained unchanged.
In the era before motor vehicles, when horses were the main form of transport, the local domestic tip would contain a fair amount of horse dung and rotting vegetation. These tips were known as 'middens', and early records show that this is where Coprinus sterquilinus could be found - hence the common name Midden Inkcap.
After the taxonomic re-evaluation of the Coprinus genus in 2008 by Redhead, Vilgalys & Moncalvo, this fungus and Coprinus comatus are the only members of the genus Coprinus reliably found in Britain.
The generic name Coprinus means 'living on dung' - that's true of many of the inkcaps and quite apt for this species.
The specific epithet sterquilinus means 'of dung heaps'.
Photo sources:
Photo 1 - Author: Copyright ©2011 TimmiT (CC BY-SA 3.0)
Photo 2 - Author: Copyright ©2011 TimmiT (CC BY-SA 3.0)
Photo 3 - Author: Copyright ©2011 TimmiT (CC BY-SA 3.0)
Photo 4 - Author: Copyright ©2011 TimmiT (CC BY-SA 3.0)
Photo 5 - Author: Copyright ©2011 TimmiT (CC BY-SA 3.0)