Lactarius turpis
Description
Lactarius turpis is a large dull olive-brown mushroom that is slimy and sticky. As with all milkcaps, it exudes a white milky latex if broken. It exudes copious white milk when the flesh is cut.
This species is reported to contain the mutagen necatorin (=7-hydroxycoumaro(5,6-c)cinnoline), and so it cannot be recommended for eating. Boiling reduces the concentration of this compound, but does not effectively eliminate it.
Probably due to the acrid taste, most western European authorities classify this mushroom as inedible or poor. However, it has popularly been used (after boiling) as a spice in mushroom dishes in northern and eastern Europe and Siberia. It is commercially available preserved in salt. Considered a choice mushroom in Russia, one of the best for pickling (salt only, no vinegar).
Common names: Ugly Milk Cap.
Mushroom Identification
Cap
Dark olive-brown with a paler margin, the cap of Lactarius turpis is slimy when wet; initially convex, the center usually becomes slightly depressed and occasionally retains a small umbo.
Caps generally range from 7 to 18cm across when fully developed.
Gills
Cream to pale buff, becoming sepia-tinged when bruised; decurrent; narrow and crowded. When damaged the gills exude an abundant white latex, which dries olivaceous.
Stem
Color as cap or lighter; cylindrical, tapering near base; 4 to 7cm long, 1 to 2.5cm dia.; no stem ring.
Spores
Ellipsoidal, 6.5-7.5 x 5.5-6μm, ornamented with warty ridges forming a well-developed network.
Spore Print
Creamy white.
Similar Species
Lactarius blennius, the Beech Milkcap, is lighter and smaller; it does not develop sepia-tinged areas on its gills.
History
This mushroom was described scientifically in 1828 by German mycologist Johann Anton Weinmann.(1782 - 1858), who named it Agaricus turpis.
Lactarius turpis was transferred to the genus Lactarius in 1838 by the great Swedish mycologist Elias Magnus Fries, whereupon it became Lactarius turpis, by which name it is generally known today.
Synonyms of Lactarius turpis include Agaricus turpis Weinm., Galorrheus turpis (Weinm.) P. Kumm., and Lactifluus turpis (Weinm.) Kuntze
The generic name Lactarius means producing milk (lactating) - a reference to the milky latex that is exuded from the gills of milkcap fungi when they are cut or torn. The specific epithet turpis comes directly from Latin and means ugly.
Photo sources:
Photo 1 - Author: Георгий Виноградов (Georgy Vinogradov) (CC BY-SA 4.0)
Photo 2 - Author: George Chernilevsky (Public Domain)
Photo 3 - Author: mangoblatt (Public Domain)
Photo 4 - Author: Renette Louw (Public Domain)