Lactarius turpis

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Lactarius turpis
L. turpis
L. turpis
Scientific classification
Kingdom: Fungi
Division: Basidiomycota
Order: Russulales
Family: Russulaceae
Genus: Lactarius
Species: L. turpis
Binomial name
Lactarius turpis
Fr (1838)
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Lactarius turpis
mycological characteristics:
 
gills on hymenium
 

cap is depressed

 

hymenium is decurrent

 

stipe is bare

 

spore print is white

 

ecology is mycorrhizal

 

edibility: inedible

Lactarius turpis (also L. plumbeus or L. necator)[1] is sometimes known as the Ugly Milk-cap in English. It is found naturally in Europe and Siberia, and has been introduced to Australia and New Zealand. While especially associated with birch, it is also found with spruce, pine and other trees in mixed woodland.

The messy, dirty appearance, seen in the photograph, is characteristic of the species and gives it its English name and the Latin species epithet, turpis. It seems to collect debris on top and the gills acquire a dirty brownish stain due to discoloured milk.

Contents

[edit] Taxonomy and naming

This very variable mushroom demonstrates a common phenomenon in mycology as there is much disagreement over naming. The three main scientific designations:

are usually[2], but not always[3], considered to be synonyms for same species. The epithets necator and plumbeus were both coined by Pierre Bulliard as Agaricus necator (1791) and Agaricus plumbeus (1793), but there is and was confusion as to which mushrooms were meant. The name turpis, derived from the latin term turpis "ugly",[4] was originated by Johann Anton Weinmann and taken over by Elias Magnus Fries in 1838[5]. Plumbeus too referred to the milk-cap's appearance, derived from the Latin for plumbeus "lead-coloured".

[edit] Description

L. turpis
L. turpis

[2][5][6][7][8]

The cap is normally 8-20 cm (3-8 in) in diameter. At first it has an involute margin and a somewhat depressed centre. The upper surface is olive brown or yellow-green and is often sticky or slimy in the middle. When young it has velvety zones and may be shaggy at the rim. Later it becomes funnel-shaped and the colour darkens to blackish. The gills are dirty white, stained olive-brown by old milk, which is initially white on contact with the air. They are somewhat decurrent. With potassium hydroxide or ammonia there is a purple reaction. The stipe is up to about 7 cm (3 in) tall by 3 cm (1¼ in) in diameter and it is similar in colour to the cap, but much lighter. It may have shallow pits (scrobiculae). The flesh is a dirty white and tends to turn brown. The taste (especially the milk) is acrid. There is little smell. The spores are about 7x6 µ and are ornamented with a pattern of ridges.

[edit] Edibility

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. [9]

Probably due to the acrid taste, most western European authorities classify this mushroom as inedible[6] or poor[2][5]. However, it has popularly been used (after boiling) as a spice in mushroom dishes in northern and eastern Europe and Siberia (see Mushroom picking in Slavic culture). It is commercially available preserved in salt[10].

[edit] References

  1. ^ See the entry in Index Fungorum for the current name and synonyms.
  2. ^ a b c Marcel Bon: "The Mushrooms and Toadstools of Britain and North-Western Europe" Hodder & Stoughton ISBN 0-340-39935-X.
  3. ^ Machiel E. Noordeloos & Thomas W. Kuyper "Notulae ad Floram agaricinam neerlandicam XXXV – On the typification of Lactarius necator", Persoonia Volume 17 - 2 1999 (abstract)
  4. ^ Simpson, D.P. (1979). Cassell's Latin Dictionary, 5, London: Cassell Ltd., 883. ISBN 0-304-52257-0. 
  5. ^ a b c R.F.R.McNabb "The Russulaceae of New Zealand. 1. Lactarius DC ex S.F. Gray". New Zealand Journal of Botany 9(1): 46-66 (1971) (see here).
  6. ^ a b Phillips, Roger (1981) Entry in "Mushrooms and other fungi of Great Britain & Europe" published by Pan Books Ltd., Cavaye Place, London SW10 9PG
  7. ^ Meinhard Moser, translated by Simon Plant: Keys to Agarics and Boleti (Roger Phillips 1983) ISBN 0-9508486-0-3
  8. ^ Courtecuisse, R. & Duhem, B. (1994) "Guide des champignons de France et d'Europe" Delachaux et Niestlé ISBN 2-603-00953-2, also available in English.
  9. ^ See T. Suortti: "Stability of necatorin, a highly mutagenic compound from Lactarius necator mushroom", Food and Chemical Toxicology 1984 Jul ;22 (7):579-81 6547686. (abstract) and A. von Wright & T. Suortti "Preliminary characterization of the mutagenic properties of 'necatorin', a strongly mutagenic compound of the mushroom Lactarius necator." Mutation Research 1983 Aug;121(2):103-6. (abstract).
  10. ^ See site of YeniseyEcoproduct, Krasnoyarsk