The Russulaceae are a diverse family of fungi in the order Russulales, with roughly 1,900 known species and a worldwide distribution. They comprise the brittlegills and the milk-caps, well-known mushroom-forming fungi that include some edible species. These gilled mushrooms are characterised by the brittle flesh of their fruitbodies.
Lactarius is a genus of mushroom-producing, ectomycorrhizal fungi, containing several edible species. The species of the genus, commonly known as milk-caps, are characterized by the milky fluid ("latex") they exude when cut or damaged. Like the closely related genus Russula, their flesh has a distinctive brittle consistency. It is a large genus with over 500 known species, mainly distributed in the Northern hemisphere. Recently, the genus Lactifluus has been separated from Lactarius based on molecular phylogenetic evidence.
Lactarius deliciosus, commonly known as the delicious milk cap, saffron milk cap and red pine mushroom, is one of the best known members of the large milk-cap genus Lactarius in the order Russulales. It is native to Europe, but has been accidentally introduced to other countries along with pine trees, with which the fungus is symbiotic.
Milk-cap is a common name that refers to mushroom-forming fungi of the genera Lactarius, Lactifluus, and Multifurca, all in the family Russulaceae. The common and eponymous feature of their fruitbodies is the latex ("milk") they exude when cut or bruised. Mushrooms with typical milk-cap characteristics are said to have a lactarioid habit. Some of them are edible.
Lactarius blennius is a medium-sized mushroom of the genus Lactarius found commonly in beech forests in Europe, where it is mycorrhizal, favouring the European beech. It was first described by Elias Magnus Fries. Though its colour and size vary, it is distinctive because it is slimy when wet and exudes copious amounts of milk. It has been the subject of some chemical research, and it can be used to produce pigments and blennins. Blennins, some of which have shown potential medical application, are derived from lactarane, a chemical so named because of their association with Lactarius. The edibility of L. blennius is uncertain, with different mycologists suggesting that it is edible, inedible or even poisonous.
Lactifluus volemus, formerly known as Lactarius volemus, and commonly known as the weeping milk cap or bradley, is a species of fungus in the family Russulaceae. It is widely distributed in the northern hemisphere, in temperate regions of Europe, North America and Asia as well as some subtropical and tropical regions of Central America and Asia. A mycorrhizal fungus, its fruit bodies grow on the ground at the base of various species of trees from summer to autumn, either individually or in groups. It is valued as an edible mushroom, and is sold in markets in Asia. Several other Lactifluus mushrooms resemble L. volemus, such as the closely related edible species L. corrugis, but these can be distinguished by differences in distribution, visible morphology, and microscopic characteristics. L. volemus produces a white spore print and has roughly spherical spores about 7–8 micrometres in diameter.
Lactarius vietus is a species of fungus in the family Russulaceae, first described by Elias Magnus Fries. It produces moderately sized and brittle mushrooms, which grow on the forest floor or on rotting wood. The flattened-convex cap can vary in shape, sometimes forming the shape of a wide funnel. It is typically grey, but the colour varies. The species has crowded, light-coloured gills, which produce white milk. The spore print is typically whitish, but also varies considerably. The mushrooms typically have a strong, acrid taste and have been described as inedible, but other authors have described them as consumable after boiling. L. vietus feeds by forming an ectomycorrhizal relationship with surrounding trees, and it favours birch. It grows in autumn months and is fairly common in Europe, North America and eastern Asia.
Lactarius indigo, commonly known as the indigo milk cap, indigo milky, the indigo lactarius, or the blue milk mushroom, is a species of agaric fungus in the family Russulaceae. It is a widely distributed species, growing naturally in eastern North America, East Asia, and Central America; it has also been reported in southern France. L. indigo grows on the ground in both deciduous and coniferous forests, where it forms mycorrhizal associations with a broad range of trees. The fruit body color ranges from dark blue in fresh specimens to pale blue-gray in older ones. The milk, or latex, that oozes when the mushroom tissue is cut or broken — a feature common to all members of the genus Lactarius — is also indigo blue, but slowly turns green upon exposure to air. The cap has a diameter of 5–15 cm (2–6 in), and the stem is 2–8 cm (0.8–3 in) tall and 1–2.5 cm (0.4–1.0 in) thick. It is an edible mushroom, and is sold in rural markets in China, Guatemala, and Mexico. In Honduras, the mushroom is called a chora, and is generally eaten with egg; generally as a side dish for a bigger meal.
Lactarius sanguifluus, commonly known as the bloody milk cap, is a species of fungus in the family Russulaceae. First described from France in 1811, the species was given its current name by Elias Fries in 1838 when he transferred it to Lactarius. Found in Asia, Mediterranean Africa, and Europe, fruit bodies (mushrooms) grow scattered or in groups on the ground under conifers, especially Douglas fir. When bruised or cut, the fruit bodies ooze a blood-red to purple latex that slowly turns greenish upon exposure to air. The caps are orangish to reddish-brown, and become funnel-shaped with age. The gills are pinkish to purplish. Different forms have been described from Italy, but these are not universally accepted as distinct. L. sanguifluus mushrooms are edible, and sold in rural markets of Europe and Asia. Fruit bodies grown in polluted soil, including roadsides subject to heavy traffic, can bioaccumulate toxic heavy metals. Several sterols and pigment have been isolated and identified from the mushrooms.
Lactarius subflammeus, commonly known as the orange milk cap, is a species of fungus in the family Russulaceae. It is found in western North America in the late summer and fall and is especially common in the Pacific Northwest, where it grows on the ground near conifers like pine and spruce. The brightly colored fruit bodies, which are slimy or sticky, have scarlet caps when young that soon fade to brilliant orange. The stem—typically longer than the width of the cap—is also bright orange but the gills are whitish. The mushroom secretes a whitish latex when it is cut or injured.
Lactarius pubescens, commonly known as the downy milk cap, is a species of fungus in the family Russulaceae. It is a medium to large agaric with a creamy-buff, hairy cap, whitish gills and short stout stem. The fungus has a cosmopolitan distribution, and grows solitarily or in scattered groups on sandy soil under or near birch.
Lactarius repraesentaneus, commonly known as the northern bearded milkcap, the northern milkcap, or the purple-staining bearded milkcap, is a species of fungus in the family Russulaceae. It has a northerly distribution, and is found in temperate regions of North America and Europe, associated with spruce trees. Distinguishing features of its fruit body include the large orange-yellow cap up to 18 cm (7.1 in) wide, cream to pale yellow gills, and a yellow coarsely-pitted stem that is up to 12 cm (4.7 in) long and 3 cm (1.2 in) thick. Cut fruit bodies ooze a white latex that will stain mushroom tissue lilac to purple. Several chemicals have been isolated and identified from the fruit bodies that can modify the growth of plants, and the mushroom also has antibiotic activity against Staphylococcus aureus. L. repraesentaneus is poisonous, and consumption causes stomach aches.
Lactarius affinis, commonly known as the kindred milk cap, is a species of milk-cap mushroom in the family Russulaceae. It is found northeastern North America, where it fruits in the summer and fall, and is common in the Great Lakes region. Its fruit bodies have medium to large, slimy dull yellow or brownish caps. Although not considered poisonous, it is unpalatable because of its highly acrid taste.
Lactifluus deceptivus, commonly known as the deceiving milkcap, is a common species of fungus in the family Russulaceae. It is found throughout eastern North America on the ground in coniferous forests near hemlock or deciduous forests near oak, and in oak-dominated forests of Costa Rica. It produces large mushrooms with funnel-shaped caps reaching up to 25 cm (9.8 in) in diameter, on top of hard white stems that may reach 4–10 cm (1.6–3.9 in) long and up to 3 cm (1.2 in) thick. The gills are closely spaced together and yellowish-cream in color. When young, the cap is white in all parts, but the depressed center becomes dull brownish in age and breaks up into scales. The edge of the cap has a roll of cottony tissue that collapses as the cap expands. The surface of the stem—especially near the base—has a velvety texture. The mushroom "bleeds" a milky white acrid latex when it is cut or injured. Similar milk-cap species with which L. deceptivus might be confused include Lactifluus piperatus, L. pseudodeceptivus, L. caeruleitinctus, L. subvellereus, Lactarius arcuatus and Lactarius parvulus.
Lactarius rufulus, commonly known as the rufous candy cap, is a species of fungus in the family Russulaceae. The fruit bodies have fleshy brownish-red caps up to 10 cm (3.9 in) wide, and closely spaced pinkish-yellow gills. The stem is up to 12 cm (4.7 in) long and 3 cm (1.2 in) thick and colored similarly to the cap. The species, known only from California, Arizona, and Mexico, grows on the ground in leaf litter near oak trees. The fruit bodies resembles those of L. rufus, but L. rufulus tends to grow in clusters at a common base, rather than solitarily or in groups. A distinguishing microscopic characteristic is the near absence of large, spherical cells called sphaerocysts that are otherwise common in Lactarius species. Lactarius rufulus mushrooms are edible, and have an odor resembling maple syrup. They have been used to flavor confections and desserts.
Lactarius vinaceorufescens, commonly known as the yellow-staining milkcap or the yellow-latex milky, is a poisonous species of fungus in the family Russulaceae. It produces mushrooms with pinkish-cinnamon caps up to 12 cm (4.7 in) wide held by pinkish-white stems up to 7 cm (2.8 in) long. The closely spaced whitish to pinkish buff gills develop wine-red spots in age. When it is cut or injured, the mushroom oozes a white latex that rapidly turns bright sulfur-yellow. The species, common and widely distributed in North America, grows in the ground in association with conifer trees. There are several other Lactarius species that bear resemblance to L. vinaceorufescens, but most can be distinguished by differences in staining reactions, macroscopic characteristics, or habitat.
Lactarius fuliginosus, commonly known as the sooty milkcap, is a species of fungus in the family Russulaceae. The medium-sized fruit bodies have velvety, grayish-brown caps and crowded gills. It is found in deciduous forests of Asia, Europe, and North America.
Lactifluus is one of three genera of mushroom-forming fungi containing species commonly named "milk-caps", the others being Lactarius and Multifurca. It has been separated from Lactarius based on molecular phylogenetic evidence but is very similar to that genus. There are roughly 150 known Lactifluus species, which have a mainly tropical distribution but are also found in the north temperate zone and Australasia. Some of them are edible mushrooms.
