Lactarius affinis
Encyclopedia
Lactarius affinis, commonly known as the kindred milk cap, is a species of fungus
in the Russulaceae
family. 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.
in 1873, based on specimens he found growing in a pasture in the Catskill Mountains
in October. He noted that the species was similar in appearance to Lactarius insulus, "from which it differs only in the entire absence of zones or bands, and in having the spores white, instead of yellow ... But for the color of the spores, I should not have separated it from L. insulus."
The species is classified in section Triviales of the subgenus
Russularia of the genus Lactarius
. Species in this section typically have sticky or tacky caps and stems, with hypha
e on the cap cuticle usually 1–3 µm
wide. Other species in Triviales (stirps Trivialis) include L. midlandensis, L. vinaceopallidus, L. trivialis, L. pallidus
, and L. limacinus.
Lactarius affinis is commonly
known as the "kindred milk cap".
is 5 – wide, initially convex, becoming broadly convex then shallowly depressed at the center with age. The surface of the cap is sticky to slimy when it is fresh, smooth, pale ochre-yellow to pale ochre or pale pinkish cinnamon, lighter toward the edge. The gills are attached to slightly decurrent, close, broad, sometimes forked near the stem, white to cream. The stalk
in 3 – long by 1.2 – thick, nearly equal, becoming hollow with age, smooth, sticky when fresh, white or sometimes brownish. The flesh
is white, and does not have any distinctive odor; taste acrid. The latex
is white on exposure, unchanging, not staining tissues; taste acrid. The spore print
is white. Although not considered poisonous, it is unpalatable because of its highly acrid taste.
s are 8–10.5 by 7–8 µm
, broadly ellipsoid, ornamented with warts and ridges that sometimes form a partial reticulum, prominences up to 1 µm high, hyaline
(translucent), and amyloid
. The basidia, the spore-bearing cells, are 45–52 by 8–10 µm, and four-spored.
, west to Michigan
. It has also reported from western Canada. Its frequency of occurrence is occasional. It is common in the Great Lakes
area.
Fungus
A fungus is a member of a large group of eukaryotic organisms that includes microorganisms such as yeasts and molds , as well as the more familiar mushrooms. These organisms are classified as a kingdom, Fungi, which is separate from plants, animals, and bacteria...
in the Russulaceae
Russulaceae
The Russulaceae are a family of fungi in the order Russulales. According to a 2008 estimate, the family contains 1243 species. Its species typically have fruit bodies with friable, chalk-like stalks, that break with a distinct crack, somewhat like a carrot but with porous flesh...
family. It is found northeastern North America, where it fruits in the summer and fall, and is common in the Great Lakes
Great Lakes
The Great Lakes are a collection of freshwater lakes located in northeastern North America, on the Canada – United States border. Consisting of Lakes Superior, Michigan, Huron, Erie, and Ontario, they form the largest group of freshwater lakes on Earth by total surface, coming in second by volume...
region. Its fruit bodies
Basidiocarp
In fungi, a basidiocarp, basidiome or basidioma , is the sporocarp of a basidiomycete, the multicellular structure on which the spore-producing hymenium is borne. Basidiocarps are characteristic of the hymenomycetes; rusts and smuts do not produce such structures...
have medium to large, slimy dull yellow or brownish caps
Pileus (mycology)
The pileus is the technical name for the cap, or cap-like part, of a basidiocarp or ascocarp that supports a spore-bearing surface, the hymenium. The hymenium may consist of lamellae, tubes, or teeth, on the underside of the pileus...
. Although not considered poisonous, it is unpalatable because of its highly acrid taste.
Taxonomy and classification
The species was first named by American mycologist Charles Horton PeckCharles Horton Peck
Charles Horton Peck, born March 30, 1833 in Sand Lake, New York, died 1917 in Albany, New York, was an American mycologist of the 19th and early 20th centuries...
in 1873, based on specimens he found growing in a pasture in the Catskill Mountains
Catskill Mountains
The Catskill Mountains, an area in New York State northwest of New York City and southwest of Albany, are a mature dissected plateau, an uplifted region that was subsequently eroded into sharp relief. They are an eastward continuation, and the highest representation, of the Allegheny Plateau...
in October. He noted that the species was similar in appearance to Lactarius insulus, "from which it differs only in the entire absence of zones or bands, and in having the spores white, instead of yellow ... But for the color of the spores, I should not have separated it from L. insulus."
The species is classified in section Triviales of the subgenus
Subgenus
In biology, a subgenus is a taxonomic rank directly below genus.In zoology, a subgeneric name can be used independently or included in a species name, in parentheses, placed between the generic name and the specific epithet: e.g. the Tiger Cowry of the Indo-Pacific, Cypraea tigris Linnaeus, which...
Russularia of the genus Lactarius
Lactarius
Lactarius is a genus of mushroom-producing fungi. The genus, collectively known commonly as milk-caps, are characterized by the fact that they exude a milky fluid if cut or damaged...
. Species in this section typically have sticky or tacky caps and stems, with hypha
Hypha
A hypha is a long, branching filamentous structure of a fungus, and also of unrelated Actinobacteria. In most fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium; yeasts are unicellular fungi that do not grow as hyphae.-Structure:A hypha consists of one or...
e on the cap cuticle usually 1–3 µm
Micrometre
A micrometer , is by definition 1×10-6 of a meter .In plain English, it means one-millionth of a meter . Its unit symbol in the International System of Units is μm...
wide. Other species in Triviales (stirps Trivialis) include L. midlandensis, L. vinaceopallidus, L. trivialis, L. pallidus
Lactarius pallidus
Lactarius pallidus is an edible mushroom of the genus Lactarius. It is pale in colour, and found on the floor in beech or birch woodland. Its smooth cap features a particularly thick layer of flesh, and often has an incurved margin. Though generally considered edible, it is not recommended to be...
, and L. limacinus.
Lactarius affinis is commonly
Common name
A common name of a taxon or organism is a name in general use within a community; it is often contrasted with the scientific name for the same organism...
known as the "kindred milk cap".
Description
The capPileus (mycology)
The pileus is the technical name for the cap, or cap-like part, of a basidiocarp or ascocarp that supports a spore-bearing surface, the hymenium. The hymenium may consist of lamellae, tubes, or teeth, on the underside of the pileus...
is 5 – wide, initially convex, becoming broadly convex then shallowly depressed at the center with age. The surface of the cap is sticky to slimy when it is fresh, smooth, pale ochre-yellow to pale ochre or pale pinkish cinnamon, lighter toward the edge. The gills are attached to slightly decurrent, close, broad, sometimes forked near the stem, white to cream. The stalk
Stipe (mycology)
thumb|150px|right|Diagram of a [[basidiomycete]] stipe with an [[annulus |annulus]] and [[volva |volva]]In mycology a stipe refers to the stem or stalk-like feature supporting the cap of a mushroom. Like all tissues of the mushroom other than the hymenium, the stipe is composed of sterile hyphal...
in 3 – long by 1.2 – thick, nearly equal, becoming hollow with age, smooth, sticky when fresh, white or sometimes brownish. The flesh
Trama (mycology)
In mycology trama is a term for the inner, fleshy portion of a mushroom's basidiocarp, or fruit body. It is distinct from the outer layer of tissue, known as the pileipellis or cuticle, and from the spore-bearing tissue layer known as the hymenium....
is white, and does not have any distinctive odor; taste acrid. The latex
Latex
Latex is the stable dispersion of polymer microparticles in an aqueous medium. Latexes may be natural or synthetic.Latex as found in nature is a milky fluid found in 10% of all flowering plants . It is a complex emulsion consisting of proteins, alkaloids, starches, sugars, oils, tannins, resins,...
is white on exposure, unchanging, not staining tissues; taste acrid. The spore print
Spore print
thumb|300px|right|Making a spore print of the mushroom Volvariella volvacea shown in composite: mushroom cap laid on white and dark paper; cap removed after 24 hours showing pinkish-tan spore print...
is white. Although not considered poisonous, it is unpalatable because of its highly acrid taste.
Microscopic characteristics
The sporeSpore
In biology, a spore is a reproductive structure that is adapted for dispersal and surviving for extended periods of time in unfavorable conditions. Spores form part of the life cycles of many bacteria, plants, algae, fungi and some protozoa. According to scientist Dr...
s are 8–10.5 by 7–8 µm
Micrometre
A micrometer , is by definition 1×10-6 of a meter .In plain English, it means one-millionth of a meter . Its unit symbol in the International System of Units is μm...
, broadly ellipsoid, ornamented with warts and ridges that sometimes form a partial reticulum, prominences up to 1 µm high, hyaline
Hyaline
The term hyaline denotes a substance with a glass-like appearance.-Histopathology:In histopathological medical usage, a hyaline substance appears glassy and pink after being stained with haematoxylin and eosin — usually it is an acellular, proteinaceous material...
(translucent), and amyloid
Amyloid (mycology)
In mycology the term amyloid refers to a crude chemical test using iodine in either Melzer's reagent or Lugol's solution, to produce a black to blue-black positive reaction. It is called amyloid because starch gives a similar reaction, and that reaction for starch is also called an amyloid reaction...
. The basidia, the spore-bearing cells, are 45–52 by 8–10 µm, and four-spored.
Similar species
Similar species include Lactarius depressus, L. midlandensis, and L. pseudoaffinis. Russula laurocerasi has a somewhat similar cap and could be confused with this species, but it does not have latex, and smells somewhat like almonds or maraschino cherries.Habitat and distribution
Fruit bodies of Lactarius affinis are found scattered or in groups on the ground in conifer or hardwood forests from July to October. They are distributed in eastern Canada south to New YorkNew York
New York is a state in the Northeastern region of the United States. It is the nation's third most populous state. New York is bordered by New Jersey and Pennsylvania to the south, and by Connecticut, Massachusetts and Vermont to the east...
, west to Michigan
Michigan
Michigan is a U.S. state located in the Great Lakes Region of the United States of America. The name Michigan is the French form of the Ojibwa word mishigamaa, meaning "large water" or "large lake"....
. It has also reported from western Canada. Its frequency of occurrence is occasional. It is common in the Great Lakes
Great Lakes
The Great Lakes are a collection of freshwater lakes located in northeastern North America, on the Canada – United States border. Consisting of Lakes Superior, Michigan, Huron, Erie, and Ontario, they form the largest group of freshwater lakes on Earth by total surface, coming in second by volume...
area.