Lactarius aspideoides
Encyclopedia
Lactarius aspideoides, commonly known as the bright yellow milkcap, is a species of fungus
in the Russulaceae
family. Distinctive characteristics of the fruit body
include the sticky, pale yellow cap
, and the abundant latex
that stains the mushroom tissue lilac
. It is found in North America.
in 1907. She found the fungus while collecting in Newfane, Vermont
. Lactarius aspideoides is classified in the section Aspideini of the subgenus
Piperites of the genus Lactarius
. Within the Aspideini it is further organized in the stirps Aspideus, along with L. aroostookensis, L. pseudoaspideus, and L. aspideus.
The later homonym Lactarius aspideoides, named by Robert Kühner
in 1975, is an illegitimate name under the rules of the International Code of Botanical Nomenclature. It is now considered synonymous
with Lactarius salicis-reticulatae.
The specific epithet aspideoides means "shield-like". The common name
is the "bright yellow milkcap".
is fleshy and firm, initially convex and umbilicate (with a central depression like a navel), then flattened before becoming funnel-shaped in maturity. Reaching diameters of 3 –, caps are a sulfur-yellow color, with faint zones of narrow concentric rings of lighter and darker yellow tones. The cap is very sticky when wet, and has a thick and persisting gluten. The margin (edge of the cap) is rolled inward and has minute hairs in young specimens. The gills are whitish then cream-colored, spotted with yellow, and packed close together. Sometimes the gills fork next the stem
. Their attachment to the stem is adnate—broadly attached to the stalk slightly above the bottom of the gill, with most of the gill fused to the stem. They are 4 mm (0.15748031496063 in) broad, and stain lilac when the gill tissue has been damaged. The stem is sulfur yellow, often spotted with deeper yellow, sticky when young or wet, and equal in width throughout or abruptly smaller at the base. Its surface is smooth, and it is 3 – long and 10 – thick. The flesh
is whitish, changing to a faint lilac color where exposed to the air. The latex
is white, and has a bitter taste.
In deposit, such as with a spore print
, the spore
s appear pale yellow. Use of a light microscope reveals further details: they are roughly spherical to broadly ellipsoid, measuring 7–9 by 7–8 μm
, and covered with widely spaced, branching broad ridges between 0.5–1.5 μm high. The basidia, the spore-bearing cells, are 35–40 by 8–11 μm, four-spored, and club-shaped.
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. Distinctive characteristics of the fruit body
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...
include the sticky, pale yellow cap
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...
, and the abundant 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,...
that stains the mushroom tissue lilac
Lilac (color)
Lilac is a color that is a pale tone of violet that is a representation of the average color of most lilac flowers. It might also be described as light purple. The colors of some lilac flowers may be equivalent to the colors shown below as pale lilac, rich lilac, or deep lilac...
. It is found in North America.
Taxonomy
The species was first described scientifically by Gertrude Simmons BurlinghamGertrude Simmons Burlingham
Gertrude Simmons Burlingham was an early 20th century mycologist best known for her work on American Russula and Lactarius and pioneering the use of microscopic spore features and iodine staining for species identification...
in 1907. She found the fungus while collecting in Newfane, Vermont
Newfane, Vermont
Newfane is the shire town of Windham County, Vermont, United States. The population was 1,680 at the 2000 census. The town includes the villages of Newfane and Williamsville.-History:...
. Lactarius aspideoides is classified in the section Aspideini 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...
Piperites 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...
. Within the Aspideini it is further organized in the stirps Aspideus, along with L. aroostookensis, L. pseudoaspideus, and L. aspideus.
The later homonym Lactarius aspideoides, named by Robert Kühner
Robert Kühner
Robert Kühner, born Paris 15 March 1903, died Lyon 27 February 1996, was a French mycologist most notable for reviewing many agaric genera.-References:...
in 1975, is an illegitimate name under the rules of the International Code of Botanical Nomenclature. It is now considered synonymous
Synonym (taxonomy)
In scientific nomenclature, a synonym is a scientific name that is or was used for a taxon of organisms that also goes by a different scientific name. For example, Linnaeus was the first to give a scientific name to the Norway spruce, which he called Pinus abies...
with Lactarius salicis-reticulatae.
The specific epithet aspideoides means "shield-like". The common name
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...
is the "bright yellow milkcap".
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 fleshy and firm, initially convex and umbilicate (with a central depression like a navel), then flattened before becoming funnel-shaped in maturity. Reaching diameters of 3 –, caps are a sulfur-yellow color, with faint zones of narrow concentric rings of lighter and darker yellow tones. The cap is very sticky when wet, and has a thick and persisting gluten. The margin (edge of the cap) is rolled inward and has minute hairs in young specimens. The gills are whitish then cream-colored, spotted with yellow, and packed close together. Sometimes the gills fork next the stem
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...
. Their attachment to the stem is adnate—broadly attached to the stalk slightly above the bottom of the gill, with most of the gill fused to the stem. They are 4 mm (0.15748031496063 in) broad, and stain lilac when the gill tissue has been damaged. The stem is sulfur yellow, often spotted with deeper yellow, sticky when young or wet, and equal in width throughout or abruptly smaller at the base. Its surface is smooth, and it is 3 – long and 10 – thick. 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 whitish, changing to a faint lilac color where exposed to the air. 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, and has a bitter taste.
In deposit, such as with a 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...
, the spore
Spore
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 appear pale yellow. Use of a light microscope reveals further details: they are roughly spherical to broadly ellipsoid, measuring 7–9 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...
, and covered with widely spaced, branching broad ridges between 0.5–1.5 μm high. The basidia, the spore-bearing cells, are 35–40 by 8–11 μm, four-spored, and club-shaped.