Rhizopogon vinicolor is a species complex

Species complex

A species complex is a group of closely related species, where the exact demarcation between species is often unclear or cryptic owing to their recent and usually still incomplete reproductive isolation. Ring species, superspecies and cryptic species complex are example of species complex...

 of ectomycorrhizal fungus

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...

 which forms a mutualistic relationship with the Douglas-fir

Douglas-fir

Douglas-fir is one of the English common names for evergreen coniferous trees of the genus Pseudotsuga in the family Pinaceae. Other common names include Douglas tree, and Oregon pine. There are five species, two in western North America, one in Mexico, and two in eastern Asia...

 (Pseudotsuga spp.). The species was first described scientifically by American mycologist Alexander H. Smith

Alexander H. Smith

Alexander Hanchett Smith was an American mycologist known for his extensive contributions to the taxonomy and phylogeny of the higher fungi, especially the agarics.-Early life:...

 in 1966.

Taxonomy

A number of species of Rhizopogon

Rhizopogon

Rhizopogon is a genus of hypogeous Basidiomycetes. Recent micromorphological and molecular phylogenetic study has established that Rhizopogon is a member of the Boletales, closely related to Suillus. All species of Rhizopogon are ectomycorrhizal and are thought to play an important role in the...

are morphologically

Morphology (biology)

In biology, morphology is a branch of bioscience dealing with the study of the form and structure of organisms and their specific structural features....

 similar and they are collectively known as the R. vinicolor species complex. A phylogenetic investigation of R. vinicolor, R. diabolicus, R. ochraceisporus, R. parvulus and R. versiculosus was published in 2002. It was determined that they separated into two distinct clade

Clade

A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...

s, R. vinicolor and R. versiculosus.

Characteristics

The 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...

 of R. vinicolor are produced underground. They are 10 to 33 mm (0.393700787401575 to 1.3 ) in diameter, rounded or irregularly shaped, of a dirty white colour, later red, and with a few rhizomorphs at the base. The peridium

Peridium

The peridium is the protective layer that encloses a mass of spores in fungi. This outer covering is a distinctive feature of the Gasteromycetes.-Description:...

 is a single layer, becoming wine-red when exposed. The gleba

Gleba

Gleba is the fleshy spore-bearing inner mass of fungi such as the puffball or stinkhorn.The gleba is a solid mass of spores, generated within an enclosed area within the sporocarp. The continuous maturity of the sporogenous cells leave the spores behind as a powdery mass that can be easily blown away...

 is firm and buff coloured, darkening with age, with small labyrinthine locule

Locule

A locule is a small cavity or compartment within an organ or part of an organism ....

s. The trama

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....

 are well-filled with basidiospore

Basidiospore

A basidiospore is a reproductive spore produced by Basidiomycete fungi. Basidiospores typically each contain one haploid nucleus that is the product of meiosis, and they are produced by specialized fungal cells called basidia. In grills under a cap of one common species in the phylum of...

s. These are elliptical to ovoid, 5–9 × 3–5 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...

, do not have a septum

Septum

In anatomy, a septum is a wall, dividing a cavity or structure into smaller ones.-In human anatomy:...

 and are smooth and 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...

. The mycelial cords are few in number or absent altogether.

Ecology

This species forms a mutualistic relationship with coniferous trees. Although some authorities state that R. vinicolor associates exclusively with the Douglas-fir, others mention it being found in association with the ponderosa pine and other pine

Pine

Pines are trees in the genus Pinus ,in the family Pinaceae. They make up the monotypic subfamily Pinoideae. There are about 115 species of pine, although different authorities accept between 105 and 125 species.-Etymology:...

s and fir

Fir

Firs are a genus of 48–55 species of evergreen conifers in the family Pinaceae. They are found through much of North and Central America, Europe, Asia, and North Africa, occurring in mountains over most of the range...

s. The trees benefit from the saprophytic fungus which makes nutrients available by breakdown of the leaf litter and rotting wood, while the fungus benefits from the trees' photosynthetic

Photosynthesis

Photosynthesis is a chemical process that converts carbon dioxide into organic compounds, especially sugars, using the energy from sunlight. Photosynthesis occurs in plants, algae, and many species of bacteria, but not in archaea. Photosynthetic organisms are called photoautotrophs, since they can...

 mechanisms which produce carbohydrate

Carbohydrate

A carbohydrate is an organic compound with the empirical formula ; that is, consists only of carbon, hydrogen, and oxygen, with a hydrogen:oxygen atom ratio of 2:1 . However, there are exceptions to this. One common example would be deoxyribose, a component of DNA, which has the empirical...

s.

The western red-backed vole

Western Red-Backed Vole

The Western Red-Backed Vole is a species of vole in the family Cricetidae. It is found in California and Oregon in the United States and lives mainly in coniferous forest...

 is one of a number of rodents that feed on the fruit bodies. The spores then pass through the vole's gut and are deposited in faecal pellets throughout its extensive burrows. The spores are still viable and this enables the fungus to spread and form associations with uninfected trees. It has been found that if a forest is clear cut and all the dead wood removed, R. vinicolor and other mycorrhiza

Mycorrhiza

A mycorrhiza is a symbiotic association between a fungus and the roots of a vascular plant....

stop fruiting, the vole population dies out and any newly planted trees fail to thrive.