Boletus rex-veris, commonly known as the spring king bolete, is a basidiomycete

Basidiomycota

Basidiomycota is one of two large phyla that, together with the Ascomycota, comprise the subkingdom Dikarya within the Kingdom Fungi...

 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...

 of the genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 Boletus

Boletus

Boletus is a genus of mushroom, comprising over 100 species. The genus Boletus was originally broadly defined and described by Elias Magnus Fries in 1821, essentially containing all fungi with pores...

found in western North America

North America

North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

. The large, edible fruiting bodies known as mushroom

Mushroom

A mushroom is the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground on soil or on its food source. The standard for the name "mushroom" is the cultivated white button mushroom, Agaricus bisporus; hence the word "mushroom" is most often applied to those fungi that...

s appear under pine trees, generally in May to June. It has a pinkish to brownish cap and its stem is often large and swollen, and the overall colour may have an orange-red tinge. As with other boletes, the size of the fruiting body is variable. Boletus rex-veris is edible, and may be preserved and cooked.

For many years, Boletus rex-veris was considered a subspecies

Subspecies

Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...

 or form

Form (botany)

In botanical nomenclature, a form is one of the "secondary" taxonomic ranks, below that of variety, which in turn is below that of species; it is an infraspecific taxon...

 of the porcini mushroom B. edulis

Boletus edulis

Boletus edulis, commonly known as penny bun, porcino or cep, is a basidiomycete fungus, and the type species of the genus Boletus. Widely distributed in the Northern Hemisphere across Europe, Asia, and North America, it does not occur naturally in the Southern Hemisphere, although it has been...

. In 2008, a taxonomic

Taxonomy

Taxonomy is the science of identifying and naming species, and arranging them into a classification. The field of taxonomy, sometimes referred to as "biological taxonomy", revolves around the description and use of taxonomic units, known as taxa...

 revision of western North American populations of this species was published, formally establishing it as a distinct species, Boletus rex-veris. Phylogenetic

Phylogenetics

In biology, phylogenetics is the study of evolutionary relatedness among groups of organisms , which is discovered through molecular sequencing data and morphological data matrices...

 analysis has shown B. rex-veris as a member of a 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...

, or closely related group, with B. fibrillosus

Boletus fibrillosus

Boletus fibrillosus is a basidiomycete fungus of the genus Boletus found in western North America. The fruiting bodies are found in mixed coastal forests in the fall. The cap is up to 17 cm wide, buff to brown to dark brown in color, and has a wrinkled to finely fibrous texture. The tubes...

, B. pinophilus

Boletus pinophilus

Boletus pinophilus, commonly known as the pine bolete or pinewood king bolete, is a basidiomycete fungus of the genus Boletus found throughout Europe. The large, edible fruiting bodies known as mushrooms appear under pine trees, generally in summer and autumn...

, B. subcaerulescens

Boletus subcaerulescens

Boletus subcaerulescens is a basidiomycete fungus of the genus Boletus found in northeastern North America. The fruiting bodies are found associated with pine and spruce. The cap is up to 18 cm wide, convex to flat, and brown in color. The tubes are yellow and stain blue when bruised, while...

, Gastroboletus subalpinus

Gastroboletus subalpinus

Gastroboletus subalpinus is a species of fungus in the family Boletaceae. The species was first described scientifically in 1969 by American mycologists Harry Delbert Thiers and James M. Trappe. It is found in California and Oregon....

, and B. regineus

Boletus regineus

Boletus regineus, commonly known as the queen bolete, is an edible and highly regarded fungus of the Boletus family that inhabits southwestern North America. It was considered a variant of the similarly edible B. edulis for many years until declared a unique species in 2008. Phylogenetic analysis...

.

Distribution and habitat

Boletus rex-veris is found under pines (Pinus ponderosa, P. contorta subsp. murrayana

Lodgepole Pine

Lodgepole Pine, Pinus contorta, also known as Shore Pine, is a common tree in western North America. Like all pines, it is evergreen.-Subspecies:...

) and firs (Abies concolor and Abies species) at elevations of 3000 to 7000 ft (914.4 to 2,133.6 m). It is often buried under needle duff and fruits from May to June in California. In Oregon it fruits at lower elevations, and its range continues into Washington, Idaho, and British Columbia.

Edibility

The Boletus rex-veris is edible and delicious. It has significant commercial value in areas that it fruits prolifically.