''Rheubarbariboletus'' is a fungal

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial n ...

in the family

Boletaceae The Boletaceae are a family of mushroom-forming fungi, primarily characterised by small pores on the spore-bearing hymenial surface (at the underside of the mushroom), instead of gills as are found in most agarics. Nearly as widely distributed ...

Circumscribed In geometry, the circumscribed circle or circumcircle of a polygon is a circle that passes through all the vertices of the polygon. The center of this circle is called the circumcenter and its radius is called the circumradius. Not every po ...

in 2014, it contains two species found in Europe: ''

Rheubarbariboletus persicolor ''Rheubarbariboletus persicolor'' is a species of bolete fungus. It was originally described in 1996 as ''Xerocomus persicolor'', based on collections made in Italy. The bolete was found in mixed woodland with hop-hornbeam, pine, and oak A ...

'', and the

type Type may refer to: Science and technology Computing * Typing, producing text via a keyboard, typewriter, etc. * Data type, collection of values used for computations. * File type * TYPE (DOS command), a command to display contents of a file. * Ty ...

, '' R. armeniacus''. The generic name is derived from the

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power ...

''rheubarbarum'', meaning "rhubarb", referring to the color of the

flesh Flesh is any aggregation of soft tissues of an organism. Various multicellular organisms have soft tissues that may be called "flesh". In mammals, including humans, ''flesh'' encompasses muscles, fats and other loose connective tissues, but ...

at the base of the stipe. The genus is closely related to '' Xerocomellus'', but differs by having smooth

spores In biology, a spore is a unit of sexual or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores form part of the life cycles of many plants, algae, ...

, the unchanging yellowish to orange-rhubarb coloring of the stipe base, and the distinctive dark-green to black color reaction with

iron sulphate Iron sulfate may refer to: * Ferrous sulfate, Iron(II) sulfate Iron(II) sulfate (British English: iron(II) sulphate) or ferrous sulfate denotes a range of salts with the formula Fe SO4·''x''H2O. These compounds exist most commonly as the hept ...

on both the surface of the cap and on the flesh of the stipe. ''Rheubarbariboletus persicolor'' was originally described in 1996 as ''Xerocomus persicolor'', based on collections made in Italy. The bolete was found in mixed woodland with

hop-hornbeam ''Ostrya'' is a genus of eight to 10 small deciduous trees belonging to the birch family Betulaceae. Common names include hop-hornbeam and hophornbeam. It may also be called ironwood, a name shared with a number of other plants. The genus is nat ...

pine A pine is any conifer tree or shrub in the genus ''Pinus'' () of the family (biology), family Pinaceae. ''Pinus'' is the sole genus in the subfamily Pinoideae. The World Flora Online created by the Royal Botanic Gardens, Kew and Missouri Botanic ...

, and

oak An oak is a tree or shrub in the genus ''Quercus'' (; Latin "oak tree") of the beech family, Fagaceae. There are approximately 500 extant species of oaks. The common name "oak" also appears in the names of species in related genera, notably ''L ...

References

External links

* Boletaceae Boletales genera {{Boletales-stub