''Boletellus'' is a

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 ...

fungi A fungus (plural, : fungi or funguses) is any member of the group of Eukaryote, eukaryotic organisms that includes microorganisms such as yeasts and Mold (fungus), molds, as well as the more familiar mushrooms. These organisms are classified ...

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 ...

. The genus has a widespread distribution, especially in subtropical regions, and contains about 50 species. The genus was first described by American mycologist

William Alphonso Murrill William Alphonso Murrill (October 13, 1869 – December 25, 1957) was an American mycologist, known for his contributions to the knowledge of the Agaricales and Polyporaceae. In 1904, he became the assistant Curator at the New York Botanical ...

in 1909. The genus name means "small Boletus".

Description

According to Murrill's definition of the genus, species of ''Boletellus'' have an annual fruit body that grows on wood and a

stem Stem or STEM may refer to: Plant structures * Plant stem, a plant's aboveground axis, made of vascular tissue, off which leaves and flowers hang * Stipe (botany), a stalk to support some other structure * Stipe (mycology), the stem of a mushr ...

that is centrally placed. The cap surface is floccose-verrucose (covered with tufts of hairs or warts) and yellowish. The fruit body

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 ...

is light colored and fleshy. The tubes on the underside of the cap are angular, depressed, yellowish, and covered with a

partial veil In mycology, a partial veil (also called an inner veil, to differentiate it from the "outer", or universal veil) is a temporary structure of tissue found on the fruiting bodies of some basidiomycete fungi, typically agarics. Its role is to isol ...

. The spores of ''Boletellus'' are

oblong An oblong is a non-square rectangle. Oblong may also refer to: Places * Oblong, Illinois, a village in the United States * Oblong Township, Crawford County, Illinois, United States * A strip of land on the New York-Connecticut border in the Un ...

ellipsoid An ellipsoid is a surface that may be obtained from a sphere by deforming it by means of directional scalings, or more generally, of an affine transformation. An ellipsoid is a quadric surface; that is, a surface that may be defined as the ...

, smooth, and rust-colored. The stem is solid (i.e., not hollow), white, and not

reticulate Reticulation is a net-like pattern, arrangement, or structure. Reticulation or Reticulated may refer to: * Reticulation (single-access key), a structure of an identification tree, where there are several possible routes to a correct identificat ...

. Additional characteristics of the genus have been delineated or amended since its original description over 100 years ago: spores have longitudinal ridges or "wings", are

inamyloid In mycology a tissue or feature is said to be amyloid if it has a positive amyloid reaction when subjected to a crude chemical test using iodine as an ingredient of either Melzer's reagent or Lugol's solution, producing a blue to blue-black staini ...

, and rarely dextrinoid (staining deep reddish to reddish brown in

Melzer's reagent Melzer's reagent (also known as Melzer's iodine reagent, Melzer's solution or informally as Melzer's) is a chemical reagent used by mycologists to assist with the identification of fungi, and by phytopathologists for fungi that are plant pathog ...

). Species usually have hymenial

cystidia A cystidium (plural cystidia) is a relatively large cell found on the sporocarp of a basidiomycete (for example, on the surface of a mushroom gill), often between clusters of basidia. Since cystidia have highly varied and distinct shapes that ar ...

present, and

clamp connection A clamp connection is a hook-like structure formed by growing hyphal cells of certain fungi. It is a characteristic feature of Basidiomycetes fungi. It is created to ensure that each cell, or segment of hypha separated by septa (cross walls), rece ...

s are typically absent (with the exception of '' B. fibuliger''). Murrill placed ''

Boletellus ananas ''Boletellus ananas'', commonly known as the pineapple bolete, is a mushroom in the family Boletaceae, and the type species of the genus ''Boletellus''. It is distributed in southeastern North America, northeastern South America, Asia, and Ne ...

'' (formerly ''Boletus ananas'') as the sole and

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen( ...

. Singer's fourth edition (1986) of his ''Agaricales in Modern Taxonomy'' included 33 species, which were classified into

sections Section, Sectioning or Sectioned may refer to: Arts, entertainment and media * Section (music), a complete, but not independent, musical idea * Section (typography), a subdivision, especially of a chapter, in books and documents ** Section sig ...

depending on moisture content, scaliness of the cap or amount of ornamentation on the stem. Although some species of ''Boletellus'' are rated as

edible An edible item is any item that is safe for humans to eat. "Edible" is differentiated from "eatable" because it does not indicate how an item tastes, only whether it is fit to be eaten. Nonpoisonous items found in nature – such as some mushro ...

, none are considered choice.

Similar genera

In general, Boletes usually have smooth spores, but ''Boletellus'', ''

Austroboletus ''Austroboletus'' is a genus of fungi in the family Boletaceae. The widely distributed genus contains 28 species that form mycorrhizal relationships with plants. Taxonomy E. J. H. Corner originally defined ''Austroboletus'' as a subgenus of ' ...

'', ''

Strobilomyces ''Strobilomyces'' is a genus of boletes (mushrooms having a spongy mass of pores under the cap). The only well-known European species is the type species '' S. strobilaceus'' (also named ''S. floccopus''), known in English as "old man of the wood ...

'', and ''

Heimioporus ''Heimioporus'' is a genus of fungi in the family Boletaceae. The genus is widely distributed in tropical and subtropical regions, and contains about 15 species. The genus name of ''Heimioporus'' is in honour of Roger Jean Heim (1900-1979), who ...

'' are exceptions to this. ''Hemioporus'' species have pitted or reticulate spores, ''Strobilomyces'' species have spiny and reticulate spores, and ''Austroboletus'' species have pitted spores, in comparison to the ridged spores of ''Boletellus'' species.

Species

Here is a list of species currently accepted in the genus ''Boletellus'':

References

External links

Boletaceae
a
The New York Botanical Garden
* {{taxonbar , from=Q1845830 Boletales genera