''Lactifluus'' is one of three genera of

mushroom A mushroom or toadstool is the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground, on soil, or on its food source. ''Toadstool'' generally denotes one poisonous to humans. The standard for the name "mushroom" is t ...

-forming fungi containing species commonly named " milk-caps", the others being ''

Lactarius ''Lactarius'' is a genus of mushroom-producing, ectomycorrhizal fungi, containing several edible species. The species of the genus, commonly known as milk-caps, are characterized by the milky fluid ("latex") they exude when cut or damaged. Like ...

'' and ''

Multifurca ''Multifurca'' is a rare genus of ectomycorrhizal fungi in the family Russulaceae. It was described in 2008, after molecular phylogenetic study had shown that it forms a monophyletic lineage within the family, sister to '' Lactarius''. The gen ...

''. It has been separated from ''

'' based on

molecular phylogenetic Molecular phylogenetics () is the branch of phylogeny that analyzes genetic, hereditary molecular differences, predominantly in DNA sequences, to gain information on an organism's evolutionary relationships. From these analyses, it is possible to ...

evidence but is very similar to that genus. There are roughly 150 known ''Lactifluus'' species, which have a mainly

tropical The tropics are the regions of Earth surrounding the Equator. They are defined in latitude by the Tropic of Cancer in the Northern Hemisphere at N and the Tropic of Capricorn in the Southern Hemisphere at S. The tropics are also referred to ...

distribution but are also found in the

north temperate zone In geography, the temperate climates of Earth occur in the middle latitudes (23.5° to 66.5° N/S of Equator), which span between the tropics and the polar regions of Earth. These zones generally have wider temperature ranges throughout t ...

and

Australasia Australasia is a region that comprises Australia, New Zealand and some neighbouring islands in the Pacific Ocean. The term is used in a number of different contexts, including geopolitically, physiogeographically, philologically, and ecologica ...

. Some of them are

edible mushroom Edible mushrooms are the fleshy and edible fruit bodies of several species of macrofungi (fungi which bear fruiting structures that are large enough to be seen with the naked eye). They can appear either below ground (hypogeous) or above ground ...

Systematics and taxonomy

The genus ''Lactifluus'' was described in 1806 by French naturalist

Henri François Anne de Roussel Henri François Anne de Roussel (11 July 1748, Saint-Bômer-les-Forges – 17 February 1812, Caen) was a French naturalist. He studied humanities and philosophy at the University of Caen, obtaining the rank of "maître ès-arts" in 1767. Afterward ...

, with the type species ''

Lactifluus piperatus ''Lactifluus piperatus'' (synonym ''Lactarius piperatus''), commonly known as the blancaccio, is a semi-edible basidiomycete fungus of the genus ''Lactifluus''. Despite being edible, it is not recommended by some because of its poor taste, thoug ...

''. Later, ''Lactifluus'' was largely considered a

synonym A synonym is a word, morpheme, or phrase that means exactly or nearly the same as another word, morpheme, or phrase in a given language. For example, in the English language, the words ''begin'', ''start'', ''commence'', and ''initiate'' are all ...

of ''Lactarius'', until

work showed in 2008 that ''

'' was not a

monophyletic In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic gro ...

group. In the following, the name ''Lactarius'' was conserved for the biggest of the sub

clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...

s revealed, containing most well-known north temperate species. Thus, the name ''Lactifluus'' could be used for the smaller genus, necessitating only a few name changes, as combinations with ''Lactifluus'' had already been made previously for many temperate species. New combinations have since been proposed for several species formerly classified in ''Lactarius''. A phylogenetics-based revision in 2017 divided the genus in four

subgenera In biology, a subgenus (plural: subgenera) is a taxonomic rank directly below genus. In the International Code of Zoological Nomenclature, a subgeneric name can be used independently or included in a species name, in parentheses, placed between t ...

: ''Lactifluus'', ''Lactariopsis'', ''Gymnocarpi'' and ''Pseudogymnocarpi''. They are further subdivided into

section 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 sign ...

, but not all species are assigned to named sections. Many of these new groups do not correspond to previous subdivisions based mainly on morphology.

Selected species

Lactifluus_sp_G3264_pleurotoid_French_Guiana_cropped

, there are roughly 150 described species, classified in four subgenera. Some notable species are listed below under their respective subgenera. * Subgenus ''Lactifluus'' :* '' Lactifluus corrugis'' – 'corrugated-cap milky' (North America) :* ''

'' – 'peppery milk-cap' (Europe and North America) :* ''

Lactifluus volemus ''Lactifluus volemus'', formerly known as ''Lactarius volemus'', is a species of fungus in the family Russulaceae. It is widely distributed in the northern hemisphere, in temperate regions of Europe, North America and Asia as well as some subt ...

'' – 'weeping milk-cap' or 'voluminous-latex milky' (North and Central America, Europe, Asia) * Subgenus ''Lactariopsis'' :* '' Lactifluus aureifolius'' (tropical Africa) :* ''

Lactifluus deceptivus ''Lactifluus deceptivus'' (Synonym (taxonomy), synonym ''Lactarius deceptivus''), commonly known as the deceiving milkcap, is a common species of fungus in the family Russulaceae. It is found throughout eastern North America on the ground in ...

'' – 'deceiving milk-cap' (North and Central America) :* '' Lactifluus densifolius'' (tropical Africa) :* '' Lactifluus edulis'' (tropical Africa) :* '' Lactifluus heimii'' (tropical Africa) :* ''

Lactifluus vellereus ''Lactifluus vellereus'' (formerly ''Lactarius vellereus''), commonly known as the fleecy milk-cap, is a quite large fungus in the genus ''Lactifluus''. It is one of the two most common milk-caps found with beech trees, with the other being '' L ...

'' – 'fleecy milk-cap' (Europe) * Subgenus ''Gymnocarpi'' :* ''

Lactifluus clarkeae ''Lactifluus clarkeae'', formerly known as ''Lactarius clarkeae'', is a species of mushroom-forming fungus in the family Russulaceae. It is found in Australia and New Zealand in mycorrhizal association with species of ''Nothofagus'' and the fa ...

'' (Australia and New Zealand) * Subgenus ''Pseudogymnocarpi'' :* '' Lactifluus hygrophoroides'' (North America)

Description

''Lactifluus'' closely resembles its lookalike genus ''Lactarius'', with whom it shares the brittle flesh of the

fruit bodies The sporocarp (also known as fruiting body, fruit body or fruitbody) of fungi is a multicellular structure on which spore-producing structures, such as basidia or asci, are borne. The fruitbody is part of the sexual phase of a fungal life cyc ...

and the milk-like latex exuded when bruised. So far,

synapomorphic In phylogenetics, an apomorphy (or derived trait) is a novel character or character state that has evolved from its ancestral form (or plesiomorphy). A synapomorphy is an apomorphy shared by two or more taxa and is therefore hypothesized to have ...

characters for the genus have not been discovered, there are only tendencies that distinguish it from ''Lactarius''. Pleurotoid (laterally stiped) fruitbodies are only known in ''Lactifluus'', while species with closed (angiocarpous) fruitbodies only occur in ''Lactarius''. Microscopically, thick-walled elements in the

pileipellis The pileipellis is the uppermost layer of hyphae in the pileus of a fungal fruit body In botany, a fruit is the seed-bearing structure in flowering plants that is formed from the ovary after flowering. Fruits are the means by which flowe ...

and stipitipellis (

cuticle A cuticle (), or cuticula, is any of a variety of tough but flexible, non-mineral outer coverings of an organism, or parts of an organism, that provide protection. Various types of "cuticle" are non- homologous, differing in their origin, structu ...

of the stipe) and sphaerocytes in the trama of the

lamellae Lamella (plural lamellae) means a small plate or flake in Latin, and in English may refer to: Biology * Lamella (mycology), a papery rib beneath a mushroom cap * Lamella (botany) * Lamella (surface anatomy), a plate-like structure in an animal * ...

are common in ''Lactifluus'', but rare in ''Lactarius'' species.

Edibility

Several species in the genus are

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 mushroo ...

. ''

'' especially is a choice mushroom in the northern temperate region.

References

External links

* {{Taxonbar, from=Q15991147 Russulales genera