Suillus grevillei
Scientific classification
Domain:	Eukaryota
Kingdom:	Fungi
Division:	Basidiomycota
Class:	Agaricomycetes
Order:	Boletales
Family:	Suillaceae
Genus:	Suillus
Species:	S. grevillei
Binomial name
Suillus grevillei (Klotzsch) Singer, 1945
Synonyms
Boletinus grevillei (Klotzsch) Pomerl., 1980 Boletopsis elegans (Schumach.) Henn., 1898 Boletus annularius Bolton, 1792 Boletus clintonianus Peck, 1872 Boletus cortinatus Pers., 1801 Boletus elegans Schumach., 1803 Boletus elegans var. aureus Fr., 1838 Boletus elegans var. cyanescens Velen., 1939 Boletus grevillei Klotzsch, 1832 Cricunopus elegans (Schumach.) P. Karst., 1882 Ixocomus elegans (Schumach.) Singer, 1938 Ixocomus elegans f. badius Singer, 1938 Ixocomus elegans f. elegans (Schumach.) Singer, 1938 Ixocomus elegans f. griseoloporus Singer, 1938 Ixocomus flavus var. elegans (Schumach.) Quél., 1888 Ixocomus grevillei (Klotzsch) Vassilkov, 1955 Suillus clintonianus (Peck) Kuntze, 1898 Suillus elegans (Schumach.) Snell, 1944 Suillus grevillei f. badius (Singer) Singer, 1965 Suillus grevillei var. badius Singer Suillus grevillei var. clintonianus (Peck) Singer, 1951 Suillus grevillei var. grevillei (Klotzsch) Singer, 1945 Suillus grevillei f. grevillei (Klotzsch) Singer, 1945 Suillus grevillei var. proximus (A.H. Sm. & Thiers) W. Klofac, 2013 Suillus proximus A.H. Sm. & Thiers, 1964 Viscipellis elegans (Schumach.) Quél., 1886 Viscipellis flava var. elegans (Schumach.) Quél., 1886

Suillus grevillei Mycological characteristics
	Pores on hymenium
	Cap is convex
	Hymenium is adnate
	Stipe has a ring
	Spore print is ochre
	Ecology is mycorrhizal
	Edibility is edible

Suillus grevillei, commonly known as Greville's bolete, tamarack jack^[1], or larch bolete, is a mycorrhizal mushroom with a tight, brilliantly coloured cap, shiny and wet looking with its mucous slime layer. The hymenium easily separates from the flesh of the cap, with a central stalk that is quite slender. The species has a ring or a tight-fitting annular zone.

Description

Suillus grevillei is a mushroom with a 5–10 cm (2–4 in) cap colored from citrus yellow to burnt orange, that is at first hemispherical, then bell-shaped, and finally flattened. It has a sticky skin, often with veil remnants on the edge,^[2] short tubes of yellow (possibly staining brownish)^[2] which descend down to the bottom of its cylindrical stalk (6–10 x 1–2 cm), which is yellowish above the ring area with streaks of reddish brown below.^[2] The flesh is yellow, staining brown.^[2]

The thin meat has consistency at first but then quickly becomes soft. It has an odor reminiscent of rumpled Pelargonium geranium leaves.

It grows in the soil of mixed forests, not always at the foot of larch (can be quite some distance away) with which it lives in symbiosis. It grows from June until November.

Suillus grevillei is an edible mushroom (without consistency nor flavor) if the slimy cuticle is removed off the cap.^[3] This mucousy skin layer is what is known to cause intestinal issues, as is the case with several other Suillus such as Slippery Jack (S. luteus) or Jill (S. salmonicolor); often considered to be not worth the work.

Its name is derived from Robert Kaye Greville.^[4]

Habitat and distribution

Grows only under larch trees. Widespread in North America and Europe. In Asia, it has been recorded from Taiwan.^[5]

Chemistry

The fungus produces grevillin which is characteristic of this fungus. The genetic and enzymatic basis for atromentin, the precursor to various pulvinic acid-type pigments, has been characterized (an atromentin synthetase by the name, GreA). A cosmid library (31 249 bp in total) has been made from the genome. The estimated gene density based on the cosmid library is 1 per 3900 bp of genomic DNA. The genome has a GC content of 49.8%.