Suillus sibiricus
Description
Suillus sibiricus is a fungus of the genus Suillus in the family Suillaceae. It is found in mountains of Europe, North America, and Siberia, strictly associated with several species of pine tree. Due to its specific habitat and rarity in Europe, it has been selected for inclusion in several regional Red Lists. Its fruit bodies are characterized by having slimy caps in wet weather, which can reach diameters of up to 10 cm (3.9 in). Fruitbody boletoid without or with partial veil, and then leaving a ring on the stipe. Cap in most species more or less viscid. Stipe solid.
It is a good edible mushroom, though many people like to remove the cap skin first, especially if they’re being eaten fresh rather than dried.
Common names: Chicken Fat Suillus, Siberian slippery jack,
Mushroom Identification
Ecology
Mycorrhizal with western white pine (Pinus monticola) and limber pine (Pinus flexilis); growing scattered or gregariously; summer and fall; western North America.
Cap
3-10 cm; convex becoming broadly convex or flat, sometimes with a broad central bump; sticky to slimy; dull to bright yellow; smooth or, more commonly, with scattered brownish to reddish-brown fibers, streaks, scales, or patches; usually with partial veil remnants on the margin.
Pore Surface
Yellow becoming brownish yellow; usually bruising pinkish to cinnamon; pores angular and radially arranged, 1-2 mm across; tubes to 1.5 cm deep.
Stem
4-11 cm long; up to 1.5 cm thick; equal; dull to bright yellow underneath brown to reddish-brown glandular dots; sometimes with a fragile ring; staining reddish to purplish brown with maturity or on handling, especially toward the base.
Flesh
Yellow; not staining on exposure, or staining pinkish to reddish.
Chemical Reactions
Ammonia red on cap surface; red on flesh. KOH black on cap surface (sometimes after a red flash); black on flesh. Iron salts negative to grayish on cap surface; grayish to greenish on flesh.
Spore Print
Cinnamon brown.
Microscopic Features
Spores 8-12 x 3.5-4.5 µ; smooth; subfusoid.
History
The species was first described scientifically under the name Ixocomus sibiricus by American mycologist Rolf Singer in 1938, based on material that was collected under Pinus cembra var. sibirica in the Altai Mountains of central Asia.
In 1945, he transferred it to Suillus. Alexander H. Smith called the species Boletus sibiricus in 1949, but this is today considered a synonym. Singer named the subspecies S. sibiricus subsp. helveticus in 1951, based on material collected by Jules Favre from Switzerland in 1945. Roy Watling later considered this a nomen nudum—not published with an adequate description, and therefore failing to qualify as a formal scientific name.
According to Singer's 1986 arrangement, S. sibiricus is classified in the subsection Latiporini of section Suillus in the genus Suillus. Section Suillus includes species with glandular dots on the stem and a partial veil that becomes appendiculate on the cap edge. Characteristics of species in subsection Latiporini include cinnamon-colored spore prints without an olive tinge, and wide pores on the underside of the cap (wider than 1 mm when mature). Other species in the subsection include S. flavidus, S. umbonatus, S. punctatipes, and S. americanus.
A phylogenetic analysis of various eastern Asian and eastern North American disjunct Suillus species revealed that S. sibiricus forms a well-supported clade with S. americanus and S. umbonatus; these relationships are corroborated by a previous analysis (1996), which used a larger sampling of Suillus species to determine taxonomic relationships in the genus. Within this clade, S. umbonatus and U.S. S. sibiricus can be separated from the rest of the group. However, the phylogenetic relationships among the tested isolates determined from different methods of analysis are not always consistent and could not be established with confidence. In general, there is little phylogenetic divergence detected in this clade.
Photo sources:
Photo 1 - Author: Anna Baykalova (anna_ru) (CC BY-SA 3.0)
Photo 2 - Author: Anna Baykalova (anna_ru) (CC BY-SA 3.0)
