Cortinarius rubellus

Cortinarius rubellus, commonly known as the Deadly Webcap, is a highly toxic mushroom belonging to the large genus Cortinarius. This species is found predominantly in the Northern Hemisphere, particularly in Europe and North America, within coniferous and mixed forests. It is notorious for containing the potent toxin orellanine, which can cause severe kidney damage and, in some cases, fatal outcomes if ingested.

Description

Cortinarius rubellus features a cap that ranges from 3 to 8 cm in diameter, initially convex before flattening out with age, often with a slight umbo. The cap's color is typically a rusty brown or reddish-brown, sometimes with a more orange hue. The gills are crowded, initially light in color before turning a rusty brown as the spores mature. The stipe (stem) is slender, measuring 4 to 10 cm in height and 0.5 to 1.5 cm in thickness, with a similar coloration to the cap but often paler. A distinctive feature of this species is the presence of a cortina (a web-like veil) in young specimens, which disintegrates with age, leaving a ring zone on the stipe.

Toxicity

The primary toxin present in Cortinarius rubellus is orellanine, which is a nephrotoxin that specifically targets the kidneys. Symptoms of orellanine poisoning may not appear until 2 to 3 days after ingestion, or in some cases, up to three weeks. Initial symptoms include flu-like feelings such as headache, fatigue, nausea, vomiting, and thirst, followed by more severe signs of kidney impairment like decreased urine output and pain in the kidney area. Without prompt and appropriate treatment, ingestion can lead to acute kidney failure and may require dialysis or even lead to death.

Distribution and Habitat

Cortinarius rubellus is primarily found in the Northern Hemisphere, thriving in acidic soils of coniferous and mixed woodlands. It forms mycorrhizal relationships with various tree species, aiding in nutrient exchange. This mushroom is most commonly encountered from late summer to late autumn.

Similar Species

It can be easily confused with other members of the Cortinarius genus, some of which are also toxic. Notably, it resembles Cortinarius speciosissimus, another deadly species, and could be mistaken for edible varieties such as Cortinarius caperatus (the Gypsy mushroom). Proper identification by an expert is crucial before any wild mushroom is consumed.

Conservation

While not considered globally endangered, the population dynamics of Cortinarius rubellus are not well understood, and its presence can indicate the health of forest ecosystems. Conservation efforts focus on preserving its natural habitat and educating the public about the risks of foraging wild mushrooms without proper knowledge.

See Also

• Mushroom poisoning
• Mycorrhiza
• Nephrotoxin

Cortinarius rubellus
Mycological characteristics
	gills on hymenium
	cap is convex
	hymenium is adnate
	stipe has a ring
	ecology is mycorrhizal
	edibility: deadly