Cortinarius iodes

🏷️ Description
🔎 Identification
👀 Look-Alikes

🏷️ Description

Meet Cortinarius iodes, also known as the spotted cort or viscid violet cort—a slimy, strikingly purple mushroom with a magical transformation! 🧙‍♂️🍄 Its cap, glistening with slime, starts off in vivid violet but gradually develops yellowish spots and streaks as it matures. Beneath the cap, its gills shift from violet to rusty brown as the spores develop. The stem is also slimy, with hints of purple, though less vibrant than the cap. 🌧️🎨

This mushroom thrives in humid forests, forming mycorrhizal partnerships with oak and other deciduous trees. 🍂🌳 Found in eastern North America, Central America, northern South America, and even parts of Europe and northern Asia, it prefers bog edges, swampy woodlands, and rich leaf litter. 🌍🍁

🛑 Not for eating! While its taste and smell aren’t distinctive, this mushroom isn't recommended for consumption. If you're foraging, beware of lookalikes like Cortinarius iodeoides, which has a bitter cap cuticle.

First described in 1853, C. iodes belongs to the subgenus Myxacium, home to slimy-capped Cortinarius mushrooms. Its name, iodeoides, means "violet-like", a perfect nod to its stunning purple hues. 💜🔬

🔎 Identification

🌍 Habitat & Distribution

Mycorrhizal with oaks 🌳
Grows alone or in groups under hardwoods
Found in humus, leaf litter, and swampy areas 🌿💦
Fruiting from summer to fall (July–November) 🍂
Widespread in eastern North America, also reported in Central & South America, northern Asia, and Serbia, Europe

🎩 Cap

Size: 0.8–2.4 in (2–6 cm)
Shape: Bell-shaped when young, becoming broadly convex or flat
Texture: Slimy when fresh, smooth 🛁
Color: Lilac to deep purple, fading with age and developing yellowish to brownish spots

🍃 Gills

Attachment: Attached to the stem
Spacing: Close to nearly distant
Color: Lilac to violet when young, turning rusty brown with age 🍂
Cortina: Young specimens have a delicate, cobweb-like veil covering the gills 🕸️

🌱 Stem

Size: 1.2–2.8 in (3–7 cm) long, 0.2–0.6 in (0.5–1.5 cm) thick
Shape: Club-shaped when young, becoming more equal with age
Texture: Slimy, smooth
Color: Whitish to silvery lilac, sometimes darker towards the top, with a rusty ring zone 🎨

🥩 Flesh

Color: Whitish to pale lilac inside
Texture: Soft and unchanging when cut
Taste & Odor: No strong smell; taste slightly acetic (cap slime) but not bitter 😬

🔬 Spore Print & Microscopic Features

Spore print: Rusty brown ☁️
Spores: Elliptical, finely roughened, 8–12 × 5–7 μm
Basidia: Four-spored, club-shaped
Hymenium: No cystidia
Cap Cuticle: Distinctive slimy layer with clamped hyphae

🧪 Chemical Reactions

KOH test: Negative or turns pinkish on cap, brownish on flesh

👀 Look-Alikes

1️⃣ Cortinarius iodeoides

Looks identical to C. iodes and grows under hardwoods. Key Difference: Its cap slime tastes bitter (though I don’t recommend licking unknown mushrooms! 🤢). Smaller spores: 7.7–9.3 × 4.6–5.4 μm.

2️⃣ Cortinarius violaceus

Dry, scaly dark purple cap and stem. No slime coat!

3️⃣ Cortinarius traganus

Dry, light purple cap and stem (unlike C. iodes's slimy surface). Strong, unpleasant odor—a dead giveaway!

4️⃣ Cortinarius salor & Cortinarius croceocaeruleus

Both have violet, slimy caps. No yellowish spotting (unlike C. iodes).

5️⃣ Cortinarius oregonensis

Paler lilac cap, with a yellowish or brownish center. Smaller spores: 7–8 × 4–5 μm.

6️⃣ Inocybe lilacina

Dry, silky cap with a prominent umbo (little central bump). Lacks the cortina (web-like veil) and rusty spore print of Cortinarius iodes.

Photo sources:

Photo 1 - Author: Rochelle Davis (CC BY 4.0)