Amanita magniverrucata

🏷️ Description

Meet Amanita magniverrucata, a striking and somewhat mysterious member of the Amanitaceae family. Often nicknamed the pine cone amanita or great pine jewel, this large, warty mushroom graces the forest floors of coastal California and Baja California — typically beneath pines and oaks — adding a touch of wild drama to the winter woods.

📖 Taxonomy & Discovery: This impressive species was first formally described in 1982 by American mycologists Harry Delbert Thiers and Joseph Ammirati. Though related to some of the more notorious toxic Amanitas, its edibility remains unknown — and caution is strongly advised. 🍽️🚫

🔎 Identification

Amanita magniverrucata stands out for its massive cap warts that sometimes resemble those of the Sierran puffball, Calvatia sculpta. While there are several lookalike species, the combination of its large, firmly attached warts and distinctive stipe base helps to identify it.

🍄 Cap

• Size: 2 to 8 inches (5 to 20 cm) wide

• Shape: Convex when young, expanding to nearly flat (planoconvex)

• Surface: Moist, white with large, pyramid-shaped warts; these can bruise or darken to cream-buff or buff-brown with age or handling

• Margin: Initially inrolled, becoming incurved to decurved, often with fragments of the partial veil clinging to the edge

• Flesh: White, firm, up to 0.8 inches (2 cm) thick, unchanging when cut

• Odor: Mild when young, turning unpleasant and strong with age — reminiscent of spoiled meat

🌿 Gills

• Attachment: Free to narrowly attached

• Spacing: Close, moderately broad, with 1 to 3 tiers of short gills (lamellulae)

• Color: White to cream, becoming slightly brownish in old age

• Edge: Finely fringed (fimbriate)

📏 Stem

• Size: 2 to 7 inches (5 to 18 cm) long, 0.8 to 1.6 inches (2 to 4 cm) thick

• Structure: Solid, fleshy, typically bulbous at the base with a root-like extension

• Surface: Whitish, dry, striate (lined) at the top, cottony-floccose (hairy) below, sometimes bruising buff-brown to reddish brown

• Ring (Annulus): Thin, fragile, often disappearing as the mushroom matures

• Volva: Present as concentric scaly rings around the base, sometimes vanishing with age

🦠 Spores

• Spore print color: White

• Spores: 9–12 × 6–8 µm, ovoid to ellipsoid, smooth, amyloid (staining blue-black in iodine), with a small apiculus

🌳 Ecology & Habitat

A mycorrhizal species, Amanita magniverrucata forms symbiotic relationships with trees, particularly:

• Monterey pine (Pinus radiata)

• Bishop pine (Pinus muricata)

• Coast live oak (Quercus agrifolia)

It appears solitary to scattered from mid to late winter, favoring the leaf litter of coastal forests in California and Baja California. 🌲🍂

⚠️ Edibility

As with many Amanitas, its edibility is unknown and it may be poisonous. Given the deadly reputation of some of its close relatives, it’s wise to admire this one from a respectful distance. 🍽️☠️

👀 Look-Alikes

1️⃣ Amanita cokeri — generally smaller with less dramatic cap warts and lacking the scaly volva rings at the stipe base.

2️⃣ Calvatia sculpta — similar in appearance but belongs to an entirely different genus.

Photo sources:

Photo 1 - Author: Ken-ichi Ueda (Public Domain)

Photo 2 - Author: Alan Rockefeller (CC BY-SA 4.0)

Photo 3 - Author: Alan Rockefeller (CC BY-SA 4.0)