Amanita jacksonii

🏷️ Description

Amanita jacksonii, fondly known as Jackson's Slender Amanita, Eastern Caesar’s Amanita, or American Slender Caesar, is a dazzling fungal gem of North America. This member of the Amanitaceae family is renowned for its vibrant appearance, culinary value, and fascinating taxonomy.

🧩 Identification Made Easy

• Cap: A radiant red to orange crown, fading from the edges inward with age. Often adorned with a central bump (umbonate), the cap can grow up to 4 inches (10 cm) and boasts lined margins.

• Stem: A slender, yellow stalk adorned with reddish to orange fibrils, crowned with a prominent yellow ring.

• Gills: Crowded, orange-yellow, and free from the stem, with short gills that are neatly truncated.

• Volva: A large, white, sacklike structure at the base—a classic Amanita hallmark.

This mushroom's brilliance ensures it stands out in woodlands, but don’t be fooled: numerous lookalikes exist within section Caesareae and beyond. Notable counterparts include the European Amanita caesarea, North American relatives like Amanita basii and Amanita yema, and even the less similar Amanita flavoconia.

🌎 Where to Find It

Amanita jacksonii thrives in the oak and pine forests of eastern North America, from Quebec to Mexico and as far south as Belize. It favors partial to dappled shade, often forming mycorrhizal associations with forest trees. Look for it in the rich woodlands of the Piedmont region of North Carolina, where it might grow singly or in loose clusters.

🍴 Culinary Status

Amanita jacksonii is a choice edible, celebrated for its mild flavor and pleasing texture. However, its resemblance to toxic species like Amanita muscaria and Amanita phalloides demands extra caution. Always confirm identification before indulging!

🔍 Taxonomy Tidbits

Originally described as Amanita umbonata, this species was reclassified by Canadian mycologist René Pomerleau in 1984. Its taxonomy is part of a complex web of North American Amanitas, making it both a mycological mystery and a culinary treasure.

🔎 Identification

🍄 Cap: Size: 5–12 cm (2–4.7 in) wide. Starts oval, becomes convex with age, often featuring a central bump. Its surface is sticky when fresh, brilliant red or orange, fading to yellow on the edges: The margin becomes lined for about 40–50% of the cap’s radius. Unlike many Amanitas, it lacks warts or patches.

🌿 Gills: Free from the stem or slightly attached. The gills color is vibrant yellow to orange-yellow. Crowded, with frequent short-gills (subtruncate to truncate).

📏 Stem: Dimensions: 8–15 cm (3.1–5.9 in) long, 1–2 cm (0.4–0.8 in) thick. Slightly tapered, yellow with orange to reddish fibers arranged in zones or chevrons. A yellow to orange skirt-like ring and a large, sack-like volva (4–8 cm high, 0.4 cm thick).

🍖 Flesh: Whitish to pale yellow, remaining unchanged when sliced.

👃 Odor: Not distinctive.

🧪 Chemical Reactions: KOH applied to the cap’s surface erases the pigment, turning it yellow.

⚪ Spore Print: White.

🔬 Microscopic Features

• Spores: 7–13 × 6–8 µm, ellipsoid to broadly ellipsoid or subglobose.

• Basidia: 32–38 × 6–8 µm, 4-sterigmate, clamped.

• Pileipellis: An ixocutis of smooth, hyaline elements (2–5 µm wide).

👀 Look-Alikes: Resembles the edible Amanita caesarea (Caesar's mushroom) found in Europe and North Africa. Exercise caution, as it may also be confused with poisonous Amanita species!

🌎 Distribution and Habitat: Amanita jacksonii spans from Québec to Hidalgo, Mexico, reaching as far south as Belize. This versatile mushroom thrives in temperate to subtropical forests, forming mycorrhizal relationships with oaks and pines. It grows alone, scattered, or in groups during summer and fall.

Photo sources:

Photo 1 - Author: Martin Tremblay (CC BY 4.0)

Photo 2 - Author: Karen Szafrajda (CC BY-SA 4.0)

Photo 3 - Author: Nick Abbate (CC BY 4.0)

Photo 4 - Author: Jessica Williams (CC BY 4.0)

Photo 5 - Author: Michael Hinczewski (CC BY 4.0)