Leucoagaricus barssii

🏷️ Description

Meet Leucoagaricus barssii, also known as the Smoky Dapperling or Gray Parasol — a quietly elegant mushroom with a whitish, shaggy cap and a preference for disturbed grounds and coastal back dunes. Though widespread, it's a rare find in many regions and often mistaken for its more common cousins or even toxic look-alikes. Let’s dive into the fascinating world of this understated fungal beauty. 🌍

🧬 Taxonomy

• Family: Agaricaceae

• First Described As: Lepiota barssii by Sanford Myron Zeller (1934)

• Reclassified As: Leucoagaricus barssii by Else C. Vellinga (2000)

• Interestingly, the type species of the Leucoagaricus genus (L. macrorhizus) is now considered a synonym of L. barssii.

🍽️ Edibility

Leucoagaricus barssii is considered edible in literature, although its rarity and resemblance to toxic species make cautious foraging essential. Its taste is mild and indistinct, and the smell is fresh and pleasantly fungal.

🔎 Identification

🍄 Cap

• Size: 1.57 to 5.12 inches (4 to 13 cm)

• Shape: Hemispherical when young, becoming plano-convex or slightly umbonate

• Surface: Whitish to pale gray-brown center, radially fibrillose to shaggy-scaly with age

• Texture: Dry, thick flesh, unchanging when cut

• Margin: Initially incurved and fringed, later upturned with age

🥩 Flesh

• Color: White, sometimes tinged grey-tan near the cap cuticle

• Reaction: Does not stain or bruise

🍥 Gills

• Attachment: Free from the stem

• Color: White to cream

• Arrangement: Crowded, with 4–5 tiers of lamellulae

• Reaction: Unchanging when bruised

🧱 Stem

• Size: 1.97 to 3.94 inches (5 to 10 cm) long; 0.59 to 0.98 inches (1.5 to 2.5 cm) thick

• Shape: Club-shaped to spindle-shaped, tapering into the substrate (rooted)

• Texture: White with appressed fibrils; browns slowly when handled

• Interior: Stuffed to hollow

• Ring: Large, membranous, white, often superior to medial, or fragmentary in young specimens

🧫 Spore Print

• Color: Creamy white to white

🔬 Microscopic Features

• Spores: 6–9 × 4–5 µm; ellipsoid to ovoid, smooth, dextrinoid (some erratically), no germ pore

• Basidia: 22–25 × 5–6 µm, clavate, 4-sterigmate

• Cheilocystidia: 30–50 × 6–16 µm; clavate, cylindric or subutriform

• Pileipellis: Cutis with smooth, gelatinizing elements 2.5–7.5 µm wide

• Clamp connections: Absent

🌎 Habitat & Distribution

• Ecology: Saprobic — helps break down organic matter.

• Growth Pattern: Solitary, scattered, or in small groups.

• Habitats: Disturbed ground, landscaped areas, roadsides, sparse grassy areas. Frequently seen in agricultural fields, back dunes, and compost heaps.

• Preferred Conditions: Drier soils in general (e.g., sandy urban zones), but prefers moist environments like compost or irrigated fields in the Pacific Northwest.

• Fruiting Season: Late summer to fall.

• Regions: Primarily West Coast of North America (especially Pacific Northwest and California), rare in Europe, also reported in Australia

👀 Look-Alikes

1️⃣ Leucoagaricus leucothites: Bald cap, grows in well-watered lawns, more common

2️⃣ Agaricus xanthodermus & A. californicus: Toxic; distinguished by brown gills at maturity, phenol smell, and yellowing when bruised

3️⃣ Whitish Amanita species (subgenus Lepidella) may look similar, but lack dextrinoid spores and have universal veil remnants

📜 Synonyms

• Lepiota barssii Zeller (1934)

• Leucocoprinus macrorhizus Locquin (1943)

• Lepiota pinguipes A. Pearson (1952)

• Lepiota macrorhiza (Locquin) Kühner & Romagnesi (1953)

• Leucoagaricus macrorhizus Locquin ex E. Horak (1968)

• Leucoagaricus pinguipes (A. Pearson) Bon (1981)

• Leucoagaricus macrorhizus var. pinguipes (A. Pearson) Alessio (1988)

• Leucoagaricus macrorhizus var. pseudocinerascens Bon (1990)

• Leucoagaricus pseudocinerascens (Bon) Bon (1993)

Photo sources:

Photo 1 - Author: Antonio W. Salas (CC BY 4.0)

Photo 2 - Author: Karen Offereins (CC BY 4.0)

Photo 3 - Author: Karen Offereins (CC BY 4.0)

Photo 4 - Author: Antonio W. Salas (CC BY 4.0)