Inocybaceae: Inocybe

Inocybe amygdalina (E. Horak) Garrido

Bibliotheca Mycol. 120: 176 (1988)

PILEUS 20-45 mm wide, conical to plano-convex, with or without an obtuse umbo, margin incurved in youth, soon decurved; surface dry and dull, fibrillose, not rimose, distinct velipellis not noticeable; light yellowish brown or blonde (10YR 6/4) over the disc, fulvous or yellowish brown (10YR 5/6) or brownish orange (5C4) towards the margin; context pallid to watery pale brown, several mm thick under the disc, odor like almond extract or marzipan when cut. LAMELLAE adnexed, close, about 34 L, with several tiers of lamellulae, pale brown (10YR 6/3), edges pallid, indistinctly fimbriate, up to 3 mm broad. STIPE 30-57 × 4-5 mm at apex, base slightly bulbous and up to 5-7 mm wide, base swollen or indistinctly marginate to submarginate; upper half satiny pruinose, lower part finely-fibrillose, no cortina observed; white on the upper half, pale brown (10YR 6/3) in areas on the lower part; context pallid with pale brown areas below.

SPORES 7.7-8.8-9.5 ± 0.48 × 5.3-6.1-7.0 ± 0.41 µm, gibbous with mostly 8-10 moderate sized nodules, yellowish brown (n=30/2). BASIDIA 26-34 × 7-9 µm, 4-sterigmate, clavate, hyaline. PLEUROCYSTIDIA 50-56 × 14-16 µm, utriform, ventricose or (broadly) fusiform, necks not well-developed, tapered at the base with a basal pedicel, apices obtuse and crystalliferous, thick-walled, walls 2.0-4.0 µm thick, pale yellow to hyaline. CHEILOCYSTIDIA similar to pleurocystidia, fusiform, ventricose, or lageniform, mixed with hyaline paracystidia. CAULOCYSTIDIA descending entire length of the stipe, 50-70 × 16-18 µm, mixed with cauloparacystidia and a cells intermediate in size and shape; caulocystidia generally larger than pleurocystidia, mostly fusiform to sublageniform or saccate. PILEIPELLIS composed of an epicutis of hyaline, smooth or lightly incrusted hyphae, these 5-10 µm wide; below a distinct pigmented subcutis yellowish brown in mass, hyphae distinctly incrusted, -20 µm wide. CLAMPS present.

HABITAT: On soil in wet sclerophyll, Tasmania, January-February and May. Type reported under Leptospermum scoparium in coastal forests of New Zealand, February (Horak 1977).

SPECIMENS EXAMINED: AUSTRALIA: TASMANIA. On soil in wet sclerophyll, Lower Kermandie, leg. G. Gates & D. Ratkowsky, 12-Feb-2005 (I107, HO); singly on soil along track in wet sclerophyll under Eucalyptus, Acacia dealbata, Pomaderris, Lower Kermandie, leg. G. Gates, 19-May-2010 (PBM3359, TENN066003); Lower Kermandie, leg. G. Gates, 21-Jan-2011 (I146, HO).

COMMENTS: This collection matches the description of Horak (1977) very well in macromorphology, anatomy and other microscopic characters, and ecology (association with ECM Myrtaceae), other than one statement from the protologue that states “Caulocystidia not distinctive”. Tasmanian collections feature distinctive caulocystidia even on the lower part of the stipe. Despite this incongruence, we are prepared to accept that I. amygdalina also occurs in southeast Australia, though genetic data from New Zealand material (type locality) are lacking. This would be the first report of this species from Australia.

In the field in Tasmania, I. amygdalina is best recognized by the conspicuous odor of marzipan or almond extract, especially when the flesh is cut, the fulvous or brownish orange, dry pileus, entirely pruinose stipe with an indistinct bulb, and association with myrtaceous ECM plant associates.

Reference to a collection of this species from Western Australia was made by O.K. Miller (unpublished data) and labeled E0565 (OKM23766, VPI). This collection was made 206 km north of Perth at Mullering Brook along the Brand Highway in association with Eucalyptus, Hypocalymma angustifolium (White Myrtle), and Chamelaucium uncinatum (Geraldton Wax) by O.K. Miller on 30 May 1998. Unfortunately, we cannot verify the status of this collection, but, if accurate, would suggest that I. amygdalina is a widespread species in New Zealand and temperate Australia.


  • Horak E (1977) Fungi Agaricini Novaezelandiae VI. Inocybe (Fr.) Fr. and Astrosporina Schroeter. N.Z. J. Bot. 15: 713-747.