Amanita aprica
Jans yellow friend
Amanitaceae

Species account author: Ian Gibson.
Extracted from Matchmaker: Mushrooms of the Pacific Northwest.

Introduction to the Macrofungi

Photograph

© Michael Beug     (Photo ID #15237)


Map

E-Flora BC Static Map

Distribution of Amanita aprica
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Species Information

Summary:
Subgenus Amanita. Amanita aprica is a common, spring-fruiting, yellow- to yellow-orange-capped species similar to A. gemmata group and A. muscaria. The cap margin is non-striate or faintly striate; the volva all around the base of the white stem like Amanita ''pantherina'' but with broken concentric bands above this like Amanita muscaria; the white universal veil thinly covering the cap, breaking up partially, or sometimes breaking into floccose warts; and the partial veil forming a fragile membranous ring. It is common in the Pacific Northwest (Lindgren).
Cap:
5-15cm spherical then convex to flat, margin inrolled at first; "bright yellow to yellow-orange, occasionally orange"; "surface usually covered with thin, stretched universal veil", tacky [sticky] when moist, sometimes with marginal remnants and / or with faint striations [Amanita muscaria and A. 'pantherina' are striate at edges], (Lindgren), 5-15cm across, spherical at first, then convex to flat-convex, finally flat with or without depressed disc, margin inrolled at first, slightly uplifted when old; "bright yellow to egg yellow to lemon yellow or bright orangish yellow, occasionally orange (especially over disc), colors sometimes fading and becoming duller after exposure to sun"; bald, tacky to subviscid where cap cuticle exposed at maturity or in moist weather, margin nonstriate or faintly striate (even when old), sometimes bearing fragments of partial veil, the universal veil seen 'as thin appressed downy fibrils or small floccose warts or patches or as a nearly complete floccose-felted to "woolly-felted" covering, or as a nearly complete covering of confluent broadly subpyramidal warts, white to creamy white to yellowish white, detersile', quite commonly remaining attached over much of cap cuticle and becoming thinner as stretched by expanding cap, (Tulloss)
Flesh:
0.6-2cm thick at stem, thinning evenly to less than 0.2cm thick at margin; white, yellow next to cap surface; in stem "white to pale yellow, infrequently with brownish stains in spots on cut surface", (Tulloss)
Gills:
close to subdistant, subgills numerous and truncate [end abruptly]; white to creamy white; gill edges fimbriate [fringed], (Lindgren), free to seceding, with faint decurrent lines on stem apex, close to subdistant, 0.5-1.2cm broad, broadest at midpoint, subgills numerous, "truncate to excavate-truncate"; white to creamy white, unchanging when cut or bruised; edges fimbriate and sometimes uneven, (Tulloss)
Stem:
3.5-9cm x 1.5-3.5cm, usually equal; stuffed to hollow when old; "white to cream, bruising brownish where handled"; pruinose to scurfy below ring, (Lindgren), 3.3-9.1cm x 1.4-3.5cm, usually cylindric, occasionally widening downward, "firmly stuffed with white tissue when young, becoming hollow or partially hollow", bulb often not distinct, merely clavate base of stem (1)1.6-3.4cm x 1.8-4(5)cm, with either rounded or pointed base, sometimes slightly rooting; stem "white to cream to creamy tan, bruising light tan where handled"; "pruinose to flocculose to scurfy below partial veil, flocculence in young specimens easily removed by handling", (Tulloss), VOLVA a cup at the base that has a clean limb where top of cup broken evenly around rim and does not roll out, white to cream, low, close-fitting, margin free, collar is all around the base like Amanita ''pantherina'' but broken concentric bands above this like A. muscaria, (Lindgren, pers. comm.), "low free limb encircling top of bulb, white to cream to creamy tan to pale tan, seldom rolled outward", 0.1-0.3cm thick at about half height of limb, 2.5-3.8cm from base of bulb to highest point on limb, sometimes also as detersile rings on lower stem above limb, also often left in soil or as patches or warts on stem, (Tulloss)
Veil:
superior to median ring, white to cream, membranous yet fragile, skirt-like or collapsing on stem, may be transient, (Lindgren), superior to median ring, white to cream, "felted-membranous at first, soon fragile, skirt-like", sometimes collapsing on stem, sometimes disappearing; universal veil remnants found as the volva and also found on cap, (Tulloss)
Odor:
not distinctive (Tulloss)
Taste:
not distinctive (Tulloss)
Microscopic spores:
spores (8.0) 9.5-13.0(21) x (5.0)6.5-8.5(12.5) microns, (the range of the average value of length / width computed for each specimen = (1.38)1.42-1.62(1.80)), elliptic to elongate, occasionally broadly elliptic, often adaxially flattened, sometimes swollen at one end, occasionally lageniform, infrequently "giant", smooth, inamyloid, colorless, thin-walled, granular to monoguttulate or multiguttulate, (dominantly monoguttulate with additional small granules), apiculus "sublateral, cylindric to truncate-conic, proportionately rather large"; basidia dominantly 4-spored (occasionally 2-spored), 48-70 x 10.0-11.5 microns, projecting up to 12.0-16.0 microns beyond surrounding basidioles, sterigmata up to 5.8 x 4.0 microns, "clamps and proliferated clamps unevenly distributed, infrequent, sometimes small and very thin-walled, requiring persistent search"; clamp connections infrequent in subhymenial base, not observed elsewhere; universal veil on cap "with substantial number of filamentous, undifferentiated hyphae and some vascular hyphae connecting to pileipellis often well into maturity, with gelatinization beginning in hyphae near base simultaneously with some hyphae of pileipellis surface, with elements having subvertical to vertical orientation", (Tulloss)
Spore deposit:
white to creamy white (Tulloss)
Notes:
Collections were examined from BC, WA, OR, CA, (Tulloss). It occurs in ID (Andrew Parker, pers. comm.).
EDIBILITY
one case of poisoning is documented with nausea, vomiting, diarrhea, intestinal cramps, muscle spasms, hallucinations, disorientation, and drowsiness, symptoms similar to those of intoxication with Amanita muscaria, (Tulloss), toxic also to dogs, with symptoms similar to humans, (J. Lindgren, pers. comm.), toxins incompletely known and ingestion should definitely be avoided, as Amanitas may be deadly

Habitat and Range

SIMILAR SPECIES
Amanita muscaria 1) is striate at cap edge, 2) is more often red than orange in the Pacific Northwest, 3) has pyramidal warts with less tendency for a patch in center, 4) has a different volva, 5) grows single or in groups but rarely in clumps (A. aprica is often in clumps), and 6) is less short and stocky, (Lindgren, pers. comm.). Amanita muscaria variants all bear common to plentiful basidial clamps, (Tulloss). Amanita aprica is like A. gemmata group but more robust, with a volva that does not roll out, and the stem more or less equal, (Lindgren, pers. comm.). A. gemmata group has 1) more slender fruitbodies and with cap width reaching only a bit more than half to two-thirds the maximum size of those of A. aprica, 2) cap color yellow-orange, or yellow to pale tan, or nearly white with tan restricted to disc, 3) cap margin distinctly striate, 4) spores proportionately broader than those of A. aprica: the range of the average value of length / width computed for each specimen = 1.29 - 1.36 (or in other calculations 1.42 +/- 0.13 and 1.25-1.27) as opposed to 1.42-1.62 for A. aprica, 5) (following Yang 1997) universal veil on cap "dominated by filamentous, undifferentiated hyphae disordered or with subradial orientation and also including scattered or locally fairly abundant inflated cells", (Tulloss).
Habitat
single to gregarious, most often with Pseudotsuga menziesii (Douglas-fir) in exposed areas, fruits just after morels in spring, (Lindgren), single to gregarious, at 600 - 1850 m elevation, often in sunny locations "such as road cuts, along trails, campgrounds, and other breaks in forest canopy"; occurring with conifers, mainly Pseudotsuga menziesii, less often with Pinus (pine), (Tulloss)