Agaricus pietatis

Agaricus pietatis L.A. Parra & A. Caballero, Bol. Micol. Famcal 12: 138. 2017

MycoBank MB822543

Taxonomic clasification

phy Basidiomycota

sbp Agaricomycotina

cls Agaricomycetes

sbc Agaricomycetidae

ord Agaricales

fam Agaricaceae

gen Agaricus

sp Agaricus pietatis


Pileus 2-3 cm in diameter, convex, entirely covered with fine radial fibrils that do not dissociate into scales at maturity, purple on the disc, elsewhere tawny with more or less yellowish or orangish dyes slightly lighter towards the margin. Lamellae up to 0.4 cm broad, free, crowded, intercalated with lamellulae, at first whitish, then pale pink, later reddish pink and finally dark brown almost black. Stipe 2.5-3 × 0.3-0.5 cm, claviform or with a slightly bulbous base up to 0,8 cm thick, provided with an annulus in the upper third, with finely fibrillose white surface, above and under the annulus, yellowing with time or when rubbed. Annulus up to 0.1 cm broad, superous, membranous-fibrillose, fragile, simple, whitish or yellowish cream at the margin. Context first white on cutting, then orangish-yellow in the stipe base, with pleasant, anise-like odor, of bitter almonds when rubbed. Spores 4.64-5-5.37 × 3.6-3.8-4 μm, Q = 1.27-1.32-1.43 (n = 30), ellipsoid, brown, without apical pore, usually uniguttulate. Basidia 4-spored, sometimes bi- or trisporic, 14-10 × 7-8 μm, with sterigmata up to 4 μm long, claviform to slightly truncated at the apex. Cheilocystidia very abundant, hyaline, generally simple, from cylindrical to broadly claviform, rarely pyriform or globose, 14-32(-37) × 6-15 μm. Pleurocystidia not observed. Lower surface of the annulus constituted by cylindrical hyphae 3-9 μm wide, not or slightly constricted in the septa, without presence of inflated elements. Pileipellis composed of cylindrical hyphae 2-10 μm wide, the wider the more constricted at septa, hyaline or with diffuse or granular reddish brown pigment in water, and with terminal elements progressively attenuated towards the apex which is rounded. Clamp-connections not observed. Schäffer and KOH reactions positive, orangish-reddish and bright yellow respectively, on the stipe base of dried carpophores. Habitat under Quercus ilex. Holotype: AH47617.


References in our territory
  • Parra LA, Caballero A. 2017. Agaricus pietatis, una especie nueva de Agaricus sect. Minores encontrada en España. Bol. Micol. FAMCAL 12: 137-143.


Specimens in scientific collections

* sequenced material

Reference specimen marked in bold

AC: A. Caballero private herbarium

LAPAG: L.A. Parra private herbarium

Lo: AH-47617*, holotype (isotypes: AC5011 & LAPAG 918); GM-2440


Sequences in public databases obtained from material collected in our territory

AH-47617: MF568546 (ITS)




Photo: A. Caballero, specimen AH-47617 (Holotype)