Aspropaxillus candidus

Aspropaxillus candidus

The Autumn Blackthorn or Wood Goat or White Blackthorn (Aspropaxillus candidus (Bres.) M.M.Moser, 1953) is a basidiomycete mushroom belonging to the Tricholomataceae family.

Systematic –
From a systematic point of view it belongs to:
Eukaryota domain,
Fungi Kingdom,
Division Basidiomycota,
Class Agaricomycetes,
Order Agaricales,
Family Tricholomataceae,
Genus Aspropaxillus,
Species A. candidus.
The term is basionym:
– Clitocybe candida Bresadola, 1882.
The terms are synonymous:
– Aspropaxillus candidus (Bres.) Raitlh.;
– Leucopaxillus candidus (Bresadola) Singer.

Etymology –
The term Aspropaxillus comes from the Greek word “άσπρος” (aspros), which means “white”, which refers to the color of the mushroom and, paxillus, a term of Latin origin which means “pickaxe” or “picket”, due to the margin of the hat folded inwards.
The specific epithet candidus derives from candeo, candēre, “to be incandescent”, “to shine”, in turn from the Proto-Indo-European root kand, “to shine”, “to shine”, due to the color of the carpophore.

Geographic Distribution and Habitat –
Aspropaxillus candidus is a mushroom that grows in the autumn period, normally in mixed broad-leaved and coniferous forests in the mountains, forming the so-called “witches’ circles” due to its fruiting in circles.
The plants around which we find it most frequently are: Aspen (Populus tremula), Birch (Betula pubescens) and Spruce (Picea abies).

Recognition –
Aspropaxillus candidus is recognized by having a cap with a diameter varying between 70 and 140 mm, initially convex, then flattened, and finally, with ageing, funnel-shaped; the cuticle is meticulously tomentose, with a color between white and whitish, which with age becomes creamy-white in colour, with a thin, involuted margin, then extended, slightly ribbed.
The hymenium has decurrent, dense lamellae, interspersed with lamellulae, anastomosed, separable from the flesh, white in colour, which become pale-cream-white with age.
The stem is 60-90 mm long; cylindrical in section, or thickened at the bottom, smooth or slightly fibrillose, full, then spongy, white in colour, which darkens with age and upon handling.
The flesh is white, firm, with a more or less floury-spermatic odor and a sweet flavour.
Under the microscope, ellipsoidal, smooth, amyloid spores are identified, (5.80) 5.81-6.60 (7.60) × 4.10-4.40 (4.80) µm, Qm = 1.5. Basidia clavate, tetrasporic, with buckle joints, 42.80-52.38 × 7.14-8.45 µm. Pleurocystidia and cheilocystidia not observed. Pileipellis formed by subparallel hyphae, more or less intertwined, with subcylindrical terminals, up to 8 µm wide. Caulipellis formed by parallel hyphae, with nodular hyphae on the external surface, on which caulocystides 13.70-44.85 × 4.87-6.85 µm are found, mostly in tufts. Buckle joints present throughout the carpophore.

Cultivation –
Aspropaxillus candidus is not a cultivated mushroom.

Customs and Traditions –
Aspropaxillus candidus is a mushroom quite widespread in some countries such as in Italy and Europe in clearings of mountain forests.
Its taxonomic classification begins in 1881 when Bresadola (Ortisé, 14 February 1847 – Trento, 9 June 1929) describes a white, fleshy, funnel-shaped mushroom when ripe, with an involuted and pubescent margin, the gills running along the stem, white and often forked ; the hyaline spores, ellipsoidal, 7 × 3 µm, clavate basidia 30-35 × 6 µm, calling it Clitocybe candida.
However, in 1939 Singer (Schliersee, 23 June 1906 – Chicago, 18 January 1994) asserted that this species has no affinity with the Clitocybe due to the simple fact that its spores are colored dirty purple with Melzer’s reagent; for this reason he recombines the species in Leucopaxillus candidus (Bres.) Singer, indicating, however, in brackets, the genus Aspropaxillus R. Kühner & R. Maire; this genus was created by Kühner & Maire (1934) to include the slightly amyloid spore-bearing species with clitocyboid habitus.
It is only in 1953 that Moser (Innsbruck, 13 March 1924 – Innsbruck, 30 September 2002) recombines Singer’s Leucopaxillus candidus into Aspropaxillus candidus; recombination also supported in more recent times, by Vizzini and others 2012, in a work on the phylogeny of the genus Leucopaxillus.
This species is quite easy to recognize due to its gregarious growth, usually in circles, the white fleshy cap, the involuted margin with short ribs-grooves.
It is a mushroom very similar to Aspropaxillus giganteus (Sowerby) Kühner & Maire [= Leucopaxillus giganteus (Sowerby) Singer], which however is large in size. It can reach 25-30 cm in diameter of the cap, less fleshy, strongly funnel-shaped even in young specimens, slightly involuted margin and with more evident ribs-grooves, especially in mature specimens. Its color is initially cream-white but immediately changes to hazel-cream with ocher shades. It has flesh with a floury-aromatic odor, nauseating in the old. It grows in autumn in mountain meadows or pastures, even at high altitudes, appearing in large groups, with a circular tendency, and growing faster than Aspropaxillus candidus.
Another similar species is Aspropaxillus lepistoides (Maire) Kühner & Maire (= Leucopaxillus lepistoides (Maire) Singer), which however appears very robust and fleshy, with a convex to convex-flattened cap, with an always involuted margin, white in colour, light cream, often with greenish spots.
It also has a very short stem in relation to the diameter of the cap, clubbed with an enlarged base.
Its flesh has a strong aromatic odor. Typical species of the Mediterranean areas, it is gregarious in grassy areas, especially near mastic trees (Pistacia lentiscus L.), in autumn.
Aspropaxillus candidus is a mushroom and an edible mushroom.

Preparation Method –
This mushroom can be prepared in the same way as others, both raw in salads and other dishes and in pastas, risottos or roasted or fried.

Guido Bissanti

Sources
– Wikipedia, the free encyclopedia.
– GBIF, the Global Biodiversity Information Facility.
– Cetto B., 2008. Mushrooms from life, Saturnia, Trento.
– Pignatti S., 1982. Flora d’Italia, Edagricole, Bologna.
– Conti F., Abbate G., Alessandrini A., Blasi C. (ed.), 2005. An annotated checklist of the Italian vascular flora, Palombi Editore.

Photo source:
– https://inaturalist-open-data.s3.amazonaws.com/photos/324746173/original.jpg
– https://upload.wikimedia.org/wikipedia/commons/6/6a/I_funghi_mangerecci_e_velenosi_dell%27Europa_media_%28Tav._XL%29_%288574876716%29.jpg

Attention: Pharmaceutical applications and food uses are indicated for informational purposes only, they do not represent in any way a medical prescription; we therefore decline any responsibility for their use for healing, aesthetic or food purposes.