Amanita aureofloccosa Bas, Persoonia

Liu, Yuan S., Kumla, Jaturong, Suwannarach, Nakarin, Sysouphanthong, Phongeun & Lumyong, Saisamorn, 2022, Three species of Amanita section Lepidella (Amanitaceae, Agaricales) from northern Thailand, Phytotaxa 570 (1), pp. 16-28 : 23-24

publication ID	https://doi.org/ 10.11646/phytotaxa.570.1.2
DOI	https://doi.org/10.5281/zenodo.7530337
persistent identifier	https://treatment.plazi.org/id/03D2031B-FFAF-CC5C-D385-32FCFE0BDD13
treatment provided by	Plazi
scientific name	Amanita aureofloccosa Bas, Persoonia
status

Treatment

Amanita aureofloccosa Bas, Persoonia View in CoL View at ENA 5: 384 (1969). Figure 1c View FIGURE 1 and 4 View FIGURE 4

Basionym: Lepiota aurea Beeli View in CoL , Bull. Soc. Roy. Bot. Belg. 59: 105. 1927; non Amanita aurea (Beeli) E. J. Gilbert, Iconogr. Mycol. View in CoL 27: 205. 1941 (= Amanitopsis aurea Beeli, Bull. Soc. Roy. Bot. Belg. View in CoL 63: 108. 1931).

Basidiomata large. Pileus 10.5–13.9 cm diam., plano-convex to applanate at maturity; volval remnants on pileus fibrillose to floccose or somewhat pulverulent, vivid yellow (3A8) to yellow (3B8), densely arranged on the disk; margin non-striate, appendiculate; context white (1A1), unchanging. Lamellae free, crowded, white (1A1); lamellulae attenuate with some subtruncate. Stipe 16.2–24.5× 1.8–2.1 cm, cylindrical and slightly tapering upwards, covered by vivid yellow (3A8) to yellow (3B8), floccose and somewhat pulverulent scales; context fistulose, white (1A1); basal part slightly inflated, fibrillose to floccose, light yellow (1A5) to vivid yellow (3A8) volval remnants. Annulus apical, fragile, sub-membranous, vivid yellow (3A8) to yellow (3B8). Odor not recorded.

Lamellar trama bilateral. Mediostratum 10–15 μm wide, composed of abundant sub-cylindrical inflated cells (40–62 × 8–15 μm); filamentous hyphae abundant to dominant, 1–10 μm wide; vascular hyphae scarce. Lateral stratum 15–23 μm wide, composed of abundant clavate to sub-cylindrical inflated cells (20–53 × 8–15 μm), diverging at an angle of ca. 30° to 45° to mediostratum; filamentous hyphae abundant, 2–7 μm wide. Subhymenium 15–25 μm thick, with 1–3 layers of subglobose, or irregular cells, 6–12 × 5–11 μm. Basidia ( Figure 4b View FIGURE 4 ) 33–53 × 11–15 μm, clavate, 4-spored; sterigmata up to 3–4 μm long; basal septa lacking clamps. Basidiospores ( Figure 4a View FIGURE 4 ) [50/2/2] (8) 8.5–10 (10.5) × 7–9 (9.5) μm, avl X avw = 9.1 × 8.4 μm, Q = 1.0–1.19 (1.29) μm, Qm = 1.09 ± 0.07, globose to subglobose, sometimes broadly ellipsoid, amyloid, colorless, guttulate, thin-walled, smooth; apiculus small. Pileipellis composed of radial, thin-walled, yellowish white, filamentous hyphae 3–18 μm wide; vascular hyphae scarce. Volval remnants on pileus ( Figure 4c View FIGURE 4 ) composed of yellowish white, interwoven to repent arranged elements: filamentous hyphae fairly abundant, 2–9 μm wide, thin-walled, branching, anastomosing; inflated cells very abundant to dominant, slenderly clavate to fusiform, 18–165 × 10–40 μm, thin-walled; vascular hyphae scarce. Volval remnants on stipe base is semblable with the structure of volval remnants on pileus, filamentous hyphae scattered, 4–6 μm wide, thin-walled, branching, anastomosing; inflated cells very abundant to dominant, ellipsoid, clavate to sub-cylindrical, 23–200 × 18–35 μm, thin-walled; vascular hyphae scarce. Stipe trama composed of longitudinally arranged, filamentous hyphae, 5–15 μm wide; vascular hyphae scarce. Clamps absent in all parts of basidiomata..

Habitat: Solitary to scattered on soil in subtropical semi-deciduous seasonal forest, tropical deciduous forest, and on the ground along a road, in slightly sun-exposed areas, April to September.

Distribution: This species is currently known in Brazil ( Wartchow et al. 2015), Colombia ( Palacio et al. 2015), Ghana ( Pegler 1968; Wartchow et al. 2015), the Southern Democratic Republic of the Congo ( Bas 1969), and Thailand (this study).

Specimens examined: THAILAND. Chiang Rai Province: Mueang District, N 20°02’29’’, E 99°49’47’’, alt. 435 m, 22 Jun 2020, Phongeun Sysouphanthong , PS-2020-38 (SDBR-STO-2020-PS38, GenBank accession no.: nrLSU = OM 980704 View Materials , ITS = ON000811 View Materials , RPB2 = ON007281 View Materials , and TEF1 View Materials -α = ON007299 View Materials ); GoogleMaps Phongeun Sysouphanthong, PS-2020- 39 (SDBR-STO-2020-PS39, GenBank accession No.: nrLSU = OM 980705 View Materials , ITS = ON000812 View Materials , RPB2 = ON007282 View Materials , and TEF1 View Materials -α = ON007300 View Materials ); GoogleMaps Chiang Mai Province: Mueang District , N 18°47’48’’, E 98°57’11’’, alt. 334 m, 11 Jun 2021, J. Kumla & N. Suwannarach, NK1470 (SDBR-CMUNK1470, GenBank accession no.: ITS = ON695871 View Materials ) GoogleMaps .

Remarks: Morphologically, Amanita aureofloccosa is unique among congeners by having a pulverulent, bright orange-yellow volva remnant on its pileus, a slender stipe covered by orange-yellow floccose scales, a globose to subglobose, amyloid basidiospore and the lacking clamps in all parts of basidiomata. According to the original literature ( Bas 1969), the basidiospores size of A. aureofloccosa was described as 7–8.5 × 6.5–8.5 μm, but Wartcow et al. (2015) re-examined the lectotype (BR2229) and additional material from Ghana (K173243), and amended the basidiospores size to (6.5–) 6.8–10.5 (–10.8) × (6.5–) 6.8–10.2 (–10.5) μm, of which the results are similar to Thai material. Significantly, compared to the materials from other countries, our collections from Thailand have larger basidiomata and basidia.