Amanita cornelii Mehmood, K. Das, Iqbal Hosen, Tulloss, & R.P. Bhatt

MycoBank number: MB 817887 Facesoffungi number: FoF 2946

Etymology: in honor of Cornelis Bas for his major revision of the study of Amanita.

Holotype: CAL 1337

Pileus 40–60 mm wide, initially convex then planoconvex, umbonate, dark brown (8F4–6) over centre, otherwise having brown to greyish-brown (6D3) rather coarse and irregular radial streaks on pallid ground, smooth, tacky, shiny. Pileus context 3–5 mm thick, thinning evenly toward margin, white, unchanging when exposed or bruised. Margin short-striate up to 10 mm, nonappendiculate. Universal veil on pileus absent. Lamellae free, subdistant (7–8 per 10 mm at margin), 3 mm broad, white (1A1) in mass and in side view. Lamellulae scarce, truncate, of at least 2 lengths, unevenly distributed. Stipe 100–120 x 8–12 mm, slightly tapering upward, with white (2A1) ground, densely covered by light brown to gray (6F3–5) fibrils arranged in ‘‘flame’’ or ‘‘zebroid’’ pattern, with fibrils darkening to nearly black where handled. Stipe context white, hollow, unchanging when bruised or exposed. Partial veil absent. Universal veil at stipe base saccate, 33–39 x 18–24 mm, white (1A1–2A1) thick, membranous, persistent. Spore print white. Odor indistinct. Taste not recorded. Basidiospores [50/2/1] (8–)9–11.5 (–13.5) x (7.5–)8–10.5(–13) um (L = 9–10 um; L0 = 9.31 um; W = 8–10 um; W0 = 8.92 um; Q = (1–)1.02–1.10 (–1.25); Q = 1.05–1.11; Q0 = 1.06), hyaline, colourless, thin walled, inamyloid, globose to subglobose, rarely broadly ellipsoid, with uniguttulate contents, apiculus lateral to sublateral 1.5 x 1 um. Basidia (39–)42–51(–57) x (11–)12–14(–15) um, 2- to 4-spored, thin-walled, colourless; sterigmata up to 4 x 1.5 um. Clamp connections not observed at the base of Basidia. Subhymenium wst-near = 52–75 um thick, wst-far = 60–88 um, Basidia arising from small inflated cells (up to 12 x 14 um wide). Lamellae edge sterile; inflated cell clavate or pyriform, 35–50 x 22–31 um, colourless, thin walled; clamp connections not observed Hymenophoral trama bilateral, divergent; wcs = 50–80 um; well rehydrated, filamentous undifferentiated hyphae (3–16) um wide; vascular hyphae 11–15 x 3–4 um wide. Pileipellis 130–195 um thick, in two layers, with gelatinized colorless suprapellis (40–55 um thick), and ungelatinized subpellis (95–130 um thick); ungelatinized filamentous undifferentiated hyphae 2–6 um wide, subradially arranged densely arranged in subpellis, with brown intracellular pigment vascular hyphae 7–10 x  2.8–3.5 um. Pileus trama filamentous, undifferentiated hyphae 2.5–16 um wide, constricted at septa, thin-walled, branching, forming loose open matrix; acrophysalides common up to 120 x 23 um, thin-walled, hyaline, vascular hyphae rare up to 15 x 5 um. Exterior surface of universal veil (on stipe base) filamentous, undifferentiated hyphae 3–12 um wide; inflated cells subclavate (up to 84 x 34 um), narrowly ellipsoid to elongate (e.g. 120 x 18 um). Interior surface of universal veil (on stipe base) filamentous, undifferentiated hyphae 3–9 um wide; inflated cells subglobose to ovoid (up to 127 x 119 um), infrequent. Stipe context longitudinally acrophysalidic; filamentous undifferentiated hyphae (2–9 um wide); acrophysalides dominating, 151–190 x 31–42 um; clamp connections not observed.

Habitat and distribution: Under Quercus sp., in temperate mixed forest dominated by Abies and Quercus.

Material examined: INDIA, Uttarakhand, Rudraprayag District, Baniyakund, 2630 m, N3028.9140 E7910.8540, 14 July 2015, T. Mehmood, TM 15–625 (CAL 1337, holotype); 18 July 2015, ibid. (TM 15–693, paratype). GenBank Number ITS: KX528072.

Notes: The combination of macro- and micromorphological features such as inamyloid spores, saccate volva, absence of a bulb and absence of Basidia clamps place Amanita cornelii in Amanita [subg. Amanita] sect. Vaginatae sensu Yang (Yang 1997). In the field the present species is distinct from other known species of Amanita sect. Vaginatae by its pileus with coarse, irregular, radial, brown streaks. In eastern Asia, Amanita cornelii might be confused with Amanita brunneofuliginea Zhu L. Yang (Yang 1997) (originally described from China); however, the latter has a pileus that is blackish-brown to brownish black over the centre. The latter also differs by lacking coarse, irregular, brown stripes on the pale background on the pileus, bearing a white to dirty white patches of universal veil on the pileus, its having a saccate volva which is dirty white with plentiful pale-leather to orange spots on its outer surface and by its subglobose to broadly ellipsoid basidiospores ‘‘(10–)10.5–13(–14) x (9–)9.5–12(–12.5) um, (Q = (1.04–)1.06–1.24(–1.26); Q0 = 1.13 ± 0.06)’’ (Yang 1997). Amanita lignitincta Zhu L. Yang (Yang 1997) (originally described from China), is somewhat similar to the present taxon with a wood brown to leather brown pileus; but it differs by its slightly depressed pileus, a contrastingly darker ring–like zone at the inner end of its marginal striations, by its larger basidiospores ‘‘(9.5–)10–13(–13.5) x (8.5–)9–12(–13) um’’ (Yang 1997) and by lacking the unusual striping pattern of the present species. Our nrLSU-tree clearly indicates the genetic dissimilarities of Amanita cornelii from six taxa. BLAST search indicates relative closeness (96% identity with 95% query coverage) of A. cornelii to A. friabilis (GenBank Numbers KU248120, KU248119); (96% identity to 96% query coverage) of A. cornelii to A. basiana (GenBank Numbers KP258987); (96% identity with 94% query coverage) of A. cornelii to A. affin. fulva (GenBank Numbers HQ539697); (96% identity with 95% query coverage) of A. cornelii to A. olivaceogrisea (GenBank Numbers KU867877); (95% identity to 95% query coverage) of A. cornelii to A. affin. ceciliae (GenBank Numbers KU139438, KU139439); (97% identity with 95% query coverage) of A. cornelii to A. populiphila (GenBank Numbers KP221314, KP221304). The European A. basiana Tulloss & M. Traverso (Tulloss and Traverso 2000) and A. friabilis (Karst.) Bas (Bas 1974) are easily segregated from the present species because, in those two taxa, hyphae provide extensive and persistent interconnection between the pileipellis and the universal veil (Bas 1974; Tulloss and Traverso 2000, 2001). Moreover, A. friabilis is separated from A. cornelii by its subglobose to elongate spores ‘‘Q = (1.06–)1.13–1.62(–1.89); Q = 1.23–1.43; Q0 = 1.34’’ ( lis); and A. basiana also differs from the present taxon due to its broadly ellipsoid to ellipsoid spores Q = (1.08– )1.13–1.44(–2.34); Q = 1.21–1.33(–1.36); Q0 = 1.27 ( Volval differences also serve to segregate species that could be mistaken for A. ceciliae (European) and A. olivaceogrisea (European) from the present species. It should be noted that many species in eastern Asia, eastern North America and other regions have been mistaken for A. ceciliae in the past. This group have friable volva’s that quickly become gray with age often leaving warts and small patches on the pileus, fragments on the lower stipe, and a white cupulate structure on the stipe’s base (Bas 1984; Tulloss 1994, 2001). Amanita olivaceogrisea also differs from Amanita cornelii by its subglobose to broadly ellipsoid spores showing slightly higher Q values, i.e. Q = (1.03–)1.04–1.14(–1.27); Q = 1.09–1.11; Q0 = 1.10 ( Amanita%20olivaceogrisea). Amanita affin. fulva (North America) possesses an orange-brown pileus that becomes paler at the margin and brown to dark brown in the center, lacks the irregular striping pattern of the present species, and has a white external volva surface that becomes orange-brown to rusty in numerous spots. The matching GenBank Numbers sequence is a nearly perfect match to sequences derived from Newfoundland material presently treated under a provisional name by Tulloss ( ?Amanita%20daimonioctantes). Amanita populiphila Tulloss & Moses (Tulloss and Moses 1995), described from North America differs from the present taxon by an unstriped, white to pale yellowish pileus that takes on rusty stains with time; cream-colored Lamellae having pale orange or pinkish tint; occurrence of plentiful lamellulae and a weakly structured, white volva that tends to change color as the pileus does. Amanita populiphila has only been recorded with species of Populus [cottonwood and aspen] and has subglobose spores with slightly higher Q values than that of the present taxon; Q = (1–)1.04–1.20(–1.61); Q = (1.06–)1.08–1.15(–1.19); Q0 = 1.11. ( Macro- and micromorphology coupled with the LSU-based genetic distances, segregate Amanita cornelii from previously known species of Amanita sect. Vaginatae.

RAxML tree and putative relationships of Amanita subg. Amanita sect. Vaginatae inferred from analysis of LSU sequence data. Bootstrap support values ([50%) obtained from maximum likelihood analysis are shown above or below the branches at the nodes. The new taxa are highlighted in bold and blue font in the tree. GenBank numbers accession numbers are provided after each species name and followed by country of origin. Amanita caesareae (Scop.) Pers. served as the outgroup taxon. The tree is artificial in that it embodies two somewhat distant clusters of taxa associated with the two new taxa by morphology and/or BLAST searches. This results in a compact single figure and, also, in low support for nodes near the tree’s root

Amanita cornelii (CAL 1337, holotype). a–d Fresh basidiomata in the field. e Basidia and basidiole. f, g Lamellae edges cells.
h Elements of universal veil from stipe base. i Basidiospores. Scale bars a, b = 50 mm, e–i = 50 um

Amanita cornelii (CAL 1338, holotype). a Basidiomata. b Lamellae edge cells. c Basidiospores. d Elements of universal veil at stipe base. e Basidia and elements of hymenium and subhymenium. Scale bars a = 10 mm, b–e = 10 um