Daedalea americana M.L. Han, Vlasák & B.K. Cui, 2015

Han, Mei-Ling, Vlasák, Josef & Cui, Bao-Kai, 2015, Daedalea americana sp. nov. (Polyporales, Basidiomycota) evidenced by morphological characters and phylogenetic analysis, Phytotaxa 204 (4), pp. 277-286 : 280-283

Daedalea americana M.L. Han, Vlasák & B.K. Cui , sp. nov. ( Figs. 1–2 )

MycoBank: MB 810872

Daedalea americana is characterized by annual and pileate basidiocarps, grayish brown with brown to cinnamon brown band and concentrically zonate pileal surface when fresh, cream to clay-pink pore surface, circular to angular pores (4–5 per mm) and ellipsoid basidiospores measured as 4.0–5.1 × 2.1–3.0 μm.

Type:— USA. Florida: Miami, Matheson Hammock , alt. 1 m, on angiosperm log, 19 April 2009, J Vlasák 0904/20 (holotype, BJFC!; isotype JV!) .

Etymology:— Americana (Lat.) referring to distribution of the species in America.

Basidiocarps: —Basidiocarps annual, pileate, confluent, corky, without odor or taste when fresh, hard corky and light in weight when dry; pileus applanate to slightly concave, semicircular, flabelliform to dimidiate, projecting up to 2.5 cm, 4.5 cm wide and 1.1 cm thick at base; pileal surface grayish brown with brown to cinnamon brown band when fresh, becoming flesh-pink to cream to brown upon drying, glabrous to tuberculate, concentrically zonate and radially streaked; margin cream to pale brown when fresh, becoming cream to clay-pink with age, acute; pore surface cream to clay-pink; sterile margin indistinct; pores circular to angular, 4–5 per mm; dissepiments thin to thick, entire; context cream to clay-buff, corky, up to 9 mm thick; tubes concolorous with pore surface, corky, up to 2 mm long.

Hyphal structure:— Hyphal system trimitic; generative hyphae bearing clamp connections; skeletal hyphae IKI–, CB–; contextual tissues becoming fawn first, then fading into grayish brown in KOH, tramal tissues becoming dark brown firstly, then fading into grayish brown in KOH.

Context: —Generative hyphae infrequent, hyaline, thin-walled, moderately branched, 2–3.5 μm in diam.; skeletal hyphae dominant, hyaline to pale yellowish, thick-walled with a wide to moderate lumen, unbranched, flexuous, 2–4 μm in diam., interwoven; binding hyphae hyaline to pale yellowish, thick-walled with a narrow lumen to subsolid, flexuous, frequently branched, 2–3 μm in diam.

Tubes: —Generative hyphae infrequent, hyaline, thin-walled, moderately branched, 2–3 μm in diam.; skeletal hyphae dominant, hyaline to pale yellowish, thick-walled with a wide to moderate lumen, unbranched, flexuous, 2–3.5 μm in diam., interwoven; binding hyphae hyaline to pale yellowish, thick-walled with a narrow lumen to subsolid, flexuous, frequently branched, 1.5–3 μm in diam. Cystidia absent, sometimes skeletal hyphae penetrated into the hymenium, but not forming typical catahymenium; cystidioles present, fusoid, sometimes with simple septa near to tips, hyaline, thin-walled, 9–17 × 3–3.5 μm. Basidia clavate, bearing four sterigmata and a basal clamp connection, 11–15 × 4–5 μm; basidioles dominant, in shape similar to basidia, but smaller.

Spores: —Basidiospores ellipsoid, tapering at apiculus, hyaline, thin-walled, smooth, IKI–, CB–, 4.0–5.1(–5.5) × (2.0–)2.1–3.0(–3.1) μm, L = 4.55 μm, W = 2.65 μm, Q = 1.70–1.74 (n = 40/2).

Type of rot:—Brown rot.

Additional specimens examined: — USA. Florida: Miami , Matheson Hammock, alt. 1 m, on angiosperm log, 24 December 2003, J Vlasák 0312/24.7-J (paratype, JV!; BJFC!) ; 19 April 2009, J Vlasák 0904/17, J Vlasák 0904/18 (paratypes, JV!) & J Vlasák 0904/19 (paratype, JV!; BJFC!) ; 26 August 2010, J Vlasák 1008/33A (paratype, JV!). Florida: Collier-Seminole State Park , Big Cypress National Preserve, alt. 1 m, on angiosperm, 25 December 2003, J Vlasák 0312/25.8-J (paratype, JV!). Costa Rica. Rincon de la Vieja, Las Pilas Ranger Station, alt. 800 m, on angiosperm log, 1 August 2014, J Vlasák 1408/3 (paratype, JV!; BJFC!) & J Vlasák 1408/23 (paratype, JV!) .

Figures

FIGURE 1. Basidiocarps of Daedelea americana (a JV 0904/19. b JV 0312/25.8-J). Scale bars a–b = 2.5 cm.

FIGURE 2. Microscopic structures of Daedelea americana (JV 0904/20). a Basidiospores. b Basidia and basidioles. c Cystidioles. d Hyphae from trama. e Hyphae from context.