FungiPlagiorchiidaHaploporidaeZhouMengWangLiMayTom W.VlasákJosefChenJia-JiaDaiYu-ChengPhylogeny and diversity of Haploporus (Polyporaceae, Basidiomycota)MycoKeys126201954779810.3897/mycokeys.54.34362 Haploporus gilbertsonii MB829649 Meng Zhou, Vlasák&Y.C.Daisp. nov.Figs 6, 7Diagnosis.

Differs from other Haploporus species by its relatively large pores, 2–3 per mm, a dimitic hyphal structure with non-dextrinoid skeletal hyphae, the absence of dendrohyphidia, and wide oblong basidiospores measuring 12–15 × 6–8 µm.

A basidiocarp of Haploporusgilbertsonii (Holotype). Scale bar: 1.0 cm.

Microscopic structures of Haploporusgilbertsonii (Holotype). a Basidiospores b Basidia c Basidioles d Cystidioles e Hyphae from subiculum f Hyphae from trama.

Holotype.

USA. Arizona, Santa Rita Mt., Madera Canyon, on dead tree of Quercus, 20 Nov. 2016, Vlasák Jr. 1611/5-J (Holotype in PRM, isotype in JV and BJFC).

Etymology.

Gilbertsonii (Lat.): in honor of Prof. R.L. Gilbertson, the American mycologist.

Fruitbody.

Basidiocarps annual, resupinate, difficult to separate from the substrate, corky when dry, up to 10 cm long, 8 cm wide and 0.8 mm thick at center. Pore surface pale buff to buff when dry; sterile margin indistinct, very narrow to almost lacking; pores round to angular, 2–3 per mm; dissepiments thick, entire. Subiculum cream, corky, thin, about 0.3 mm thick. Tubes light buff, corky, about 0.5 mm long.

Hyphal structure.

Hyphal system dimitic: generative hyphae bearing clamp connections, hyaline, thin-walled; skeletal hyphae dominant, thick-walled, frequently branched, IKI–, CB–, tissues unchanging in KOH.

Subiculum.

Generative hyphae infrequent, hyaline, thin-walled, occasionally branched, 2–3 µm in diam; skeletal hyphae dominant, hyaline, distinctly thick-walled, frequently branched, interwoven, 1.5–3 µm in diam.

Tubes.

Generative hyphae infrequent, hyaline, thin-walled, occasionally branched, 1–3 µm in diam; skeletal hyphae dominant, distinctly thick-walled, frequently branched, interwoven, 2–4 µm in diam. Cystidia absent; cystidioles present, fusiform, hyaline, thin-walled, 13–23 × 4.5–6 µm. Basidia pear-shaped to barrel-shaped with 4-sterigmata and a basal clamp connection, occasionally with a few large guttules, 21–25 × 10–14 µm; basidioles dominant, similar in shape to basidia, but slightly smaller. Dendrohyphidia absent. Some irregular-shaped crystals present among tube tramal structures.

Spores.

Basidiospores oblong, hyaline, thick-walled, with tuberculate ornamentation, IKI–, CB+, 12–15(–16) × (5.5–)6–8 µm, L = 14.07 µm, W = 6.9 µm, Q = 1.83–2.15 (n = 60/2).

Additional specimen examined (paratype).

USA. Arizona, Chiricahua Mt., Turkey Canyon, on dead tree of Quercus, 5 Sep. 2012, Vlasák Jr. 1209/63-J (JV, dupl. in BJFC).