Wallemiales » Basidiomycota genera incertae sedis » Arrasia

Arrasia rostrata

Arrasia rostrata Bernicchia, Gorjón & Nakasone 2011, in Bernicchia et al., Mycotaxon, 118(1), 257-264 (2012).

Etymology: the name rostrata refers to the long refractive rostrum on the basidiospores.

Diagnosis: Basidiomata resupinate, effuse, small, circular to linear patches, becoming confluent, up to 30 × 5 mm, thin, up to 180 μm thick, soft, white, smooth, initially finely farinaceous to subfelty, finally thickly farinaceous; margin abrupt, distinct. Hyphal system monomitic with clamped generative hyphae. Subiculum thin, a dense tissue of hyphae and crystals; subicular hyphae 1.82.3 μm in diam., clamped, moderately branched, walls hyaline, thin, encrusted with hyaline crystals. Subhymenium not observed. Hymenium a palisade of dendrohyphidia, basidia, and indistinct, collapsed hymenial elements obscured by crystals. Dendrohyphidia filamentous, irregular, with short branches near apex, 4062 × 1.52 μm, clamped at base, walls hyaline, thin. Cystidia absent. Basidia obclavate to suburniform at first, then flexuous, narrowly clavate to obclavate, occasionally with a lateral lobe near base, 5090 × 1016 μm, clamped at base, containing resinous globules, often lower part collapsed below a secondary septum, walls hyaline, thin, smooth, (2–)4-sterigmate, sterigmata stout, up to 29 × 5 μm. Basidiospores broadly subfusiform to bi-apiculate, initially distal end obtuse, later developing an extended, thick-walled, refractive rostrum or beak, 2740 × 1015 μm, rostrum 814 × 1.22 μm long, with a distinct, refractive, thick-walled apiculus, containing resinous material, walls hyaline, with distinct walls to slightly thick-walled, smooth, cyanophilous, not reacting in Melzers reagent.

Index Fungorum Number: IF561761