Hypomyces microspermus Rogerson & Samuels, Mycologia 81: 426, 1989.   

Anamorph: Sepedonium cf. chrysospermu

Teleomorph in nature: Subiculum effuse, yellow(5Y7/10) to grayish yellow(5Y8/2),olive yellow, Munsell 5Y7/8), covering entire surface of hymenium; hymenial hyphae 4-5.5(-9.5) m  in widt, parenchymatous, septate, thick-walled and KOH (-). Perithecia vivid yellow(5Y8/14) to brownish yellow(10YR7/10), ellipsoidal to broadly ellipsoidal, 178-198(-257) ~ (171-)178-205(-224) m, born in groups harf-immersed in the mycelia; papilla conical, (43-)53-73~63-79(-106) m. Asci cylindrical, (64-)65.5-83(-99) ~ 3-5(-5.5) mm, eightspored with a stalk (5.5-)9.5-11(-19) m long, forming a pore at the slightly thick-walled apex. Ascospores hyaline, fusiform, always unequally two-celled, (9-)11.5-13 ~ 3-3.5(-5) m, smooth to verrucose with warts of <0.5 mm in diameter, apiculate but rounded at both ends; apiculi 0-0.5 m long. 

Characteristics in culture: Colonies on MEA, grow rapidly to reach 37-50 mm in diameter. after 7 days at 25oC, floccose, yellow(5Y8/8) to vivid yellow(5Y8/14),orange(10YR8/10), margins dentate, odor moldy, reverse yellow, (5Y8/8) to vivid yellow(5Y8/14). Hyphae are hyaline to pale yellow (5Y9/2), septate, thick-walled, 3-5(-6.5) m.  Conidiophores born from aerial hyphae, semi-macronematous, septate, slightly thick-walled, two to three times branched irregularly, 3-5(-6.5) m wide, forming conidiogenous cells at the apex. Conidiogenous cells born laterally or as a main branch of conidiophores, solitary or in a whorl, hyaline, 27-51(-80) ~ 2.5-3.5(-5) m, lanceolate, gradually tapered to the apex of (1-)2-2.5 m in width. Conidia clusters from the apex of conidiogenous cells, hyaline, aseptate, cylindrical to long ellipsoidal, ellipsoidal, thin-walled, smooth, (7-)9-13(-17) ~ (2-)3-5 m. Chlamydospores produced laterally on the substrate hyphae or terminally at the apex of the branches, yellow(5Y8/8) to vivid yellow(5Y8/14), verrucose, globose, (9.5-)11.0-14.0 m in width.

Habitat: parasitic on Xerocomus spp.

References

Tokiwa T, Okuda T (2009) Japanese species of Hypomyces and their anamorphs IV. Nippon Kingakukai Kaiho 50: 94-103 (in Japanese)

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