Macroscopy – Solitary or in small groups. Cap 2.5-9.5 cm diam., at first conical then convex to plane, with obtuse umbo in the center; pileipellis hygrophanous, ocraceous to brown with sometimes darker center, fibrous, with concentric squamules sometimes persistent; margin rolled, inflected or straight, striated, paler. Stipe 4-10 x 0.6-1.8 cm, cylindrical, subclavate to rarely clavate, orange-brown above ring, whitish below ring; stipitipellis sometimes striated, covered with yellowish flakes below ring, less and less dense towards the base of the stipe; ring fugaceous, fibrillous, submembranous to lannate, fixed, covered with yellowish to light brown flakes. Lamellae dense, white then orange, adnate or subdecurrent lamellulae, dense, white then orange; lamellulae frequent (2-8/Lamella); ridge concolorous. Flesh thin, white to pinkish-white, unchanging. Odour weak, pleasant. Taste bitter. Spore print white.

Microscopy – Spores smooth, hyaline, ellipsoid to broadly ellipsoid, (6.5-)7-8.5(-9.5) x (4-)5-6(-6.5) μm, Q = (1.2-)1.4-1.6(-1.9). Basidia (27-)32-43(-46) x 6.5-)7-8.7(-9.3) μm, narrowly clavate to clavate, 4-spores. Clamp connections present.

Ecology – Saprotrophic, on dead wood; mountain forest.

Note – Some specimens of Armillaria cepistipes can be confused with A. lutea but the latter is characterized by the absence of a bulbous stipe, the presence of squamules over the entire surface of the cap and yellowish flakes on the stipe, characters rarely observed in A. cepistipes.