Pileus: usually absent but occasionally there is a small (ca. 5 mm) reflexed portion of fruitbody which is glabrous, white to ochraceous. Hymenophore: poroid, irregular, (2-3 per mm), white to buff or ochraceous, becoming more yellowish or fulvous on bruising or treatment with KOH. Sterile margin white, around 1-2 mm wide. Tubes: concolorous. Flesh: (trama and context) white and tough. Hyphae: dimitic with simple septate (unclamped) thin-walled generative hyphae later dominated in the mature fruitbody by thicker-walled elements with sparse branching interpreted as either skeletal or binding hyphae. These elements have a distinctive tree-like (arboriform) branching pattern and attenuated whip-like hyphal ends as seen for example in Bovista (capillitium), Dichomitus and Polyporus. Cystidia: none seen. Basidia: lacking basal clamp, clavate, 4- spored, 25 - 32 x 6 - 8 μm. Basidiospores: whitish in prints, Melzers negative, cylindrical, smooth, in water from print 10.2 - 14.1 (16.0) x (4.5) 4.8 - 6.0 μm.