Xylaria longipes  

Stromata 30-50 (-80) x 8-12 (-15) mm, cylindrical to cylindric-clavate, sometimes slightly flattened or irregular, solitary or with several arising from a common base, unbranched or occasionally branched, with rounded apices, ± sessile or with short to long stipes 2-3 mm diam. Young stromatal surface grayish white to brown, becoming black with age, usually with some whitish to brownish scales when young. Stromatal interior white, fibrous. Surface of mature stroma ± smooth to irregularly roughened when fresh, somewhat rugose and sometimes with fine cracks when dry, the ostioles of the ascomata usually visible as minute papillae.
Anamorph: conidiomata absent. Conidiophores short, sparingly branched, forming a dense palisade-like hymenium on young stromata. Conidiogenous cells proliferating sympodially, somewhat inflated, bearing one or several inconspicuous crater-shaped conidial secession scars, sometimes weakly annellate. Conidia (7-) 9-12 (-13) X 4.5-5 (-6) µm, obovoid to ellipsoidal, often with long attenuated basal portions, with a flattened basal scar, smooth, hyaline.
Teleomorph: ascomata perithecia, covering the entire upper surface of the stroma, visible externally as inconspicuous to fairly pronounced hemispherical papillae. Ascomata 400-600 µm diam. and 450-650 µm high, ± globose to almost cylindrical, the neck hardly developed. Peridium 20-30 µm thick, dark olivaceous to ± black, confluent with neighbouring ascomata, composed of tightly intertwined narrow and quite thin-walled hyphae. Interascal tissue of very thin-walled tapering unbranched paraphyses, 1.5-2.5 µm diam. towards the apex and up to 5 µm diam. at the base. Asci 130-180 x 7-9 µm, the spore-bearing part 70-85 µm long, ± cylindrical with a long tapering stipe, with an apical ring ca 2 µm diam. amd 2-4 µm high that is inverted hat-shaped in optical section (the apical part slightly broader than the rest of the ring), blueing in Melzer's iodine reagent, 8-spored. Ascospores (11-) 13-15 (-17) x 5-7 µm, ellipsoid-inequilateral, brown to blackish brown, smooth, aseptate, with a long straight to slightly helicoid germ slit along the entire length of the spore, with a small basal cellular appendage which disappears as spores mature.