Tulostoma thiersii J.E.Wright. (Fig. 144; Pl. XLIX:4) - Mycologia 79 (1). 1987 (in press).
Etym.: Dedicated to the North American mycologist Dr. Harry D. Thiers.
Spore-sac up to 12 mm diam, depressed-globose. Exoperidium distinctly membranous, covered by soil particles, yellowish white when denuded from them. Endoperidium yellowish cream to ochraceous. Mouth circular, slightly projecting. Socket more or less appressed to the stem, membrane simple or double, the inner one denticulated. Gleba ochraceous-ferrugineous . Stem up to 25 x 3 mm, dark reddish brown, Iongitudinally striate, with a thick basal mycelial mat.
Spores brownish under L.M., smooth, subglobose to irregularly ellipsoidal, 3.6-4.6 µm diam; under SEM, they appear almost perfectly smooth, with a rather large hollow apiculus. Capillitium branched, hyaline, septate the threads thick-walled and rather scant lumen, with an apparently crystalline matter deposited on the external wall here and there, moderately swollen at the septa; 2.5-5.2 µm diam, the average width larger than the spore size. Basal mycelium with threads formed by fascicled, distinctly but sparsely clamped, thin-walled, 2.6-5.2 µm diam.
Habitat: soil.
Distribution: North America: United states. South America: Argentina.
Holotype: United States, Texas, Kimble Co., nr Junction, Llano River bottom land, leg. H. D. Thiers 4643, 13.X.1957 (SFSU!; isotype BAFC no 29.470).
