Tulostoma fimbriatum Fr. var. tuberculatum (White) J.E.Wright comb. nov. (Fig.61)
Basionym: T. tuberculatum White, Bull. Torrey bot. Cl. 28 (8): 432, t. 33, figs+ 7-9. 1901.
Etym.: the name probably refers to the spore ornamentation.
Spore-sac up to 15 mm diam. Exoperidium a hyphal layer agglutinated with sand grains, but persisting at the base. Endoperidium not smooth, but areolated, ochraceous cream with yellowish tints. Mouth fibrillose-fimbriate. Socket inconspicuous, separated from the stem. Gleba ochraceous. Stem up to 50 x 3 mm, light-coloured, substriate.
Spores coloured, subglobose to ellipsoid, minutely punctate under L.M. with an oil-immersion objective, 5.3-7 Âµm diam. Under SEM the ornamentation appears formed by small, even verrucae, some almost squamiform, appressed and hardly at all anastomosed. Capillitium slightly yellowish, branched, septate; threads thick-walled, with visible to solid lumen, and hardly at all swollen at the coloured, scant, septa; 5.4-9.4 Âµm diam.
Habitat: sandy soil
Distribution: North America: it appears confined to the N, W and Middle United States, although it may sporadically appear in other regions.
Holotype: Canada, British Columbia, leg. Macoun as T. obesum (NY; isotype at BPI).