Seventeen species of Talostoma from 92 collections found in Sonora (Mexico) were studied. Four species: Telustoma cyclophorum, T. floridanum, T involucratum, and T. squamosum are new records for Mexico. Most of the studied material was collected in microphyllous desert scrub and tropical thorn forest during summer and winter. Tulostoma fimbriatum was the only species observed in arid, semiarid and temperate areas. Tulostoma floridanum and T. squamositin showed a restricted distribution in tropical deciduous forest. SEM photographs of spore ornamentation are provided.