Members: 1 genus; 1 species;
Leiosporoceros dussii.
BotanySpores; unusually small, monolete, unornamented; unique strands of Nostoc grow inside the plant parallel with its direction of growth; male plants have not yet been found.
TaxonomyLeiosporoceros has only 1 species; placed in a separate family, order, and class; genetically and morphologically distinct from all other hornworts. Cladistic analysis of genetic data supports a position at the very base of the hornwort clade.