Ophioglossales

An order of the Filicinae containing a small group of morphologically distinct ferns. The spores are not borne on the undersurface of the frond but in a separate stalked spike, and unlike all other ferns the fronds do not show *circinate vernation. The order contains three genera: Ophioglossum (adder's tongues) containing about 30 species; Botrychium (moon-worts) containing about 25 species; and Helminthostachys.