A plant related to the club mosses, having a dense rosette of long slender leaves, the bases of which contain the spore-producing organs, and occurring typically as a submerged aquatic.
- ‘Liverworts, hornworts, mosses, clubmosses, resurrection plants, quillworts, horsetails, ferns, cycads, ginkgos, conifers, and flowering plants are all plants.’
- ‘First described by Pfeiffer in 1937, and recircumscribed by Brunton et al., I. virginica is a tetraploid quillwort of intermittent woodland streams and low, wet wooded areas of the southeastern Mountains and Piedmont.’
- ‘The other is a quillwort, or Isoetes, which reproduces through male and female spores and thus is considered more closely related to ferns than to flowering plants.’
- ‘This extinct order of giant scale trees includes relatives of the modern quillworts (Isoetes).’