Rhynia gwynne-vaughanii was the sporophyte[2] generation of a vascular, axial, free-sporing diplohaplontic embryophytic land plant of the Early Devonian that had anatomical features more advanced than those of the bryophytes.

Rhynia gwynne-vaughanii was a member of a sister group to all other eutracheophytes, including modern vascular plants.

[7] Like those of Aglaophyton major,[8][9] Horneophyton lignieri[10] and Nothia aphylla[11] the gametophytes of Rhynia were dioicous, bearing male and female gametangia (antheridia and archegonia) on different axes.

[13] R. gwynne-vaughanii was named by Kidston and Lang in honour of their late friend and colleague, the botanist David Thomas Gwynne-Vaughan.

In 2004, Crane et al. published a cladogram for the polysporangiophytes, in which Rhynia and the other Rhyniaceae are placed as basal vascular plants (tracheophyes).