Aglaophyton

Aglaophyton is an extinct genus of early land plants from the Early Devonian, about 410 million years ago in the Pragian stage. Its best known species, Aglaophyton major, is the sporophyte generation of a free-sporing, pre-vascular plant whose round, smooth stems reached about 6 mm across and branched in forks, ending in thick-walled sporangia that opened by spiral slits. Kidston and Lang read it as an upright plant about 50 cm tall, while Edwards later described it as sprawling with shorter aerial axes of about 15 cm. It was first named Rhynia major in 1920, and in 1986 D.S. Edwards found that its water-conducting tissue was closer to that of moss sporophytes than to true vascular tissue, so he made it a genus of its own. A 2004 cladogram places it as a sister of the vascular plants. It is known only from the Rhynie chert of Aberdeenshire, Scotland, where it grew near a silica-rich hot spring, and it is among the first plants known to have formed a mycorrhizal partnership with fungi.