The euphyllophytes are a clade of plants within the tracheophytes (the vascular plants). The group may be treated as an unranked clade,[1] a division under the name Euphyllophyta[2] or a subdivision under the name Euphyllophytina.[3] The euphyllophytes are characterized by the possession of true leaves ("megaphylls"), and comprise one of two major lineages of extant vascular plants.[4] As shown in the cladogram below, the euphyllophytes have a sister relationship to the lycopodiophytes or lycopsids. Unlike the lycopodiophytes, which consist of relatively few presently living or extant taxa, the euphyllophytes comprise the vast majority of vascular plant lineages that have evolved since both groups shared a common ancestor more than 400 million years ago.[4] The euphyllophytes consist of two lineages, the spermatophytes or seed plants such as flowering plants (angiosperms) and gymnosperms (conifers and related groups), and the Polypodiophytes or ferns, as well as a number of extinct fossil groups.[4]
The division of the extant tracheophytes into three monophyletic lineages is supported in multiple molecular studies.[4][5][6] Other researchers argue that phylogenies based solely on molecular data without the inclusion of carefully evaluated fossil data based on whole plant reconstructions, do not necessarily completely and accurately resolve the evolutionary history of groups like the euphyllophytes.[7]
The following cladogram shows a 2004 view of the evolutionary relationships among the taxa described above.[4]
^Kenrick, P. (2000), "The relationships of vascular plants", Philosophical Transactions of the Royal Society B: Biological Sciences, 355 (1398): 847–855, doi:10.1098/rstb.2000.0619, PMC1692788, PMID10905613
^ abcdeKathleen M. Pryer; Eric Schuettpelz; Paul G. Wolf; Harald Schneider; Alan R. Smith; Raymond Cranfill (2004), "Phylogeny and evolution of ferns (monilophytes) with a focus on the early leptosporangiate divergences", American Journal of Botany, 91 (10): 1582–1598, doi:10.3732/ajb.91.10.1582, PMID21652310
^Alan R. Smith; Kathleen M. Pryer; Eric Schuettpelz; Petra Korall; Harald Schneider; Paul G. Wolf (2006), "A classification for extant ferns", Taxon, 55 (3): 705–731, doi:10.2307/25065646, JSTOR25065646
^Kathleen M. Pryer; Harald Schneider; Alan R. Smith; Raymond Cranfill; Paul G. Wolf; Jeffrey S. Hunt; Sedonia D. Sipes (2001), "Horsetails and ferns are a monophyletic group and the closest living relatives to seed plants", Nature, 409 (6820): 618–622, doi:10.1038/35054555, PMID11214320, S2CID4367248
^Rothwell, G.W. & Nixon, K.C. (2006), "How Does the Inclusion of Fossil Data Change Our Conclusions about the Phylogenetic History of Euphyllophytes?", International Journal of Plant Sciences, 167 (3): 737–749, doi:10.1086/503298, S2CID86172890
^Kenrick, Paul; Crane, Peter R. (1997), The Origin and Early Diversification of Land Plants: A Cladistic Study, Washington, D. C.: Smithsonian Institution Press, pp. 339–340, ISBN978-1-56098-730-7
^Crane, P.R.; Herendeen, P.; Friis, E.M. (2004), "Fossils and plant phylogeny", American Journal of Botany, 91 (10): 1683–99, doi:10.3732/ajb.91.10.1683, PMID21652317
^Gonez, P. & Gerrienne, P. (2010a), "A New Definition and a Lectotypification of the Genus Cooksonia Lang 1937", International Journal of Plant Sciences, 171 (2): 199–215, doi:10.1086/648988, S2CID84956576
^Anderson, Anderson & Cleal (2007), "Brief history of the gymnosperms: classification, biodiversity, phytogeography and ecology", Strelitzia, 20, SANBI: 280, ISBN978-1-919976-39-6