Phylogenomics resolves the deep phylogeny of seed plants and indicates partial convergent or homoplastic evolution between Gnetales and angiosperms

A phylogenomic analysis sampling all 13 living gymnosperm families recovered cycads plus Ginkgo as sister to the remaining extant gymnosperms and Gnetales as sister to Pinaceae; this is an extant-lineage topology hypothesis, not a fossil chronology or a topology for extinct seed plants.

The Gymnospermae atlas root uses a rounded 365–0 Ma total-seed-plant navigation envelope, anchored by Famennian cupulate seeds and living gymnosperm families; it is not the fossil first appearance or crown age of extant Gymnospermae.