Cycads are an ancient gymnosperm lineage distinct from all other living Spermatophytes. They are considered the most primitive living seed plants, but their relationships to other early fossil spermatophytes remain uncertain. The cycads are a unique group of living seed plants lacking axillary buds and axillary branching. In this communication, we proposed at least two distinct earlier lineages of seed plants are recognized, based on the presence or absence of axillary buds: Axillaryospermae and Cycadospermae. Both lineages are mainly distinguished by the presence/absence of axillary buds, which determine a proper mode of branching, which was a key to the evolution of some groups of plants because they enabled the development of structurally and functionally different branch systems, leaves and reproductive structures. To test this new hypothesis a cladistic analysis was made using morphological and anatomical characters. The results of the new interpretation support and explain the diversity of leaves, branching, and architectural patterns in other seed plants. Studying the evolution of shoot systems and leaves in cycads and comparing them to other fossil and extant spermatophytes is crucial for understanding how seed plants have changed and diversified over time.