How does the vein pattern of Gnetum leaves differ from the leaves of Ephedra?

The vein patterns of Gnetum and Ephedra differ significantly, reflecting their distinct morphological characteristics:

• Gnetum: The leaves of Gnetum resemble those of angiosperms (flowering plants). They feature a pinnate venation system, which consists of a single midvein with lateral secondary veins extending to the leaf margin, complemented by a complex meshwork of smaller veins.12
• Ephedra: In contrast, the leaves of most Ephedra species are reduced or scalelike. They typically possess only two primary veins, which connect directly to two axial stem vascular bundles.1

These differences in venation serve as definitive morphological characters for identifying these gnetophyte genera.1