Smilacaceae, the greenbrier family, is a family of
flowering plants. Up to some decades ago the genera now included in family Smilacaceae were often assigned to a more broadly defined family
Liliaceae, but for the past twenty to thirty years most botanists have accepted Smilacaceae as a distinct family. It is considered that the two families evolved around 55 millions years ago during the Early
Paleogene possibly near the boundary between
Paleocene and
Eocene. One characteristic that distinguishes Smilacaceae from most of the other members of the Liliaceae-like Liliales is that it has true vessels in its conducting tissue. Another is that the veins of the leaves, between major veins, are reticulate (net-shaped), rather than parallel as in most
monocots.