Contemporary Circumscription Compared with A Utah Flora 4th ed.

Bio430

Ephedraceae

No differences.

Key Features

This family has a single genus, Ephedra, that is typically a woody shrub, but may be a small tree or vine.  Young stems are green and photosynthetic with shallow longitudinal ridges -- it is somewhat “jointed” in appearance, but very different from Equisetum in that the stems are not hollow and does not pull apart into segments.  Leaves are opposite or whorled, small, and quickly deciduous or at least dry up.  Plants are mostly dioecious; sperm lack flagella, but are unique in gymnosperms in that both sperm fertilize eggs (double fertilization) although one of the newly formed zygotes aborts.