The genus Welwitschia are plants with massive woody tissue, fleshy stems, and large tap roots which may attain a diameter of 1.5m. They have only 2 permanent leaves that grow at a rate of 8 - 15 cm per year. They are found only in Africia. They bear both micro- and macrospores on strobili. Fertilization in Welwitschia is special in that tubular processes from the egg grow up toward and connect with the pollen tubes.
Fertilization occurs within the united tube.
Welwitschia plants as old as 1500 years is not uncommon. Ephedra is the only genus in the family Ephedraceae. It is xerophytic, which means it lives in dry areas. They are shrubs with reduced leaves and pointed stems, attaining a height of 3 - 5 m. They are common to the Rio Grande Valley.