Welwitschia is known as the plant with the longest living leaves. How many leaves does it produce in its centuries-spanning lifetime?

Welwitschia is endemic to the Namib desert. The age of individual plants is difficult to assess, but many plants may be over 1000 (or even 2000) years old. Because Welwitschia only produces a single pair of foliage leaves, the plant was thought by some to be neotenic, consisting essentially of a "giant seedling." However, research showed that its anatomy is not consistent with the giant seedling idea. Instead, the plant is more accurately thought of as achieving its unusual morphology as a result of having "lost its head" (apical meristem) at an early stage.