Organism of the day #7

Welwitschia, informally referred to as the living fossil

Welwitschia mirabilis

Welwitschia mirabilis is named after Austrian botanist Fredrich Welwitsch, who was the first European to record the Welwitschia


Vulnerable. The specimens found in Angola are more heavily protected than those located in Namibia, where the only other known populations are found. The reason for this is the leftover landmines from times gone that linger in Angola, which can deter any humans or animals, to say the least. In addition, the growth rates of Welwitschia are slow, like the previously colored Rafflesia. This slow growth rate and lack of external protection make them highly vulnerable to grazing from animals and disease, including some attacks from the fungi kingdom that reduces seed visibility in female Welwitschia cones. Less notable threats include off-road vehicles, the rapid spread of other plants, and overgrazing from zebras and rhinos.

The Welwitschia bears two foliage leaves that crow continuously from a small plant cell from which the fossil grows. The leaves can reach up to 4 meters (13 ft), enough to put the Rafflesia’s huge bloom or the great flying fox’s wingspan to shame. The tips of leaves appear frayed and branch into well-separated strap-shaped sections. The root system of Welwitschia is a complex system of delicate spongy roots with a single woody stem. The roots reach as deep at the leaves are long (from tip to tip). Welwitschia changes minimally with age, which is a strange thing to note about Welwitschia. Welwitschia is an extremely long surviving specimen, some reaching between one and two thousand years of age.

Welwitschia exists exclusively in the African countries of Namibia and Angola, where it grows along the coast of the countries in the Namib desert. Populations exist along two rivers: the Bentiaba River in southern Angola and the Kuiseb River in Namibia. It can be as far inland as 100 km (62 mi) from the coast

The area this plant occupies is extremely arid, the coast recorded as having nearly zero annual inches of rainfall, with the more rainy areas getting 100 mm (3.9 in) between February and April. Because of this, Welwitschia relies on growing above underground water streams or using precipitation from fog. The leaves typically grow at a rate of 8-15 cm a year, which is slow considering the size. But, the Welwitschia relies on what little it has to grow


Welwitschia by its lonesome in the expansive Namib desert