Micro-arthropods associated with Welwitschia mirabilis in the Namib Desert

Abstract

Significantly more micro-arthropods were found under Welwltschla plants than in unvegetated areas. Densities varied considerably with locality of plant ranging from a mean ± SE of 1710 ± 720 micro-arthropods m-2 in the Northern Najnib 10 145 700 ± 85 930 micro-arthropods m-2 in the southernmost locality. The same taxa were found at all sites and these are also common to North American and Australian deserts. The structure of the micro-arthropod community varied considerably with locality and sex of the plant. Tarsonemld mites were numerically dominant at some sites while Collembofa were dominant at others. Prostlgrnatids were the most abundant group of mites, and mites were generally the most abundant micro-arthropod.