Daily Activity of Namib Desert Arthropods in Relation to Climate

Timed traps and visual observations were used to measure the distribution of activity of desert insects, principally tenbrionid beetles, in southwest Africa. Differences between species as regards seasonal and daily cycles were observed. Summer and winter faunas were almost entirely different. Measurements showed how hot and cold extremes may be avoided and how activity may be correlated with microclimatic variables. Daily activity of the tenebrionid Onymacris rugatipennis was bimodal in the summer, unimodal in the winter, and the difference could be correlated with the temperature regime.