Pollination by monkey beetles (Scarabaeidae : Hopliini): Do color and darkcenters of flowers influence alighting behavior?

Monkey beetles (Scarabaeidae: Rutelinae: Hopliini) visit mostly unscented f lowers with conspicuous dark center patterns that have been suggested to mi mic resting beetles. Field observations in South Africa showed that monkey beetles are the primary pollen vectors of the dark-centered flowers of Ixia dubia Vent. (Iridaceae) and Spiloxene capensis (L.) Garside (Hypoxidaceae) , and the dark-centered flowerheads of Gazania pectinata (Thunb.) Spreng. ( Asteraceae). Monkey beetles used the flowers of these species as mating ren dezvous sites and consequently showed a significant clumped distribution in flowers. We used model flowers approximating the study species to determin e which traits are important for eliciting alighting behavior in monkey bee tles. Contrary to expectations, beetles did not significantly prefer dark-c entered to plain models in 7 of 8 independent experiments, nor did beetles discriminate significantly between plain models and models with male or fem ale beetles glued to their surface. However, beetles did show a strong pref erence for orange over red, yellow, and blue models. The results of this st udy indicate that alighting behavior of monkey beetles is influenced primar ily by flower color rather than flower patterning or presence of other beet les.