Pollination and floral insect visitors of non-native Crataegus monogyna Jacq and Crataegus mexicana DC (Rosaceae) in the Eastern Cape Province, South Africa

Abstract Crataegus species (Rosaceae) or hawthorns form dense thickets and displace native vegetation out of their range. In South Africa, monogyna C. mexicana are under surveillance but there is lack information on pollination ecology. Therefore, this study sought to investigate the mechanism potential insect pollinators these plants. Pollinator exclusion experiments were conducted ten plants each near towns Hogsback Seymour respectively, in Eastern Cape Province. Flowers also observed determine diversity distribution visitors throughout day (i.e. morning, mid afternoon). The results showed that capable self cross-pollination. Fruit set from open inflorescences was 40.88 ± 0.08%, significantly higher than bagged inflorences. 48.18 0.03%, those inflorescences. Hymenopterans most frequent flowers while dipterans flowers. insects did not vary with time for plant species. Insect pollination, therefore, plays a significant role fruiting Cape. contribute understanding ecology phenology Africa thus evaluation invasive status.