Phenology and floral biology of cansanção nettle (Cnidoscolus urens L., Euphorbiaceae)

Abstract

The phenological patterns and floral biology of Cnidoscolus urens were studied from observations in natural populations in the Bodopitá Mountain, Queimadas, Paraiba, Brazil, between January/2005 and January/2006. We registered data on the floral biology, behavior and frequency of floral visitors and about the intensity and duration of budding, flowering and fruiting. Cnidoscolus urens has phenophases of leaf flushing, flowering and fruiting which are continuous, peaking during the months April and July. The flowers are white and unisexual, with anthesis of 24 hours. The inflorescences have central pistillate flowers, surrounded by staminate flowers. Cnidoscolus urens is self-compatible, without forming fruit apomictic. The flowers are pollinated by hummingbirds, butterflies and hawkmoths. Being a monoecious and protogynous species, the effectiveness of pollinators is very important to allow the flow of pollen between staminate and pistillate flowers.