Phenology and floral visitors of Psychotria nuda (Rubiaceae) in an urban fragment of the Atlantic Forest in south Brazil

Abstract

Psychotria nuda is a tree native to Brazil, occurring in the Dense Ombrophylous Forest, which has massive flowering and fruiting, attracting many pollinators and dispersers. This study aimed to know the phenophases of P. nuda and its pollinators, relating them to environmental factors on a temporal scale, with emphasis on flowering, as well as the diversity of pollinators and their phenology. The study area comprises a remnant of forest located in Santa Catarina, southern Brazil. Phenological and pollination observations were performed fortnightly, from July/2016 to July/2017. The results indicated that the peak of senescent leaves, budding, flowering and mature fruits coincided with the hottest and rainy months of the year. Immature fruits persisted almost year-round. There was a low synchrony of phenological activity in the population. Thirteen species of pollinators were recorded, with eight new interactions for P. nuda. The entomophilic syndrome was preponderant, but the pollinator species do not have the same temporal pattern of visitation. It is concluded that P. nuda has shared pollination, predominantly entomophilic, variation of intrapopulational phenological activity and constitutes an important resource for the ornitofauna and entomofauna in the Atlantic Forest since its pollinators use their resources in a non-uniform way.

Keywords: phenological activity, entomophilia, dense ombrophillous forest, animal-plant interaction.