Contrasting patterns of foraging behavior in neotropical stingless bees using pollen and honey metabarcoding.

Stingless bees are major flower visitors in the tropics, but their foraging preferences and behavior are still poorly understood. Studying stingless bee interactions with angiosperms is methodologically challenging due to the high tropical plant diversity and inaccessibility of upper canopy flowers in forested habitats. Pollen DNA metabarcoding offers an opportunity of assessing floral visitation efficiently and was applied here to understand stingless bee floral resources spectra and foraging behavior. We analyzed pollen and honey from nests of three distantly related stingless bee species, with different body size and social behavior: Melipona rufiventris, Scaptotrigona postica and Tetragonisca angustula. Simultaneously, we evaluate the local floristic components through seventeen rapid botanical surveys conducted at different distances from the nests. We discovered a broad set of explored floral sources, with 46.3 plant species per bee species in honey samples and 53.67 in pollen samples. Plant families Myrtaceae, Asteraceae, Euphorbiaceae, Melastomataceae and Malpighiaceae dominated the records, indicating stingless bee preferences for abundant resources that flowers of these families provide in the region. Results also reinforce the preference of stingless bees for forest trees, even if only available at long distances. Our high-resolution results encourage future bee-plant studies using pollen and honey metabarcoding in hyper-diverse tropical environments.

Amazonian Brazilian medicinal plants described by C.F.P. von Martius in the 19th century.

ETHNOPHARMACOLOGICAL RELEVANCE: Information regarding the use of beneficial, native Brazilian plants was compiled by European naturalists during the 19th century. The German botanist C.F.P. von Martius was one of the most prominent naturalists and described the use of several Brazilian plants. AIM OF THE STUDY: To present data on Amazonian medicinal plants documented by von Martius in his books. MATERIALS AND METHODS: Data on Amazonian medicinal plants were obtained from three books published by von Martius. Traditional information about these plants was translated from Latin and the cited plant species reorganised according to current taxonomic criteria. Correlated pharmacological studies were obtained from different scientific databases. RESULTS: A total of 92 native medicinal species from the Amazon were recorded in von Martius' books. These accounts described 117 different medical uses for these plants. Several parts of the plants were used, including many exudates. The principal use of the species recorded was the treatment of dermatological problems, followed by gastro-intestinal, urinary and respiratory disorders. Few species were recorded as purgatives and febrifuges, a result that differs from the observations of other naturalists. The efficacy of the recorded traditional uses has been confirmed for the few species that have been subjected to laboratory studies. CONCLUSION: The data recorded by the German naturalist von Martius represent a rich, unexplored source of information about the traditional uses of Brazilian plants.