Abstract Floral traits associated with functional groups of pollinators have been largely employed to understand mechanisms of floral diversification. Hymenaea is a monophyletic legume genus widely recognized to being bat-pollinated, with nocturnal anthesis and copious nectar. The most of species has short-paniculate inflorescences, white and robust flowers, congruent with a bat-pollination syndrome. However, other Hymenaea species show a different floral pattern (e.g., long-paniculate inflorescences and smaller flowers) which we report here as being bird pollinated. We examined the floral traits and visitors of Hymenaea oblongifolia var. latifolia and identified evolutionary shifts in floral traits associated with potential pollinators of Hymenaea species. Floral traits of H. oblongifolia var. latifolia differ from those expected for bat-pollinated flowers in species of sect. Hymenaea, and we observed hummingbirds collecting nectar legitimately. Our phylogenetic analysis did not support the monophyly of the taxonomic sections and suggests that bat pollination is ancestral in Hymenaea, with bird pollination evolving later. The transition coupling with shifts in the timing of anthesis and other floral traits. Pollinator-mediated evolutionary divergence hypothesis partially explains the Hymenaea diversification in the Neotropics. It is congruent with those species shifting from traits linked traditionally to bat pollination to hummingbird pollination.

ABSTRACT Peltogyne chrysopis is an arboreal legume endemic to the Atlantic Forest and known only from the state of Bahia, Brazil. Focal observations were made of anthesis, pollen availability, stigma receptivity, nectar production, and the presence of osmophores and UV-reflective pigments for the species. Floral visitors were also observed and classified based on the timing and frequency of their visits and their foraging behavior. The breeding system was inferred from the pollen-ovule ratio and pollen tube growth after pollination treatments. Peltogyne chrysopis was found to be melittophilous, with anthesis occurring from 02h00min to 05h00min, and protogynous and xenogamous, with flower scent emission and pollen release before sunrise. Xenochlora nigrofemorata was the main pollinator, as it effectively collected and transferred pollen grains. Nectar production appears to be a secondary resource to ensure the attraction of a diversity of floral visitors and potential pollinators in the absence of effective pollinators. The results of the present study contribute to understanding the pollination mechanisms of Peltogyne, a genus that has been neglected with regard to its reproductive mechanism, and documents, for the first time, the role of the bee genus Xenochlora in plant pollination.

ABSTRACT We evaluated the vegetative and reproductive phenological patterns of the orchids Cattleya elongata, Cyrtopodium aliciae, Epidendrum orchidiflorum, Epistephium lucidum, and Sobralia liliastrum (Orchidaceae) growing on sandstone outcrops in the Chapada Diamantina Mountains in northeastern Brazil. Phenological events were associated with abiotic factors, leaf longevity, life form, plant growth pattern, and pollination syndrome. Phenological observations were made for 18 months and followed the phenophases of: stem/pseudobulb emission, leaf flush, leaf fall, flowering, immature fruit and mature fruit. Seasonality, synchrony, and correlations between phenophases and environmental variables were tested. The orchid species demonstrated aseasonal vegetative phenologies, except for pseudobulb emission. Reproductive events were seasonal, except for flowering in E. orchidiflorum. There was high flowering overlap between the species pairs S. liliastrum and C. aliciae (dry season) and C. elongata and E. lucidum (rainy season). Dispersal occurred during both the rainy and dry seasons. The vegetative phenophases exhibited low synchrony, and were related to certain morphofunctional characters (stems/pseudobulbs, CAM metabolism). The reproductive phenophases showed high synchrony consistent with the deceit pollination strategy usually associated with the group.

Este trabalho verificou a importância das estratégias fenológicas de Senna cana na atração de visitantes e polinizadores na mata ciliar do rio Lençóis, Chapada Diamantina, Bahia. As observações fenológicas foliares (queda foliar e brotamento) e reprodutivas (botão, flor, fruto imaturo e fruto maduro) foram mensais (18 meses) em 10 indivíduos marcados. Para a biologia floral observou-se: antese, duração das flores, receptividade estigmática, viabilidade polínica, presença de osmóforos e pigmentos que refletem raios ultravioleta. Foram realizados testes de autopolinização manual, espontânea e polinização cruzada. Os visitantes e polinizadores foram determinados observando-se: horário, duração, freqüência das visitas e comportamento de forrageio. Senna cana é uma espécie perenifólia episódica, com eventos reprodutivos sazonais e altamente sincrônicos (floração intermediária no período chuvoso e frutificação longa no período seco). Tais características na floração, somadas à síndrome de melitofilia, configuram importantes estratégias para atração de visitantes florais, dentre os quais Xylocopa frontalis e X. grisescens foram classificadas enquanto potenciais polinizadores. A autoincompatibilidade e o máximo de frutos produzidos após polinização cruzada são mecanismos reprodutivos favorecidos pelas estratégias fenológicas e síndrome de polinização apresentadas pela espécie.

The present work evaluated the importance of the phenological strategies of Senna cana in attracting floral visitors and pollinators in an riparian forest along the Lençóis River, in Chapada Diamantina, Bahia, Brazil. Vegetative and reproductive phenological observations (leaf fall, leaf flushing, flowering, and fruiting) were made on a monthly basis among a group of 10 individuals. The floral biology patterns observed included: anthesis, duration of the flowers, stigma receptivity, pollen viability, and the presence of osmophores and pigments that reflect UV light. Reproductive mechanisms were examined by testing manual and natural self-pollination as well as cross-pollination. Visitors and pollinators were identified, and the time, duration, and frequency of their visitation, as well as their behavior, were noted. Senna cana is an episodic evergreen species showing seasonal and highly synchronous reproductive events (intermediate flowering after a rainy period, and long fruiting during the dry period). These flowering characteristics, in addition to the syndrome of melittophily, are important strategies for attracting floral visitors (including Xylocopa frontalis and X. grisescens, which are potential pollinators). The self-incompatibility and maximization of fruit production through cross-pollination represent reproductive mechanisms favored by the phenological strategies and the pollination syndrome demonstrated by this species.

Neste trabalho é descrita e ilustrada uma espécie nova de Telmatoscopus Eaton (Diptera, Psychodidae) do Brasil. É fornecida uma chave para os machos das espécies Neotropicais de Telmatoscopus.

A new Brazilian species of Telmatoscopus Eaton (Diptera, Psychodidae) is described and illustrated. A key to males of Neotropical species of Telmatoscopus is provided.