Abstract The present study describes the behavior of male Emphorini bees in exploiting Convolvulaceae flowers as sleeping-sheltering place. The observations occurred inadvertently during a field study in an Agroforestry System in the Caatinga region, near the banks of the São Francisco River in Petrolina, Pernambuco – NE-Brazil. Males were observed and collected in wilted flowers of Ipomoea carnea (Convolvulaceae) during the evening. The sampling revealed nine Emphorini bees, belonging to three oligolectic species specialized on Convolvulaceae. We propose that the infundibuliform morphology of Ipomoea carnea flowers and the varied timing of anthesis could influence the choice of these flowers as overnight resting places. Furthermore, we endorse the idea present in the literature that males of oligolectic bees generally engage in patrolling flowers utilized by females, thereby enhancing the chances of encountering potential mates, making these flowers rendezvous places. The observation of this behavior highlights the interdependence between bees and plants and raises the possibility that the loss of these flowers could negatively impact bees not only in a nutrition aspect but also regarding shelter and reproduction. sleepingsheltering sleeping sheltering place region Petrolina NEBrazil. NEBrazil NE Brazil. Brazil NE-Brazil (Convolvulaceae evening places Furthermore females mates reproduction

Resumo O presente estudo documenta o comportamento de abelhas machos do grupo Emphorini em explorar flores da família Convolvulaceae como local para dormir e se abrigar. As observações foram realizadas inadvertidamente durante um estudo de campo em um Sistema Agroflorestal na região da Caatinga, próximo às margens do Rio São Francisco, em Petrolina, Pernambuco - Nordeste do Brasil. Machos foram observados e coletados em flores fechadas de Ipomoea carnea (Convolvulaceae) durante o entardecer. Em nossa amostragem, encontramos nove machos da tribo Emphorini, pertencentes a três espécies oligoléticas especializadas em Convolvulaceae. Propomos que a morfologia infundibuliforme das flores de Ipomoea carnea e os diferentes períodos de antese das flores podem influenciar a escolha dessas flores como locais de descanso durante à noite. Além disso, nossos dados endossam a ideia de que machos de abelhas oligoléticas geralmente patrulham flores utilizadas por fêmeas, aumentando assim as chances de encontrar possíveis parceiras, tornando essas flores locais de encontro para acasalamento. O registro desse comportamento destaca a interdependência entre abelhas e plantas e levanta a possibilidade de que a perda dessas flores possa impactar negativamente as abelhas não apenas em relação a sua nutrição, mas também em relação ao abrigo e reprodução. abrigar Caatinga Francisco Petrolina Brasil (Convolvulaceae entardecer amostragem noite disso fêmeas parceiras acasalamento nutrição reprodução

Abstract Cereus jamacaru is a cactus distributed in Northeastern Brazil, with high symbolic value to this region. However, the interaction, behavior and the role of pollinators remains poorly understood. Here, we investigate the reproductive biology, addressing the ecological significance of floral attributes, including details about floral signaling. The study was carried at three areas of the Caatinga, in 2015, 2017 and 2021. We analyzed the floral morphometry, volume and concentration of the nectar, and characterized the colour and scent of flowers. Additionally, we described the pollinator behavior and performed controlled pollination experiments. The ‘Mandacaru’ is self-incompatible, has nocturnal anthesis and the nectar is accumulated as droplets in a long hypanthial tube. The flowers have a reflective pattern with a dark outer surface and a white inner surface. (E)-nerolidol is the major component (87.4%) of its floral perfume. We registered the sphingid moth Cocytius antaeus visiting the flowers. The floral attributes, attractants and rewards drives to a sphingophily, and the pollination treatments showed the dependence to fruit set by C. antaeus, the pollinator registered. In this case, if the apparent lack of pollinator diversity encompasses its entire range, the loss of the hawkmoth could severely impact the reproductive success of the cactus. Brazil region However interaction understood Here biology attributes signaling Caatinga 2015 201 2021 morphometry Additionally experiments ‘Mandacaru Mandacaru selfincompatible, selfincompatible self incompatible, incompatible self-incompatible tube Enerolidol E nerolidol 87.4% 874 87 4 (87.4% perfume sphingophily C case range 20 202 87.4 8 (87.4 2 87. (87. (87 (8 (

ABSTRACT Plants that occur in arid or semi-arid environments may restrict their flowering to the rainy season to ensure water availability for reproductive functions. However, the exposure of flowers to rainfall can compromise their functionality, such as complex self-pollination mechanisms. We experimentally tested how rainfall exposure affects the sequence of anthesis and reproductive success of Pavonia varians. This species is endemic to the Caatinga, and it has a rainfall-dependent flowering and a specialized mechanism of delayed self-pollination by style curvature. Our results demonstrate that wet flowers have difficulty in distending their petals, and although they maintain the sequence of anthesis, style curvature and corolla closure are delayed. Water exposure also compromised reproductive success by spontaneous self-pollination in bagged flowers but did not prevent fruit set by exposed flowers. These conditions allow cross-pollination in P. varians if rainfall is transient or localized, which is a common condition in the Caatinga. We believe that this type of experimental approach can bring important clues about how reproductive systems respond to abiotic factors, especially in the context of imminent climate change.