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1.
Ann Bot ; 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39223914

RESUMO

BACKGROUND AND AIMS: Flower-visitor interactions comprise a continuum of behaviors, from mutualistic partners to antagonistic visitors. Despite being relatively frequent in natural communities, florivory remains unexplored, especially when comprising abiotic factors, spatio-temporal variations and global environmental changes. Here, we addressed the variation of florivory driven by changes in elevation and temporal flower availability. We expect decreased floral resources as elevation increases -due to environmental constraints- which may affect plant-florivore interactions. Yet, if floral resources decrease but florivores remain constant, then we may expect an increase in florivory with increasing elevation in the community. METHODS: The flowering phenology of plant individuals was recorded in the Neotropical campo rupestre vegetation, in southeastern Brazil. Damages by florivores were recorded in plots at elevations ranging from 823 to 1411 m using two response variables as a proxy for florivory: the proportion of attacked flowers per plant and the proportion of petal removal on single flowers. KEY RESULTS: Flower attack increased with elevation and damages were intensified in species with longer flowering periods. Conversely, longer flowering periods resulted in higher levels of petal removal when decreasing elevation. The temporal availability of flowers affected florivory, with the proportion of attacked flowers being more intense when there are less flowered individuals in the community. Petal removal on single flowers was intensified in plots with a larger number of individuals flowering, and with more species co-flowering. CONCLUSIONS: This study brings one of the broadest records of a commonly neglected interaction of insects feeding on floral structures, quantifying the combined effect of floral display and availability along an elevation gradient in a highly biodiverse mountaintop community. These findings contribute to filling in the gap in the understanding of florivory dynamics, focusing on a tropical mountaintop scenario facing imminent environmental changes and excessive natural resource exploitation.

2.
Bull Entomol Res ; 114(1): 124-133, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38268108

RESUMO

Neotropical cyclocephaline beetles, a diverse group of flower-loving insects, significantly impact natural and agricultural ecosystems. In particular, the genus Cyclocephala, with over 350 species, displays polymorphism and cryptic complexes. Lacking a comprehensive DNA barcoding framework, accessible tools for species differentiation are needed for research in taxonomy, ecology, and crop management. Moreover, cuticular hydrocarbons are believed to be involved in sexual recognition mechanisms in these beetles. In the present study we examined the cuticular chemical profiles of six species from the genus Cyclocephala and two populations of Erioscelis emarginata and assessed their efficiency in population, species, and sex differentiation. Overall we identified 74 compounds in cuticular extracts of the selected taxa. Linear alkanes and unsaturated hydrocarbons were prominent, with ten compounds between them explaining 85.6% of species dissimilarity. Although the cuticular chemical profiles efficiently differentiated all investigated taxa, only C. ohausiana showed significant cuticular profile differences between sexes. Our analysis also revealed two E. emarginata clades within a larger group of 'Cyclocephala' species, but they were not aligned with the two studied populations. Our research underscores the significance of cuticular lipid profiles in distinguishing selected cyclocephaline beetle species and contemplates their potential impact as contact pheromones on sexual segregation and speciation.


Assuntos
Besouros , Animais , Besouros/genética , Ecossistema , Hidrocarbonetos , Feromônios/química , Lipídeos/análise
3.
Ecology ; 104(3): e3900, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36315032

RESUMO

Encounters between flowers and invertebrates are key events for the functioning of tropical forests. Assessing the structure of networks composed of the interactions between those partners leads to a better understanding of ecosystem functioning and the effects of environmental factors on ecological processes. Gathering such data is, however, costly and time-consuming, especially in the highly diverse tropics. We aimed to provide a comprehensive repository of available flower-invertebrate interaction information for the Atlantic Forest, a South American tropical forest domain. Data were obtained from published works and "gray literature," such as theses and dissertations, as well as self-reports by co-authors. The data set has ~18,000 interaction records forming 482 networks, each containing between one and 1061 interaction links. Each network was sampled for about 200 h or less, with few exceptions. A total of 641 plant genera within 136 different families and 39 orders were reported, with the most abundant and rich families being Asteraceae, Fabaceae, and Rubiaceae. Invertebrates interacting with these plants were all arthropods from 10 orders, 129 families, and 581 genera, comprising 2419 morphotypes (including 988 named species). Hymenoptera was the most abundant and diverse order, with at least six times more records than the second-ranked order (Lepidoptera). The complete data set shows Hymenoptera interacting with all plant orders and also shows Diptera, Lepidoptera, Coleoptera, and Hemiptera to be important nodes. Among plants, Asterales and Fabales had the highest number of interactions. The best sampled environment was forest (~8000 records), followed by pastures and crops. Savanna, grasslands, and urban environments (among others) were also reported, indicating a wide range of approaches dedicated to collecting flower-invertebrate interaction data in the Atlantic Forest domain. Nevertheless, most reported data were from forest understory or lower strata, indicating a knowledge gap about flower-invertebrate interactions at the canopy. Also, access to remote regions remains a limitation, generating sampling bias across the geographical range of the Atlantic Forest. Future studies in these continuous and hard-to-access forested areas will yield important new information regarding the interactions between flowers and invertebrates in the Atlantic Forest. There are no copyright restrictions on the data set. Please cite this data paper if the data are used in publications and teaching events.


Assuntos
Himenópteros , Lepidópteros , Humanos , Animais , Ecossistema , Invertebrados , Florestas , Plantas , Flores , Polinização
4.
Curr Zool ; 68(1): 69-79, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35169630

RESUMO

Some types of plant accumulate liquid in their inflorescences creating phytotelmata. These environments protect the flowers against florivory, although they may be colonized by aquatic or semi-aquatic florivorous insect larvae, whose effects on the fitness of the plants remain unclear. We tested the hypothesis of floral antagonism by the occupants of phytotelmata, which predicts that florivory by the occupants of the phytotelmata represents a cost to the female fitness of the plant, reducing its fecundity. We manipulated experimentally the infestation by 3 florivores larvae species occupants of phytotelmata in inflorescences of Heliconia spathocircinata (Heliconiaceae) to test for negative direct trophic effects on the fecundity of the flowering and fruiting bracts. We found that the foraging of the hoverfly (Syrphidae) and moth (Lepidoptera) larvae in the inflorescences contributed to a decline in the fecundity of the plant. While the lepidopteran impacted fecundity when foraging in both flowering and fruiting bracts, the syrphid only affected the fruiting bracts, which indicates that the nectar and floral tissue are the principal resource exploited by the hoverfly. By contrast, soldier fly (Stratiomyidae) had a neutral effect on fecundity, while foraging in flowering or fruiting bracts. These findings corroborate our hypothesis, that herbivory by the larval occupants represents cost to the host plant having phytotelmata. The negative influence of this foraging on plant fecundity will nevertheless depend on the consequences of the exploitation of resources, which vary considerably in ephemeral habitats such as the phytotalmanta of flower parts.

5.
New Phytol ; 233(1): 132-144, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34363707

RESUMO

Florivory is an ancient interaction which has rarely been quantified due to a lack of standardized protocols, thus impairing biogeographical and phylogenetic comparisons. We created a global, continuously updated, open-access database comprising 180 species and 64 families to compare floral damage between tropical and temperate plants, to examine the effects of plant traits on floral damage, and to explore the eco-evolutionary dynamics of flower-florivore interactions. Flower damage is widespread across angiosperms, but was two-fold higher in tropical vs temperate species, suggesting stronger fitness impacts in the tropics. Flowers were mostly damaged by chewers, but neither flower color nor symmetry explained differences in florivory. Herbivory and florivory levels were positively correlated within species, even though the richness of the florivore community does not affect florivory levels. We show that florivory impacts plant fitness via multiple pathways and that ignoring this interaction makes it more difficult to obtain a broad understanding of the ecology and evolution of angiosperms. Finally, we propose a standardized protocol for florivory measurements, and identify key research avenues that will help fill persistent knowledge gaps. Florivory is expected to be a central research topic in an epoch characterized by widespread decreases in insect populations that comprise both pollinators and florivores.


Assuntos
Flores , Magnoliopsida , Animais , Herbivoria , Insetos , Filogenia , Polinização
6.
Naturwissenschaften ; 108(5): 39, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34477965

RESUMO

Florivores and rainfall generally have negative impacts on plant fecundity. However, in some cases, they can mediate fruit set. Some plants face severe pollen-limited fecundity and any additional fruit set, even if from self-pollination, can be advantageous. This is the case in some tropical deceptive orchids, such as the threatened Cyrtopodium hatschbachii. Here we test the hypothesis that florivory of the anther cap would facilitate rain-assisted autogamy in this species. In the field, we followed flowers in which the anther cap was removed by the orthopteran Stenopola sp. and found cases where pollinia self-deposited after rainfall and in one case this resulted in swelling of the column typical of fruit development. This event comprised 33% of all fruit set in the population in 2019. We then experimentally varied anther cap removal and rainfall in a factorial design and found increased fruit set in the group with cap removal (simulated florivory) followed by rain. The water absorption by pollinia makes them heavier, causing the stipe to bend. The droplet of water on the stigma then shrinks and pulls the pollinia back onto the stigma, causing self-pollination. Seeds from self-pollination have considerable viability and may allow population persistence, given that bee-mediated cross-pollination is uncertain and even absent in some years. Our study provides a unique example of how two unrelated factors (i.e., florivory and rain) that are detrimental alone may together promote fruit set.


Assuntos
Orchidaceae , Polinização , Animais , Abelhas , Flores , Pólen , Chuva
7.
Front Plant Sci ; 11: 627, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32508868

RESUMO

The specialised mutualism between Tococa guianensis and ants housed in its leaf domatia is a well-known example of myrmecophily. A pollination study on this species revealed that flowers in the bud stage exude a sugary solution that is collected by ants. Given the presence of this unexpected nectar secretion, we investigated how, where, and when floral buds of T. guianensis secret nectar and what function it serves. We studied a population of T. guianensis occurring in a swampy area in the Cerrado of Brazil by analyzing the chemical composition and secretion dynamics of the floral-bud nectar and the distribution and ultrastructure of secretory tissues. We also measured flower damage using ant-exclusion experiments. Floral bud nectar was secreted at the tip of the petals, which lack a typical glandular structure but possess distinctive mesophyll due to the presence of numerous calcium oxalate crystals. The nectar, the production of which ceased after flower opening, was composed mainly of sucrose and low amounts of glucose and fructose. Nectar was consumed by generalist ants and sporadically by stingless bees. Ant exclusion experiments resulted in significantly increased flower damage. The floral nectar of T. guianensis is produced during the bud stage. This bud-nectar has the extranuptial function of attracting generalist ants that reduce florivory. Pollen is the unique floral resource attracting pollinators during anthesis. Tococa guianensis, thus, establishes relationships with two functional groups of ant species: specialist ants acting against herbivory and generalist ants acting against florivory.

8.
Zootaxa ; 4369(4): 587-599, 2018 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-29689874

RESUMO

A new species of the genus Beebeomyia Curran found in the northern coastal region of the state of Pernambuco, northeastern Brazil is described and illustrated, including characteristics of the male and female terminalia, third instar larva and puparium. This new species is only the second record for the genus in Brazil and broadens its occurrence to the Atlantic Forest ecoregion. Beebeomyia taccarivora sp. nov. is straightforwardly distinguishable from all other known species of Beebeomyia for exhibiting an entirely yellowish orange thorax with a central brown-colored stripe on the scutum, and a brownish orange abdomen with a central brown stripe on tergites 1-4. Similarly to what had been previously described for congenerics, female B. taccarivora flies exclusively use the inflorescences of their host plant, Taccarum ulei, as oviposition and brooding sites. Developing larvae feed on living floral tissue and pollen, and pupariation occurs within the inner surface of the spathe.


Assuntos
Dípteros , Animais , Araceae , Brasil , Feminino , Larva , Masculino , Oviposição
9.
R. Ci. agrovet. ; 17(1): 128-135, 2018. tab
Artigo em Português | VETINDEX | ID: vti-734026

RESUMO

Poiretia latifolia Vogel (Fabaceae), is a promising plant native of the altitude field ecosystem, inserted in the Atlantic Forest biome in the southern region of Brazil. It is valued for its monoterpene-rich essential oil and exhibits great potential in the pharmaceutical and cosmetic industries. This work aimed at studying the entomofauna associated with P. latifolia, as well as assessing the effects of these insects on this plant's reproductive success. The entomofauna were surveyed between December 2015 and January 2016, in two natural P. latifolia stands found in the Capão Alto and São José do Cerrito municipalities of Santa Catarina State. The entomofauna was monitored for 42 hours in each stand, being marked five plants in each stand that were accompanied hourly, from 9:00 am to 4:00 p.m. The effects of the climatic variables on the insect were analyzed using the Pearson correlation coefficient. To determine the damage due to herbivory, ten P. latifolia plants were marked at each stand, from which the flowers and seeds were collected and the insect damage estimated. The predominant insects in both stands were identified as belonging to the orders Coleoptera, Diptera and Hymenoptera. The Dipteran insects revealed a significant positive correlation with the mean daily temperature (r = 0.84, p = 0.03442) in the Capão Alto stand. Damages caused by insects to the P. latifolia flowers and seeds was higher in São José do Cerrito, corresponding to 54% and 88% of damaged structures, respectively. Environmental changes precipitated by the intense agricultural usage in the vicinity of the P. latifolia stands may have been the reason for these differences.(AU)


Poiretia latifolia Vogel (Fabaceae) é uma promissora planta nativa do ecossistema campos de altitude, inserido no bioma Mata Atlântica na região Sul do Brasil. Seu valor se encontra na composição do seu óleo essencial que é rico em monoterpenos com potencial de uso farmacêutico e cosmético. O objetivo deste trabalho foi estudar a entomofauna associada à P. latifolia, bem como avaliar a influência dos insetos no sucesso reprodutivo da planta. O levantamento da entomofauna foi realizado no período de dezembro de 2015 a janeiro de 2016, em dois povoamentos naturais de P. latifolia localizados nos municípios de Capão Alto e São José do Cerrito, Santa Catarina. A entomofauna foi monitorada por 42 horas em cada local, sendo marcadas cinco plantas em cada área que foram acompanhadas de hora em hora, das 9:00 às 16:00. A influência das variáveis meteorológicas sobre a presença de insetos foi analisada pelo coeficiente de correlação de Pearson. Para determinar os danos por herbivoria, foram marcadas dez plantas de P. latifolia em cada área, das quais foram coletadas flores e sementes para avaliar o dano por insetos. Insetos pertencentes às ordens Coleoptera, Diptera e Hymenoptera foram predominantes em ambos os povoamentos. A presença de insetos da ordem Diptera demonstrou correlação positiva significativa com a temperatura média diária (r = 0,84; p = 0,03442) no povoamento de Capão Alto. Os danos causados por insetos às flores e sementes de P. latifolia foram superiores em São José do Cerrito, correspondendo por 54% e 88% das estruturas danificadas, respectivamente. Alterações ambientais causadas pela intensidade de uso agrícola próximo aos povoamentos de P. latifolia podem ter causado estas diferenças.(AU)


Assuntos
Animais , Fabaceae/crescimento & desenvolvimento , Sementes , Insetos , Altitude , Brasil
10.
Rev. Ciênc. Agrovet. (Online) ; 17(1): 128-135, 2018. tab
Artigo em Português | VETINDEX | ID: biblio-1488220

RESUMO

Poiretia latifolia Vogel (Fabaceae), is a promising plant native of the altitude field ecosystem, inserted in the Atlantic Forest biome in the southern region of Brazil. It is valued for its monoterpene-rich essential oil and exhibits great potential in the pharmaceutical and cosmetic industries. This work aimed at studying the entomofauna associated with P. latifolia, as well as assessing the effects of these insects on this plant's reproductive success. The entomofauna were surveyed between December 2015 and January 2016, in two natural P. latifolia stands found in the Capão Alto and São José do Cerrito municipalities of Santa Catarina State. The entomofauna was monitored for 42 hours in each stand, being marked five plants in each stand that were accompanied hourly, from 9:00 am to 4:00 p.m. The effects of the climatic variables on the insect were analyzed using the Pearson correlation coefficient. To determine the damage due to herbivory, ten P. latifolia plants were marked at each stand, from which the flowers and seeds were collected and the insect damage estimated. The predominant insects in both stands were identified as belonging to the orders Coleoptera, Diptera and Hymenoptera. The Dipteran insects revealed a significant positive correlation with the mean daily temperature (r = 0.84, p = 0.03442) in the Capão Alto stand. Damages caused by insects to the P. latifolia flowers and seeds was higher in São José do Cerrito, corresponding to 54% and 88% of damaged structures, respectively. Environmental changes precipitated by the intense agricultural usage in the vicinity of the P. latifolia stands may have been the reason for these differences.


Poiretia latifolia Vogel (Fabaceae) é uma promissora planta nativa do ecossistema campos de altitude, inserido no bioma Mata Atlântica na região Sul do Brasil. Seu valor se encontra na composição do seu óleo essencial que é rico em monoterpenos com potencial de uso farmacêutico e cosmético. O objetivo deste trabalho foi estudar a entomofauna associada à P. latifolia, bem como avaliar a influência dos insetos no sucesso reprodutivo da planta. O levantamento da entomofauna foi realizado no período de dezembro de 2015 a janeiro de 2016, em dois povoamentos naturais de P. latifolia localizados nos municípios de Capão Alto e São José do Cerrito, Santa Catarina. A entomofauna foi monitorada por 42 horas em cada local, sendo marcadas cinco plantas em cada área que foram acompanhadas de hora em hora, das 9:00 às 16:00. A influência das variáveis meteorológicas sobre a presença de insetos foi analisada pelo coeficiente de correlação de Pearson. Para determinar os danos por herbivoria, foram marcadas dez plantas de P. latifolia em cada área, das quais foram coletadas flores e sementes para avaliar o dano por insetos. Insetos pertencentes às ordens Coleoptera, Diptera e Hymenoptera foram predominantes em ambos os povoamentos. A presença de insetos da ordem Diptera demonstrou correlação positiva significativa com a temperatura média diária (r = 0,84; p = 0,03442) no povoamento de Capão Alto. Os danos causados por insetos às flores e sementes de P. latifolia foram superiores em São José do Cerrito, correspondendo por 54% e 88% das estruturas danificadas, respectivamente. Alterações ambientais causadas pela intensidade de uso agrícola próximo aos povoamentos de P. latifolia podem ter causado estas diferenças.


Assuntos
Animais , Fabaceae/crescimento & desenvolvimento , Insetos , Sementes , Altitude , Brasil
11.
Am J Phys Anthropol ; 161(4): 591-602, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27492752

RESUMO

OBJECTIVES: Our goal is to investigate flower foraging by capuchin monkeys, a behavior rarely studied in wild primates. We ask what drives seasonal variation in florivory rates: flower quality and abundance or fluctuations in fruit and invertebrate abundances. We explore how capuchins affect the reproductive success of flower food species by quantifying the potential pollination rate. MATERIALS AND METHODS: We followed capuchin groups from dawn to dusk and recorded all flower foraging bouts. Flower food nutritional composition was compared to fruit and invertebrate foods. We recorded overall flower, fruit, and invertebrate abundances and compared the rate of flower foraging to these. We estimated the likelihood of pollination from the proportion of flower patch visits to each plant species that satisfied minimum behavioral requirements. RESULTS: Flower eating was highly seasonal, and was significantly negatively related to overall fruit and invertebrate abundance but not flower abundance. Although smaller than most fruits, flowers were nutritionally comparable to fruit foods by dry mass and contained higher average concentrations of protein. Capuchins are likely pollinators for Luehea speciosa; most foraging visits to this species occurred in a manner that makes outcrossing or geitonogamous pollination likely. DISCUSSION: Flowers are an important seasonal resource for capuchins. Flowers likely act as fallback foods during periods of reduced fruit and invertebrate abundance, and may exert evolutionary pressure disproportionate to their consumption. Capuchin florivory likely affects the reproductive success of some plants, potentially shaping forest structure. Our study illustrates the value of assessing the importance of rare foods in the primate diet.


Assuntos
Cebus/fisiologia , Comportamento Alimentar/fisiologia , Flores , Animais , Antropologia Física , Evolução Biológica , Costa Rica , Comportamento de Retorno ao Território Vital/fisiologia , Estações do Ano , Clima Tropical
12.
Rev. bras. entomol ; Rev. bras. entomol;58(3): 309-312, July-Sept. 2014. ilus, tab
Artigo em Inglês | LILACS | ID: lil-724042

RESUMO

Lycaenid caterpillars (Lepidoptera, Lycaenidae) eating flowers of Dalea pennellii var. chilensis (Fabaceae) in the northern Chilean Andes. The shrub Dalea pennellii var. chilensis (Fabaceae) is reported for the first time as a host plant for three Neotropical Polyommatini (Lepidoptera, Lycaenidae, Polyommatinae): Hemiargus ramon (Dognin, 1887), Leptotes trigemmatus (Butler, 1881) and Nabokovia faga (Dognin, 1895), based on two collections performed in the western slopes of the northern Chilean Andes in two consecutive summers. The relative abundance was always above 90% for N. faga while it was always less than 5% for H. ramon and L. trigemmatus. Furthermore, N. faga was not found on inflorescences of other native Fabaceae examined in the study site. This pattern suggests a close relationship between N. faga and D. pennellii var. chilensis, at least at a local scale.

13.
Biosci. j. (Online) ; 28(1): 114-117, jan./feb. 2012. ilus
Artigo em Português | LILACS | ID: biblio-912382

RESUMO

Heliopetes arsalte (Linnaeus, 1758) (Hesperiidae, Pyrginae) é uma espécie com ampla distribuição, especialmente em vegetação aberta, e suas larvas utilizam diversas espécies de Malvaceae como plantas hospedeiras. Larvas de H. arsalte foram encontradas em inflorescências de Pavonia rosa-campestris St. Hil. (Malvaceae), sendo este um novo registro de planta hospedeira desta espécie de borboleta no cerrado do Brasil central. Ilustrações de ovo, da larva e da pupa, e a ocorrência de parasitismo da larva por Braconidae (Hymenoptera) são apresentadas.


Heliopetes arsalte (Linnaeus, 1758) (Hesperiidae, Pyrginae) is a widespread skipper butterfly, commonly found in open sites. The larvae may utilize several species of Malvaceae as host plants. In this study, larvae of H. arsalte were observed on inflorescences of Pavonia rosa-campestris St. Hil. (Malvaceae), which represents a new record of host plants for this butterfly in cerrado of central Brazil. Illustrations of the immature and adult stages, as well as the occurrence of parasitism by Braconidae (Hymenoptera) are presented.


Assuntos
Vespas , Fenômenos Biológicos , Borboletas , Magnoliopsida , Pradaria , Larva , Inflorescência
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