Flowering phenology and trap pollination of the rare endemic plant Ceropegia thaithongiae in montane forest of northern Thailand

Although Ceropegia species are well known for their complex pitfall flowers that temporarily imprison their pollinators, various aspects of their pollination ecology are still unknown. This study investigated flowering phenology, functional floral traits, and insect visitation in a natural population of a rare endemic lithophyte, Ceropegia thaithongiae Kidyoo. Flowering of C. thaithongiae was not synchronous but staggered. Anthesis lasted mostly 1–2 days, but its duration was shorter in flowers with a pollinium inserted into the stigmatic chamber. Several different insects visited flowers, but only chloropid and milichiid flies were effective pollinators. At anthesis, the epithelial osmophores on the corolla lobes emitted a floral scent that was simple in composition. Nectar of high viscosity was exuded from the nectaries hidden behind the guide rails. When transported by an insect, the pollinarium was attached to bristles on the mouthparts. Size and shape of the thin pellucid margin of the pollinium enable it to fit into the stigmatic chamber in a lock-and-key arrangement. The pollen transfer efficiency was 6.8%. The plant’s staggered flowering and pollination-induced ending of anthesis are advantageous in decreasing competition for pollinators when flower-visiting insects are scarce.

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Fly Pollination of Kettle Trap Flowers of Riocreuxia torulosa (Ceropegieae-Anisotominae): A Generalized System of Floral Deception

Plants ◽

10.3390/plants10081564 ◽

2021 ◽

Vol 10 (8) ◽

pp. 1564

Author(s):

Annemarie Heiduk ◽

Ulrich Meve ◽

Frank Menzel ◽

Jean-Paul Haenni ◽

Michael von Tschirnhaus ◽

...

Keyword(s):

Chemical Ecology ◽

Floral Scent ◽

Pollen Transfer ◽

Male And Female ◽

Intensive Research ◽

Generalized System ◽

Plant Group ◽

Pollen Transfer Efficiency ◽

Linalool Oxide ◽

Fly Pollination

Elaborated kettle trap flowers to temporarily detain pollinators evolved independently in several angiosperm lineages. Intensive research on species of Aristolochia and Ceropegia recently illuminated how these specialized trap flowers attract particular pollinators through chemical deception. Morphologically similar trap flowers evolved in Riocreuxia; however, no data about floral rewards, pollinators, and chemical ecology were available for this plant group. Here we provide data on pollination ecology and floral chemistry of R. torulosa. Specifically, we determined flower visitors and pollinators, assessed pollen transfer efficiency, and analysed floral scent chemistry. R. torulosa flowers are myiophilous and predominantly pollinated by Nematocera. Pollinating Diptera included, in order of decreasing abundance, male and female Sciaridae, Ceratopogonidae, Scatopsidae, Chloropidae, and Phoridae. Approximately 16% of pollen removed from flowers was successfully exported to conspecific stigmas. The flowers emitted mainly ubiquitous terpenoids, most abundantly linalool, furanoid (Z)-linalool oxide, and (E)-β-ocimene—compounds typical of rewarding flowers and fruits. R. torulosa can be considered to use generalized food (and possibly also brood-site) deception to lure small nematocerous Diptera into their flowers. These results suggest that R. torulosa has a less specific pollination system than previously reported for other kettle trap flowers but is nevertheless specialized at the level of Diptera suborder Nematocera.

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Pollinator effectiveness and importance between female and male mining bee ( Andrena )

Biology Letters ◽

10.1098/rsbl.2019.0479 ◽

2019 ◽

Vol 15 (10) ◽

pp. 20190479 ◽

Cited By ~ 2

Author(s):

Ju Tang ◽

Qiu-Mei Quan ◽

Jing-Zhu Chen ◽

Ting Wu ◽

Shuang-Quan Huang

Keyword(s):

Foraging Behaviour ◽

Pollen Grains ◽

Pollen Foraging ◽

Pollen Transfer ◽

Natural Ecosystems ◽

Pollinator Effectiveness ◽

Visit Frequency ◽

Pollen Transfer Efficiency ◽

Food Provision ◽

Effective Pollinators

Bees are often considered to be effective pollinators in both agricultural and natural ecosystems but could be ineffective pollinators in that they collect large quantities of pollen for food provision but deliver little to stigmas. Male bees do not collect pollen to feed larvae, and their pollination role has been underappreciated. Here we compare pollination effectiveness, visit frequency and pollen foraging behaviour between female and male individuals of a mining bee, Andrena emeishanica , visiting a nectariferous spring flower ( Epimedium pubescens ). Female bees were observed to forage for both pollen and nectar, but male bees foraged only for nectar. Female bees had large hairy hind tibiae with conspicuous scopae, and nearly 90% of the pollen grains they collected went onto the hind legs. Male bees removed less pollen from anthers than female bees but deposited more pollen on stigmas per visit. The higher pollen transfer efficiency of male bees was due to 48.4% of pollen grains remaining ungroomed on the thorax and abdomen, available for stigma contact, but their visitation rate to flowers was much lower. Our results indicate that male solitary bees could transfer more pollen on the stigma per visit but were less important (transferred less pollen in total, because they made fewer visits per unit time) than females.

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Early life history responses and phenotypic shifts in a rare endemic plant responding to climate change

Conservation Physiology ◽

10.1093/conphys/coz076 ◽

2019 ◽

Vol 7 (1) ◽

Cited By ~ 1

Author(s):

Daniel E Winkler ◽

Michelle Yu-Chan Lin ◽

José Delgadillo ◽

Kenneth J Chapin ◽

Travis E Huxman

Keyword(s):

Climate Change ◽

Life History ◽

Phenotypic Variation ◽

Early Life ◽

Early Life History ◽

Interactive Effects ◽

Endemic Plant ◽

Cushion Plant ◽

Rare Endemic

We studied how a rare, endemic alpine cushion plant responds to the interactive effects of warming and drought. Overall, we found that both drought and warming negatively influenced the species growth but that existing levels of phenotypic variation may be enough to at least temporarily buffer populations.

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Coflowering invasive plants and a congener have neutral effects on fitness components of a rare endemic plant

Ecology and Evolution ◽

10.1002/ece3.7375 ◽

2021 ◽

Author(s):

Diane L. Larson ◽

Jennifer L. Larson ◽

Amy J. Symstad ◽

Deborah A. Buhl ◽

Zachary M. Portman

Keyword(s):

Invasive Plants ◽

Endemic Plant ◽

Fitness Components ◽

Rare Endemic

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Hawkmoths evaluate scenting flowers with the tip of their proboscis

eLife ◽

10.7554/elife.15039 ◽

2016 ◽

Vol 5 ◽

Cited By ~ 24

Author(s):

Alexander Haverkamp ◽

Felipe Yon ◽

Ian W Keesey ◽

Christine Mißbach ◽

Christopher Koenig ◽

...

Keyword(s):

Wind Tunnel ◽

Manduca Sexta ◽

Ecosystem Service ◽

Floral Scent ◽

Nicotiana Attenuata ◽

Floral Volatiles ◽

Pollen Transfer ◽

Olfactory Neurons ◽

Molecular Analyses ◽

Choice Tests

Pollination by insects is essential to many ecosystems. Previously, we have shown that floral scent is important to mediate pollen transfer between plants (<xref ref-type="bibr" rid="bib16">Kessler et al., 2015</xref>). Yet, the mechanisms by which pollinators evaluate volatiles of single flowers remained unclear. Here, Nicotiana attenuata plants, in which floral volatiles have been genetically silenced and its hawkmoth pollinator, Manduca sexta, were used in semi-natural tent and wind-tunnel assays to explore the function of floral scent. We found that floral scent functions to increase the fitness of individual flowers not only by increasing detectability but also by enhancing the pollinator's foraging efforts. Combining proboscis choice tests with neurophysiological, anatomical and molecular analyses we show that this effect is governed by newly discovered olfactory neurons on the tip of the moth's proboscis. With the tip of their tongue, pollinators assess the advertisement of individual flowers, an ability essential for maintaining this important ecosystem service.

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A comparison of flower-visiting insects to rare Symphyotrichum sericeum and common Solidago nemoralis (Asteraceae)

Botany ◽

10.1139/b10-003 ◽

2010 ◽

Vol 88 (3) ◽

pp. 241-249 ◽

Cited By ~ 5

Author(s):

Diana Bizecki Robson

Keyword(s):

Seed Set ◽

Visitation Rate ◽

Hand Pollination ◽

Insect Visitation ◽

The Common ◽

Insect Activity ◽

Flower Visiting ◽

Common Plant ◽

Insect Visitors ◽

Over Time

Flower-visiting insect activity to the rare Symphyotrichum sericeum (Vent.) G.L. Nesom and the common Solidago nemoralis Ait. var. longipetiolata (Mack. & Bush) Pal. & Steyerm. was examined to detect compositional and temporal similarities. A hand pollination experiment was conducted to determine whether pollen was limiting seed set. Of the 31 insect taxa that visited these plants, Bombus bifarius Cresson was the most common visitor to both species. More insect visitors of the Halictidae and Bombyliidae were received by S. sericeum than S. nemoralis, which received more visitors of the Syrphidae and Tachinidae. The insect visitation rate was not significantly different between the two plant species. Solidago nemoralis was visited by fewer insect taxa per day than S. sericeum, but the constancy of its visitors was higher. The insect visitor composition changed over time, with B. bifarius ignoring S. sericeum plants initially, then visiting them more frequently as the number of receptive S. nemoralis capitula declined. Hand pollination increased seed set in the earliest flowering capitula of S. sericeum, but not for those flowering during the peak. This research shows that the quantity of insect visits to the rare plant is comparable with that of the common plant but that pollination quality may be lower, particularly for early blooming capitula.

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Solitary bee pollinators adjust pollen foraging to the unpredictable flower opening of a species of Petunia (Solanaceae)

Biological Journal of the Linnean Society ◽

10.1093/biolinnean/blz193 ◽

2019 ◽

Vol 129 (2) ◽

pp. 273-287

Author(s):

Fernanda Figueiredo De Araujo ◽

Reisla Oliveira ◽

Theo Mota ◽

João Renato Stehmann ◽

Clemens Schlindwein

Keyword(s):

Floral Biology ◽

Floral Resources ◽

Pollen Foraging ◽

Flower Opening ◽

Foraging Patterns ◽

Social Species ◽

Pollen Presentation ◽

Total Pollen ◽

Flower Visiting ◽

Effective Pollinators

Abstract Details of the foraging patterns of solitary bees are much less well known than those of social species, and these patterns are often adjusted to exploit floral resources of one or only a few species. The specialized flower-visiting bees of Petunia are good models for investigating such foraging patterns. Here we analysed the floral biology and pollen presentation schedule of the endangered Petunia mantiqueirensis in mixed Araucaria forests of Serra da Mantiqueira, Brazil. Pollinators and their pollen foraging behaviour and food specialization were determined through analyses of scopa pollen loads. Flowers opened throughout the day and presented all their pollen resources within the first 30 min of anthesis, thus providing their pollen resources in an asynchronous fashion in one-flower packages throughout the day. Females of Pseudagapostemon fluminensis were the most frequent flower visitors, contacting stigmas in 96% of their visits, and were the unique effective pollinators of Petunia mantiqueirensis. These pollinators were responsible for the first three visits to 115 individually monitored flowers at any daylight hour, removing ~86% of a flower’s total pollen supply during the first visit. Although female bees harvest the majority of pollen resources of Petunia mantiqueirensis, analyses of scopa loads revealed that most of them also collect pollen from plants of other families while foraging for pollen in Petunia flowers.

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Busy Bees: Variation in Insect Flower-Visiting Rates across Multiple Plant Species

Psyche A Journal of Entomology ◽

10.1155/2015/134630 ◽

2015 ◽

Vol 2015 ◽

pp. 1-7 ◽

Cited By ~ 8

Author(s):

Margaret J. Couvillon ◽

Chandra M. Walter ◽

Eluned M. Blows ◽

Tomer J. Czaczkes ◽

Karin L. Alton ◽

...

Keyword(s):

Apis Mellifera ◽

Honey Bee ◽

Plant Species ◽

Honey Bees ◽

Bumble Bees ◽

The Other ◽

Insect Diversity ◽

Visitation Rates ◽

Insect Visitation ◽

Flower Visiting

We quantified insect visitation rates by counting how many flowers/inflorescences were probed per unit time for five plant species (four native and one garden: California lilac, bramble, ragwort, wild marjoram, and ivy) growing in Sussex, United Kingdom, by following individual insects (n=2987) from nine functional groups (honey bees (Apis mellifera), bumble bees (Bombusspp.), hoverflies, flies, butterflies, beetles, wasps, non-Apidae bees, and moths). Additionally, we made a census of the insect diversity on the studied plant species. Overall we found that insect groups differed greatly in their rate of flower visits (P<2.2e-16), with bumble bees and honey bees visiting significantly more flowers per time (11.5 and 9.2 flowers/minute, resp.) than the other insect groups. Additionally, we report on a within-group difference in the non-Apidae bees, where the genusOsmia, which is often suggested as an alternative to honey bees as a managed pollinator, was very speedy (13.4 flowers/minute) compared to the other non-Apidae bees (4.3 flowers/minute). Our census showed that the plants attracted a range of insects, with the honey bee as the most abundant visitor (34%). Therefore, rate differences cannot be explained by particular specializations. Lastly, we discuss potential implications of our conclusions for pollination.

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