Orchid Pollination Research Articles

Biological Flora of Britain and Ireland:Hammarbya paludosa

AbstractThis account presents information on all aspects of the biology ofHammarbya paludosa(L.) Kuntze (bog orchid, bog adder's‐mouth orchid) (Malaxis paludosa(L.) Sw.,Ophrys paludosaL.), that are relevant to understanding its ecological characteristics and behaviour. The main topics are presented within the standard framework of theBiological Flora of Britain and Ireland: distribution, habitat, communities, responses to biotic factors, responses to environment, structure and physiology, phenology, floral and seed characters, herbivores and disease, history and conservation.Hammarbya paludosais a small bisexual perennial forb. It occurs in open habitats in bogs, mires and heaths as well as semi‐shaded open woodland and, in some areas, in shaded coniferous forest. It is found in a few locations in the southern England (the New Forest, Dorset, Devon and Cornwall), in Cumbria and Northumberland, and in western counties in Wales. It is rare in Ireland but wide spread but very local in Scotland.H. paludosahas a Holarctic circumboreal range. Ninety per cent of known locations are recorded in Northern Europe and the British Isles.Hammarbya paludosaoccurs inSphagnum, other mosses and bare peat, overlying a variety of superficial deposits and sedimentary, metamorphic and igneous rocks. The pH of the rooting substrates ranges from acidic to neutral and slightly alkaline. Its nutrient status is oligotrophic, although occasionally mesotrophic, and very rarely eutrophic. It grows well in conditions of consistent lateral flow of water in the substratum.Hammarbya paludosais visited by small insects of the order Diptera. Two species of gnats are recorded as orchid pollinators: Phronia digitataandSciara thomae. It produces a small amount of nectar but is often considered as non‐rewarding. The seeds are dust‐like, dispersed by wind and water and the species has a short‐term seed bank. Tiny bulbils (propagules) are formed on the leaf margins. They are dispersed by water.Hammarbya paludosahas declined in Britain since the late 19th century primarily due to drainage of its mire habitats in lowland regions of southern and eastern England and Wales. The decline slowed down by the 2000s, and new locations have been found in Scotland and Ireland.

Preventing inbreeding depression in Anacamptis coriophora (Orchidaceae) as a model of food-rewarding orchid

Pollination of deceptive orchids has enabled scientists to understand how these species avoid inbreeding depression by reducing the number of pollinator visits per inflorescence. In rewarding species, which receive a higher rate of visits per plant, geitonogamy is usually higher and therefore the risk of inbreeding increases. In this study, we assess the breeding system of the rewarding orchid A. coriophora, and the spatio-temporal changes in its fitness as well as variation in nectar content after pollination. We found that the species partially selects allogamous pollen if pollinia from the same stalk and other plants arrive to the stigma. Furthermore, when self-pollination occurs, despite successful fructification, seed viability is significantly lower than that of cross-pollinated plants. A. coriophora exhibits spatio-temporal variation in fitness that does not correlate with any plant feature. Moreover, nectar volume is reduced after pollination, but the sugar concentration is maintained. This study emphasizes how essential the pre-zygotic and post-zygotic reproductive barriers are for rewarding orchids to avoid inbreeding depression.

Identification of indole-3-acetic acid as an important hormone in post– pollination of Dendrobium orchids and interaction of other hormones

Identification of indole-3-acetic acid as an important hormone in post– pollination of Dendrobium orchids and interaction of other hormones

Pollination in the Rainforest: Scarce Visitors and Low Effective Pollinators Limit the Fruiting Success of Tropical Orchids.

Simple SummaryThe ability to distinguish between mere flower visitors and effective pollinators is of crucial importance to understand pollination ecology. Inefficient and scarce pollinators, coupled with unsuitable abiotic conditions, might explain a failure in plant reproductive success. Here, we quantified the levels of fruit set and tested the dependency on pollinators in 10 orchid species occurring in the tropical rainforest. We show that all species were pollinator-dependent with pollination limitation occurring in all the 20 studied populations. In fact, in 87% of our observation period no visitor was seen on the flowers studied. Floral visitors included flies, butterflies, bees, and hummingbirds although only a small number were performing effective pollinations. We conclude that although these orchid species were visited by different groups of visitors, few could be considered as legitimate pollinators, explaining why these tropical orchids present low values of fruit set.A single plant might be visited by many flower visitors but not all might act as pollinators. Legitimate pollinators might also differ considerably in their efficiency, limiting pollination success. Unsuitable climatic conditions such as rain also affect pollinator activity. However, in the evergreen rainforest there is no prolonged dry season and flowering occurs usually under rain. Here, we explore the dependence on pollinators and the efficiency of flower visitors for the fruiting success of 10 Andean rainforest orchids. All species were self-compatible but strictly pollinator-dependent. Overall, we found low levels of fruit set in control flowers while experimental geitonogamous and cross-pollinations increased fruit set, revealing extensive pollination limitation in all populations. Seed viability dropped considerably after self and geitonogamous pollinations suggesting the possibility of early-acting inbreeding depression. Even though we monitored flower visitors on an extensive survey, few visitors were seen in these species and even fewer acted as legitimate pollinators. Thus, even though orchid pollination might be extremely diversified, these results show that few visitors are pollinating these species, explaining the low levels of fruit set recorded in the area studied.

Pollination success in three tropical dry forest orchid species from Mexico: insights from floral display, visitation rates, and flower micromorphology

Background: Despite long-lasting efforts to disentangle the drivers of orchid pollination, pollination success in tropical dry forest orchids remains largely unknown.
 Questions and hypothesis: How successful are pollination in three tropical dry forest orchids? How is pollination influenced by floral display and floral rewards (as suggested by floral micromorphology)? We hypothesized a positive effect of floral display on pollinia removal and deposition rates.
 Studied species: Barkeria whartoniana (C. Schweinf.) Soto Arenas, Clowesia dodsoniana E. Aguirre, and Cyrtopodium macrobulbon (La Llave & Lex.) G.A. Romero & Carnevali.
 Study site and dates: Nizanda (Oaxaca), Mexico; flowering periods of 2013 and 2014.
 Methods: We calculated pollinia removal and deposition rates, identified floral visitors and analyzed flower microstructure to search for structures potentially producing rewards. Floral display was measured through number of open flowers, and number and length of inflorescences, and its effect on pollination success was assessed through linear modeling.
 Results: Pollinia removal rates were higher than deposition rates, and floral display was related to pollination success in C. dodsoniana only. Visitation rates were low for the three species and most visitors were not true pollinators. The three species possess potentially secreting structures, but for B. whartoniana and C. macrobulbon these rewards are likely part of the pollinator deception mechanism.
 Conclusions: The generalized low pollination success implies the need for high population densities of both interacting parts. We emphasize the need for integrated evaluations of different aspects of the plant-pollinator interaction.

An unusual tricosatriene is crucial for male fungus gnat attraction and exploitation by sexually deceptive Pterostylis orchids

Cross-kingdom mimicry of female insect sex pheromones by sexually deceptive orchids has evolved multiple times.1 Fungus gnats (Diptera) are predicted to be pollinators of hundreds of sexually deceptive orchids,2-4 yet unlike orchids that sexually attract bees and wasps (Hymenoptera),5-11 the chemistry of fungus gnat-pollinated orchids remains unknown. Furthermore, despite the importance of fungus gnats as pollinators, pests, and decomposers of organic material, and evidence for sex pheromones since 1971,12-17 no structure of any fungus gnat sex pheromone has to date been confirmed. In this study, we found a mixture of five hydrocarbons shared between Pterostylis orbiculata orchids and female Mycomya sp. (Mycetophilidae) fungus gnats, which included three alkanes, a C23 diene, and a C23 triene. The triene was an undescribed natural product, which we synthesized and confirmed to be (6Z,9Z)-1,6,9-tricosatriene. Field bioassays with a synthetic blend of the five hydrocarbons elicited attraction and sexual behavior from male gnats. The triene alone elicited attraction and low levels of sexual behavior, but the blend without it was unattractive, suggesting that this compound is a key component of orchid pollinator attraction and the female fungus gnat sex pheromone. In two closely related Pterostylis species, we found related C23 trienes, but not (6Z,9Z)-1,6,9-tricosatriene. These results suggest that unusual long-chain unsaturated hydrocarbons hold the key to sexual deception in Pterostylis orchids, and are an important step toward deciphering female fungus gnat sex pheromones.

“Push and Pull”: Biomechanics of the Pollination Apparatus of Oncidium spp.

Comprising ca. 28,000, species the Orchidaceae constitute one of the most species-rich plant families. Orchids differ from other monocotyledons i.a., in the formation of so-called pollinaria, which are entities consisting of pollen grains aggregated into compact pollinia and accessory structures, a viscidium and mostly also a pollinium stalk. The viscidium releases an adhesive material that attaches the pollinarium to a pollinator. Pollinaria are part of a complex pollination apparatus that enables the orchids to colonize niches in which only a few individuals of the respective pollinator occur infrequently. Because the aggregated pollen grains are removed from the flower at once, the development of a mechanical barrier ensuring that only suitable pollinators are able to access the flowers and more importantly to remove the pollen are important selective traits. In this paper we describe the functional morphology of the pollination apparatus in two orchid species,Oncidium wentworthianumandO. otogaya, by experimentally mimicking the pollination process. Furthermore, we analyzed the mechanical resistance of this apparatus by means of force measurements and showed that it most probably constitutes a hierarchical two-stage barrier. The first stage consists of the presence of the anther cap that not only protects the pollinia, but also serves to prevent premature removal of young and unripe pollinaria from the flower. As soon as the pollinaria are ripe, the anther cap sheds and the second stage of the mechanical barrier takes effect, a severable bond between pollinarium and rostellum. This bond can be overcome by a potential pollinator, applying a load of at least 10.8 mN (O. otogaya) or 12.6 mN (O. wentworthianum), respectively, on the viscidium which at the same time disengages the pollinarium from its anchorage. The adhesive material produced by the viscidium creates sufficient adhesive contact between pollinarium and pollinator. Potential pollinators, such asCentrisspp. orTrigonaspp. bees, should be well able to exert such forces by pushing their head/forebody into the orchid flowers. Thus, whether a pollinator is able to detach the pollinarium depends on both how forcefully it can push and how strongly it can pull the orchid pollination apparatus.

Orchid Bsister gene PeMADS28 displays conserved function in ovule integument development

The ovules and egg cells are well developed to be fertilized at anthesis in many flowering plants. However, ovule development is triggered by pollination in most orchids. In this study, we characterized the function of a Bsister gene, named PeMADS28, isolated from Phalaenopsis equestris, the genome-sequenced orchid. Spatial and temporal expression analysis showed PeMADS28 predominantly expressed in ovules between 32 and 48 days after pollination, which synchronizes with integument development. Subcellular localization and protein–protein interaction analyses revealed that PeMADS28 could form a homodimer as well as heterodimers with D-class and E-class MADS-box proteins. In addition, ectopic expression of PeMADS28 in Arabidopsis thaliana induced small curled rosette leaves, short silique length and few seeds, similar to that with overexpression of other species’ Bsister genes in Arabidopsis. Furthermore, complementation test revealed that PeMADS28 could rescue the phenotype of the ABS/TT16 mutant. Together, these results indicate the conserved function of BsisterPeMADS28 associated with ovule integument development in orchid.

Coleoptera and Hymenoptera Associated with Orchids at el Cielo, Mexico

The coleopteran Stethobaroides nudiventris was found in flowers of the epiphytic orchid Catasetum integerrimum and the ant Paratrechina longicornis in the Trichocentrum cebolleta epiphytic orchid in the field. This is the first report of S. nudiventris at Tamaulipas, expanding its distribution in northeastern Mexico, and is the second record as a visitor to the orchid. This is the first report of P. longicornis in flowers of T. cebolleta. Knowledge of potential orchid pollinators and pests is of utmost importance as a reference for future studies, because the knowledge is scarce in the northern Neotropical zone.

The Recognition and Valence Evaluation of Key Floral Odor in Reward and Deceptive Pollinations

Pollination originates from inadvertent interaction between plants and insects, and consequently shapes their traits. These attractions of insects are beneficial to both parties in reward pollinations, while in deceptive pollinations, they are supposed to be neutral/antagonistic to insects. However, deceptive pollinations with seemingly evolutionary disadvantage widely exist, especially in Orchidaceae. Here we explore this paradox through dissecting the neural basis preserving the floral attraction of pollinators. We first decoded the perception of the attractive floral odor ethyl tiglate (ET) emitted from orchid C. bardolphianum to implement a Drosophila deceptive pollination. Using the neurogenetic model, D. melanogaster, we unveiled the neural basis underlying the recognition and valence evaluation of ET. Furthermore, we demonstrate that the universal ET-attraction occurs in the pollination of both reward and rewardless orchids and roots in the similar neural basis of various Drosophila pollinators. Consequently, our result suggest that the diverse pollinating interactions share related attractive signals based on the corresponding neural basis of different insects.

Ecological factors driving pollination success in an orchid that mimics a range of Fabaceae

AbstractRewarding plants can enhance the pollination success of co-occurring plants pollinated by food mimicry. However, it is not always possible to readily discern between the effect of model and magnet species. Here, we tested for mimicry of co-occurring Fabaceae by the rewardless Diuris magnifica (Orchidaceae) and whether the number of flowers of Fabaceae, habitat remnant size and frequency of conspecifics, influenced the pollination success of D. magnifica. Trichocolletes bees were the primary pollinators of D. magnifica, on which they displayed similar behaviour as seen when feeding on Fabaceae. Quantification of spectral reflectance suggested that flowers of Bossiaea eriocarpa, Daviesia divaricata and Jacksonia sternbergiana may represent models for D. magnifica, whereas Hardenbergia comptoniana strongly differed in colour. Orchid pollination success was not directly affected by the number of model flowers, but the pollination rate was enhanced by increased numbers of Hardenbergia flowers. Pollination success of the orchid decreased with higher density of conspecifics, but did not exhibit a significant relationship with Trichocolletes occurrence, possibly because of the contribution of sub-optimal pollinator species. Fruit set of the orchid was greater in larger habitat remnants. Overall, pollination success of D. magnifica is affected by ecological factors related to the effectiveness of mimicry, numbers of co-flowering plants and anthropogenic landscape alteration.

Orchid-pollinator network in Euro-Mediterranean region: What we know, what we think we know, and what remains to be done

Facing the threat of global change, there is an urgent need to document our current knowledge about the interactions between plants and their pollinators, especially for species with specialized pollination strategies. We review orchid-pollinator networks in the Euro-Mediterranean region by providing an overview and a critical analysis of our current knowledge on pollination interaction. This review is organized in three parts: what we know, what we think we know and what remains to be done. Firstly, by relying on the recent orchid-pollinator network analyses, we investigate in detail what we know in terms of pollinator preferences as well as in terms of orchid pollination strategies. Even if at least one pollinator species is recorded for about half of the species of orchids in the Euro-Mediterranean region, we show that our knowledge of the orchid pollinator interaction stays largely imperfect. Secondly, we have identified several biases in what we think we know about orchid-pollinator interactions, by i) examining potential mistakes about species identification, but also potential biases induced by preconceived beliefs about the highly specialized pollination of Ophrys and also about the expected abundance of pollinators on nectar-producing orchids and ii) revealing a novel and promising research avenue concerning the sex of the pollinator and the strategy used by orchids to attract their pollinators. Thirdly, we have identified what remains to be done to give priority to the Euro-Mediterranean countries and orchid taxa which are still neglected or insufficiently studied. Finally, we propose several dos and don'ts to improve our knowledge of orchid-pollinator network by using a structured approach that is common to all field naturalists and scientists working on this fascinating topic.

The olfactory basis of orchid pollination by mosquitoes.

Mosquitoes are important vectors of disease and require sources of carbohydrates for reproduction and survival. Unlike host-related behaviors of mosquitoes, comparatively less is understood about the mechanisms involved in nectar-feeding decisions, or how this sensory information is processed in the mosquito brain. Here we show that Aedes spp. mosquitoes, including Aedes aegypti, are effective pollinators of the Platanthera obtusata orchid, and demonstrate this mutualism is mediated by the orchid's scent and the balance of excitation and inhibition in the mosquito's antennal lobe (AL). The P. obtusata orchid emits an attractive, nonanal-rich scent, whereas related Platanthera species-not visited by mosquitoes-emit scents dominated by lilac aldehyde. Calcium imaging experiments in the mosquito AL revealed that nonanal and lilac aldehyde each respectively activate the LC2 and AM2 glomerulus, and remarkably, the AM2 glomerulus is also sensitive to N,N-diethyl-meta-toluamide (DEET), a mosquito repellent. Lateral inhibition between these 2 glomeruli reflects the level of attraction to the orchid scents. Whereas the enriched nonanal scent of P. obtusata activates the LC2 and suppresses AM2, the high level of lilac aldehyde in the other orchid scents inverts this pattern of glomerular activity, and behavioral attraction is lost. These results demonstrate the ecological importance of mosquitoes beyond operating as disease vectors and open the door toward understanding the neural basis of mosquito nectar-seeking behaviors.

Interaction of milkweed butterflies with egret and jewel orchids: observations on pollinaria attachment to danaid butterflies on east Sulawesi (Indonesia) (Lepidoptera: Nymphalidae: Danainae; Orchidoideae: Habenarinae and Goodyerinae)

Species of the butterfly subfamily Danainae visit orchids, resulting in pollinaria being attached to their heads. In several habitats in east Sulawesi a remarkable percentage of Danainae specimens was observed with orchid pollinaria preferentially attached to their eyes. Among the 13 observed native Danainae species, seven carried pollinaria. Pollinaria attachment appears to be selective for Danainae as hundreds of specimens from other butterfly families were negative. Selectivity also concerns the orchid species, as attached pollinaria could be assigned to a Habenaria orchid and in one case only to an Anoectochilus. Efficient pollinaria attachment requires compatible morphological characters of butterfly and orchid. In this respect, the observed high pollinaria load of single butterflies is also important. Comparable investigations in southeast Sulawesi did not reveal danaid–orchid interactions. Further studies are required to prove orchid pollination by Danainae and to clarify the mechanism by which these butterflies are attracted to the orchids.

Pollination ecology of the ghost orchid (Dendrophylax lindenii): A first description with new hypotheses for Darwin\u2019s orchids

The structural variation of orchids enables myriad fascinating symbiotic relationships with organisms across kingdoms. Orchids are frequently known for having elaborate arms races with their pollinators that result in intricate morphologies in both parties, and flowers with long corollas hypothesized to be pollinated only by individual species of long tongued hawkmoths are of particular concern for conservation. Florida’s endangered ghost orchid, Dendrophylax lindenii, has long been confidently assumed to be pollinated by one species (Cocytius antaeus), despite the presence of a resident community of multiple suitable long-tongued candidates. Here we present the first description of ghost orchid pollination, and describe novel remote camera trapping methods. Pollination of D. lindenii by Pachylia ficus disproves long-standing hypotheses concerning the pollination ecology of long-spurred orchids, and new multiple pollinator hypotheses are proposed. We discuss the broader implications for the conservation of an endangered species, orchids globally, and the importance of Everglades restoration.

Butterfly pollination of Bonatea cassidea (Orchidaceae): Solving a puzzle from the Darwin era

Although moths and butterflies are closely related, they tend to respond to different floral cues for foraging and thus select for different suites of floral traits. Shifts between moth and butterfly pollination in the same plant clade provide an opportunity to assess the traits that are required to impart a shift between these pollination systems. The orchid genus Bonatea consists mostly of night-scented moth-pollinated taxa, but here we document a butterfly pollination system in Bonatea cassidea, a century after Mansel Weale's initial observations of butterflies carrying pollinaria of this taxon in South Africa were communicated to the Linnean Society by Charles Darwin. We recorded visits by a number of species of butterflies from the family Hesperiidae and Pieridae, but contrary to Weale, we found that the majority of pollinaria were firmly affixed between the palpi and not on the sternum. Removal of pollinaria from flowers during the day, but not at night, suggested that moths do not contribute to pollination, despite the white flower colouration. Floral traits found in B. cassidea but not its moth-pollinated congeners include diurnal anthesis, scent emission which is weak in the day and virtually absent at night, and the production of small amounts of relatively dilute sucrose-rich nectar in short spurs. These features are consistent with those expected for butterfly-pollinated plants in general. This study represents the first detailed report of butterfly-pollination in Bonatea and one of very few cases of orchid pollination by pierid butterflies.

Charles Darwin on Catasetinae (Cymbidieae, Orchidaceae)

The background and accomplishments of Darwin's work on Catasetinae are analyzed, and issues that he and others did not resolve are discussed in detail. The segments on Catasetinae published by Darwin in the Annals and Magazine of Natural History in September 1869 and in the second edition of his orchid pollination opus (as Catasetidae) published in 1877, as well as his paper “On the three remarkable sexual forms of Cataseum tridentatum,” all including the text, plates, and notes, are presented in three appendixes.

Effect of pollination strategy, phylogeny and distribution on pollination niches of Euro‐Mediterranean orchids

Abstract Pollination niches are important components of ecological niches and have played a major role in the diversification of Angiosperms. In this study, we focused on Euro‐Mediterranean orchids, which use diverse pollination strategies and interact with various functional groups of insects. In these orchids, we investigated the determinants of pollination niche breadth and overlap by analysing the orchid–pollinator network and the factors that may have shaped it. We constructed a database reporting 1,278 interactions between 243 orchid and 773 pollinator species based on a thorough literature review. We then focused on 153 orchid species for which phylogenetic data were available. We used Bayesian phylogenetic mixed models to study the relationship between specialisation (as estimated by the degree and degree in the projected network), pollination strategy and breadths of orchids’ spatial and temporal distributions, while correcting for the effect of phylogenetic relationships among orchid species and sampling effort. We then used a singular value decomposition of the orchid–pollinator matrix combined to a redundancy and variation partitioning analyses to investigate the determinants of similarity in pollination niches between orchids. Specialisation was higher in deceptive than in nectar‐producing orchids and decreased with the breadth of orchids’ spatial distribution. When interactions were considered at the insect family level, similarity in pollination niches between orchids was solely explained by their pollination strategy and phylogeny. By contrast, when they were considered at the insect species level, this similarity was primarily explained by their geographical range and flowering time, although other factors had significant effects as well, with orchids using the same pollination strategy, being closely related and growing in the same habitats sharing more insect species than expected. Synthesis. Specialisation in orchid–pollinator interactions depends on orchids’ pollination strategy and geographical range. The pool of insect families with which orchids interact depends on their pollination strategy and phylogeny, with consistent associations between some functional or phylogenetic groups of orchids and some families of pollinators. By contrast, the pool of insect species with which orchids interact depends on their spatio‐temporal distribution, suggesting that at a finer scale, orchid–pollinator interactions are more opportunistic than previously thought.

The Biosynthesis of Unusual Floral Volatiles and Blends Involved in Orchid Pollination by Deception: Current Progress and Future Prospects.

Flowers have evolved diverse strategies to attract animal pollinators, with visual and olfactory floral cues often crucial for pollinator attraction. While most plants provide reward (e.g., nectar, pollen) in return for the service of pollination, 1000s of plant species, particularly in the orchid family, offer no apparent reward. Instead, they exploit their often specific pollinators (one or few) by mimicking signals of female insects, food source, and oviposition sites, among others. A full understanding of how these deceptive pollination strategies evolve and persist remains an open question. Nonetheless, there is growing evidence that unique blends that often contain unusual compounds in floral volatile constituents are often employed to secure pollination by deception. Thus, the ability of plants to rapidly evolve new pathways for synthesizing floral volatiles may hold the key to the widespread evolution of deceptive pollination. Yet, until now the biosynthesis of these volatile compounds has been largely neglected. While elucidating the biosynthesis in non-model systems is challenging, nonetheless, these cases may also offer untapped potential for biosynthetic breakthroughs given that some of the compounds can be exclusive or dominant components of the floral scent and production is often tissue-specific. In this perspective article, we first highlight the chemical diversity underpinning some of the more widespread deceptive orchid pollination strategies. Next, we explore the potential metabolic pathways and biosynthetic steps that might be involved. Finally, we offer recommendations to accelerate the discovery of the biochemical pathways in these challenging but intriguing systems.

Are food‐deceptive orchid species really functionally specialized for pollinators?

AbstractFood‐deceptive orchid species have traditionally been considered pollination specialized to bees or butterflies. However, it is unclear to which concept of specialization this assumption is related; if to that of phenotypic specialization or of functional specialization. The main aim of this work was to verify if pollinators of five widespread food‐deceptive orchid species (Anacamptis morio (L.) R.M. Bateman, Pridgeon & M.W. Chase, Anacamptis pyramidalis (L.) Rich., Himantoglossum adriaticum H. Baumann, Orchis purpurea Huds. and Orchis simia Lam.) predicted from the phenotypic point of view matched with the observed ones. We addressed the question by defining target orchids phenotypic specialization on the basis of their floral traits, and we compared the expected guilds of pollinators with the observed ones. Target orchid pollinators were collected by conducting a meta‐analysis of the available literature and adding unpublished field observations, carried out in temperate dry grasslands in NE Italy. Pollinator species were subsequently grouped into guilds and differences in the guild spectra among orchid species grouped according to their phenotype were tested. In contradiction to expectations derived from the phenotypic point of view, food‐deceptive orchid species were found to be highly functionally generalized for pollinators, and no differences in the pollinator guild spectra could be revealed among orchid groups. Our results may lead to reconsider food‐deceptive orchid pollination ecology by revaluating the traditional equation orchid‐pollination specialization.