First confirmed case of pseudocopulation in terrestrial orchids of South America: Pollination of Geoblasta pennicillata (Orchidaceae) by Campsomeris bistrimacula (Hymenoptera, Scoliidae)

The attraction of male pollinating insects by sexual deception is known for several orchids from the Mediterranean, Australia, South Africa and South America. The sexual delusion may be so enticing in some species that it elicits males to attempt copulation with insect-like structures of the labellum. Pollination by such a pseudocopulation mechanism is reported here for the terrestrial orchid Geoblasta penicillata (Chloraeinae) from subtropical South America. Observations of the pollination process were carried out in two wild populations 560 km distant from each other. The only pollinators seen in both populations were male Campsomeris bistrimacula (Scoliidae) wasps. They attempted copulation with the insect-like labellum by directing the genitalia to its base whereby pollinia got attached to the dorsal surface of the metasoma. The present case of pseudocopulation, which is in South America the second known and the first recorded in wild populations, represents a striking parallel to the Australian Calochilus campestris also pollinated by male scoliid wasp of the genus Campsomeris.     

Bird pollination in South African species ofSatyrium (Orchidaceae)

Field observations showed that three South African orchid species,Satyrium carneum, S. coriifolium andS. princeps, are pollinated by sunbirds. Foraging sunbirds insert their bills into the labellum chamber of the flowers and suck nectar from the labellum spurs with their tongues. The column overarches the entrance to the labellum and pollinaria become affixed to the upper mandible of the bill. Birds often attempt to remove pollinaria by rubbing their bills against a branch, but are mostly unsuccessful due to the large plate-like viscidia which attach the pollinaria very firmly to the bill. Other modifications for bird pollination in theseSatyrium species may include the red, carmine or orange colour of the flowers, sturdy inflorescence stems used for perching and large amounts of dilute nectar in the spurs. EachSatyrium species was pollinated by several species of sunbird, and despite some differences in flowering time, occasional hybrids occur at a site whereS. carneum andS. coriifolium share the same sunbird pollinators.     

蝴蝶兰花发育的分子生物学研究进展

蝴蝶兰花非常独特且高度进化,如萼片瓣化、瓣片特化为唇瓣、雌雄蕊合生成合蕊柱及子房发育须由授粉启动等,是单子叶植物花发育研究的理想材料。近年来蝴蝶兰花发育分子生物学取得了重要进展。该文就近年来国内外有关蝴蝶兰开花转换及花器官发育相关基因研究以及B类基因与兰花花被的进化发育关系方面的研究进展进行综述。研究表明:MADS基因在蝴蝶兰开花转换及花器官发育过程中起重要作用,推测其中的DEF(DE-FICIENS)-like基因早期经过2轮复制,形成了4类不同的DEF-like基因,进而决定兰花花被属性。蝴蝶兰花发育分子生物学的深入研究,将极大地利于通过基因工程手段提高蝴蝶兰花品质如花色改良及花期调控等,推动分子育种进程。     

The pollination ecology ofBletilla striata (Orchidaceae)

Anthecological observations of an orchidBletilla striata were carried out in Kobe, Japan. The purplish pink flowers were visited by 26 species of insects belonging to Hymenoptera, Diptera and Lepidoptera, although the flower did not offer food rewards of any kind. Candidates for pollination were seven species of aculeate Hymenoptera with a body size that well fitted the space in between the column and labellum. The most effective candidate was the male of the longhorn beeTetralonia nipponensis, judging from its abundance and legitimate intrafloral behavior. The female ofT. nipponensis and the other six species also contributed to promote out-crossing, but to a lesser extent than the maleT. nipponensis, since they occasionally exhibited illegitimate intrafloral behaviors for pollination and also, their flower visitation rate was lower.     

Evolution,pollination, and systematics of the tribeNeottieae (Orchidaceae)

The various classifications of the orchid tribeNeottieae are reviewed and a new classification is proposed that divides the tribe into three subtribes,Neottiinae, Limodorinae, andCephalantherinae, based primarily on characters of the column (gynostemium). A cladistic analysis illustrates that these three subtribes are more closely related to one another than either is to any other group in subfam.Neottioideae, although there are very few apomorphic characters for the tribe. Pollination biology is also discussed showing links between breeding systems and distribution. There is also a possible role between column and labellum morphology and the emergence of a deceptive pollination syndrome from one of reward.     

Caught in the act: pollination of sexually deceptive trap-flowers by fungus gnats in Pterostylis (Orchidaceae)

Background and Aims Pterostylis

is an Australasian terrestrial orchid genus of more than 400 species, most of which use a motile, touch-sensitive labellum to trap dipteran pollinators. Despite studies dating back to 1872, the mechanism of pollinator attraction has remained elusive. This study tested whether the fungus gnat-pollinated Pterostylis sanguinea secures pollination by sexual deception.

Methods

The literature was used to establish criteria for confirming sexual deception as a pollination strategy. Observations and video recordings allowed quantification of each step of the pollination process. Each floral visitor was sexed and DNA barcoding was used to evaluate the degree of pollinator specificity. Following observations that attraction to the flowers is by chemical cues, experimental dissection of flowers was used to determine the source of the sexual attractant and the effect of labellum orientation on sexual attraction. Fruit set was quantified for 19 populations to test for a relationship with plant density and population size.

Key Results

A single species of male gnat (Mycetophilidae) visited and pollinated the rewardless flowers. The gnats often showed probing copulatory behaviour on the labellum, leading to its triggering and the temporary entrapment of the gnat in the flower. Pollen deposition and removal occurred as the gnat escaped from the flower via the reproductive structures. The labellum was the sole source of the chemical attractant. Gnats always alighted on the labellum facing upwards, but when it was rotated 180 ° they attempted copulation less frequently. Pollination rate showed no relationship with orchid population size or plant density.

Conclusions

This study confirms for the first time that highly specific pollination by fungus gnats is achieved by sexual deception in Pterostylis. It is predicted that sexual deception will be widespread in the genus, although the diversity of floral forms suggests that other mechanisms may also operate.     

腐生植物无叶美冠兰食源性欺骗传粉研究

无叶美冠兰是一种典型的腐生兰科植物,为揭示该物种的自然传粉机制,拓展对兰科植物生殖特性的认识,在广西雅长兰科植物国家级自然保护区对其开展了传粉生态学观测研究。结果表明:无叶美冠兰花朵具备高度自交亲和能力,但不存在自动自花授粉机制,必须依赖外部传粉媒介把花粉送到柱头,实现有效传粉;绿彩带蜂是无叶美冠兰唯一有效传粉昆虫;传粉昆虫与花朵在与传粉功能相关的关键性状在形态上良好拟合;绿彩带蜂的访花活动主要发生在3个阶段:8.6%发生在9:00~11:30,80.2%发生在11:30~14:00,11.2%发生在14:00~15:30;花朵在中午强烈的阳光直射下挥发出香甜的气味。无叶美冠兰花朵主要通过挥发极具诱惑力的香甜气味和唇瓣上黄色的蜜导来诱导绿彩带蜂进入花朵中觅食,传粉昆虫与花朵在与传粉功能相关的关键性状在形态上良好拟合促成有效传粉,绿彩带蜂在整个传粉过程没有获得报酬,是食源性欺骗传粉机制。     

Pseudocopulatory pollination in lepanthes (orchidaceae: pleurothallidinae) by fungus gnats

BACKGROUND AND AIMS: Lepanthes is one of the largest angiosperm genera (>800 species). Their non-rewarding, tiny and colourful flowers are structurally complex. Their pollination mechanism has hitherto remained unknown, but has been subject of ample speculation; the function of the minuscule labellum appendix is especially puzzling. Here, the pollination of L. glicensteinii by sexually deceived male fungus gnats is described and illustrated. METHODS: Visitors to flowers of L. glicensteinii were photographed and their behaviour documented; some were captured for identification. Occasional visits to flowers of L. helleri, L. stenorhyncha and L. turialvae were also observed. Structural features of flowers and pollinators were studied with SEM. KEY RESULTS: Sexually aroused males of the fungus gnat Bradysia floribunda (Diptera: Sciaridae) were the only visitors and pollinators of L. glicensteinii. The initial long-distance attractant seems to be olfactory. Upon finding a flower, the fly curls his abdomen under the labellum and grabs the appendix with his genitalic claspers, then dismounts the flower and turns around to face away from it. The pollinarium attaches to his abdomen during this pivoting manoeuvre. Pollinia are deposited on the stigma during a subsequent flower visit. The flies appear to ejaculate during pseudocopulation. The visitors of L. helleri, L. stenorhyncha and L. turialvae are different species of fungus gnats that display a similar behaviour. CONCLUSIONS: Lepanthes glicensteinii has genitalic pseudocopulatory pollination, the first case reported outside of the Australian orchid genus Cryptostylis. Since most species of Lepanthes have the same unusual flower structure, it is predicted that pollination by sexual deception is prevalent in the genus. Several morphological and phenological traits in Lepanthes seem well suited for exploiting male fungus gnats as pollinators. Correspondingly, some demographic trends common in Lepanthes are consistent with patterns of male sciarid behaviour.     

Floral mimesis inThelymitra nuda (Orchidaceae)

Insect pollination occurred inThelymitra nuda R. Br. on sunny days when the ambient temperature exceeded 20 °C. The flower buds on a raceme opened subsynchronously displaying the brightly-colored, actinomorphic perianth and exposed the contrastingly-colored, scented and ornamented column. InT. nuda the staminodes and the filament of the fertile stamen are fused to one another producing an inflated hood over the anther. This staminodal hood is terminated in two non-ornamental, but brightly-colored, central lobes and two terete lateral lobes bearing approximately 400 white trichomes. Each trichome bears a double chain of 30–40 spherical, rugulose cells. Female bees, in the genusLasioglossum (Halictidae), were observed to land directly on the hood and curled their bodies around the four lobed tip of the staminodal complex. The bees attempted to forage on the lobes as if they were collecting pollen from fertile, poricidal stamens. These bees applied thoracic vibration to the yellowish central lobes and actively scraped the trichome clusters (Pseudopollen) with their forelegs. Bees carried the pollinaria ofT. nuda dorsally on their abdomens. Abdominal contact with the rostellum appeared to occur when the female bee disengaged herself from the staminodal hood. Observations made of bees on co-blooming flowers, and analyses of pollen loads collected by bees suggested that the orchid flower mimics the guild of blue-purple flowers that lack floral nectar but offer pollen in poricidal anthers. The models ofT. nuda are co-bloomingLiliaceae in the generaDichopogon andThysanotus. However, nectarless, buzz-pollinated flowers are also extensively distributed over the orchid’s range. More than 30% of the flowers in theT. nuda population had their pollinaria removed, suggesting a high capacity for cross-pollination in an orchid genus usually considered to be self-pollinated via mechanical autogamy. This study confirmed previous predictions that column modifications represented a trend towards pseudanthery.     

植物园迁地保护环境下纹瓣兰的繁殖生物学研究

深入了解濒危物种的繁殖特性,能为物种制定有效保护策略提供科学依据。于2022和2023年对中国科学院西双版纳热带植物园迁地保存的纹瓣兰(Cymbidium aloifolium)的繁殖生物学特征进行了观察和研究,主要包括开花物候、繁育系统、花部形态特征、昆虫传粉特征以及花的挥发性成分等。结果表明,纹瓣兰的盛花期在4月中旬,单花花期7 d;群体花期约为36 d。花粉活力在开花第1天时最高,约为47.15%,之后呈下降趋势。柱头在整个单花期一直具可授性,开花第2天可授性最强。人工授粉实验表明纹瓣兰自交亲和,不存在无融合生殖和自动自花授粉,繁育系统属于兼性异交繁育并依赖传粉者,自然结实率较低为6.9%。唇瓣的先端和基部的表皮细胞分别为锥形和指状突起,基部的指状突起细胞外附着有油脂颗粒,可能是传粉者的报酬。药帽黄色,其表皮细胞为锥形细胞,能够反射光线,可能起到吸引昆虫的作用,中华蜜蜂(Apis cerana)是纹瓣兰唯一的有效传粉昆虫。纹瓣兰的挥发性气味中(E)-乙酸-2-癸烯-1-醇酯含量最高。因此,纹瓣兰的花部结构与传粉昆虫具有显著的适应性。     

Pollination ofNuphar (Nymphaeaceae) in Europe: Flies and bees rather thanDonacia beetles

Nuphar (Nymphaeaceae) comprises a small holarctic group of aquatic perennials whose flowers are pollinated by flies, bees, and beetles. We studied pollination in different populations of the two European speciesN. lutea andN. pumila in Norway and in Germany. Flowers are self-compatible and protogynous, preventing automatic selfing, and insect pollination is required for seed production. Sympatric populations were studied in Vest-Agder county in Norway to determine whetherN. lutea andN. pumila have the same or different pollinators. Allopatric populations ofN. lutea in Germany and Norway were then compared to determine whether their pollinator spectra differ as would be expected in an open flower with seemingly easily accessible pollen and nectar. Results of the present as well as previous studies of the pollination ofN. lutea andN. pumila show that both species are mainly pollinated by flies, including apparentNuphar specialists, such as the scatophagidHydromyza livens and the ephydridsHydrellia andNotiphila, the last also a long-known pollinator ofN. advena in Florida. Pollinator overlap between sympatric heterospecific populations was small, while allopatric conspecific populations had similar visitor and pollinator spectra. We found no evidence of pollination byDonacia beetles as reported from some North American populations ofNuphar. Dedicated to Univ.-Prof. DrF. Ehrendorfer on the occasion of his 70th birthday     

The floral biology ofThelymitra epipactoides (Orchidaceae), and the implications of pollination by deceit on the survival of this rare orchid

Thelymitra epipactoides has a highly variable visual display achieved through polychromatic flowers and variable inflorescence size, bearing between 7 and 31 flowers, which attract foraging polylectic bees. Only bees of the genusNomia were observed carrying pollinia and successfully pollinating the orchid. The genusNomia contains polylectic, pollen gathering species that store pollen in both the crop and scopa on the hind legs. The absence of a reward for the bees indicates the orchid is relying on deception to attract visitors. The relationship of deception to mimicry is discussed. Once on the flower, tactile, visual and possibly olfactory stimuli direct bees to the false anther formed by the voluminous column wings, where morphological adaptations of the flower ensure that the pollinarium is deposited on the gaster of the bee to effect pollination. — The lack of seed set observed on the Victorian coast appears to be due to the absence of pollinators from the heath and grassland communities in which the orchid grows. This may well be a consequence of the reduced number of plants flowering in the community (a result of the elimination of fire at these sites), thus not maintaining a floral community attractive to potential pollinators.     

A supplementary contribution of ants in the pollination of an orchid, Epipactis thunbergii, usually pollinated by hover flies

It has been controversial how extensively ants contribute to pollination, and we evaluated the contribution of the Japanese carpenter ant, Camponotus japonicus, to the pollination of an orchid, Epipactis thunbergii. Two-year field studies revealed that (1) the ant workers foraged even in cool/cloudy conditions and accordingly visited orchid flowers more frequently (about 40% of all the visitors) than hover flies, the principle pollinators (10–20%), and that (2) the flower-visiting ants occasionally removed pollinia from the anther and then delivered pollen onto the stigmatic surface of other flowers, although self-pollination might frequently occur in the consecutive visits of flowers within an inflorescence. An artificial pollination experiment with pollinia which had been transferred to the ant integument showed that (3) the treated flowers produced as many fruits and seeds as control flowers. We concluded that C. japonicus workers could actually pollinate E. thunbergii flowers and their relative importance as pollinators appeared to be largely dependent on the abundance of flower-visiting workers or weather conditions during the flowering period, which mainly determined the availability of hover flies.     

Deceptive pollination of the Lady's Slipper Cypripedium tibeticum (Orchidaceae)

To test whether the nectarless flowers of Cypripedium tibeticum attract pollinators through mimicry like the allied species C. macranthos var. rebunense, pollination biology of C. tibeticum was investigated in western China. Although C. tibeticum was also pollinated by bumble bee queens, i.e. Bombus lepidus , B. lucorum and B. hypnorum , no special, rewarding model plants were found in the habitat. Field experimentation confirmed that the flowers were self-compatible but insects were required to transfer orchid pollen to the stigma. Both Bombus queens and workers were visitors, but queens were much more frequent than workers and only queens were effective pollinators. Floral functional morphology analysis showed that it was large queens rather than small workers that fitted well with the flowers of C. tibeticum. With the faint sweet-fruity scent, the minor floral fragrance compound, ethyl acetate, probably plays a role in attracting bumble bees by food deception. The dark flowers with the inflated, trap-like labellum are hypothesized to mimic the nest site of queens. Therefore, bumble bee queens tend to be attracted by C. tibeticum through nest site mimic combined with food deception. Considering that the co-blooming flowers of C. flavum are pollinated by the Bombus workers, and C. smithii pollinated by a queen, we suggest that using the same bumblebees with different body sizes as the pollinators is the main reproductive isolation between interfertile C. tibeticum and C. flavum, while C. tibeticum and C. smithii tend to hybridize naturally.     

Pollination biology of Cymbidium goeringii (Orchidaceae) in China

The genus Cymbidium comprises three subgenera with ca. 50 species. Interactions between pollinators and plants have been studied in the two subgenera Cymbidium and Cyperorchis, but only a few studies in the subgenus Jensoa have been reported. Here we report on the reproductive characteristics of C. goeringii (in sub-genus Jensoa) in three populations in the southwest of Hunan Province, China, during the winter from December 2005 to March 2006. Floral phenological and morphological features, behavior of visitors, the breeding system, and fruit sets under natural conditions were studied. The flowers of C. goeringii were strongly fragrant, but did not present any rewards to the visitors. The flowering period of C. goeringii in the studied populations lasted about 40 days, and most flowers (about 60%) opened within 30 days. Flowers opened immediately when temperature increased obviously and reached to about 16 ℃. The flowering time of the pollinated flowers, unpollinated flow-ers and the flowers with pollinarium removed were similar. Two bees of Apidae, Apis cerana cerana (honeybee) and Anthophora melanognatha, were observed visiting flowers of C. goeringii, but only the honeybees performed as pollinators. The honeybees mostly visited the orchid flowers at 10:00–17:00 on sunny days with temperature above 10 ℃. A total of only thirteen visits were observed during 20 days of observation, indicating pollinators were rare. Honeybees directly landed on the upper surface of the labellum and inserted their heads into the flowers between column and labellum, while the hind legs trod on the surface of the curved downward mid-lobe of label-lum. When a honeybee landed on the labellum of a flower, the labellum moved up and down slightly. After the honeybee entered the flower further, its head might touch the foot of the column. At this time, the body of the honeybee was parallel with the upper surface of the labellum. Then the honeybee used its front legs to scratch on the callus ridges on the upper surface of the labellum, and its hind legs hooked the edges of the side lobe of label-lum, trying to exit forcibly from the flower. During exiting process, sometimes the honeybee’s body was arched owing to tension. In this case, the surface of the scutellum came into close contact with the viscidium and then pollinaria, together with the anther cap, were removed. When this honeybee visited next flower, the pollinaria would be adhered to the stigma when it arched its body during the exiting process. Three plant species flowered synchronously with C. goeringii in the studied areas, but their flowers were different with C. goeringii in color or shape. Because C. goeringii is rewardless to pollinators, the flowers probably attract visitors by olfactory stimu-lus. Breeding system experiments showed no spontaneous autogamy and pollination success relying on pollinators in C. goeringii. Artificial pollination resulted in 90% fruit set by induced autogamy, 100% by pollinating within clone, and 100% by xenogamous pollination, respectively. These results indicate that C. goeringii is highly self-compatible and the fruit production is pollen limited. Because pollinators are essential for fruit set of C. goeringii in natural habitats, protection of wild honeybee populations or apiculture is likely a simple but effective strategy to maintain the orchid populations.     

A new species of Ponthieva (Orchidaceae, Cranichidinae) from Veracruz, Mexico

Ponthieva rinconii, a new orchid species from the foothills of the Sierra Madre Oriental in Veracruz, Mexico, is described and illustrated. It is similar in overall appearance to the wide-ranging upland speciesP. schaffneri, but differs from it in habitat preferences (tropical semi-evergreen forest at 650 m elevation), presence of a loose raceme, and three-lobed labellum with a basal cavity.     

Pollination of Campanula rapunculus L. (Campanulaceae): How much pollen flows into pollination and into reproduction of oligolectic pollinators?

We studied an isolated population of Campanula rapunculus and two oligolectic bee species of Chelostoma (Megachilidae), their main pollinators. The population of C. rapunculus consisted of 2808 plants. Measurements of pollen flow showed that 3.7% of the pollen produced by a flower contribute to pollination, 95.5% was collected by bees for their offspring and 0.8% remained on the styles. Pollen analyses of brood cells of Chelostoma rapunculi revealed that females collected on average 4.9 million Campanula pollen to rear one bee. We calculated that approximately 1588 bees of this species could have been reared at the study site during the studied season. The amount of potentially viable pollen deposited on stigmas was 3.6 to 10.7 times higher than the number of ovules. We discuss morphological features of the flowers which may lower the pollen removal rate per bee visit and consequently cause a high visitation and pollination rate.The study was supported by a joint project CAPES / DAAD (Probral 112/00). We thank NaBu (Naturschutzbund) Bonn and the Untere Landschaftsbehörde Siegburg for the permission to work at the Natural Reserve Dünstekoven.     

Pollination biology ofSymphonia globulifera (Clusiaceae)

The pollination biology ofSymphonia globulifera was studied in Central Amazonia, Brazil. As suggested by the bird syndrome of the flowers, these are mainly pollinated by hummingbirds. Occasional visits by other birds, butterflies and more rarely bees, as well as tamarin monkeys were also observed.Trigona bees partly destroy the flower tube to rob nectar. The possibility thatS. globulifera may not be primarily adapted to hummingbird pollination is discussed. The pollen is intermixed in an oily fluid secreted by the anthers (antheroil). Each of the five stigmas consists of a pore-like opening at the apex and a small chamber behind it. The antheroil mixed with pollen is absorbed by capillarity into the chamber when deposited on the pore. the pollen germinates inside the stigma. The presence of antheroil and pore-like stigmas in the flowers of the closely relatedPlatonia insignis indicate a similar mode of pollination. The results of this study are compared with observations in some otherClusiaceae (Caraipa, Clusia, Garcinia, Mahurea), where floral oils or floral resin occur. The role of these substances in the pollination process and their relation to the evolution of flower biology inClusiaceae are briefly discussed.     

Sexual mimicry in Mormolyca ringens (Lindl.) Schltr. (Orchidaceae: Maxillariinae)

BACKGROUND AND AIMS: Pollination through sexual mimicry, also known as pseudocopulation, has been suggested to occur in some genera of the Neotropical orchid subtribe Maxillariinae. However, it has been demonstrated so far only for Trigonidium obtusum. This study reports and illustrates pollination through sexual mimicry in Mormolyca ringens. METHODS: A total of 70 h were dedicated to the observation of flowers and pollinator behaviour, which was photographically recorded. Flower features involved in pollinator attraction were studied using a stereomicroscope and by SEM analyses. Preliminary observations on the plant breeding system were made by manually self-pollinating flowers. The chemical composition of the fragrance volatiles was determined by GC/MS analysis. KEY RESULTS: The flower features of M. ringens parallel those of other pseudocopulatory flowers. The labellum shape and indument are reminiscent of an insect. Sexually excited drones of Nannotrigona testaceicornis and Scaptotrigona sp. (both in the Apidae: Meliponini) attempt copulation with the labellum and pollinate the flower in the process. In both bee species, the pollinarium is attached to the scutellum. Pollinator behaviour may promote some degree of self-pollination, but preliminary observations indicate that M. ringens flowers are self-incompatible. Flowers are produced all the year round, which ties in with the production of bee males several times a year. The phylogenetic relationships of M. ringens are discussed and a number of morphological and phenological features supporting them are reported. CONCLUSIONS: It is expected that further research could bring to light whether other Maxillariinae species are also pollinated through sexual mimicry. When a definitive and robust phylogeny of this subtribe is available, it should be possible to determine how many times pseudocopulation evolved and its possible evolutionary history.     

Pollination of the European food-deceptive Traunsteinera globosa (Orchidaceae): the importance of nectar-producing neighbouring plants

European food-deceptive orchids generally flower early in spring and rely on naïve pollinators for their reproduction. Some species however, flower later in the summer, when many other rewarding plants species are also in bloom. In dense flowering communities, deceptive orchids may suffer from competition for pollinator resources, or might alternatively benefit from higher community attractiveness. We investigated the pollination strategy of the deceptive species Traunsteinera globosa, and more specifically whether it benefited from the presence of coflowering rewarding species. We carried out a population survey to quantify the density and reproductive success of the orchid as well as the density of all coflowering species. Our results suggest that the deceptive orchid not only benefited from the presence of coflowering species, but that interestingly the density of the species Trifolium pratense was significantly positively correlated with the orchid's reproductive success. This species might simply act as a magnet species attracting pollinators near T. globosa, or could influence the orchid reproductive fitness through a more species-specific interaction. We propose that morphological or colour similarities between the two species should be investigated in more detail to decipher this pollination facilitation effect.