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Floral diversity within Miconieae, exemplified by species with variable floral traits. A, Clidemia capitellata. B, Clidemia ciliata. C, Charianthus purpureus. D, Maieta poeppigii. E, Anaectocalyx bracteosa. F, Leandra australis. G, Miconia ampla. H, Miconia cernua. I, Mecranium haemanthum. J, Conostegia macrantha. K, Miconia affinis. L, Pachyanthus pedicellatus. M, Miconia cerasiflora. N, Miconia aureoides. O, Miconia brachycalyx. P, Miconia corymbiformis. Scale bars p 5 mm.
Contexts in source publication
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... it was well sampled. Analyses were run for 80 million generations, sampling every 7000 generations, with the first 10% of samples discarded as burn-in. To address potential sensitivity of the results to the prior on the expected number of shifts ( Moore et al. 2016), we tested several priors and, as the analyses were robust to prior choice ( fig. S1, available online), set the prior on expected number of shifts to 10 (as suggested by BAMMtools for a phylogeny of this size; Rabosky et al. 2014). The best rate shift configuration was obtained with the maximumShiftCredibility function in ...
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... of field photographs of more than 350 Miconieae species has confirmed the striking variability in floral traits for a tribe with conserved flower morphology (app. 2A, 2B; supplementary material VII; fig. 1). Petal and anther colors varied among white, yellow, and either pink or purple, which allowed for many different color combinations across the tribe. Variability of the shapes, positions, and sizes of reproductive organs allowed for various phenotypes, with variation in forms of symmetry. While many species had herkogamous flowers, ...
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... Variability of the shapes, positions, and sizes of reproductive organs allowed for various phenotypes, with variation in forms of symmetry. While many species had herkogamous flowers, the same effect (separation between stigma and anthers) was achieved through various combinations of anther and stigma positions, shapes, and lengths (compare fig. 1F, 1J, ...
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... almost three-quarters of all species studied and were represented in nearly every clade within the phylogeny. Species within two large clades (Miconia and Cremanium) had predominantly white petals. Yellow petals were very rare and appeared in only six species (two closely related species within Miconia, one in Caribbean, and three in Cremanium; fig. 1H, 1P). Yellow petals seem to have evolved from white ...
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... color was a more labile character than petal color. Most of the clades contained all three phenotypes, although pink, purple, or blue anthers were less frequent ( fig. 2). White anthers were more common in Miconia ( fig. 1K) and Clidemia ( fig. 1A), while nearly all species within Caribbean Miconieae and Conostegia had yellow anthers ( fig. 1J). Ancestral state reconstructions suggested that white anthers had evolved from colorful anthers (either pink or ...
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... color was a more labile character than petal color. Most of the clades contained all three phenotypes, although pink, purple, or blue anthers were less frequent ( fig. 2). White anthers were more common in Miconia ( fig. 1K) and Clidemia ( fig. 1A), while nearly all species within Caribbean Miconieae and Conostegia had yellow anthers ( fig. 1J). Ancestral state reconstructions suggested that white anthers had evolved from colorful anthers (either pink or ...
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... color was a more labile character than petal color. Most of the clades contained all three phenotypes, although pink, purple, or blue anthers were less frequent ( fig. 2). White anthers were more common in Miconia ( fig. 1K) and Clidemia ( fig. 1A), while nearly all species within Caribbean Miconieae and Conostegia had yellow anthers ( fig. 1J). Ancestral state reconstructions suggested that white anthers had evolved from colorful anthers (either pink or ...
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... when broad and rimose pores were grouped together so that pore size could be converted into a binary character (two character states: minute pores and large pores). Large pores were more common in flowers with polysymmetric anthers, a straight upward style, and a lack of anther/petal contrast (especially when both anthers and petals were white; fig. 1K, 1P). Such a phenotype was found in 15% of all species and appeared in multiple instances across three clades (Miconia, Cremanium, and Mecranium). These findings were supported by Pagel's correlation test, which showed significant correlation between 10 out of 15 pairs of examined binary characters (table 1). On the other hand, Pagel's ...
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... petal and anther sizes covary, with integrated evolutionary trends in floral size ( fig. 5). In Clidemia and several subclades of Miconia, petal size decreased or remained the same with a simultaneous increase in anther length, resulting in a peculiar floral phenotype with long, often colorful anthers and small, pale, and often reflexed petals ( fig. 1B, 1F, 1G, ...
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... along branches detected nine diversification rate shifts (fig. 6). The oldest shift occurred approximately 17 mya, near the most recent common ancestor of the tribe Miconieae, and denotes the split between the clade of Eriocnema and Physeterostemon (four samples in this phylogeny out of seven known species) and the radiation of the Miconieae ( fig. 6; shift 1). The second shift occurred 12 mya at the node representing the most recent common ancestor of a clade that includes Conostegia, Cremanium, and the Caribbean clades (shift 2). Diversification rates within this group increased and remained higher than those of the rest of the tribe, except for clades with more recent diversification ...
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... conclude that the ancestral flower likely had white petals and colorful anthers and displayed monosymmetry in both the androecium and the gynoecium. It was likely herkogamous, had a curved style directed away from the center of the flower, and had monosymmetric stamens with minute anther pores (see fig. 1G, 1L for such color and shape combinations). Such floral features are commonly observed in Melastomataceae, although yellow anther color is more widespread than pink or purple (Renner 1989;Larson and Barrett 1999). This phenotype is consistent with morphological specialization toward buzz pollination by bees, which is the predominant ...
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... shifts to a different specialized pollination mode by hummingbirds, especially when brightly colored pink or deep-red petals form a tubular shape in a mature flower ( Varassin et al. 2008). Such pollination has been observed in several nectariferous species of Miconieae ( Judd 2003, 2005;Goldenberg et al. 2008; e.g., see Charianthus purpureus in fig. 1C). Yellow petals were observed in only a few species, and they often either were short and inconspicuous or lacked anther/petal contrast, suggesting that yellow pigment in these species would not be an effective attractive cue for bee pollinators. However, as a contrasting backdrop to brightly colored anthers (Lunau 2006) or in shaded ...
Citations
... The genus is generally defined by terminal or axillary inflorescences, flowers subtended by a single pair of bracteoles, anthers without pedoconnectives, and berry fruits (Michelangeli et al. 2022). Because of its diversity of sexual and asexual repro-ductive strategies, the genus has been increasingly used to investigate shifts in pollination systems, floral trait evolution, and asexual reproduction via apomixis (Goldenberg and Shepherd 1998;Goldenberg et al. 2008;Caetano et al. 2013Caetano et al. , 2018de Brito et al. 2016;Gavrutenko et al. 2020). The occurrence and distribution of dioecy in Miconia, however, has been overlooked and ill defined. ...
... The disjunct distribution of dioecism, coupled with such variable floral morphology among species, alludes to multiple evolutionary origins of dioecy in Miconia, in contrast to previous suggestions of a single-origin scenario (Almeda and Dorr 2006). Although the most recent phylogenies of Miconia (Goldenberg et al. 2008;Gavrutenko et al. 2020) lack adequate sampling and resolution for the majority of these dioecious species, they indicate independent evolution of dioecy in the Andes and Central America, with dioecious species endemic to each region being interspersed throughout the phylogenies and nested within different and otherwise hermaphroditic clades. The different staminate floral morphologies (types Ia-Ic), however, do not seem to be conserved within specific clades. ...
... Additionally, rather than the small apical pores suitable only to releasing pollen at a certain buzzing frequency, the anther pores in Miconia section Cremanium are larger and more suitable for pollen transfer onto nonbuzzing insects. This specialist to generalist shift in pollination is not unprecedented in Miconia (de Brito et al. 2016;Gavrutenko et al. 2020) and may be facilitating the success of dioecious Miconia in higher-elevation montane habitats. Unfortunately, formal documentations of pollinator observations, pollen-release mechanisms, and pollen-reward mechanisms are lacking in all dioecious Miconia. ...
... In the first half of the 20th century, studies on the genetics of plant reproductive systems began to be highlighted, making evident the micro-and macroevolutionary consequences and their influences on taxonomy (Barrett 2010). Recently, phylogenetic comparative methods have become useful for understanding the evolutionary history and correlation of reproductive traits, allowing the association with environmental and ecological data (Murúa and Espíndola 2015, Ohashi et al. 2015, Brito et al. 2016, Bawa et al. 2019, Bogarín et al. 2019, Gavrutenko et al. 2020, Koski 2020, Melo et al. 2021, Rose and Sytsma 2021. ...
Studies about reproductive aspects of angiosperms rarely refer to herbaceous and anemophilous groups. Cyperaceae are cosmopolitan and diverse in terms of sexuality, inflorescence architecture, and pollination modes, such as anemophily, entomophily, and ambophily. Therefore, the evolution of reproductive traits can clarify some questions about the reproductive biology of angiosperms, especially regarding the transitions between biotic and abiotic pollination. This study was designed to investigate the evolution of reproductive traits in Cyperaceae through comparative phylogenetic methods, such as reconstruction of ancestral states and evolutionary correlation. If spicoids in Mapanioideae are indeed inflorescences, the bisexual flower in Cyperaceae would be derived, a rare case in angiosperms. In Cyperoideae, a decrease in the number of flowers and an increase in stamen loss events were observed. This result contradicts the hypothesized increase in reproductive structures in anemophilous species, in which a greater amount of pollen is produced to compensate for the waste generated by wind. Only one correlation was found: between the number of inflorescence branches and the number of reproductive units per inflorescence. Finally, the analyses showed the great diversity of reproductive biology in Cyperaceae and made evident the need to expand the theoretical studies to refine the discovery of correlated traits.
... Previous work Gavrutenko et al., 2020) suggested that the Caribbean clade was most likely to be closely related to a Central American group, the Conostegia clade of ~75 species (Kriebel, 2016), and was likely to be derived from a Central American ancestor, although it is unclear when and where the most recent common ancestor of the Caribbean clade might have established in the Caribbean region . Michelangeli et al. (2022b) suggested that a more robust dataset would be necessary to test biogeographical patterns among the islands. ...
... We sampled broadly across the Caribbean clade, including members from all previously known, major subclades (Michelangeli et al., 2004;Goldenberg et al., 2008;Gavrutenko et al., 2020). This also included a number of Caribbean clade taxa never before sampled for phylogenetic analyses (N = 15), (Majure et al., 2022c) and Miconia sp. 2 (L.C. ...
... The Caribbean clade was well supported as sister to a large clade consisting of the Conostegia clade and Mexican Octomeris/Amblyarrhena, which were also included in the Conostegia clade by Michelangeli et al. (2022b), and members of the Cremanium clade, which included the Greater Antillean Chaenopleura clade nested within (Supporting Information, Fig. S1). Thirteen clades were resolved within the Caribbean clade, mostly corresponding to previously recognized major subclades (see Fig. 2; also see Supporting Information, Gavrutenko et al., 2020) were resolved in our analysis of plastome data (Fig. 2). The Pachyanthus and Miconiastrum subclades were well supported as sister here [bootstrap support (BS) = 100], whereas previously the position of those subclades was unsupported (e.g. ...
The Greater Antilles are renowned as a biodiversity hotspot and known to be geologically complex, which has led, in part, to the generation of organismal diversity in this area. One of the most species-rich montane groups within the Greater Antilles is the tribe Miconieae (Miconia s.l.) of the Melastomataceae, with ca. 325 species found there. The most diverse clade of Miconia in the Caribbean, the Caribbean clade, composes roughly half of that diversity, with an estimated 160 species, nearly all of which are endemic to the Greater Antilles. It is unclear how that diversity has been generated through time or where it originated, but we now have sufficiently well-sampled and robust datasets to test these patterns. Using a custom-built plastome dataset, we generated a robust phylogenetic hypothesis for 106 of the 160 Caribbean clade members and tested biogeographical patterns among the islands. Our results suggest that the Caribbean clade originated in the mid-Miocene, probably from a South American ancestor, and diversified substantially on the island of Cuba before repeatedly dispersing across other parts of the Greater Antilles, especially into nearby Hispaniola and then, to a lesser extent, into Jamaica, Puerto Rico and, finally, into the Lesser Antilles.
... Previous work Gavrutenko et al., 2020) suggested that the Caribbean clade was most likely to be closely related to a Central American group, the Conostegia clade of ~75 species (Kriebel, 2016), and was likely to be derived from a Central American ancestor, although it is unclear when and where the most recent common ancestor of the Caribbean clade might have established in the Caribbean region . Michelangeli et al. (2022b) suggested that a more robust dataset would be necessary to test biogeographical patterns among the islands. ...
... We sampled broadly across the Caribbean clade, including members from all previously known, major subclades (Michelangeli et al., 2004;Goldenberg et al., 2008;Gavrutenko et al., 2020). This also included a number of Caribbean clade taxa never before sampled for phylogenetic analyses (N = 15), (Majure et al., 2022c) and Miconia sp. 2 (L.C. ...
... The Caribbean clade was well supported as sister to a large clade consisting of the Conostegia clade and Mexican Octomeris/Amblyarrhena, which were also included in the Conostegia clade by Michelangeli et al. (2022b), and members of the Cremanium clade, which included the Greater Antillean Chaenopleura clade nested within (Supporting Information, Fig. S1). Thirteen clades were resolved within the Caribbean clade, mostly corresponding to previously recognized major subclades (see Fig. 2; also see Supporting Information, Gavrutenko et al., 2020) were resolved in our analysis of plastome data (Fig. 2). The Pachyanthus and Miconiastrum subclades were well supported as sister here [bootstrap support (BS) = 100], whereas previously the position of those subclades was unsupported (e.g. ...
... Such apparent generalization in pollination is common in plants with traditional syndromes (Ollerton et al., 2009). In concert with the recognition that the floral traits might evolve in response to selective pressure exerted by multiple pollinators and antagonists (Aigner, 2001), the idea of a pollination syndrome is considered to include not only specialization for primary pollinators but adaptive generalization towards other visitors (Dellinger et al., 2019;Gavrutenko et al., 2020;Ohashi et al., 2021). As discussed in the previous section, floral traits of fungus gnat-pollinated Euonymus plants might reflect either adaptation to attract the primary pollinator fungus gnats and/or to discourage visitation by non-beneficial insects. ...
Background and aims:
Dipteran insects are known pollinators of many angiosperms, but knowledge on how flies affect floral evolution is relatively scarce. Some plants pollinated by fungus gnats share a unique set of floral characters (dark red display, flat shape and short stamens), which differs from any known pollination syndromes. We tested whether this set of floral characters is a pollination syndrome associated with pollination by fungus gnats, using the genus Euonymus as a model.
Methods:
The pollinator and floral colour, morphology and scent profile were investigated for ten Euonymus species and Tripterygium regelii as an outgroup. The flower colour was evaluated using bee and fly colour vision models. The evolutionary association between fungus gnat pollination and each plant character was tested using a phylogenetically independent contrast. The ancestral state reconstruction was performed on flower colour, which is associated with fungus gnat pollination, to infer the evolution of pollination in the genus Euonymus.
Key results:
The red-flowered Euonymus species were pollinated predominantly by fungus gnats, whereas the white-flowered species were pollinated by bees, beetles and brachyceran flies. The colour vision analysis suggested that red and white flowers are perceived as different colours by both bees and flies. The floral scents of the fungus gnat-pollinated species were characterized by acetoin, which made up >90 % of the total scent in three species. Phylogenetically independent contrast showed that the evolution of fungus gnat pollination is associated with acquisition of red flowers, short stamens and acetoin emission.
Conclusions:
Our results suggest that the observed combination of floral characters is a pollination syndrome associated with the parallel evolution of pollination by fungus gnats. Although the role of the red floral display and acetoin in pollinator attraction remains to be elucidated, our finding underscores the importance of fungus gnats as potential contributors to floral diversification.
... Accordingly, in Melastomataceae species specialized for buzz pollination (ca. 96%; Dellinger et al., 2022), androecia are usually zygomorphic, while reversals to actinomorphy often associate with more generalized (non-buzz) pollination (Gavrutenko et al., 2020;Judd et al., 2022). Keeping the generally messy pollen deposition of buzz pollination in mind (but see Konzmann et al., 2018 on precise pollen placement), however, the full value of zygomorphy can only be appreciated when simultaneously considering aspects of herkogamy and pollination accuracy. ...
... Finally, aspects of herkogamy also differ from systems with openly exposed pollen and passive pollen transfer since the pore does not necessarily represent the site of pollen placement on the pollinator. In relation to herkogamy, it is interesting to note that anther pores are usually directed away from the stigma, possibly a mechanism to reduce self-pollen deposition (Gavrutenko et al., 2020). Taken together, we argue that, while androecial zygomorphy (achieved by the position of the colorful appendages) is important in forcing bees into optimal buzzing positions, appendage-stigma distance and appendage-pore distance, combined with pollinator size and behavior and herkogamy, are critical determinants of realized pollination accuracy and reproductive success in Melastomataceae flowers with prominent stamen appendages. ...
Premise:
Floral shape (relative arrangement and position of floral organs) is critical in mediating fit with pollinators and maximizing conspecific pollen transfer particularly in functionally specialized systems. To date, however, few studies have attempted to quantify flowers as the inherently three-dimensional (3D) structures they are and determine the effect of intraspecific shape variation on pollen transfer. We here addressed this research gap using a functionally specialized system, buzz pollination, in which bees extract pollen through vibrations, as a model. Our study species, Meriania hernandoi (Melastomataceae), undergoes a floral shape change from pseudocampanulate corollas with more actinomorphically arranged stamens (first day) to open corollas with a more zygomorphic androecium (second day) over anthesis, providing a natural experiment to test how variation in floral shape affects pollination performance.
Methods:
In one population of M. hernandoi, we bagged 51 pre-anthetic flowers and exposed half of them to bee pollinators when they were in either stage of their shape transition. We then collected flowers, obtained 3D flower models through x-ray computed tomography for 3D geometric morphometric analyses, and counted the pollen grains remaining per stamen (male pollination performance) and stigmatic pollen loads (female pollination performance).
Results:
Male pollination performance was significantly higher in open flowers with zygomorphic androecia than in pseudo-campanulate flowers. Female pollination performance did not differ among floral shapes.
Conclusions:
These results suggest that there is an "optimal" shape for male pollination performance, while the movement of bees around the flower when buzzing the spread-out stamens results in sufficient pollen deposition regardless of floral shape.
... We set a relaxed log-normal molecular clock for each locus, using hyperparameters to estimate substitution rates (Drummond et al., 2006). We assumed the calibrated Yule model for tree topology, and we set two secondary calibration points by Gavrutenko (2020): (1) the last common ancestor of Eriocnema+Phyeseterostemon+Miconia (14.71-29.9 Mya); and (2) the Miconia crown [Miconia IV + Miconia V groups in Goldenberg et al. (2008)] (7.05-13.44 ...
Background and aims:
The evolution of ecological specialization is favoured under divergent selection imposed by increased environmental heterogeneity, while specialization can limit organisms' geographic range, thus promoting endemism. The Atlantic Forest (AF) is an ancient montane domain with high plant endemism, holding different environments for plant specialization. Miconia is the most diverse genus of woody flowering plants within the AF domain, including AF-endemic and non-endemic lineages. We hypothesized that Miconia species have faced increased environmental heterogeneity and consequently have been selected towards increased specialization in the AF domain, and such an increased specialization has greatly reduced species' geographic range, ultimately promoting endemism. Hence, we predicted that (1) AF-endemic species should face greater environmental heterogeneity than non-endemic species; (2) AF-endemic species should be more specialized than non-endemic species; (3) specialization should lead to smaller geographic ranges; (4) specialization and small geographic ranges among AF-endemic species should conform to a selection-driven evolutionary scenario rather than to a neutral evolutionary scenario; and (5) small geographic ranges among AF-endemic species should date back to the occupation of the AF domain rather than to more recent time periods.
Methods:
We utilized geographic, environmental, and phylogenetic data on a major Miconia clade including AF-endemic and non-endemic species. We calculated Rao's Q to estimate the environmental heterogeneity faced by species. We utilized geo-referenced occurrences to estimate species' geographic range. We applied environmental niche modelling to infer species' niche breadth. We inferred the most likely evolutionary scenario for species' geographic range and niche breadth via a model-fitting approach. We utilized ancestral reconstructions to evaluate species' geographic range throughout time.
Key results:
AF-endemic species faced from 33 to 60% more environmental heterogeneity whose increase was associated with AF's montane landscapes. AF-endemic species were overall 60% more specialized, specifically over highly variable environmental gradients in AF's montane landscapes. Specialization strongly predicted small geographic ranges among AF-endemic species, being a major range-limiting factor among endemic lineages. AF-endemic species have evolved towards specialization and small geographic ranges under a selection-driven regime, likely imposed by the great environmental heterogeneity in AF's montane landscapes. AF-endemic species underwent a major reduction of geographic range right after their evolution, indicating a long-standing effect of selective pressures in the AF domain.
Conclusion:
Environmental heterogeneity imposes selective pressures favouring ecological specialization and small geographic ranges among plant lineages in the AF domain. This selection-driven process has likely promoted plant endemism in the AF domain throughout the historical periods.
... The results presented here are taken directly from the tribe-wide analysis of the Miconieae by Gavrutenko & al. (2020). This study included 1083 species of Mico nieae across all morphological groups and spanning the geographical distribution of the tribe. ...
... & Hook. f. and a group of species of Miconia formerly in Clidemia D. Don (the "globuliflora" group) ( Fig. 1; for details see Gavrutenko & al. 2020). These analyses also confirmed that M. deli catula, another Cuban species with deciduous leaves but different anther morphology and placentation, although part of the Caribbean clade, is not part of M. sect. ...
... The oldest name in the clade is Miconia thomasiana, described by Candolle (1828) Gavrutenko & al. (2020). Black circles denote nodes with 100% bootstrap support; grey circles denote nodes with 85-99% bootstrap support; nodes with open circles denote 50-84% bootstrap support. ...
Phylogenetic analyses show that a group of species of Miconia (Melastomataceae: Miconieae) from the Greater Antilles
all form a clade. They share the presence of backward-deflexed filaments with the entire androecium turning pink to red after
anthesis and placentation reduced axile to basal. Additionally, many of these species are deciduous, and have fruits with few and relatively large seeds. These species have until recently been recognized in Calycogonium, Miconia, Ossaea and Pachyanthus.
The group is composed of 14 species, two from Puerto Rico and 12 from Cuba, including the newly described M. matosiana. We
formally describe this clade as M. sect. Liogieria and provide a revision of its species, including an identification key, descriptions,
maps and photographs or illustrations for all of them. Twelve names are typified: Calycogonium clidemioides Griseb., C.
rosmarinifolium Griseb., Charianthus obliquus Griseb., Graffenrieda obtusa Griseb., Miconia baracoensis Urb., M. cerasiflora Urb., M. cerasiflora var. setulifera Urb., M. confusa Cogn., M. obtusa f. glabrior Urb., M. pachyphylla Cogn., M.
thomasiana DC.and M. vernicosa Naudin.
... A diferencia de la fructificación, la floración de estas dos especies ocurre en las temporadas más secas del área de estudio (diciembre-abril), resultados que se corroboran con los obtenidos por Manrique et al. (2022) para M. elaeoides, y que pueden estar directamente correlacionados con una mayor abundancia y riqueza de insectos (Hymenoptera y Díptera). No obstante, Brito et al. (2017) proponen esta relación en Microlicieae y Melastomeae, cuyas especies son melitofílicas y dependen de polinizadores especializados para su reproducción, y no en Miconieae, donde los pétalos blancos no funcionan en la atracción de polinizadores, hay producción de néctar y reproducción por apomixia (Gavrutenko et al., 2020;Manrique et al., 2022). Aunque la floración de especies de Miconia en meses secos no está totalmente determinada por la abundancia de polinizadores, puede ser resultado de la alta demanda de agua para la producción de frutos; de modo que, es necesario florecer en estos tiempos, para que la fructificación coincida con las épocas más lluviosas (Brito et al., 2017), y se favorezca el desarrollo de los frutos carnosos, acuosos y ricos en azúcar propios de estas especies (Maruyama et al., 2019). ...
... Las flores y frutos de las dos especies objeto de estudio presentan diferencias en su forma y tamaño, sin embargo, al igual que en otras especies de Miconia miden ~5 mm, con pétalos y anteras blanco-amarillas (Dellinger et al., 2022), característica aparentemente ancestral, que dio lugar a flores más coloridas polinizadas por abejas (Gavrutenko et al., 2020). Las flores de M. elaeoides tienen una longitud (4.88 ± 0.38 mm) mayor que las de M. ligustrina (2.62 ± 0.35 mm), en M. elaeoides las flores son más largas que anchas, en M. ligustrina más anchas que largas. ...
... Los poros de las anteras, más largos que anchos en las dos especies, son más grandes en M. elaeoides. Estas diferencias morfométricas entre las dos especies, junto con las variaciones en la forma e indumento, probablemente sean cambios evolutivos direccionados por presiones selectivas como competencia por polinizadores y modos de polinización, que permitieron la diversificación actual de Miconia (Gavrutenko et al., 2020;Goldenberg et al., 2008). Asimismo, la variación morfológica observada entre las especies de estudio demuestra las múltiples interacciones con polinizadores sin síndrome de zumbido, que posiblemente están ocurriendo al interior del género (Gavrutenko et al., 2020). ...
Introducción:
El Páramo es uno de los ecosistemas más afectados por actividades humanas, lo que aumenta la necesidad de estudios fenológicos como base para el manejo y la conservación.
Objetivo:
Describir la feno-morfología de Miconia ligustrina y Miconia elaeoides.
Métodos:
De septiembre 2019 a febrero 2020, y de abril 2021 hasta agosto del mismo año, se monitoreó la fenología de 12 individuos de cada especie. Adicionalmente, se vincularon datos fenológicos de ejemplares de herbario, para corroborar los resultados obtenidos. En los dos conjuntos de datos, se describió su distribución usando estadística circular, además, se obtuvieron registros de precipitación y temperatura del área. Adicionalmente, se describió la morfometría de cada especie.
Resultados:
El pico de floración de M. lingustrina es en abril, y la fructificación se concentra entre junio y julio; M. elaoides, florece de forma masiva en enero, con la máxima producción de frutos en mayo. Hubo correlación entre fenología y lluvias: la floración se da en época seca y la fructificación en la época lluviosa. Las especies difieren en morfología, pero, como en otras especies de Miconia, las flores y frutos son pequeños (aprox. 5 mm).
Conclusión:
La floración se presenta en la época seca y la fructificación en la época lluviosa, cuando las tasas de fotosíntesis son bajas y la frugivoría incrementa. Este patrón fenológico favorece la dispersión óptima de semillas.
... In the case of phenotypic trade-offs, adaptation to multiple pollinator groups can be achieved by changing single floral traits (allowing the secondary pollinator to contribute to pollen transfer) without changing the fundamental phenotype adapted to the main pollinator. By mitigating the disadvantages of trade-offs, species may achieve "adaptive generalization" (Ohashi et al., 2021) as described in recent publications (Armbruster, 2014;Cairampoma et al., 2020;Dellinger et al., 2019;Gavrutenko et al., 2020). ...
Many plants exhibit floral traits that are directed to specific pollinator groups. Nevertheless, they can also attract less‐adapted pollinators and gain benefits under certain conditions, resulting in adapted generalization. This may be the case in Salvia daiguii (Lamiaceae), an endangered, bee‐pollinated species native to the Tianmenshan National Forest Park, China. The flower appears phenotypically specialized to bees but is also visited by Macroglossum bombylans. In the present study, we test whether the moth is an effective pollinator of S. daiguii . We quantified and compared the frequency of flower visits by bees and moths and the number of pollen grains deposited on the stigma after a single visit. We also recorded the movements of pistils and stamens of S. daiguii and the behavior of the hawkmoth at the flowers. We found that Apis cerana was the predominant pollinator, depositing an average of 4.74 pollen grains on the stigma after a single visit. However, as the style bends downward during anthesis and reaches the same level as the anthers, Macroglossum individuals hovering around the flowers were also able to effectively transfer pollen to the stigma. On average, 1.38 pollen grains were deposited on the stigma during a single visit. We demonstrate for the first time that the hawkmoth is an effective secondary pollinator in the primarily bee‐pollinated S. daiguii . Style bending allows a nectar thief to become a secondary pollinator. The extent of pollinator generalization is thus increased without affecting the fundamental phenotype adapted to bees as the main pollinators.
