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Variation in fruits in Episcieae. A, Fleshy display capsule in Nematanthus albus. B, Fleshy display capsule in Drymonia chiribogana. C, Indehiscent fleshy berry in Paradrymonia metamorphophylla. D, Semifleshy capsule in Paradrymonia ciliosa. E, Dry capsule in Episcia xantha. F, Semifleshy capsule in Episcia lilacina. G, Dry capsule showing splash-cup seed dispersal in Lembocarpus amoenus. H, Semifleshy capsule in Nautilocalyx panamensis. (Voucher specimens at US: B, J. L. Clark 7358; C, J. L. Clark 9874; D, J. L. Clark 6791; E, J. L. Clark 11323; F, J. L. Clark 1259; G, J. L. Clark 8841; H, J. L. Clark 12735. Photos: A by Jiri R. Haager, B–G by John L. Clark, and H by James F. Di Loreto.)
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The Gesneriaceae is a family known for convergent evolution of complex floral forms. As a result, defining genera and resolving evolutionary relationships among such genera using morphological data alone has been challenging and often does not accurately reflect monophyletic lineages. The tribe Episcieae is the most diverse within Neotropical Gesne...
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Plagiothecium longisetum was described by Lindberg in 1872, based on Maximowicz materials from Japan. In the 1970s, this species was synonymized with P. nemorale. However, a polyphasic approach applied to the investigation of the P. nemorale sensu lato showed a clear separation between the specimens of former P. longisetum and the type of P. nemora...
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... The analyses by Clark et al. (2006), Clark et al. (2012), and Mora and Clark (2016) pointed out the need for taxonomic reorganization for the clade composed of Paradrymonia, Nautilocalyx, and Chrysothemis since these are probably non-monophyletic genera, and the morphology of the pollen grains of their species can be used, together with other data, to assist the taxonomy of the group. Thus, other studies involving the palynology of Columneinae may clarify the taxonomic relationships of the subtribe. ...
Columneinae, a morphologically diverse Neotropical group of Gesneriaceae, is strongly supported as a monophyletic, but many of the genera are weekly supported and lack diagnostic characters at the generic level. Predominantly distributed in the Andes and Amazon biomes, this group has not been evaluated from a palynological context. To address this gap and initiate comprehensive pollen studies within Columneinae, we conducted analyses on 28 species belonging to the genera Centrosolenia Benth., Chrysothemis Decne., Columnea L., Drymonia Mart., Glossoloma Hanst., Lesia J.L.Clark & J.F.Sm., Nautilocalyx Linden., and Trichodrymonia Oerst. Pollen grains were subjected to acetolysis, measurement, and light microscopy, with select species also examined under scanning electron microscopy. Quantitative data underwent statistical analysis tailored to the sample size and multivariate analysis. Variability was observed in size, shape, aperture type, aperture number, ectoaperture length, endoaperture shape, and exine ornamentation. The diverse morphological features led to the identification of distinct pollen types within Columneinae clades. Our findings suggest that eurypalynous pollen grains define most Columneinae and that stenopalynous pollen grains define Chrysothemis ; however, comprehensive palynological studies involving a broader array of species within the subtribe are imperative to enhance our understanding of its palynology.
... In recent decades, recorded diversity in the subfamily has grown considerably as new taxa are being described continuously [e.g., 58,[64][65][66] especially in Vietnam [55][56][57][58][66][67][68][69][70][71]. However, molecular phylogenetic studies in the past decade also showed that traditional taxonomy of Gesneriaceae had utilized traits that are homoplasious [72][73][74][75][76]. Consequently, infrafamilial classification and generic delimitation of Gesneriaceae have undergone drastic changes in the past two decades [63,77]. ...
Situated in the southern end of the Annamite Mountain Range, Langbiang Plateau is a major biodiversity hotspot of southern Vietnam known for high species diversity and endemicity. To achieve effective conservation, parts of the plateau were designated as the Langbiang Biosphere Reserve, an UNESCO World Network aiming to improve relationships between inhabitants and their environments. Amongst the rich endemic flora of the plateau are three gesneriads ascribed to Primulina, a calciphilous genus with high species diversity in the vast limestone karsts stretching from southern China to northern Vietnam. However, a recent phylogenetic study questioned the generic placement of the Langbiang Primulina, corroborating with observations on the geographical distribution, habitat preference, and phyllotaxy of the three species. Based on phylogenetic analyses of nuclear ITS and plastid trnL-F DNA sequences of a comprehensive sampling covering nearly all genera of the Old World Gesneriaceae, we demonstrate that the three Langbiang Primulina species form a fully supported clade distantly related to other Primulina. As this clade is biogeographically, ecologically, morphologically, and phylogenetically distinct worthy of generic recognition, we propose to name it Langbiangia gen. nov. to highlight the rich and unique biodiversity of the Langbiang Plateau. By means of this taxonomic endeavor, we are hoping to raise the conservation awareness of this biodiversity heritage of southern Vietnam and promote the importance of Langbiang Biosphere Reserve that is crucial for achieving action-oriented global targets of the post-2020 global biodiversity framework (GBF) of the UN Convention on Biological Diversity (CBD)—effective conservation and management of at least 30% of biodiverse terrestrial, inland water, and costal and marine areas by 2030—that has been agreed at the COP15 in Montréal in December 2022.
... The Gesneriaceae family has colonized a great diversity of habitats and developed specialized plant-animal interactions that have led to a great diversity of floral morphologies as well ( Figure 1). These traits were first used for phylogenetic species classification, but because they highly converged in different Gesneriaceae lineages, the early taxonomy of the family was complex and contradictory [6][7][8]. ...
... The Gesneriaceae family has colonized a great diversity of habitats and developed specialized plant-animal interactions that have led to a great diversity of floral morphologies as well ( Figure 1). These traits were first used for phylogenetic species classification, but because they highly converged in different Gesneriaceae lineages, the early taxonomy of the family was complex and contradictory [6][7][8]. In recent years, the family has undergone a deep reconstruction due to advancements in molecular-phylogenetic studies, which concluded with a new basis for Gesneriaceae phylogeny in 2013 [1]. ...
Gesneriaceae is a pantropical family of plants that, thanks to their lithophytic and epiphytic growth forms, have developed different strategies for overcoming water scarcity. Desiccation tolerance or “resurrection” ability is one of them: a rare phenomenon among angiosperms that involves surviving with very little relative water content in their tissues until water is again available. Physiological responses of desiccation tolerance are also activated during freezing temperatures, a stress that many of the resurrection gesneriads suffer due to their mountainous habitat. Therefore, research on desiccation- and freezing-tolerant gesneriads is a great opportunity for crop improvement, and some of them have become reference resurrection angiosperms (Dorcoceras hygrometrica, Haberlea rhodopensis and Ramonda myconi). However, their difficult indoor cultivation and outdoor accessibility are major obstacles for their study. Therefore, this review aims to identify phylogenetic, geoclimatic, habitat, and morphological features in order to propose new tentative resurrection gesneriads as a way of making them more reachable to the scientific community. Additionally, shared and species-specific physiological responses to desiccation and freezing stress have been gathered as a stress response metabolic basis of the family.
... Most study species have fleshy fruits ( Table 1) that are presumably consumed by understory birds, as reported for M. rubescens (Kessler-Rios & Kattan, 2012) and closely related species (Loiselle & Blake, 1999), as well as for Psychotria, which is related to Palicourea and similar in habit and habitats (Loiselle et al., 1995;Loiselle & Blake, 1993;Theim et al., 2014). Drymonia have fleshy capsules, often termed "display-capsules" in understory Gesneriaceae, because of their presumed role in animal attraction (Clark et al., 2012). The limited reports suggest these are also consumed by understory birds, as well as frugivorous bats and monkeys (Wiehler, 1983). ...
... The capsular fruits of M. tomentosa probably have wind-or gravity-dispersed seeds, as in many understory Melastomataceae with the same type of fruit (Renner, 1989), potentially making this species the most limited in seed dispersal. All six species have mechanisms to reduce selfing, either via marked herkogamy (i.e., spatial separation of stigma and anthers via style elongation) in the Melastomataceae (Renner, 1989), protandry (i.e., temporal separation of male and female phases, with anthers releasing pollen and dying-off before stigma is receptive) in the Gesneriaceae (Clark et al., 2012;Wiehler, 1983), or distyly (i.e., polymorphism in style length within a population in which flowers in one individual are monomorphic) in the Rubiaceae (Bawa & Beach, 1983). Self-incompatibility (via intramorph incompatibility) is common in the Rubiaceae (Bawa & Beach, 1983), but less clear in the Gesneriaceae and Melastomataceae, where both selfincompatibility and self-compatibility have been documented (Ramírez-Aguirre et al., 2016;Renner, 1989). ...
Animal pollinators directly affect plant gene flow by transferring pollen grains between individuals. Pollinators with restricted mobility are predicted to limit gene flow within and among populations, whereas pollinators that fly longer distances are likely to promote genetic cohesion. These predictions, however, remain poorly tested. We examined population genetic structure and fine‐scale spatial genetic structure (FSGS) in six perennial understory angiosperms in Andean cloud forests of northwestern Ecuador. Species belong to three families (Gesneriaceae, Melastomataceae, and Rubiaceae), and within each family we paired one insect‐pollinated with one hummingbird‐pollinated species, predicting that insect‐pollinated species have greater population differentiation (as quantified with the FST statistic) and stronger FSGS (as quantified with the SP statistic) than hummingbird‐pollinated species. We confirmed putative pollinators through a literature review and fieldwork, and inferred population genetic parameters with a genome‐wide genotyping approach. In two of the three species pairs, insect‐pollinated species had much greater (>2‐fold) population‐level genetic differentiation and correspondingly steeper declines in fine‐scale genetic relatedness. In the Gesneriaceae pair, however, FST and SP values were similar between species and to those of the other hummingbird‐pollinated plants. In this pair, the insect pollinators are euglossine bees (as opposed to small bees and flies in the other pairs), which are thought to forage over large areas, and therefore may provide similar levels of gene flow as hummingbirds. Overall, our results shed light on how different animal pollination modes influence the spatial scale of plant gene flow, suggesting that small insects strongly decrease genetic cohesion.
... Columnea is strongly supported as a monophyletic genus based on molecular phylogenetic studies (Smith et al. 2013a;Schulte et al. 2014). Most subgeneric ranks are artificially defined and not supported by phylogenetic studies (Smith and Carroll 1997;Smith 2000;Clark and Zimmer 2003;Clark et al. 2012;Smith et al. 2013a;Schulte et al. 2014). Thus, we refrain from classifying the new species into a subgeneric rank. ...
Exploratory field expeditions to the Chocó forests in the northwestern slopes of the Ecuadorian and Colombian Andes resulted in the discovery of two new species of Columnea (Gesneriaceae). Columnea fluidifolia J.L.Clark & F.Tobar, sp. nov. , is described as a narrow endemic from Bosque Protector Mashpi and surrounding areas in the province of Pichincha in northern Ecuador. Columnea pendens F.Tobar, J.L.Clark & J.F.Sm., sp. nov. , is described from recently discovered populations in the provinces of Carchi and Santo Domingo de los Tsáchilas (Ecuador) and the departments of Cauca and Nariño in southwestern Colombia. The two new species are pendent epiphytes with elongate shoots and shallowly bilabiate to nearly tubular corollas. Descriptions, complete specimen citations, and a distribution map are provided. Based on IUCN guidelines, a preliminary conservation status of Critically Endangered (CR) is provided for C. fluidifolia and Endangered (EN) is provided for C. pendens .
... Coronantheroideae, Gesnerioideae and Didymocarpoideae (Wiehler 1983;Burtt and Wiehler 1995), which are considered monophyletic based on morphological, molecular data (ndhF sequences), chromosome number and secondary metabolites (Smith 1996;Smith et al. 1997); however, several studies have shown that groups within Gesneriaceae are not monophyletic (Smith 1996(Smith , 2000Smith et al. 1997;Citerne et al. 2000;Zimmer et al. 2002;Perret et al. 2003;Roalson et al. 2005aRoalson et al. , 2005bClark et al. 2006Clark et al. , 2012 which resulted in rearrangements in the taxonomic positioning of species, genera and tribes. Three subfamilies are currently accepted for Gesneriaceae: Sanangoideae, Gesnerioideae and Didymocarpoideae (Weber et al. 2013). ...
Napeantheae is a monogeneric tribe of Gesneriaceae (with Napeanthus Gardner), that presents species with different morphology from other Gesnerioideae, being herbs with rosulate leaves that
grow in pits, banks or at the base of rocks in humid forests. The tribe’s palynology is poorly known.
Thus, the aim of this study was to investigate the pollen morphology of the Brazilian native species of Napeanthus (Napeantheae) in order to expand the morphological knowledge of the tribe and
compare it with existing studies on Gesneriaceae. For the analysis, the pollen grains were removed from flower buds of exsiccatae deposited in herbaria; they were acetolyzed, measured, photographed
using light microscopy (LM) and scanning electron microscopy (SEM), and described qualitatively.
The analyzed species present differences in amb, polar area, shape, size of ectoapertures, type of endoapertures and exine thickness. The pollen grains are monads, isopolar, small, tricolporate, circulaperturate, ectoaperture rounded at the polar ends and without margo; the exine is semitectate, microreticulate-fossulate, sexine is thicker than nexine. An artificial pollen key is presented to help distinguish species. Quantitative pollen grain data confirm the qualitative differences
observed, especially in relation to the type of endoaperture. The microreticulate-fossulate exine ornamentation observed in Napeanthus has not previously been recorded for Gesneriaceae, especially in Gesnerioideae.
... The genus Glossoloma is defined by resupinate (upside down) flowers, a feature that was recently documented and discovered as a morphological synapomorphy (Clark and Zimmer 2003;Clark et al. 2006;Clark 2009;Clark et al. 2012). Glossoloma corollas are usually tubular, apically pouched and appear laterally compressed. ...
A new species of Glossoloma is described from the western Andean slopes of the Pichincha Province in northern Ecuador. Glossoloma wiehleri J.L.Clark & Tobar is differentiated from all other congeners by an epiphytic habit, elongate scandent shoots that exceed four meters in length, and coriaceous leaves with a velutinous indument on the lower leaf surface. The new species is illustrated, featured with field images from recent expeditions, and assigned the category of Endangered (EN) according to IUCN Criteria.
... or previously classified as members of the genus Dalbergaria Tussac. We refrain from classifying the new species to a subgeneric rank because most are artificially defined and not supported by phylogenetic studies (Smith and Carroll 1997;Smith 2000;Clark and Zimmer 2003;Clark et al. 2012;Smith et al. 2013;Schulte et al. 2014). The three species described here are distributed on the western Andean slopes of northern Ecuador and southern Colombia (Fig. 1). ...
Three new species of Columnea (Gesneriaceae, tribe Gesnerieae) are described from the western Andean slopes of northern Ecuador and southern Colombia. Columnea angulata J.L. Clark & F. Tobar and Columnea floribunda F. Tobar & J.L. Clark are described from northern Ecuador. Columnea tecta J.L. Clark & Clavijo is described from southern Colombia and northern Ecuador. The three new species are facultative epiphytes with dorsiventral shoots and are readily recognized by bright red tips on the abaxial and adaxial leaf surfaces. The species described here are vegetatively similar to the sympatric species Columnea picta H. Karst. and are readily differentiated by floral features that are illustrated, described and featured with digital images.
... A phylogenetic tree (Figure 1) was constructed with the maximum likelihood (ML) method and the TVM þ F þ R2 evolutionary model using RAxML (Stamatakis 2014). The result was congruent with previous studies that established that Achimenes is a member of the New World Gesneriaceae (Clark et al. 2012;Weber et al. 2013). The topology of this molecular tree supports the division of this subfamily and shows that A. cettoana is a representative of Subtr. ...
... The topology of this molecular tree supports the division of this subfamily and shows that A. cettoana is a representative of Subtr. Gloxiniinae and is a sister group of Gesneriinae (Clark et al. 2012). The newly reported chloroplast genome of A. cettoana allows developing markers for further studies on resolving the relationship within the Subfam. ...
Achimenes Pers. is well known for its floral diversity and widely used in horticulture, but its phylogenetic position is still poorly understood. And most research about the complete chloroplast genome sequence focused on the Old World species; therefore, we think it is necessary to examine taxa of the New World in more detail. This study determined the complete chloroplast genome of Achimenes cettoana H.E. Moore. The cp genome was 153,011 bp in a total length containing two inverted repeats (IRs) of 25,162 bp separated by a large single-copy (LSC) region of 84,669 bp and a small single-copy (SSC) region of 18,018 bp. The whole cp genome of A. cettoana contains 112 genes, including 79 protein-coding genes, 29 tRNA genes, and four rRNA genes. This plastid genome is firstly reported in the New World Gesneriaceae, which will be a valuable resource for future studies on breeding, conservation genetics, and phylogeny of Gesneriaceae.
... The colonization of a wide range of habitats and the evolution of specialized plant-animal interactions to achieve pollination and seed dispersal has strongly influenced the diversification of this clade since its origin around 70 million years ago (Roalson and Roberts, 2016;Serrano-Serrano et al., 2017). The extensive diversity of Gesneriaceae in habit and floral morphology coupled with high levels of convergence in these traits caused considerable confusion in the early taxonomy of this family (Jong and Burtt, 1975;Clark et al., 2012). To date, phylogenetic inference in this plant group has mainly relied on plastid markers (e.g., atpB-rbcL, psbA-trnH, trnL-trnF, ndhF) and few multi-copy nuclear ribosomal regions such as ITS, and to a lower extent, low-copy nuclear genes such as GLUTAMINE SYNTHETASE (ncpGS) and CYCLOEDIA (CYC) (reviewed in Möller and Clark, 2013;Roalson and Roberts, 2016). ...
... To date, phylogenetic inference in this plant group has mainly relied on plastid markers (e.g., atpB-rbcL, psbA-trnH, trnL-trnF, ndhF) and few multi-copy nuclear ribosomal regions such as ITS, and to a lower extent, low-copy nuclear genes such as GLUTAMINE SYNTHETASE (ncpGS) and CYCLOEDIA (CYC) (reviewed in Möller and Clark, 2013;Roalson and Roberts, 2016). Phylogenetic hypotheses derived from these genetic markers provided the framework to redefine the generic and tribal boundaries and to develop a new formal classification of the family (Zimmer et al., 2002;Perret et al., 2003;Roalson et al., 2005;Clark et al., 2006;Möller et al., 2009Möller et al., , 2011Clark et al., 2012;Weber et al., 2013). The analyses of these sequence data using supermatrix approaches also provided large scale phylogenetic hypotheses for the entire family (768 species; Roalson and Roberts, 2016) and the Gesnerioideae subfamily (583 species; Serrano-Serrano et al., 2017). ...
Gesneriaceae (ca. 3400 species) is a pantropical plant family with a wide range of growth form and floral morphology that are associated with repeated adaptations to different environments and pollinators. Although Gesneriaceae systematics has been largely improved by the use of Sanger sequencing data, our understanding of the evolutionary history of the group is still far from complete due to the limited number of informative characters provided by this type of data. To overcome this limitation, we developed here a Gesneriaceae-specific gene capture kit targeting 830 single-copy loci (776,754 bp in total), including 279 genes from the Universal Angiosperms-353 kit. With an average of 557,600 reads and 87.8% gene recovery, our target capture was successful across the family Gesneriaceae and also in other families of Lamiales. From our bait set, we selected the most informative 418 loci to resolve phylogenetic relationships across the entire Gesneriaceae family using maximum likelihood and coalescent-based methods. Upon testing the phylogenetic performance of our baits on 78 taxa representing 20 out of 24 subtribes within the family, we showed that our data provided high support for the phylogenetic relationships among the major lineages, and were able to provide high resolution within more recent radiations. Overall, the molecular resources we developed here open new perspectives for the study of Gesneriaceae phylogeny at different taxonomical levels and the identification of the factors underlying the diversification of this plant group.