The Sequential Direct and Indirect Effects of Mountain Uplift, Climatic Niche, and Floral Trait Evolution on Diversification Dynamics in an Andean Plant Clade.

Why and how organismal lineages radiate is commonly studied through either assessing abiotic factors (biogeography, geomorphological processes, and climate) or biotic factors (traits and interactions). Despite increasing awareness that both abiotic and biotic processes may have important joint effects on diversification dynamics, few attempts have been made to quantify the relative importance and timing of these factors, and their potentially interlinked direct and indirect effects, on lineage diversification. We here combine assessments of historical biogeography, geomorphology, climatic niche, vegetative, and floral trait evolution to test whether these factors jointly, or in isolation, explain diversification dynamics of a Neotropical plant clade (Merianieae, Melastomataceae). After estimating ancestral areas and the changes in niche and trait disparity over time, we employ Phylogenetic Path Analyses as a synthesis tool to test eleven hypotheses on the individual direct and indirect effects of these factors on diversification rates. We find strongest support for interlinked effects of colonization of the uplifting Andes during the mid-Miocene and rapid abiotic climatic niche evolution in explaining a burst in diversification rate in Merianieae. Within Andean habitats, later increases in floral disparity allowed for the exploitation of wider pollination niches (i.e., shifts from bee to vertebrate pollinators), but did not affect diversification rates. Our approach of including both vegetative and floral trait evolution, rare in assessments of plant diversification in general, highlights that the evolution of woody habit and larger flowers preceded the colonization of the Andes, but was likely critical in enabling the rapid radiation in montane environments. Overall, and in concert with the idea that ecological opportunity is a key element of evolutionary radiations, our results suggest that a combination of rapid niche evolution and trait shifts was critical for the exploitation of newly available niche space in the Andes in the mid-Miocene. Further, our results emphasize the importance of incorporating both abiotic and biotic factors into the same analytical framework if we aim to quantify the relative and interlinked effects of these processes on diversification.

Acoustic traits of bat-pollinated flowers compared to flowers of other pollination syndromes and their echo-based classification using convolutional neural networks.

Bat-pollinated flowers have to attract their pollinators in absence of light and therefore some species developed specialized echoic floral parts. These parts are usually concave shaped and act like acoustic retroreflectors making the flowers acoustically conspicuous to the bats. Acoustic plant specializations only have been described for two bat-pollinated species in the Neotropics and one other bat-dependent plant in South East Asia. However, it remains unclear whether other bat-pollinated plant species also show acoustic adaptations. Moreover, acoustic traits have never been compared between bat-pollinated flowers and flowers belonging to other pollination syndromes. To investigate acoustic traits of bat-pollinated flowers we recorded a dataset of 32320 flower echoes, collected from 168 individual flowers belonging to 12 different species. 6 of these species were pollinated by bats and 6 species were pollinated by insects or hummingbirds. We analyzed the spectral target strength of the flowers and trained a convolutional neural network (CNN) on the spectrograms of the flower echoes. We found that bat-pollinated flowers have a significantly higher echo target strength, independent of their size, and differ in their morphology, specifically in the lower variance of their morphological features. We found that a good classification accuracy by our CNN (up to 84%) can be achieved with only one echo/spectrogram to classify the 12 different plant species, both bat-pollinated and otherwise, with bat-pollinated flowers being easier to classify. The higher classification performance of bat-pollinated flowers can be explained by the lower variance of their morphology.

Effects of heterospecific pollen on stigma behavior in Campsis radicans: Causes and consequences.

PREMISE: Pollinator sharing of co-flowering plants may result in interspecific pollen receipt with a fitness cost. However, the underlying factors that determine the effects of heterospecific pollen (HP) are not fully understood. Moreover, the cost of stigma closure induced by HP may be more severe for plants with special touch-sensitive stigmas than for plants with non-touch-sensitive stigmas. Very few studies have assessed HP effects on stigma behavior. METHODS: We conducted hand-pollination experiments with 10 HP donors to estimate HP effects on stigma behavior and stigmatic pollen germination in Campsis radicans (Bignoniaceae) at low and high pollen loads. We assessed the role of phylogenetic distance between donor and recipient, pollen size, and pollen aperture number in mediating HP effects. Additionally, we observed pollen tube growth to determine the conspecific pollen-tube-growth advantage. RESULTS: Stigma behavior differed significantly with HP of different species. Pollen load increased, while pollen size decreased, the percentage of permanent closure and stigmatic germination of HP. Stigmatic HP germination increased with increasing aperture number. However, HP effects did not depend on phylogenetic distance. In addition, conspecific pollen had a pollen-tube-growth advantage over HP. CONCLUSIONS: Our results provide a good basis for understanding the stigma-pollen recognition process of plant taxa with touch-sensitive stigmas. We concluded that certain flowering traits drive the HP effects on the post-pollination period. To better understand the impact of pollinator sharing and interspecific pollen transfer on plant evolution, we highlight the importance of evaluating more factors that determine HP effects at the community level.

Historical nectar assessment reveals the fall and rise of floral resources in Britain.

There is considerable concern over declines in insect pollinator communities and potential impacts on the pollination of crops and wildflowers. Among the multiple pressures facing pollinators, decreasing floral resources due to habitat loss and degradation has been suggested as a key contributing factor. However, a lack of quantitative data has hampered testing for historical changes in floral resources. Here we show that overall floral rewards can be estimated at a national scale by combining vegetation surveys and direct nectar measurements. We find evidence for substantial losses in nectar resources in England and Wales between the 1930s and 1970s; however, total nectar provision in Great Britain as a whole had stabilized by 1978, and increased from 1998 to 2007. These findings concur with trends in pollinator diversity, which declined in the mid-twentieth century but stabilized more recently. The diversity of nectar sources declined from 1978 to 1990 and thereafter in some habitats, with four plant species accounting for over 50% of national nectar provision in 2007. Calcareous grassland, broadleaved woodland and neutral grassland are the habitats that produce the greatest amount of nectar per unit area from the most diverse sources, whereas arable land is the poorest with respect to amount of nectar per unit area and diversity of nectar sources. Although agri-environment schemes add resources to arable landscapes, their national contribution is low. Owing to their large area, improved grasslands could add substantially to national nectar provision if they were managed to increase floral resource provision. This national-scale assessment of floral resource provision affords new insights into the links between plant and pollinator declines, and offers considerable opportunities for conservation.

A chemometric approach for the differentiation of 15 monofloral honeys based on physicochemical parameters.

BACKGROUND: Although the main method for authentication of monofloral honey is pollen analysis, other classification approaches have been also applied. However, the majority of the existing classification models so far have utilized a few honey types or a few honey samples of each honey type, which can lead to inaccurate results. Aiming at addressing this, the goal of the present study was to create a classification model by analysing in total 250 honey samples from 15 different monofloral honey types in ten physicochemical parameters and then, multivariate analysis [multivariate analysis of variance (MANOVA), principal component analysis (PCA) and multi-discriminant analysis (MDA)] was applied in an effort to distinguish and classify them. RESULTS: Electrical conductivity and colour were found to have the highest discriminative power, allowing the classification of monofloral honey types, such as oak, knotgrass and chestnut honey, as well as the differentiation between honeydew and nectar honeys. The classification model had a high predictive power, as the 84.4% of the group cases was correctly classified, while for the cases of chestnut, strawberry tree and sunflower honeys the respective prediction was correct by 91.3%, 95% and 100%, allowing further determination of unknown honey samples. CONCLUSION: It seems that the characterization of monofloral honeys based on their physicochemical parameters through the proposed model can be achieved and further applied on other honey types. The results could contribute to the development of methodologies for the determination of honey's botanical origin, based on simple techniques, so that these can be applied for routine analysis. © 2021 Society of Chemical Industry.

Combination of Sanger and target-enrichment markers supports revised generic delimitation in the problematic 'Urera clade' of the nettle family (Urticaceae).

Urera Gaudich, s.l. is a pantropical genus comprising c. 35 species of trees, shrubs, and vines. It has a long history of taxonomic uncertainty, and is repeatedly recovered as polyphyletic within a poorly resolved complex of genera in the Urticeae tribe of the nettle family (Urticaceae). To provide generic delimitations concordant with evolutionary history, we use increased taxonomic and genomic sampling to investigate phylogenetic relationships among Urera and associated genera. A cost-effective two-tier genome-sampling approach provides good phylogenetic resolution by using (i) a taxon-dense sample of Sanger sequence data from two barcoding regions to recover clades of putative generic rank, and (ii) a genome-dense sample of target-enrichment data for a subset of representative species from each well-supported clade to resolve relationships among them. The results confirm the polyphyly of Urera s.l. with respect to the morphologically distinct genera Obetia, Poikilospermum and Touchardia. Afrotropic members of Urera s.l. are recovered in a clade sister to the xerophytic African shrubs Obetia; and Hawaiian ones with Touchardia, also from Hawaii. Combined with distinctive morphological differences between Neotropical and African members of Urera s.l., these results lead us to resurrect the previously synonymised name Scepocarpus Wedd. for the latter. The new species epiphet Touchardia oahuensis T.Wells & A.K. Monro is offered as a replacement name for Touchardia glabra non H.St.John, and subgenera are created within Urera s.s. to account for the two morphologically distinct Neotropical clades. This new classification minimises taxonomic and nomenclatural disruption, while more accurately reflecting evolutionary relationships within the group.

An attempt to classify the botanical origin of honey using visible spectroscopy.

BACKGROUND: The production of honey, and especially the unifloral varieties, is limited by factors such as weather conditions or the availability of nectar flow and honeydew. This results in a deficit in supply leading to the adulteration of honey. If they are not properly labeled, customers cannot distinguish artificial / synthetic products from real honey. Currently, the basic, commonly used method for determining the varieties of honey (botanical origin) is palynological analysis. However, this procedure is quite difficult owing to the dearth of experienced staff in the field of melissopalynology. RESULTS: A method for identifying and classifying natural honey accurately based on its botanical origin has therefore been proposed. This analysis would rely on the visible light spectra transmitted through a relatively thin layer of the substance of interest, regardless of deviations in thickness. We present algorithms for analyzing the transmittance spectra-parametrization based on polynomial approximation (PMA) and applying a method for spectra selection and reduction (SSR) and a classical classification model (decision tree). A comparison is presented of the classification of four varieties of honey, confirmed by pollen analysis, obtained from the analysis of optically measured transmittance spectra of the samples. The algorithms that are compared contain a decision tree that uses raw data, data reduced by principal component analysis (PCA), and data after calculations based on the proposed algorithms alone (PMA and SSR) and together with the PCA method. CONCLUSION: This novel method produced outstanding results in comparison with the standard PCA method and is helpful in identifying the botanical origin of honey effectively. © 2021 Society of Chemical Industry.

Botanical origin discrimination of Greek honeys: physicochemical parameters versus Raman spectroscopy.

BACKGROUND: The authenticity of honey is of high importance since it affects its commercial value. The discrimination of the origin of honey is of prime importance to reinforce consumer trust. In this study, four chemometric models were developed based on the physicochemical parameters according to European and Greek legislation and one using Raman spectroscopy to discriminate Greek honey samples from three commercial monofloral botanical sources. RESULTS: The results of physicochemical (glucose, fructose, electrical activity) parameters chemometric models showed that the percentage of correct recognition fluctuated from 92.2% to 93.8% with cross-validation 90.6-92.2%, and the placement of test set was 79.0-84.3% successful. The addition of maltose content in the previous discrimination models did not significantly improve the discrimination. The corresponding percentages of the Raman chemometric model were 95.3%, 90.6%, and 84.3%. CONCLUSION: The five chemometric models developed presented similar and very satisfactory results. Given that the recording of Raman spectra is simple, fast, a minimal amount of sample is needed for the analysis, no solvent (environmentally friendly) is used, and no specialized personnel are required, we conclude that the chemometric model based on Raman spectroscopy is an efficient tool to discriminate the botanical origin of fir, pine, and thyme honey varieties. © 2020 Society of Chemical Industry.

Investigation of genes associated with petal variations between diploid and autotetraploid in Chinese cabbage (Brassica rapa L. ssp. pekinensis) by RNA-seq and sRNA-seq.

Polyploidy promotes morphological, physiological, and reproductive diversity in plants. The imminent effect of chromosome doubling in plants is the enlargement of organs such as flowers and fruits, which increases the commercial value of crops. Flowering plays a vital role in the growth and development of angiosperms. Here, we prepared an isolated microspore culture of 'FT', a doubled haploid (DH) line of Chinese cabbage (Brassica rapa L. ssp. pekinensis), and obtained diploid and autotetraploid plants with the same genetic background. Compared with diploids, the autotetraploids were characterized by large floral organs, dark petals, delayed flowering, and reduced fertility. The indole-3-acetic acid (IAA) and jasmonic acid (JA) levels in autotetraploid petals were significantly higher and the abscisic acid (ABA) level was significantly lower than those in the diploid petals. The lutein level in autotetraploid petals was nearly two times higher than that in the diploid petals. A comparative transcriptome analysis revealed 14,412 differentially expressed genes (DEGs) between the diploids and autotetraploids, and they were enriched in 117 Gene Ontology terms and 110 Kyoto Encyclopedia of Genes and Genomes pathways. We detected 231 DEGs related to phytohormone signal transduction and 29 DEGs involved in carotenoid biosynthesis. An miRNA-target mRNA analysis showed that 32 DEGs regulated by 16 DEMs were associated with flowering timing (BraA03000336, BraA09004319, and BraA09000515), petal development (BraA05002408, BraA01004006, BraA09004069, and BraA04000966), flower opening (BraA07000350), and pollen development (BraA01000720, BraA09005727, and BraA01000253). This study provides information to help elucidate the molecular mechanisms underlying phenotypic variations induced by autopolyploidy in Chinese cabbage.

Molecular phylogenetics and floral evolution of the Cirrhopetalum alliance (Bulbophyllum, Orchidaceae): Evolutionary transitions and phylogenetic signal variation.

The Cirrhopetalum alliance is a loosely circumscribed species-rich group within the mega-diverse genus Bulbophyllum (Orchidaceae). The monophyletic status of the alliance has been challenged by previous studies, although established sectional classifications have yet to be tested in a phylogenetic context. We used maximum likelihood and Bayesian analyses of DNA sequence data (cpDNA: matK and psbA-trnH; nrDNA: ITS and Xdh; 3509 aligned characters; 117 taxa), including all sections putatively associated with the Cirrhopetalum alliance, to reconstruct the phylogeny. We mapped 11 selected categorical floral characters onto the phylogeny to identify synapomorphies and assess potential evolutionary transitions across major clades. Our results unequivocally support the recognition of an amended Cirrhopetalum alliance as a well-supported monophyletic group characterized by clear synapomorphies, following the inclusion of sect. Desmosanthes and the exclusion of five putative Cirrhopetalum-allied sections. Most sections within the Cirrhopetalum alliance are demonstrated to be polyphyletic or paraphyletic, necessitating a new sectional classification. The inclusion of sect. Desmosanthes revolutionizes our understanding of the alliance, with significant evolutionary transitions in floral characters detected. We further investigated six continuously variable characters of the sepals and labellum, and detect phylogenetic conservatism in labellum width and the evolutionary lability of lateral sepal length, which can partly be explained by the different functional roles they play in pollination and pollinator trapping.

Cloning and Functional Characterization of Dihydroflavonol 4-Reductase Gene Involved in Anthocyanin Biosynthesis of Chrysanthemum.

Dihydroflavonol 4-reductase (DFR) catalyzes a committed step in anthocyanin and proanthocyanidin biosynthesis by reducing dihydroflavonols to leucoanthocyanidins. However, the role of this enzyme in determining flower color in the economically important crop chrysanthemum (Chrysanthemum morifolium Ramat.) is unknown. Here, we isolated cDNAs encoding DFR from two chrysanthemum cultivars, the white-flowered chrysanthemum "OhBlang" (CmDFR-OB) and the red-flowered chrysanthemum "RedMarble" (CmDFR-RM) and identified variations in the C-terminus between the two sequences. An enzyme assay using recombinant proteins revealed that both enzymes catalyzed the reduction of dihydroflavonol substrates, but CmDFR-OB showed significantly reduced DFR activity for dihydrokaempferol (DHK) substrate as compared with CmDFR-RM. Transcript levels of anthocyanin biosynthetic genes were consistent with the anthocyanin contents at different flower developmental stages of both cultivars. The inplanta complementation assay, using Arabidopsis thaliana dfr mutant (tt3-1), revealed that CmDFR-RM, but not CmDFR-OB, transgenes restored defective anthocyanin biosynthesis of this mutant at the seedling stage, as well as proanthocyanidin biosynthesis in the seed. The difference in the flower color of two chrysanthemums can be explained by the C-terminal variation of CmDFR combined with the loss of CmF3H expression during flower development.

Comprehensive analysis of bZIP transcription factors uncovers their roles during dimorphic floret differentiation and stress response in Cleistogenes songorica.

BACKGROUND: Transcription factors act as important regulators of transcription networks. Basic leucine zipper (bZIP) transcription factors have been shown to be involved in multiple biological processes in plants. However, no information is available for the bZIP family in Cleistogenes songorica, which is an important xerophytic and allotetraploid grass in desert grasslands. RESULTS: In this study, 86 CsbZIPs were identified in the allotetraploid C. songorica genome. For location analysis, CsbZIPs were distributed evenly across two subgenomes of C. songorica. Phylogenetic tree analysis among three species indicated that CsbZIPs were evolutionarily more closely related to OsbZIPs than AtbZIPs. Syntenic and phylogenetic analyses confirmed that the CsbZIPs were mainly expanded by whole-genome duplication events. Furthermore, it was determined that rice and C. songorica might have undergone purified selection during their long evolutionary history by calculating the Ks values and Ka/Ks ratios of orthologous gene pairs. By analysing the expression patterns of CsbZIPs in different tissues and under abiotic stresses, 21 CsbZIP genes were differentially expressed between chasmogamous (CH) and cleistogamous (CL) flowers, including two FLOWERING LOCUS D (FD) genes. In shoots and roots, 79.1 and 87.2% of the CsbZIP genes, respectively, displayed transcript changes under at least one stress treatment, such as heat, cold, drought and salt. Strikingly, 17 common CsbZIP genes showed differential expression under stress response and during CL flowering. Co-expression network, GO annotation and real-time quantitative reverse transcription PCR (qRT-PCR) analyses revealed a close relationship between CL flowering-associated genes and abiotic stress-related genes. CONCLUSIONS: BZIP TFs were comprehensively analysed and identified in allotetraploid C. songorica. Our results provide insights into the evolutionary history of the bZIP family in C. songorica and provide abiotic stress-responsive and CL-associated candidate CsbZIP genes for potential applications in the genetic improvement of plants.

Automated plant species identification-Trends and future directions.

Current rates of species loss triggered numerous attempts to protect and conserve biodiversity. Species conservation, however, requires species identification skills, a competence obtained through intensive training and experience. Field researchers, land managers, educators, civil servants, and the interested public would greatly benefit from accessible, up-to-date tools automating the process of species identification. Currently, relevant technologies, such as digital cameras, mobile devices, and remote access to databases, are ubiquitously available, accompanied by significant advances in image processing and pattern recognition. The idea of automated species identification is approaching reality. We review the technical status quo on computer vision approaches for plant species identification, highlight the main research challenges to overcome in providing applicable tools, and conclude with a discussion of open and future research thrusts.

DNA barcoding detects floral origin of Indian honey samples.

The unique medicinal and nutritional properties of honey are determined by its chemical composition. To evaluate the quality of honey, it is essential to study the surrounding vegetation where honeybees forage. In this study we used conventional melissopalynological and DNA barcoding techniques to determine the floral source of honey samples collected from different districts of the state of Mizoram, India. Pollen grains were isolated and genomic DNA was extracted from the honey samples. PCR amplification was carried out using universal barcode candidates ITS2 and rbcL to identify the plant species. Furthermore, TA cloning was carried out to screen the PCR amplicon libraries to identify the presence of multiple plant species. Results from both the melissopalynological and DNA barcoding analyses identified almost exactly the same 22 species, suggesting that both methods are suitable for analysis. However, DNA barcoding is easier and widely practiced. Hence, it can be concluded that DNA barcoding is a useful tool in determining the medicinal and commercial value of honey.

Wild Bee Pollen Usage and Microbial Communities Co-vary Across Landscapes.

Bees forage for pollen and nectar at flowers but simultaneously acquire pathogenic, commensal, and likely beneficial microbes from these same flowers. Characterizing pollen usage of wild bees is therefore crucial to their conservation yet remains a challenging task. To understand pollen usage across landscapes and how this affects microbial communities found in the pollen provisions collected from flowers, we studied the generalist small carpenter bee Ceratina australensis. We collected C. australensis nests from three different climatic zones across eastern and southern Australia. To characterize the plant, fungal, and bacterial composition of these pollen provisions, we used a metabarcoding and next-generation sequencing approach. We found that the species richness of plant types, fungi, and bacteria was highest in a subtropical zone compared to a temperate or a grassland zone. The composition of these communities also differentiated by zone, particularly in pollen composition and fungal communities. Moreover, pollen composition strongly correlated with fungal community composition, suggesting that variation in pollen usage across landscapes results in variation in microbial communities. While how these pollen usage and microbial community patterns affect bee health merits additional work, these data further our understanding of how flowering plant community composition affects not only the pollen usage of a generalist bee but also its associated microbial communities.

New Caffeoylquinic Acid Derivatives and Flavanone Glycoside from the Flowers of Chrysanthemum morifolium and Their Bioactivities.

The Chrysanthemum morifolium flower is widely used in China and Japan as a food, beverage, and medicine for many diseases. In our work, two new caffeoylquinic acid derivatives (1, 2), a new flavanone glycoside (3), and six reported flavanones (4⁻9) were isolated and identified from the flowers of C. morifolium. The chemical structures of all isolates were elucidated by the analysis of comprehensive spectroscopic data as well as by comparison with previously reported data. The isolated constituents 1⁻8 were evaluated for their neuroprotective activity, and compounds 3 and 4 displayed neuroprotective effects against hydrogen peroxide-induced neurotoxicity in human neuroblastoma SH-SY5Y cells.

Identification of Floral Scent Profiles in Bearded Irises.

Bearded irises are ornamental plants with distinctive floral fragrance grown worldwide. To identify the floral scent profiles, twenty-seven accessions derived from three bearded iris, including Iris. germanica, I. pumila and I. pallida were used to investigate the composition and relative contents of floral scent components by headspace solid-phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS). A total of 219 floral scent components were detected in blooming flowers. The scent profile varied significantly among and within the three investigated species. Principal component analysis (PCA) indicated that terpenes, alcohols and esters contributed the most to the floral scent components and 1-caryophyllene, linalool, citronellol, methyl cinnamate, ß-cedrene, thujopsene, methyl myristate, linalyl acetate, isosafrole, nerol, geraniol were identified as the major components. In a hierarchical cluster analysis, twenty-seven accessions could be clustered into six different groups, most of which had representative scent components such as linalool, citronellyl acetate, thujopsene, citronellol, methyl cinnamate and 1-caryophyllene. Our findings provide a theoretical reference for floral scent evaluation and breeding of bearded irises.

Drought reduces floral resources for pollinators.

Climate change is predicted to result in increased occurrence and intensity of drought in many regions worldwide. By increasing plant physiological stress, drought is likely to affect the floral resources (flowers, nectar and pollen) that are available to pollinators. However, little is known about impacts of drought at the community level, nor whether plant community functional composition influences these impacts. To address these knowledge gaps, we investigated the impacts of drought on floral resources in calcareous grassland. Drought was simulated using rain shelters and the impacts were explored at multiple scales and on four different experimental plant communities varying in functional trait composition. First, we investigated the effects of drought on nectar production of three common wildflower species (Lathyrus pratensis, Onobrychis viciifolia and Prunella vulgaris). In the drought treatment, L. pratensis and P. vulgaris had a lower proportion of flowers containing nectar and O. viciifolia had fewer flowers per raceme. Second, we measured the effects of drought on the diversity and abundance of floral resources across plant communities. Drought reduced the abundance of floral units for all plant communities, irrespective of functional composition, and reduced floral species richness for two of the communities. Functional diversity did not confer greater resistance to drought in terms of maintaining floral resources, probably because the effects of drought were ubiquitous across component plant communities. The findings indicate that drought has a substantial impact on the availability of floral resources in calcareous grassland, which will have consequences for pollinator behaviour and populations.

The monotypic Brazilian genus Diacrodon is a synonym of Borreria (Spermacoceae, Rubiaceae): morphological and molecular evidences.

Diacrodon is a monotypic genus of the tribe Spermacoceae (Rubiaceae), endemic to northeastern Brazil. Diacrodon compressus is frequently misidentified with a two lobed calyx species of Borreria, B. verticillata. Traditionally, in Spermacoceae the fruit type was considered a diagnostic character among the genera. In this sense, D. compressus presents a strongly compressed, one seeded and indehiscent fruit (vs. globose, two seeded and dehiscent fruit in B. verticillata). In this work, we address two objectives: evaluate the systematic position and determine the identity of Diacrodon in respect to other taxa. Molecular analyses using ITS and ETS indicate that D. compressus is strongly related to other species of Borreria. The morphological results revealed that D. compressus, despite of its type of fruit, is identical to Borreria in floral and palynological features. As conclusion, the new combination Borreria diacrodonta is made and a lectotype is designated. An updated description of the species and a key to the Borreria species with a two lobed calyx are provided. The distribution of B. diacrodonta is extended to Brazilian states Goiás and Minas Gerais, and Paraguay. By this taxonomical change it has become clear that the dehiscence of the fruits lack taxonomic value in the delimitation of Borreria.