Molecular phylogenetics of Melastomataceae and Memecylaceae: implications for character evolution

Diversity of staminal nectariferous appendages in disymmetric and zygomorphic flowers of Fumarioideae (Papaveraceae)

Staminal nectaries show diversity in their position, size, shape, color, and number in Ranunculales. In Papaveraceae, nectaries only appear at the base of stamen in these lineages with disymmetric and zygomorphic flowers. However, the diversity of the staminal nectaries' developmental characteristics and structure is unknown. The diversity of staminal nectaries of Hypecoum erectum, Ichtyoselmis macrantha, Adlumia asiatica, Dactylicapnos torulosa, Corydalis edulis, and Fumaria officinalis (six species belonging to six genera, respectively) in the Fumarioideae was investigated under scanning electron microscopy, light microscopy, and transmission electron microscopy. In all species studied, according to the developmental characteristics of the nectaries, four developmental stages can be divided into initiation, enlargement, differentiation, and maturation, and the number of nectaries can be determined at the stage of initiation (stage 1), and morphological differentiation occurs at the developmental stage 3. The staminal nectaries consist of secretory epidermis, parenchyma tissue, and phloem with some sieve tube elements reaching the secretory parenchyma cells; however, the number of cell layers of parenchyma can vary from 30 to 40 in I. macrantha and D. torulosa, to only 5 to 10 like in F. officinalis. Secretory epidermis cells are larger than secretory parenchyma cells with abundant microchannels on the outer cell wall. There were abundant mitochondria, Golgi bodies, rough endoplasmic reticulum, and plastids in secretory parenchyma cells. Nectar is stored in the intercellular space and exuded to the exterior via microchannels. In A. asiatica, according to the evidence of small secretory cell characteristics such as dense cytoplasm, and numerous mitochondria, together with the filamentous secretions present on the surface of epidermal cells on groove, it can be inferred that the U-shaped sulcate which is located in the white projection formed at the filament of triplets in A. asiatica is nectariferous.

Connective modifications and origin of stamen diversity in Melastomataceae

The androecium of Melastomataceae presents notable modifications in its merosity, morphology between whorls and in prolonged connectives and appendages. We carried out a comparative study of six Melastomataceae species to shed light on the developmental processes that originate such stamen diversity. The development of stamens was studied using scanning electron microscopy and histological observations. The stamens of all species studied have a curved shape because they emerge on a plane displaced by the perigynous hypanthium. They are the last flower organs to initiate and therefore their growth is inwards and towards the floral center. Despite the temporal inversion between carpels and stamens in Melastomataceae, the androecium maintains the centripetal pattern of development, the antepetalous stamens emerging after antesepalous stamens. The isomerous androecium can be the result of abortion of the antepetalous stamens, whereas heterostemony seems to be caused by differences in position and the stamen development time. Pedoconnectives and ventral appendages originate from the basal expansion of the anther late in floral development. The delay in stamen development may be a consequence of their dependence on the formation of a previous space so that they can grow. Most of the stamen diversity is explained by the formation of the connectives and their appendages. The formation of a basal-ventral anther prolongation, which culminates in the development of the pedoconnective, does not differ from other types of sectorial growth of the connective, which form shorter structures.

Out of chaos: Phylogenomics of Asian Sonerileae

Sonerileae is a diverse Melastomataceae lineage comprising ca. 1000 species in 44 genera, with >70% of genera and species distributed in Asia. Asian Sonerileae are taxonomically intractable with obscure generic circumscriptions. The backbone phylogeny of this group remains poorly resolved, possibly due to complexity caused by rapid species radiation in early and middle Miocene, which hampers further systematic study. Here, we used genome resequencing data to reconstruct the phylogeny of Asian Sonerileae. Three parallel datasets, viz. single-copy ortholog (SCO), genomic SNPs, and whole plastome, were assembled from genome resequencing data of 205 species for this purpose. Based on these genome-scale data, we provided the first well resolved phylogeny of Asian Sonerileae, with 34 major clades identified and 74% of the interclade relationships consistently resolved by both SCO and genomic data. Meanwhile, widespread phylogenetic discordance was detected among SCO gene trees as well as species trees reconstructed using different tree estimation methods (concatenation/site-based coalescent method/summary method) or different datasets (SCO/genomic/plastome). We explored sources of discordance using multiple approaches and found that the observed discordance in Asian Sonerileae was mainly caused by a combination of biased distribution of missing data, random noise from uninformative genes, incomplete lineage sorting, and hybridization/introgression. Exploration of these sources can enable us to generate hypotheses for future testing, which is the first step towards understanding the evolution of Asian Sonerileae. We also detected high levels of homoplasy for some characters traditionally used in taxonomy, which explains current chaotic generic delimitations. The backbone phylogeny of Asian Sonerileae revealed in this study offers a solid basis for future taxonomic revision at the generic level.

Flavanone Glycosides, Triterpenes, Volatile Compounds and Antimicrobial Activity of Miconia minutiflora (Bonpl.) DC. (Melastomataceae)

Chemical composition of the essential oils and extracts and the antimicrobial activity of Miconia minutiflora were investigated. The flavanone glycosides, pinocembroside and pinocembrin-7-O-[4″,6″-HHDP]-β-D-glucose, were identified, along with other compounds that belong mainly to the triterpene class, besides the phenolics, gallic acid and methyl gallate. Sesquiterpenes and monoterpenes were the major compounds identified from the essential oils. Screening for antimicrobial activity from the methanolic extract of the leaves showed that the MIC and MMC values against the tested microorganisms ranged from 0.625 to 5 mg·mL−1 and that the extract was active against microorganisms, Staphyloccocus aureus, Escherichia coli, and Bacillus cereus.

Melastomataceae in Parque Estadual Paulo César Vinha, Guarapari, Espírito Santo, Brazil

Abstract Melastomataceae are the tenth most diverse angiosperm family in the world and the sixth largest angiosperm family in Brazil. Among the ecosystems associated with the Atlantic Forest, restinga comprises different phytophysiognomies where this family is a conspicuous element. Parque Estadual Paulo César Vinha (PEPCV) is an important area of restinga with various phytophysiognomies and serves as an interesting model for taxonomic studies about Melastomataceae. Thus, from October 2017 to April 2019, we conducted a taxonomic study of the family in this protected area and made ecological observations that have never been discussed for the group in this environment. We recorded 14 species and a preference for open, humid areas. The richest genera were Miconia and Pleroma. In addition to morphological and habitats information, we recorded three new occurrences for this protected area.

Distribution of Pleroma asperius (Melastomataceae) in Rio Grande do Sul, Brazil: spatial analysis for conservation strategie

Abstract Pleroma asperius is a shrubby Melastomataceae endemic to southern Brazil and threatened with extinction in the Rio Grande do Sul (RS) state. Aiming to better understand the distribution of the species in different environments in RS and contribute to its conservation, a literature review, searches on online platforms and field expeditions were carried out. From 270 records obtained, ninety-one presented location data and were treated as distinct occurrence points, six of them located in Conservation Units (CUs). Maps for P. asperius occurrence (82 non-overlapping points) were constructed, with layers referring to relief, biomes with phytogeographic regions, and hydrographic basins. Most points are below 50 m.a.s.l. in altitude (86.8%). The Pampa biome and Pioneer Formations have the highest percentages of occurrence points (74.4 and 71.9%, respectively). The interpolation of the occurrence points with environmental data characterized the preferential distribution of P. asperius in low-altitude areas, especially in wetlands and in the Pioneer Formations. These environments undergo intense changes by anthropic interventions. We draw attention to the low number of occurrence points in UCs. We still recommend to review the conservation status of P. asperius, include it for recomposing vegetation in degraded areas and create more CUs in the Pampa biome.

Flora of Espírito Santo: tribe Microlicieae (Melastomataceae)

Abstract Microlicieae is one of the most diverse tribes in Melastomataceae, comprising three genera: Microlicia (including the former Chaetostoma, Lavoisiera, Stenodon, and Trembleya), Poteranthera, and Rhynchanthera. It is characterized by anthers with a prolonged pedoconnective, capsular fruits, and reniform, oblong seeds with a foveolate testa. This study presents a taxonomic treatment for the species of Microlicieae in the state of Espírito Santo. A total of ten species were registered in two genera, Microlicia (9 spp.) and Rhynchanthera (1 sp.). Of these, three are new species of Microlicia: M. caparaoensis is endemic to the Caparaó National Park; M. capixaba and M. misteriosa are endemic to a single inselberg, the “Alto Misterioso”, in São Roque do Canaã. A fourth species was kept as Microlicia sp., since further studies will be necessary to confirm its identity. We also provide an identification key, morphological descriptions, distribution data, and comments for all species.

Melastomataceae of the Parque Natural Municipal de São Lourenço, Espírito Santo, Brazil

Abstract The Atlantic Forest is one of the diversity centers of Melastomataceae in the world, and studies have been showing the great richness of its species in Espírito Santo, a state that once was entirely covered by this phytogeographic domain. We present here a floristic survey of the species of Melastomataceae in a protected area in this state, the Municipal Natural Park of São Lourenço, located at the municipality of Santa Teresa. We also present an identification key for the species, detailed descriptions, comments on distribution, habitat and phenology, photographs and illustrations. A thorough sampling was based on several expeditions during 2019 and 2020; in addition, we analyzed all specimens collected in the area and deposited in the herbaria FLOR, HUEFS, MBM, MBML, NY, RB, UPCB, US and VIES. The family has 10 genera and 56 species in the area, with Miconia having 42 species, Pleroma six and the genera Aciotis, Acisanthera, Bertolonia, Chaetogastra, Henriettea, Meriania, Microlicia and Mouriri represented by only one species each.

The Melastoma dodecandrum genome and the evolution of Myrtales

Melastomataceae have abundant morphological diversity with high economic and ornamental merit in Myrtales. The phylogenetic position of Myrtales is still contested. Here, we report the first chromosome-level genome assembly of Melastoma dodecandrum in Melastomataceae. The assembled genome size was 299.81 Mb with a contig N50 value of 3.00 Mb. Genome evolution analysis indicated that M. dodecandrum, Eucalyptus grandis and Punica granatum were clustered into a clade of Myrtales and formed a sister group with the ancestor of fabids and malvids. We found that M. dodecandrum experienced four whole-genome polyploidization events: the ancient event was shared with most eudicots, one event was shared with Myrtales, and the other two events were unique to M. dodecandrum. Moreover, we identified MADS-box genes and found that the AP1-like genes expanded, and AP3-like genes might have undergone subfunctionalization. We found that the SUAR63-like genes and AG-like genes showed different expression patterns in stamens, which may be associated with heteranthery. In addition, we found that LAZY1-like genes were involved in the negative regulation of stem branching development, which may be related to its creeping features. Our study sheds new light on the evolution of Melastomataceae and Myrtales, which provides a comprehensive genetic resource for future research.

Connective appendages in Huberia bradeana (Melastomataceae) affect pollen release during buzz pollination

Floral structures, such as stamen appendages, play crucial roles in pollinator attraction, pollen release dynamics and, ultimately, the reproductive success of plants. The pollen-rewarding, bee buzz-pollinated flowers of Melastomataceae often bear conspicuous staminal appendages. Surprisingly, their functional role in the pollination process remains largely unclear. We use Huberia bradeana Bochorny & R. Goldenb. (Melastomataceae) with conspicuously elongated, twisted stamen appendages to investigate their functional role in the pollination process. We studied the effect of stamen appendages on pollinator behaviour and reproductive success by comparing manipulated flowers (appendages removed) with unmanipulated flowers. To assess bee pollinator behaviour, we measured three properties of buzzes (vibrations) produced by bees on Huberia flowers: frequency, duration and number of buzzes per flower visit. We measured male and female reproductive success by monitoring pollen release and deposition after single bee visits. Finally, we used artificial vibrations and laser vibrometry to assess how flower vibrational properties change with the removal of stamen appendages. Our results show that the absence of staminal appendages does not modify bee buzzing behaviour. Pollen release was higher in unmanipulated flowers, but stigmatic pollen loads differ only marginally between the two treatments. We also detected lower vibration amplitudes in intact flowers as compared to manipulated flowers in artificial vibration experiments. The presence of connective appendages are crucial in transmitting vibrations and assuring optimal pollen release. Therefore, we propose that the high diversity of colours, shapes and sizes of connective appendages in buzz-pollinated flowers may have evolved by selection through male fitness.

A nuclear phylogenomic study of the angiosperm order Myrtales, exploring the potential and limitations of the universal Angiosperms353 probe set

PREMISE

To further advance the understanding of the species-rich, economically and ecologically important angiosperm order Myrtales in the rosid clade, comprising nine families, approximately 400 genera and almost 14,000 species occurring on all continents (except Antarctica), we tested the Angiosperms353 probe kit.

METHODS

We combined high-throughput sequencing and target enrichment with the Angiosperms353 probe kit to evaluate a sample of 485 species across 305 genera (76% of all genera in the order).

RESULTS

Results provide the most comprehensive phylogenetic hypothesis for the order to date. Relationships at all ranks, such as the relationship of the early-diverging families, often reflect previous studies, but gene conflict is evident, and relationships previously found to be uncertain often remain so. Technical considerations for processing HTS data are also discussed.

CONCLUSIONS

High-throughput sequencing and the Angiosperms353 probe kit are powerful tools for phylogenomic analysis, but better understanding of the genetic data available is required to identify genes and gene trees that account for likely incomplete lineage sorting and/or hybridization events.

Evolution and biogeography of Memecylon

PREMISE

The woody plant group Memecylon (Melastomataceae) is a large clade occupying diverse forest habitats in the Old World tropics and exhibiting high regional endemism. Its phylogenetic relationships have been previously studied using ribosomal DNA with extensive sampling from Africa and Madagascar. However, divergence times, biogeography, and character evolution of Memecylon remain uninvestigated. We present a phylogenomic analysis of Memecylon to provide a broad evolutionary perspective of this clade.

METHODS

One hundred supercontigs of 67 Memecylon taxa were harvested from target enrichment. The data were subjected to coalescent and concatenated phylogenetic analyses. A timeline was provided for Memecylon evolution using fossils and secondary calibration. The calibrated Memecylon phylogeny was used to elucidate its biogeography and ancestral character states.

RESULTS

Relationships recovered by the phylogenomic analyses are strongly supported in both maximum likelihood and coalescent-based species trees. Memecylon is inferred to have originated in Africa in the Eocene and subsequently dispersed predominantly eastward via long-distance dispersal (LDD), although a reverse dispersal from South Asia westward to the Seychelles was postulated. Morphological data exhibited high levels of homoplasy, but also showed that several vegetative and reproductive characters were phylogenetically informative.

CONCLUSIONS

The current distribution of Memecylon appears to be the result of multiple ancestral LDD events. Our results demonstrate the importance of the combined effect of geographic and paleoclimatic factors in shaping the distribution of this group in the Old World tropics. Memecylon includes a number of evolutionarily derived morphological features that contribute to diversity within the clade.

Inverse Molecular Docking Study of NS3-Helicase and NS5-RNA Polymerase of Zika Virus as Possible Therapeutic Targets of Ligands Derived from Marcetia taxifolia and Its Implications to Dengue Virus

Dengue and Zika are two mosquito-borne diseases of great impact on public health around the world in tropical and subtropical countries. DENV and ZIKV belong to the Flaviviridae family and the Flavivirus genus. Currently, there are no effective therapeutic agents to treat or prevent these pathologies. The main objective of this work was to evaluate potential inhibitors from active compounds obtained from Marcetia taxifolia by performing inverse molecular docking on ZIKV-NS3-helicase and ZIKV-NS5-RNA polymerase as targets. This computational strategy is based on renormalizing the binding scores of the compounds to these two proteins, allowing a direct comparison of the results across the proteins. The crystallographic structures of the ZIKV-NS3-helicase and ZIKV-NS5-RNA-polymerase proteins share a great similarity with DENV homologous proteins. The P-loop active site of the crystallographic structure of ZIKV-NS3-helicase presents a high percentage of homology with the four dengue serotypes. It was found that most ligands of the active compounds (5,3'-dihydroxy-3,6,7,8,4'-pentamethoxyflavone (5DP); 5-hydroxy-3,6,7,8,3',4'-hexamethoxyflavone (5HH); myricetin-3-O-rhamnoside (M3OR)) from Marcetia taxifolia had a better affinity for ZIKV-NS3-helicase than for ZIKV-NS5-RNA polymerase, as indicated by the negative multiple active site correction (MASC) score, except for M3RG that showed a higher affinity for ZIKV-NS5-RNA polymerase. On the other hand, the AutoDock Vina scores showed that M3OR had the highest score value (-9.60 kcal/mol) and the highest normalized score (1.13) against ZIKV-NS3-helicase. These results in silico demonstrated that the nonstructural proteins NS3-helicase and NS5-RNA polymerase, which share similar molecular structures between the selected viruses, could become therapeutic targets for some bioactive compounds derived from Marcetia taxifolia.

Towards a new understanding of the division of labour in heterantherous flowers: the case of Pterolepis glomerata (Melastomataceae)

Pollen-flowers with heteromorphic stamens have been shown to promote an intrafloral division of labour as a solution to fitness costs arising from pollen consumption by bees, known as the pollen dilemma. Usually, the division is based on morphological differences in anther and pollen traits that correlate with stamen function: pollinating anthers are larger and contain more and higher-quality pollen grains than feeding anthers. Here, we present a new strategy based on a high investment in reward production and thus attraction, in the heterantherous Pterolepis glomerata, to overcome short flower longevity and maintain reproductive success. In P. glomerata small feeding anthers not only produced more pollen grains and more grains with cytoplasmic content, but also released more pollen than pollinating anthers after a single visit. This pattern was consistent until the end of floral anthesis, showing the existence of pollen-dosing mechanisms. Bees equally visited flowers with yellow feeding anthers and pollinating anthers with yellow connective appendages, indicating a visual similarity, as predicted by bee vision modelling. Our results demonstrate that the division of labour might have different outcomes. Instead of the classical expectation of more investment in reproductive pollen in pollinating stamens, P. glomerata invested more in attraction and reward in feeding stamens.

A two-tier bioinformatic pipeline to develop probes for target capture of nuclear loci with applications in Melastomataceae

PREMISE

Putatively single-copy nuclear (SCN) loci, which are identified using genomic resources of closely related species, are ideal for phylogenomic inference. However, suitable genomic resources are not available for many clades, including Melastomataceae. We introduce a versatile approach to identify SCN loci for clades with few genomic resources and use it to develop probes for target enrichment in the distantly related Memecylon and Tibouchina (Melastomataceae).

METHODS

We present a two-tiered pipeline. First, we identified putatively SCN loci using MarkerMiner and transcriptomes from distantly related species in Melastomataceae. Published loci and genes of functional significance were then added (384 total loci). Second, using HybPiper, we retrieved 689 homologous template sequences for these loci using genome-skimming data from within the focal clades.

RESULTS

We sequenced 193 loci common to Memecylon and Tibouchina. Probes designed from 56 template sequences successfully targeted sequences in both clades. Probes designed from genome-skimming data within a focal clade were more successful than probes designed from other sources.

DISCUSSION

Our pipeline successfully identified and targeted SCN loci in Memecylon and Tibouchina, enabling phylogenomic studies in both clades and potentially across Melastomataceae. This pipeline could be easily applied to other clades with few genomic resources.

Flower morphology is correlated with distribution and phylogeny in Bertolonia (Melastomataceae), an herbaceous genus endemic to the Atlantic Forest

Several centers of endemism have been proposed for Melastomataceae, particularly in Amazonia and Atlantic Forest. Despite the high degree of human-caused degradation in the last 500 years, the Atlantic Forest still presents some of the largest levels of diversity and endemism across all angiosperms. With several recently described species in the last decade, the knowledge on Bertolonia's distribution and morphological characterization has changed, with most new species found in northern Atlantic Forest and with different flower color patterns than the species from southern Atlantic Forest. We first tested the monophyly of the genus sampling over 85% of its species to generate a reliable phylogenetic hypothesis. Afterwards, we used Bertolonia as a model group to study distribution patterns and morphological evolution of lineages in the Atlantic Forest. Bertolonia is particularly interesting to address such questions because it is endemic to this domain, with species distributed either in the southern, central or northern portions of the Atlantic Forest. The second step of our work aimed to respond (1) Do closely related species endemic to Atlantic Forest tend to have similar distributions and share similar morphological traits? and (2) Are floral traits more conserved within clades than vegetative characters? We hypothesize that both (1) and (2) are true due to the low dispersal ability and consequent microendemic distribution of most species in the genus. Our results confirm the veracity of the proposed hypotheses. Three major groups were recovered in our analysis: marmorata, formosa and nymphaeifolia clades. Most species that occur in northern Atlantic Forest were recovered in the marmorata clade. Most species distributed in central Atlantic Forest were recovered in the formosa clade, and the ones from the southern Atlantic Forest in the nymphaeifolia clade. A similar pattern was recovered with reproductive characters reconstructed across the phylogeny. Generally, species with pink petals and cream-colored anthers with an extrorse pore occur in northern Atlantic Forest, and species with white petals and yellow anthers with an introrse or apical pore tend to occur in southern Atlantic Forest. Some vegetative characters also have evolutionary congruence and are restricted to one or few lineages, while other characters, such as the texture of the leaf blade surface, have a strong taxonomic value and are useful to identify species, but are not homologous. Our analysis also indicates that the division between southern and northern Atlantic Forest could also be related to ancient events, not only linked with recent phylogeographic patterns. Moreover, we suggest that the orientation of the anther pore in Bertolonia could be related with diversity of species and stability of its populations. In summary, we corroborate, based on the evolutionary history of Bertolonia, that closely related species endemic to Atlantic Forest tend to have similar distributions and share similar morphological floral traits.

Is dispersal mode a driver of diversification and geographical distribution in the tropical plant family Melastomataceae?

Species of plants with different life history strategies may differ in their seed dispersal mechanisms, impacting their distribution and diversification patterns. Shorter or longer distance dispersal is favored by different dispersal modes, facilitating (or constraining) population isolation, which can, in turn, impact speciation and species range sizes. While these associations are intuitive, few studies have explicitly tested these hypotheses for large clades of angiosperms. The plant family Melastomataceae is found on disparate habitats with different dispersal modes, representing a good model to address these questions. In this study, we reconstruct the phylogeny of Melastomataceae and gather data on their dispersal mode and range size to test the impact of dispersal mode on diversification and range size evolution. We found that abiotic dispersal is ancestral in the family, while biotic dispersal evolved multiple times. Species richness distribution is very similar across dispersal modes, although abiotically dispersed species tend to be relatively more diverse in seasonal environments. Range sizes across dispersal modes are not significantly different, although biotically dispersed species have slightly wider distributions. Model comparisons indicate that factors other than dispersal mode might have driven diversification heterogeneity. We did not find evidence for the role of dispersal mode driving diversification rates or range size in the Melastomataceae, suggesting a complex macroevolutionary scenario for this diverse angiosperm family. The bulk of changes to biotic dispersal coinciding with an increase in passerine diversification suggests a possible "past" key innovation in Melastomataceae. Future studies should investigate the role of other diversification drivers in the family and the relatively higher diversity of abiotically dispersed species in open habitats.

Melastomataceae das ilhas da Baía Babitonga, Santa Catarina, Brasil

Resumo Este trabalho é um estudo taxonômico da família Melastomataceae nas ilhas da Baía Babitonga, nordeste de Santa Catarina, região Sul do Brasil. A Baía compreende cerca de 160 km2 em um conjunto de 24 ilhas que abarcam cerca de 75% da área total de manguezais do estado de Santa Catarina. Foram efetuadas coletas entre 2004 e 2016, e coleções de herbários foram estudadas. Foram registradas 15 espécies, pertencentes a seis gêneros: Clidemia (2 spp.), Leandra (3 spp.), Miconia (5 spp.), Ossaea (1 sp.), Pleroma (1 sp.) e Tibouchina (3 spp.). São apresentadas chave de identificação para as espécies, descrições morfológicas, dados de distribuição geográfica e fenologia, e imagens das espécies.

Estratégias adaptativas foliares de Miconia nervosa (Melastomataceae) na Amazônia Matogrossense

Resumo A plasticidade fenotípica geralmente observada em caracteres morfológicos e anatômicos foliares pode ser influenciada por diversos fatores, como luminosidade, disponibilidade de nutrientes no solo, umidade e herbivoria, entre outros. Testamos essa plasticidade em Miconia nervosa (Melastomataceae) em um fragmento florestal no sul da Amazônia, Mato Grosso - Brasil, buscando verificar possíveis estratégias de aclimatação morfoanatômica à luminosidade. Coletamos folhas totalmente expandidas de 15 indivíduos adultos expostos diretamente à luz solar, nas margens de um lago, e 15 sob o sombreamento do dossel. Avaliamos quantitativamente oito variáveis morfológicas e seis anatômicas, das quais seis e quatro, respectivamente, diferiram significativamente entre folhas de sol e sombra. Morfologicamente, as folhas de sol apresentaram maior tamanho da lâmina foliar e do pecíolo e, anatomicamente, células epidérmicas com paredes levemente mais espessadas, maiores densidades e índice estomático. Folhas de sombra apresentaram epiderme significativamente mais espessa em ambas as faces. As folhas de M. nervosa apresentaram grau mediano a alto de plasticidade nas variáveis morfoanatômicas conforme índice de plasticidade fenotípica, com caracteres mistos de ambientes de sol e sombra. Sugerimos que a distribuição dos indivíduos de M. nervosa na floresta está relacionada à disponibilidade de luz e umidade do solo.

The effect of gut passage by waterbirds on the seed coat and pericarp of diaspores lacking "external flesh": Evidence for widespread adaptation to endozoochory in angiosperms

The widely accepted "endozoochory syndrome" is assigned to angiosperm diaspores with a fleshy, attractive tissue and implies the existence of adaptations for protection against digestion during gut passage. This syndrome has led diaspore fleshiness to be emphasized as the exclusive indicator of endozoochory in much of the ecology and biogeography research. Crucially, however, endozoochory in nature is not limited to frugivory, and diaspores without "external flesh" are commonly dispersed, often over long distances, via birds and mammals by granivory. A key question is: are such diaspores somehow less prepared from an architectural point of view to survive gut passage than fleshy diaspores? To answer this question, we selected 11 European angiosperm taxa that fall outside the classical endozoochory syndrome yet are known to be dispersed via endozoochory. We studied their seed coat/pericarp morphology and anatomy both before and after gut passage through granivorous waterfowl, and determined their seed survival and germinability. We found no fundamental differences in the mechanical architecture of the seed coat and pericarp between these plants dispersed by granivory and others dispersed by frugivory. Neither diaspore traits per se, nor dormancy type, were strong predictors of diaspore survival or degree of damage during gut passage through granivores, or of the influence of gut passage on germinability. Among our 11 taxa, survival of gut passage is enabled by the thick cuticle of the exotesta or epicarp; one or several lignified cell layers; and diverse combinations of other architectural elements. These protection structures are ubiquitous in angiosperms, and likely to have evolved in gymnosperms. Hence, many angiosperm diaspores, dry or fleshy, may be pre-adapted to endozoochory, but with differing degrees of specialization and adaptation to dispersal mechanisms such as frugivory and granivory. Our findings underline the broad ecological importance of "non-classical endozoochory" of diaspores that lack "external flesh".

Systematics and relationships of Tryssophyton (Melastomataceae), with a second species from the Pakaraima Mountains of Guyana

The systematics of Tryssophyton, herbs endemic to the Pakaraima Mountains of western Guyana, is reviewed and Tryssophyton quadrifolius K.Wurdack & Michelang., sp. nov. from the summit of Kamakusa Mountain is described as the second species in the genus. The new species is distinguished from its closest relative, Tryssophyton merumense, by striking vegetative differences, including number of leaves per stem and leaf architecture. A phylogenetic analysis of sequence data from three plastid loci and Melastomataceae-wide taxon sampling is presented. The two species of Tryssophyton are recovered as monophyletic and associated with mostly Old World tribe Sonerileae. Fruit, seed and leaf morphology are described for the first time, biogeography is discussed and both species are illustrated.

Characterization of the complete chloroplast genome sequence of Blastus cochinchinensis (Melastomataceae)

Blastus Lour. belongs to tribe Sonerileae (Melastomataceae), comprising about 18 species worldwide. Herein, we presented, assembled, and annotated the first complete chloroplast genome of Blastus (B. cochinchinensis). The complete chloroplast genome (cp) size of B. cochinchinensis was 156,005 bp in length, containing a pair of 26,812 bp inverted repeat (IR) regions, which were separated by a large single-copy region (LSC) 85,926 bp and a small single-copy (SSC) region 16,455 bp. The overall GC content of the genome was 37.0%. The whole genome contained 129 unique genes, including 81 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. The phylogenetic analysis showed that B. cochinchinens was sister to Barthea barthei. The present study provided B. cochinchinensis genomic information that may be found useful in conservation and molecular phylogenetic studies on Blastus.

Phylogeny, host use, and diversification in the moth family Momphidae (Lepidoptera: Gelechioidea)

Insect herbivores and their hostplants constitute much of Earth's described biological diversity, but how these often-specialized associations diversify is not fully understood. We combined detailed hostplant data and comparative phylogenetic analyses of the lepidopteran family Momphidae to explore how shifts in the use of hostplant resources, not just hostplant taxon, contribute to the diversification of a phytophagous insect lineage. We inferred two phylogenetic hypotheses emphasizing relationships among species in the nominate genus, Mompha Hübner. A six-gene phylogeny was constructed with reared exemplars and collections from hostplants in the family Onagraceae from western and southwestern USA, and a cytochrome c oxidase subunit 1 (COI) phylogeny was inferred from collections and publicly available accessions in the Barcode of Life Data System. Species delimitation analyses combined with morphological data revealed ca. 56 undescribed species-level taxa, many of which are hostplant specialists on Onagraceae in the southwestern USA. Our phylogenetic reconstructions divided Momphidae into six major clades: 1) an Onagraceae flower- and fruit-boring clade, 2) a Melastomataceae-galling clade, 3) a leafmining clade A, 4) a leafmining clade B, 5) a Zapyrastra Meyrick clade, and 6) a monobasic lineage represented by Mompha eloisella (Clemens). Ancestral trait reconstructions using the COI phylogeny identified leafmining on Onagraceae as the ancestral state for Momphidae. Our study finds that shifts along three hostplant resource axes (plant taxon, plant tissue type, and larval feeding mode) have contributed to the evolutionary success and diversification of momphids.

Nothodissotis (Melastomataceae), a new genus from Atlantic Central Africa, including the new species N.alenensis from Equatorial Guinea

Based on morphological and phylogenetic evidence, a new genus of Melastomataceae (Melastomateae), Nothodissotis Veranso-Libalah & G.Kadereit, gen. nov., is described from Atlantic Central Africa. Nothodissotis is distinguished from other African Melastomateae genera by its calyx-lobes that are notched at apex and asymmetrical (vs. entire and symmetrical). Nothodissotis includes two species: the type species N.barteri (Hook.f.) Veranso-Libalah & G.Kadereit, comb. nov. (syn. Dissotisbarteri Hook.f.), and the new species N.alenensis Veranso-Libalah & O. Lachenaud, sp. nov., described and illustrated here. Both species are restricted to open vegetation on rock outcrops within the forested region of Atlantic Central Africa. Nothodissotisbarteri has a scattered distribution in Cameroon, Equatorial Guinea, Gabon and Príncipe Island, while N.alenensis is endemic to the Monte Alén massif in Equatorial Guinea, an area where N.barteri does not occur. Nothodissotisalenensis differs from N.barteri by its hypanthium bearing sessile appendages with penicillate hairs (vs. stalked stellate appendages) and its staminal appendages that are much smaller in antepetalous than in antesepalous stamens (vs. subequal in all stamens). The conservation status of both N.barteri and N.alenensis is assessed as Vulnerable in accordance with IUCN criteria.

Acylated Flavonoid Glycosides are the Main Pigments that Determine the Flower Colour of the Brazilian Native Tree Tibouchina pulchra (Cham.) Cogn

Tibouchina pulchra (Cham.) Cogn. is a plant native to Brazil whose genus and family (Melastomataceae) are poorly studied with regards to its metabolite profile. Phenolic pigments of pink flowers were studied by ultra-performance liquid chromatography with a photodiode array detector and electrospray ionization quadrupole time-of-flight mass spectrometry. Therein, twenty-three flavonoids were identified with eight flavonols isolated by preparative high-performance liquid chromatography and analysed by one- and two-dimensional nuclear magnetic resonance. Kaempferol derivatives were the main flavonols, encompassing almost half of the detected compounds with different substitution patterns, such as glucoside, pentosides, galloyl-glucoside, p-coumaroyl-glucoside, and glucuronide. Concerning the anthocyanins, petunidin p-coumaroyl-hexoside acetylpentoside and malvidin p-coumaroyl-hexoside acetylpentoside were identified and agreed with previous reports on acylated anthocyanins from Melastomataceae. A new kaempferol glucoside was identified as kaempferol-(2''-O-methyl)-4'-O-α-d-glucopyranoside. Moreover, twelve compounds were described for the first time in the genus with five being new to the family, contributing to the chemical characterisation of these taxa.

Beyond buzz-pollination - departures from an adaptive plateau lead to new pollination syndromes

Pollination syndromes describe recurring adaptation to selection imposed by distinct pollinators. We tested for pollination syndromes in Merianieae (Melastomataceae), which contain bee- (buzz-), hummingbird-, flowerpiercer-, passerine-, bat- and rodent-pollinated species. Further, we explored trait changes correlated with the repeated shifts away from buzz-pollination, which represents an 'adaptive plateau' in Melastomataceae. We used random forest analyses to identify key traits associated with the different pollinators of 19 Merianieae species and estimated the pollination syndromes of 42 more species. We employed morphospace analyses to compare the morphological diversity (disparity) among syndromes. We identified three pollination syndromes ('buzz-bee', 'mixed-vertebrate' and 'passerine'), characterized by different pollen expulsion mechanisms and reward types, but not by traditional syndrome characters. Further, we found that 'efficiency' rather than 'attraction' traits were important for syndrome circumscription. Contrary to syndrome theory, our study supports the pooling of different pollinators (hummingbirds, bats, rodents and flowerpiercers) into the 'mixed-vertebrate' syndrome, and we found that disparity was highest in the 'buzz-bee' syndrome. We conclude that the highly adaptive buzz-pollination system may have prevented shifts towards classical pollination syndromes, but provided the starting point for the evolution of a novel set of distinct syndromes, all having retained multifunctional stamens that provide pollen expulsion, reward and attraction.

A new species of Fordiophyton (Sonerileae, Melastomataceae) from Yunnan, China

Fordiophytonjinpingense (Melastomataceae; Sonerileae), a species occurring in south-eastern Yunnan, China, is described as new, based on morphological and molecular data. Phylogenetic analyses, based on nrITS sequence data, showed that, except F.breviscapum, all species sampled in Fordiophyton formed a strongly supported clade in which two geographical lineages were recovered. The generic placement of F.jinpingense is well supported by phylogenetic analyses and a character combination of 4-merous flowers, distinctly dimorphic stamens and the connectives basally not calcarate. Molecular divergence and morphological evidence indicate that F.jinpingense is well separated from other members of the genus, thus justifying its recognition as a distinct species. Fordiophytonjinpingense is phylogenetically closest to F.repens, but differs markedly from the latter in stem morphology (short, obtusely 4-sided vs. long, 4-angular), habit (erect vs. creeping), leaf size (6-16.5 × 4.5-13 cm vs. 4-7.5 × 4-6.5 cm) and flower number per inflorescence (5-13 vs. 3-6).

Flora do Espírito Santo: Bertolonia (Melastomataceae)

Resumo Este estudo trata das espécies de Bertolonia (Melastomataceae) encontradas no estado do Espírito Santo, Brasil. O trabalho é baseado em análise morfológica de coleções depositadas em herbários, bibliografia específica e coletas de campo. Um total de nove espécies foram registradas, a maioria endêmica no estado, além de uma nova espécie (B. michelangeliana). São apresentadas uma chave de identificação atualizada, descrições, status de conservação e comentários sobre a distribuição das espécies.

Melastomataceae na Área de Proteção Ambiental Mestre Álvaro, Serra, Espírito Santo, Brasil

Resumo Melastomataceae é a sexta família de angiospermas com maior número de espécies no Brasil e a sétima no Espírito Santo, apesar deste ainda apresentar poucos trabalhos relacionados a esta família. O objetivo do presente estudo foi realizar o levantamento florístico-taxonômico de Melastomataceae na Área de Proteção Ambiental Mestre Álvaro (APAMA), localizada no município da Serra, Região Metropolitana de Vitória, um remanescente de Floresta Atlântica que apresenta importantes fragmentos florestais em estágios avançados de regeneração. Expedições de campo foram realizadas entre 2012 e 2014. Também foram analisados espécimes depositados nos herbários VIES, MBML e SP. Na APAMA foram encontradas 26 espécies distribuídas em 10 gêneros, um acréscimo de 22 espécies em relação ao Plano de Manejo da APAMA, o único inventário da flora existente para a área. Behuria mestrealvarensis, endêmica da APAMA, Bertolonia ruschiana e Leandra triantha, endêmicas do Espírito Santo, são consideradas ameaçadas de extinção. A maior riqueza de espécies foi encontrada na Floresta Ombrófila Densa Montana, com 22 espécies, das quais 18 são exclusivas deste tipo de vegetação. São apresentados chave ilustrada de identificação, descrições, comentários sobre a distribuição geográfica e estado de conservação das espécies.

Microlicieae (Melastomataceae) no município de Mucugê, Chapada Diamantina, Bahia, Brasil

Resumo O presente estudo fornece o tratamento taxonômico das espécies de Microlicieae para o município de Mucugê, Chapada Diamantina, Bahia, Brasil. Foram catalogadas 27 espécies distribuídas nos gêneros Microlicia (24 espécies), Lavoisiera (L. harleyi e L. nervulosa) e Trembleya (T. parviflora). Com exceção de M. fasciculata, M. viminalis e T. parviflora, as demais espécies encontradas em Mucugê são endêmicas da Chapada Diamantina. Entre as espécies de Microlicia, quatro foram recentemente descritas e outras quatro ainda necessitam de estudos complementares para sua identificação. Anteras poliesporangiadas foram descritas pela primeira vez para 11 espécies de Microlicia. As espécies de Microlicieae ocupam áreas de campo rupestre em altitudes entre 900-1.500 m, em solos arenosos ou pedregosos, às vezes associadas a cursos d'água.

The ontogenetic bases for variation in ovary position in Melastomataceae

PREMISE OF THE STUDY

Although the ovary position is considered a stable character in angiosperms, Melastomataceae species have perigynous flowers in which the ovary varies from superior to inferior. Thus, we investigated the ontogenetic process involved in variation of the ovary position in Melastomataceae. We focused on histogenesis of the floral apex in search of developmental patterns for each type of ovary position.

METHODS

Six species in which the ovary varies from superior to inferior were chosen: Henriettea saldanhae, Leandra melastomoides, Miconia dodecandra, Microlicia euphorbioides, Rhynchanthera grandiflora, and Tibouchina clinopodifolia. Buds and flowers were processed for surface and histological examinations.

KEY RESULTS

The floral apex changes from convex to concave, resulting in a perigynous hypanthium. Cell divisions in the margins of the floral apex form an annular intercalary meristem that elevates the base of the primordia of almost all whorls. The joint growth of the carpel base with the gynoecial hypanthium originates semi-inferior ovaries in Leandra melastomoides, Miconia dodecandra, and Tibouchina clinopodifolia and inferior ovaries in Henriettea saldanhae. In Microlicia euphorbioides and Rhynchanthera grandiflora, the carpels are not affected by this hypanthial growth; flowers have a superior ovary.

CONCLUSIONS

Changes in ovary position of Melastomataceae are due to intercalary meristematic activity, which is one of the main mechanisms for the origin of morphological innovations among plants. Our data illustrate the importance of the intercalary meristems in floral development, and we discuss the implications of this ontogenetic model for understanding the evolution of ovary position in Melastomataceae.

Stochastic losses of fire-dependent endemic herbs revealed by a 65-year chronosequence of dispersal-limited woody plant encroachment

The factors responsible for maintaining diverse groundcover plant communities of high conservation value in frequently burned wet pine savannas are poorly understood. While most management involves manipulating extrinsic factors important in maintaining species diversity (e.g., fire regimes), most ecological theory (e.g., niche theory and neutral theory) examines how traits exhibited by the species promote species coexistence. Furthermore, although many ecologists focus on processes that maintain local species diversity, conservation biologists have argued that other indices (e.g., phylogenetic diversity) are better for evaluating assemblages in terms of their conservation value. I used a null model that employed beta‐diversity calculations based on Raup–Crick distances to test for deterministic herbaceous species losses associated with a 65‐year chronosequence of woody species encroachment within each of three localities. I quantified conservation value of assemblages by measuring taxonomic distinctness, endemism, and floristic quality of plots with and without woody encroachment. Reductions in herb species richness per plot attributable to woody encroachment were largely stochastic, as indicated by a lack of change in the mean or variance in beta‐diversity caused by woody encroachment in the savannas studied here. Taxonomic distinctness, endemism, and floristic quality (when summed across all species) were all greater in areas that had not experienced woody encroachment. However, when corrected for local species richness, only average endemism and floristic quality of assemblages inclusive of herbs and woody plants were greater in areas that had not experienced woody encroachment, due to the more restricted ranges and habitat requirements of herbs. Results suggest that frequent fires maintain diverse assemblages of fire‐dependent herb species endemic to the region. The stochastic loss of plant species, irrespective of their taxonomic distinctness, to woody encroachment suggests that the relevance of niche partitioning or phylogenetic diversity to the management of biodiversity in wet pine savannas is minimal.

Flora das cangas da Serra dos Carajás, Pará, Brasil: Melastomataceae

Resumo Apresenta-se um tratado taxonômico para a família Melastomataceae nas áreas de cangas da Serra dos Carajás. Foram registradas 42 espécies distribuídas em 18 gêneros, sendo Miconia o mais rico, com 20 espécies, seguido de Clidemia com três espécies. O gênero monotípico Brasilianthus (B. carajensis) é considerado endêmico da região de Carajás, assim como uma espécie de Pleroma. Este trabalho apresenta descrições morfológicas, chaves de identificação para gêneros e espécies, ilustrações, distribuição geográfica e comentários para as espécies tratadas.

Three new species of Bertolonia (Melastomataceae) from Espírito Santo, Brazil

We describe and illustrate three new species of Bertolonia, all endemic to the state of Espírito Santo, Brazil. Bertolonia duasbocaensis and B. macrocalyx occur close to each other, in the municipalities of Cariacica and Viana. Bertolonia ruschiana has a wider distribution, occurring in the municipalities of Santa Leopoldina, Santa Maria de Jetibá and Santa Teresa. The first two species are classified as critically endangered (CR), and the latter as endangered (EN). We also present an identification key for the species of Bertolonia that occur in Espírito Santo.

Characterization and Comparative Expression Profiling of Browning Response in Medinilla formosana after Cutting

Plant browning is a recalcitrant problem for in vitro culture and often leads to poor growth of explants and even failure of tissue culture. However, the molecular mechanisms underlying browning-induced physiological processes remain unclear. Medinilla is considered one of the most difficult genera for tissue culture owning to its severe browning. In the present study, intact aseptic plantlets of Medinilla formosana Hayata previously obtained by ovary culture, were used to explore the characteristics and molecular mechanism of the browning response. Successive morphological and anatomical observations after cutting showed that the browning of M. formosana was not lethal but adaptive. De novo transcriptome and digital gene expression (DGE) profiling using Illumina high-throughput sequencing were then used to explore molecular regulation after cutting. About 7.5 million tags of de novo transcriptome were obtained and 58,073 unigenes were assembled and annotated. A total of 6,431 differentially expressed genes (DEGs) at three stages after cutting were identified, and the expression patterns of these browning-related genes were clustered and analyzed. A number of putative DEGs involved in signal transduction and secondary metabolism were particularly studied and the potential roles of these cutting-responsive mRNAs in plant defense to diverse abiotic stresses are discussed. The DGE profiling data were also validated by quantitative RT-PCR analysis. The data obtained in this study provide an excellent resource for unraveling the molecular mechanisms of browning processes during in vitro tissue culture, and lay a foundation for future studies to inhibit and eliminate browning damage.

A tribo Miconieae (Melastomataceae) no Parque Estadual do Biribiri, Diamantina, Minas Gerais, Brasil

Resumo A tribo Miconieae no Parque Estadual do Biribiri está representada por 23 espécies e cinco gêneros. Miconia é o gênero mais numeroso, com 14 espécies, seguido de Leandra com quatro, Clidemia com três e Tococa e Ossaea com uma espécie cada. As espécies ocorrem na maioria das fitofisionomias do parque, com um maior número de espécies nas formações florestais. Chave de identificação para as espécies, descrições e dados de distribuição geográfica são fornecidos, assim como ilustrações dos táxons pouco representados na literatura.

The first complete plastid genomes of Melastomataceae are highly structurally conserved

Background

In the past three decades, several studies have predominantly relied on a small sample of the plastome to infer deep phylogenetic relationships in the species-rich Melastomataceae. Here, we report the first full plastid sequences of this family, compare general features of the sampled plastomes to other sequenced Myrtales, and survey the plastomes for highly informative regions for phylogenetics.

Methods

Genome skimming was performed for 16 species spread across the Melastomataceae. Plastomes were assembled, annotated and compared to eight sequenced plastids in the Myrtales. Phylogenetic inference was performed using Maximum Likelihood on six different data sets, where putative biases were taken into account. Summary statistics were generated for all introns and intergenic spacers with suitable size for polymerase chain reaction (PCR) amplification and used to rank the markers by phylogenetic information.

Results

The majority of the plastomes sampled are conserved in gene content and order, as well as in sequence length and GC content within plastid regions and sequence classes. Departures include the putative presence of rps16 and rpl2 pseudogenes in some plastomes. Phylogenetic analyses of the majority of the schemes analyzed resulted in the same topology with high values of bootstrap support. Although there is still uncertainty in some relationships, in the highest supported topologies only two nodes received bootstrap values lower than 95%.

Discussion

Melastomataceae plastomes are no exception for the general patterns observed in the genomic structure of land plant chloroplasts, being highly conserved and structurally similar to most other Myrtales. Despite the fact that the full plastome phylogeny shares most of the clades with the previously widely used and reduced data set, some changes are still observed and bootstrap support is higher. The plastome data set presented here is a step towards phylogenomic analyses in the Melastomataceae and will be a useful resource for future studies.

O clado Merianthera e as tribos Merianieae e Microliceae (Melastomataceae) na Serra Negra, Minas Gerais

Resumo Apresenta-se um estudo taxonômico do clado Merianthera e das tribos Merianieae e Microlicieae (Melastomataceae) na Serra Negra, localizada no Complexo da Mantiqueira, região sul da Zona da Mata de Minas Gerais, Brasil. O clado Merianthera está representado por Behuria parvifolia, Huberia nettoana e Cambessedesia hilariana, Merianieae está representada apenas por Meriania claussenii, enquanto Microlicieae está representada por Lavoisiera imbricata, Microlicia serpyllifolia, Rhynchanthera dichotoma, Trembleya elegans, Trembleya parviflora e Trembleya phlogiformis. A região vem sofrendo impactos devido à plantação de Pinus e Eucalyptus, especulação imobiliária, visitação desorganizada, coleta ilegal de plantas, bem como o aumento das áreas de pastagem, de modo que várias espécies se encontram sob constante ameaça. Em relação à conservação, deve-se ressaltar as espécies B. parvifolia, H. nettoana e M. claussenii, provavelmente ameaçadas de extinção a nível regional ou nacional. No presente artigo são apresentadas chaves de identificação, descrições, ilustrações, informações sobre distribuição geográfica e comentários morfológicos para os táxons desses grupos representados na Serra Negra.

Melastomataceae na Serra dos Pireneus, Goiás, Brasil

Resumo A Serra dos Pireneus, localizada na porção centro-oeste do estado de Goiás, está representada prioritariamente por fisionomias das formações campestres e savânicas, onde a família é bastante diversa. O presente estudo apresenta o tratamento sistemático das 77 espécies de Melastomataceae catalogadas para a Serra dos Pireneus. Espécimes depositados nos herbários CEN, ESA, HUEG, HUFU, IBGE, K, MBM, RB, SP, UB, UEC e UFG foram analisados. Chave de identificação para as espécies, descrições com comentários taxonômicos e ilustrações de caracteres diagnósticos são fornecidos.

Behuria, Bertolonia, Cambessedesia, Huberia e Mouriri, e chave para identificação de gêneros de Melastomataceae no Estado do Paraná

Resumo A família Melastomataceae possui 22 gêneros e 150 espécies no estado do Paraná. Tratamentos com descrições e chaves de identificação já foram publicados para 17 destes gêneros. Neste trabalho, são apresentados os tratamentos taxonômicos dos cinco gêneros faltantes, com nove espécies: Behuria insignis, Bertolonia acuminata, B. margaritacea, B. mosenii, B. paranaensis, Cambessedesia espora, C. hilariana, Huberia semiserrata e Mouriri chamissoana. Também é apresentada uma chave de identificação para os gêneros de Melastomataceae ocorrentes no Paraná, além de ilustrações dos gêneros apresentados neste trabalho.

Economia de pólen favorecida pela heteranteria em Desmocelis villosa (Melastomataceae)

Resumo A heteranteria sempre despertou interesse quanto à sua funcionalidade. As flores de Desmocelis villosa (Melastomataceae), possuem estames dimorfos, sendo um grupo composto por cinco anteras amarelas e o outro por cinco anteras de cor púrpura. O presente estudo avaliou se a heteranteria promove divisão de trabalho nessa espécie. Foi realizado um experimento com remoção de anteras de cada tipo para se comparar a taxa de visitação por abelhas. Ao vibrar o conjunto de estames, as abelhas coletavam o pólen das anteras amarelas enquanto as de cor púrpura depositavam seu pólen na parte final do corpo das mesmas em uma posição próxima ao estigma favorecendo a polinização. Flores com anteras amarelas apresentaram maiores taxas de visitação que aquelas que tinham apenas anteras púrpuras. Nesta espécie a heteranteria se mostra como uma estratégia eficaz na economia do pólen utilizado com o serviço de polinização, pois embora os dois tipos de anteras apresentem alta porcentagem de grãos viáveis, as anteras amarelas apresentam significativamente menos grãos de pólen que as púrpuras, indicando que a planta estrategicamente reserva a maior parte do pólen para a reprodução sexuada.

Sonerila nairii (Melastomataceae) - a new species from the southern Western Ghats, India

The new species Sonerila nairii (Melastomataceae) is here described from Pothumala of the Nelliampathy hill ranges of Western Ghats of Kerala, India. Morphologically it most closely resembles Sonerila erecta and Sonerila pulneyensis from which differs by the form of the stem, leaves, peduncle, pedicel, inflorescence, pubescence of the stem, leaves and hypanthium, and by the form of stamens and stigma.

Primers for low-copy nuclear genes in the Melastomataceae

PREMISE OF THE STUDY

Low-copy nuclear gene primers were developed for phylogenetic studies across the Melastomataceae.

METHODS AND RESULTS

Total genomic libraries from eight species in the Melastomataceae along with one transcriptome were used for marker identification and primer design. Eight exon-primed intron-crossing markers were amplified with success in taxa of nine tribes in the Melastomataceae. The new markers were directly sequenced for eight samples of closely related species of Miconia (Chaenanthera clade) in the tribe Miconieae. The DNA sequences for the eight loci ranged from 660 to 818 aligned base pairs. Compared with four commonly used markers in other studies, the loci developed here had a higher number of variable sites than plastid spacers (7-16 vs. 26-45) and comparable variation to the ribosomal spacers (28-39).

CONCLUSIONS

The novel primer pairs should be useful for a broad range of studies of systematics and evolution in the diverse Melastomataceae.

Divergence times, historical biogeography, and shifts in speciation rates of Myrtales

We examine the eudicot order Myrtales, a clade with strong Gondwanan representation for most of its families. Although previous phylogenetic studies greatly improved our understanding of intergeneric and interspecific relationships within the order, our understanding of inter-familial relationships still remains unresolved; hence, we also lack a robust time-calibrated chronogram to address hypotheses (e.g., biogeography and diversification rates) that have implicit time assumptions. Six loci (rbcL, ndhF, matK, matR, 18S, and 26S) were amplified and sequenced for 102 taxa across Myrtales for phylogenetic reconstruction and ten fossil priors were utilized to produce a chronogram in BEAST. Combretaceae is identified as the sister clade to all remaining families with moderate support, and within the latter clade, two strongly supported groups are seen: (1) Onagraceae+Lythraceae, and (2) Melastomataceae+the Crypteroniaceae, Alzateaceae, Penaeaceae clade along with Myrtaceae+Vochysiaceae. Divergence time estimates suggest Myrtales diverged from Geraniales ∼124Mya during the Aptian of the Early Cretaceous. The crown date for Myrtales is estimated at ∼116Mya (Albian-Aptian). BioGeoBEARS showed significant improvement in the likelihood score when the "jump dispersal" parameter was added. South America and/or Africa are implicated as important ancestral areas in all deeper nodes. BAMM analyses indicate that the best configuration included three significant shifts in diversification rates within Myrtales: near the crown of Melastomataceae (∼67-64Mya), along the stem of subfamily Myrtoideae (Myrtaceae; ∼75Mya), and along the stem of tribe Combreteae (Combretaceae; ∼50-45Mya). Issues with conducting diversification analyses more generally are examined in the context of scale, taxon sampling, and larger sets of phylogenetic trees.

A tribo Microlicieae (Melastomataceae) no estado do Paraná

Os gêneros Chaetostoma, Lavoisiera, Microlicia, Rhynchanthera e Trembleya são os representantes da tribo Microlicieae no estado do Paraná, com nove espécies: C. armatum, L. imbricata, L. pulchella, M. myrtoidea, R. brachyrhyncha, R. cordata, R dichotoma, T. parviflora e T. phlogiformis. Neste trabalho foi elaborado o tratamento taxonômico para as espécies de Microlicieae no estado, com chaves de identificação, descrições morfológicas, comentários, ilustrações e informações sobre distribuição geográfica das espécies, além da lista de materiais examinados.

Aciotis, Acisanthera, Marcetia e Pterolepis (Melastomeae-Melastomataceae) no estado do Rio de Janeiro

É apresentado o tratamento taxonômico para os gêneros Aciotis, Acisanthera, Marcetia e Pterolepis. (Melastomeae, Melastomataceae) no estado do Rio de Janeiro. Cada um dos quatro gêneros apresentados está representado por uma única espécie no estado: Aciotis paludosa, Acisanthera variabilis, Marcetia taxifolia e Pterolepis glomerata. Com este estudo se atualizou a lista de espécies para a flora do estado do Rio de Janeiro, removendo seis espécies equivocadamente listadas. Um tratamento taxonômico à parte está sendo providenciado para as espécies de Tibouchina sensu lato, que serão segregadas entre os gêneros Chaetogastra e Pleroma (que inclui Itatiaia). O tratamento taxonômico apresentado para os gêneros inclui chave de identificação, descrições, comentários taxonômicos, informações sobre distribuição geográfica, categorização de risco de extinção segundo os critérios da IUCN, lista de materiais examinados e ilustrações.

De novo assembly of Eugenia uniflora L. transcriptome and identification of genes from the terpenoid biosynthesis pathway

Pitanga (Eugenia uniflora L.) is a member of the Myrtaceae family and is of particular interest due to its medicinal properties that are attributed to specialized metabolites with known biological activities. Among these molecules, terpenoids are the most abundant in essential oils that are found in the leaves and represent compounds with potential pharmacological benefits. The terpene diversity observed in Myrtaceae is determined by the activity of different members of the terpene synthase and oxidosqualene cyclase families. Therefore, the aim of this study was to perform a de novo assembly of transcripts from E. uniflora leaves and to annotation to identify the genes potentially involved in the terpenoid biosynthesis pathway and terpene diversity. In total, 72,742 unigenes with a mean length of 1048bp were identified. Of these, 43,631 and 36,289 were annotated with the NCBI non-redundant protein and Swiss-Prot databases, respectively. The gene ontology categorized the sequences into 53 functional groups. A metabolic pathway analysis with KEGG revealed 8,625 unigenes assigned to 141 metabolic pathways and 40 unigenes predicted to be associated with the biosynthesis of terpenoids. Furthermore, we identified four putative full-length terpene synthase genes involved in sesquiterpenes and monoterpenes biosynthesis, and three putative full-length oxidosqualene cyclase genes involved in the triterpenes biosynthesis. The expression of these genes was validated in different E. uniflora tissues.