Species Of Myrcia Research Articles

Myrcia cupreiflora (Myrtaceae), a new species from the Brazilian state of Rio de Janeiro

A new species of Myrcia (Myrtaceae) from the Brazilian Atlantic Forest in the state of Rio de Janeiro is described and illustrated. The species is recognizable by its strongly bullate leaf blades, long, axillary and terminal, coppery and strigose inflorescences and calyces completely fused in the flower buds, tearing deeply vertically into 4–5 homogeneous sepals at anthesis. We herein provide a morphological description of the new species along with taxonomic notes, preliminary conservation status, illustrations, and a map of occurrence records.

Exploring the Potential of Myrcia Genus Essential Oils: A Review of Biological Activities and Recent Advances.

The present study provides a comprehensive analysis of the chemical composition of essential oils from species of the Myrcia genus and their applications. The compiled results highlight the chemical diversity and biological activities of these oils, emphasizing their potential importance for various therapeutic and industrial applications. The findings reveal that Myrcia essential oils present a variety of bioactive compounds, such as monoterpenes and sesquiterpenes, which demonstrate antimicrobial activities against a range of microorganisms, including Gram-positive and Gram-negative bacteria, as well as yeasts. Furthermore, this study highlights the phytotoxic activity of these oils, indicating their potential for weed control. The results also point to the insecticidal potential of Myrcia essential oils against a range of pests, showing their viability as an alternative to synthetic pesticides. Additionally, species of the genus Myrcia have demonstrated promising hypoglycemic effects, suggesting their potential in diabetes treatment. This comprehensive synthesis represents a significant advancement in understanding Myrcia essential oils, highlighting their chemical diversity and wide range of biological activities. However, the need for further research is emphasized to fully explore the therapeutic and industrial potential of these oils, including the identification of new compounds, understanding of their mechanisms of action, and evaluation of safety and efficacy in different contexts.

Sinopse de Myrcia (Myrtaceae) no estado de Pernambuco, Brasil

Abstract: The present study is a synopsis of the species of Myrcia occurring in Pernambuco, Brazil. We recorded 30 species distributed in eight sections: M. sect. Aguava (4), Myrcia sect. Aulomyrcia (9), M. sect. Calyptranthes (3), M. sect. Gomidesia (5), M. sect. Myrcia (4), M. sect. Reticulosae (2), M. sect. Sympodiomyrcia (2) and M. sect. Tomentosae (1), beyond Myrcia sp. which has not been included in any section yet. Myrcia laricina (O. Berg) Burret ex Luetzelb. and M. hirtiflora DC. are new records for the State. Myrcia arenaria had the first record for humid forest in the municipality of Brejo da Madre de Deus. This study provides an identification key, comments on morphological distinction, geographic distribution and habitat for all taxa. In addition, distribution maps, photographic plates with the distinctive characteristics of the species are included and the updating names of Calyptranthes, Gomidesia and Marlierea under Myrcia.

Leaf morphology and anatomy in Myrcia sect. Aulomyrcia (Myrtaceae): species circumscription and characterization of clades

Myrcia DC., a diverse neotropical genus of Myrtaceae, encompasses 793 species. However, species of Myrcia are similar and difficult to distinguish. In Myrcia sect. Aulomyrcia (O. Berg) Griseb., leaf features help distinguishing clades and species. Our aim is to provide leaf data for species of M. sect. Aulomyrcia’s clades F and G. We sampled 31 specimens of 13 species of Myrcia sect. Aulomyrcia ( Myrcia amazonica DC., Myrcia eumecephylla (O. Berg) Nied., Myrcia hexasticha Kiaersk., Myrcia insularis Gardner, Myrcia magna D. Legrand, Myrcia micropetala (Mart.) Nied., Myrcia neodimorpha E. Lucas & C.E. Wilson, Myrcia neoestrellensis E. Lucas & C.E. Wilson, Myrcia obversa (D. Legrand) E. Lucas & C.E. Wilson, Myrcia pyrifolia (Desv.) Nied., Myrcia riodocensis G.M. Barroso & Peixoto, Myrcia subobliqua (Benth.) Nied., and Myrcia tetraphylla Sobral) . Samples were subjected to sectioning and staining techniques for morphological and anatomical analysis through stereo and light microscopy. Leaf blade and petiole morphological and anatomical features were described carefully for the first time for these 13 species. We provided an identification key based on leaf features. Our findings are discussed in the light of Myrcia sect. Aulomyrcia systematics. We comment of the significance of petiolar and blade features, such as trichomes types and location, phyllotaxis, rhytidome peeling, periderm and lenticels, and petiole, blade, and vascular cylinder shape. Our study brings novel information on leaf structure variation in Myrcia sect. Aulomyrcia, delivering much needed data for species and clades circumscription and identification.

A taxonomic account of Myrcia (Myrtaceae) at the sites of the Biological Dynamics of Forest Fragments Project, Amazonas, Brazil

Abstract Myrcia is the sole genus of the Myrciinae, one of the nine subtribes of Myrteae (Myrtaceae). The Amazon forest holds about one-quarter of the Brazilian species of Myrcia, but the genus is still understudied in this whole region. In this context, this study presents a floristic survey of Myrcia in the permanent plots of the Biological Dynamics of Forest Fragments Project (BDFFP), in Amazonas state, Brazil. The genus is represented by 36 species in the study area, comprehending 32% of its total richness in the Brazilian Amazon forest, with 19 of them endemic to this domain. Myrcia neospeciosa is reported as a new occurrence for Amazonas state and M. grandis is recorded for the first time from upland terra firme forests on clayish soils. Myrcia cuspidata, a species with calyptrate flowers, is classified under Myrcia sect. Aulomyrcia, representing the second taxon of the genus with this feature removed from Myrcia sect. Calyptranthes. Finally, morphological aspects of the infra-generic categories of Myrcia are reported more overlapping than previously thought. A map containing the location of the study area, an identification key, descriptions, comments, and figures are provided.

Myrcia longipetiolata (Myrtaceae), a New Species from the Atlantic Forest of Bahia, Brazil

Abstract— Myrcia longipetiolata, a new species of Myrcia, is here described and illustrated. With a phylogenetic hypothesis, we show that this species belongs to Myrcia clade 10, a morphologically recognized and narrowly distributed group of species, which was recently discovered. Myrcia longipetiolata resembles M. unana due to its long leaves, acute or acuminate leaf apex, cuneate leaf base, long petioles, and they share the same area of occurrence. Myrcia longipetiolata differs from M. unana by its larger leaves, larger number of leaf secondary veins, marginal vein more distant from the leaf margin, lanceolate bracteoles, smaller and truncate, rounded, or apiculate calyx lobes with whitish to yellowish trichomes, and smaller floral disc. Besides the phylogenetic placement of M. longipetiolata within the genus, morphological comparisons with related species and comments on its distribution, habitat, and conservation status are also provided.

Tree species delimitation in tropical forest inventories: Perspectives from a taxonomically challenging case study

Forest conservation and management programs rely on precise knowledge of local tree diversity. Distinguishing tree species is a major concern in tropical forest inventories as morphology alone may not be sufficient for species identifications in those highly diverse environments. Therefore, a multi-evidence approach is desirable to avoid subjective interpretations. We tested the contribution of a low-cost integrative protocol for delimiting sympatric species of the taxonomically challenging genus Myrcia (Myrtaceae) in the central Amazon region. We classified specimens into local species by morphotyping them and then validated our hypotheses using two additional sources of evidence: i) near-infrared spectroscopic data, consisting of 1557 absorbance values obtained from dried leaves; and, ii) morphometric data of leaf blade contours, translated into Fourier descriptors and summarized by principal component analysis (PCA), together with four additional leaf characters. The morphotypes were validated using linear discriminant analyses (LDAs) of the raw NIR spectra, stepwise-selected spectral regions, PCA-reduced spectra, as well as the morphometric data. A taxonomic name was assigned to each validated species based on comparisons with herbarium specimens and/or the technical literature. We delimited 38 species of Myrcia, and our hypotheses were well-supported by the LDAs (81–99% accuracy), evidencing that inexpensive tools can be effectively used to discriminate species in large-scale projects, and that integrative approaches are fundamental in that regard. Although vegetative traits were sufficient for species discrimination, fertile samples were crucial for obtaining taxonomic names for them. Thirteen species delimited by us belong to four species complexes, each treated under single species names in the current systematics of the genus. We therefore argue that species delimitations prior to individual identifications are essential for robust species definition in forest plot research because local species do not necessarily match global circumscriptions. This type of approach may greatly alter how local community structures are viewed and consequently modify the results of downstream analyses of ecological studies. We also emphasize that local species delimitations may contribute to the field of taxonomy by identifying potential inconsistencies in global species definitions.

Three new species of Myrcia sect. Myrcia (Myrtaceae) from South America

Three new species of Myrcia are described, illustrated and discussed. Myrcia rionegrensis from the Brazilian Amazon is related to M. clusiifolia from which it differs in having leaves with acute apex and ribbed fruits (vs. rounded apex and smooth fruits in M. clusiifolia); Myrcia microcalyx is similar to Myrcia scytophylla but differs in having pubescent staminal ring and ellipsoid fruits (vs. glabrous staminal ring and globose fruits in M. scytophylla) and Myrcia peruviana is related to M. riverae, but differs in having smaller leaves and flower buds and ellipsoid fruits (vs. globose in M. riverae).

Revisiting Glaziou and the botany of the second Cruls Mission: three new species and 23 accepted species of Myrcia (Myrtaceae) collected from Goiás, Brazil and a detailed description of his “Goyaz” itinerary

Glaziou was one of the most prominent plant collectors in the history of Brazilian botany. His field expeditions during the second Cruls Mission (1894–1895) in the area now recognized as Goiás and Distrito Federal led him to collect 26 of the 32 species of Myrcia he was to name in his botanical career. Glaziou´s itinerary in the second Cruls Mission was reconstructed and mapped, showing he spent 40% of his collecting days in the present Distrito Federal and 60% in Goiás. His List of Species is now considered a suppressed work by the International Code of Nomenclature for the Algae, Fungi and Plants because he did not fulfill the criteria for formal species description. After examining over 300 specimens in Brazilian and European herbaria, we concluded that 23 of his names are synonyms of older, currently accepted names. The remaining three names are new species and are here formally described. This work underlines the importance of revisiting historical collections following recent changes in Myrcia taxonomy, to improve the understanding of species diversity in ecologically heterogeneous areas in large, morphologically complex genera such as Myrcia.

<strong><em>Myrcia</em> (Myrtaceae) in the state of Paraná, Brazil</strong>

Myrtaceae is one of the largest families in number of species within the order Myrtales and one of the richest families in Brazil. Myrcia is the fourth largest genus of Myrtaceae, with approximately 770 species distributed from Central America and the Caribbean to southern South America. In Brazil Myrcia is represented by 397 species, of which 309 are endemic. In this study, we present the taxonomic treatment for all species of Myrcia that occur in Paraná state, Brazil. Analyses of herbarium specimens, online databases, and bibliography were performed. Fifty-three species of Myrcia occur in Paraná, distributed in all vegetation types. Twenty-three names were excluded from previous lists of species or listed as doubtful species. Neither of the recorded species is endemic to Paraná, but this state is the southern and northern limit of distribution of six and two species, respectively. We present an identification key, taxonomic descriptions, figures, maps, and comments on phenology, habitat, and morphology for each species.

Habitat filtering drives the local distribution of congeneric species in a Brazilian white-sand flooded tropical forest.

The investigation of ecological processes that maintain species coexistence is revealing in naturally disturbed environments such as the white‐sand tropical forest, which is subject to periodic flooding that might pose strong habitat filtering to tree species. Congeneric species are a good model to investigate the relative importance of ecological processes that maintain high species diversity because they tend to exploit the same limiting resources and/or have similar tolerance limits to the same environmental conditions due to their close phylogenetic relationship. We aim to find evidence for the action and relative importance of different processes hypothesized to maintain species coexistence in a white‐sand flooded forest in Brazil, taking advantage of data on the detailed spatial structure of populations of congeneric species. Individuals of three Myrcia species were tagged, mapped, and measured for diameter at soil height in a 1‐ha plot. We also sampled seven environmental variables in the plot. We employed several spatial point process models to investigate the possible action of habitat filtering, interspecific competition, and dispersal limitation. Habitat filtering was the most important process driving the local distribution of the three Myrcia species, as they showed associations, albeit of different strength, to environmental variables related to flooding. We did not detect spatial patterns, such as spatial segregation and smaller size of nearby neighbors, that would be consistent with interspecific competition among the three congeneric species and other co‐occurring species. Even though congeners were spatially independent, they responded to differences in the environment. Last, dispersal limitation only led to spatial associations of different size classes for one of the species. Given that white‐sand flooded forests are highly threatened in Brazil, the preservation of their different habitats is of utmost importance to the maintenance of high species richness, as flooding drives the distribution of species in the community.

CLIMATIC NICHE DETERMINES THE GEOGRAPHIC DISTRIBUTION OF MYRTACEAE SPECIES IN BRAZILIAN SUBTROPICAL ATLANTIC FOREST

ABSTRACT The understanding of factors determining species geographic distribution is a fundamental aim of ecology. We investigated the environmental niche for three Myrtaceae species in the Brazilian Subtropical Atlantic Forest (BSAF), part of a global conservation hotspot. Based on a literature review, we selected one representative Myrtaceae species in three important forest types in this region: Evergreen Rain Forest (coastal plains and associated mountains ranges); Araucaria Forest, and Seasonal Deciduous Forest (continental upland areas). Geographical coordinates of their distribution were obtained from the BIEN database. As explanatory variables, we considered altitude, climate, cloud cover, and soil classes. We summarized the environmental space occupied by each pair of species using Principal Components Analysis, determined niche overlaps, and applied statistical tests to verify niche equivalences and similarities. The selected species in Evergreen Rain Forest, Araucaria Forest, and Seasonal Deciduous Forest were Myrcia splendens (Sw.) DC., Myrcia guianensis (Aubl.) DC., and Campomanesia xanthocarpa O.Berg., respectively. C. xanthocarpa showed a more restricted geographic distribution than the two Myrcia species that occur from central America to southern Brazil. Species’ geographic distribution were fundamentally determined by temperature and rainfall regimes. Only C. xanthocarpa and M. guianensis, from uplands forest formations, showed environmental niche equivalence. In conclusion, we found that both species of Myrcia showed high climatic niche amplitudes occurring throughout the climatic gradient, while C. xanthocarpa was more subtropical, distributed mostly in the south and southeast of Brazil.

Myrcia machinazana (Myrtaceae), a new Amazonian species from southern Ecuador

ABSTRACT Myrcia machinazana, a new species from southern Amazonia in Ecuador is described and illustrated; additionally a distribution map is presented and its conservation status and relationships with other species are discussed. This new species is similar to Myrcia gigantifolia, but differs by its reddish to dark-brown indumentum on new growth (vs. new growth glabrous in M. gigantifolia) and dense panicles with compactly arranged flowers and fruits (vs. panicles lax, flowers and fruits loosely arranged in M. gigantifolia). A key to the Ecuadorian species of Myrcia is provided.

A taxonomic account of Myrcia (Myrtaceae) at the sites of the Biological Dynamics of Forest Fragments Project, Amazonas, Brazil

Abstract Myrcia is the sole genus of the Myrciinae, one of the nine subtribes of Myrteae (Myrtaceae). The Amazon forest holds about one-quarter of the Brazilian species of Myrcia, but the genus is still understudied in this whole region. In this context, this study presents a floristic survey of Myrcia in the permanent plots of the Biological Dynamics of Forest Fragments Project (BDFFP), in Amazonas state, Brazil. The genus is represented by 36 species in the study area, comprehending 32% of its total richness in the Brazilian Amazon forest, with 19 of them endemic to this domain. Myrcia neospeciosa is reported as a new occurrence for Amazonas state and M. grandis is recorded for the first time from upland terra firme forests on clayish soils. Myrcia cuspidata, a species with calyptrate flowers, is classified under Myrcia sect. Aulomyrcia, representing the second taxon of the genus with this feature removed from Myrcia sect. Calyptranthes. Finally, morphological aspects of the infra-generic categories of Myrcia are reported more overlapping than previously thought. A map containing the location of the study area, an identification key, descriptions, comments, and figures are provided.

Phenological study of congeneric Myrcia species and Clethra scabra in wetland and drained habitats in a Montane Forest

Although important, phenological studies comparing congeneric species or the same species growing in different habitats are still scarce for the tropics. Herein, we integrate phylogeny, ecology and biometeorology to verify whether the phenophases of congeneric species Myrcia laruotteana and Myrcia amazonica or Clethra scabra differ when their populations inhabit wetland and drained habitats and to determine what abiotic factors affect the vegetative and reproductive phenophases of these species in distinct habitat patches. We collected data on phenological events of 80 trees for 1 year in Itacolomi State Park, Brazil, and related them to abiotic local factors. Contrary to our expectation, the phenophases of the congeneric species did not differ between habitats, but the reproductive phenophases of C. scabra did and was greater in drained soil. Phenophases of C. scabra were affected by the depth of the water table and maximum temperature in the wetland soil. Insolation, precipitation, maximum temperature and relative humidity influenced Myrcia and Clethra in the drained soil. The differences between C. scabra populations suggest that this species is phenotypically plastic and can present distinct phenophases depending on the habitat it inhabits. On the other hand, the congeneric Myrcia species may have similar phenophases in distinct habitats because of their shared similarities during their evolution. This study provides a better understanding of the ecology of these species and their adaptations to different abiotic conditions. Data of this nature are important in a changing world and can inform strategies for adaptive management.

Flavonoids, antioxidant potential and antimicrobial activity of Myrcia rufipila mcvaugh leaves (myrtaceae)

This paper reports the first chemical study of the non-volatile compounds, antioxidant capacity and antimicrobial effect of the methanol extract of the leaves of Myrcia rufipila McVaugh. Samples of the leaves were collected in Maracanã Municipality, Pará, Brazil. The chemical investigation led to the identification of the triterpenoids β- and α-amyrin, the flavonoids 4'-O-galloyldihydromyricetin, myricetin, myricitrin, desmantin-I, myricetin-3-O-(3"-O-galloyl)-α-L-rhamnopyranoside and isovitexin, in addition to gallic acid. The methanol extract showed antioxidant capacity (>90%) against DPPH radical (IC50 356.3 ± 3.1 μg.mL−1) and was active only at high concentrations against the tested microorganisms, including the chloramphenicol resistant E. coli CCMB261 and S. aureus CCMB285 and a nystatin resistant C. parapsilosis CCMB 288. This study shows that M. rufipila, like other Myrcia species, is another source of flavonoids such as desmantin-I and myricitrin which have shown hypoglycemic potential, besides triterpenes and phenolic acids.

Advanced understanding of phylogenetic relationships, morphological evolution and biogeographic history of the mega-diverse plant genus Myrcia and its relatives (Myrtaceae: Myrteae)

Myrcia is the largest exclusively Neotropical genus of the plant family Myrtaceae with c. 770 species. Although several studies have elucidated the relationships within particular sections of the genus, to date no phylogeny has been produced that includes a broad taxonomic and geographic representation. Here we present a phylogenetic hypothesis of Myrcia and close relatives comprising 253 species and based on two nuclear and seven plastid markers. We combine previously available sequence data with 234 new sequences of the genus Myrcia for this study. We use this phylogeny to investigate the evolution of selected morphological traits and to infer the biogeographic history of the genus. Our results yield a highly supported phylogenetic tree where the Myrceugenia group is sister to the Myrcia and Plinia groups. Five Myrcia species previously considered unplaced emerge in a newly circumscribed clade. The monophyly of two Myrcia sections previously considered uncertain, Aulomyrcia and Gomidesia, are confirmed with strong support. Flowers with free calyx lobes, 2-locular ovaries, and anthers with symmetrical thecae are ancestral features of Myrcia. The Myrcia sect. Gomidesia is highly supported and recovered as monophyletic, with asymmetric anthers that retain their curvature after dehiscence as a morphological synapomorphy. The Atlantic Forest is the most likely ancestral area of the genus and most of its internal clades, from where multiple lineages colonized different regions of South and Central America, in particular the Brazilian Cerrado through multiple unidirectional range expansions. The southern Atlantic Forest is the ancestral area for Myrcia sect. Gomidesia, with lineages reaching the northern Atlantic Forest, Cerrado, Yungas, and other savanna vegetation of South America. Our results provide a solid backbone for further evolutionary and taxonomic work and clarify several previously uncertain relationships in this mega-diverse plant group, and shed light on its geographical range evolution.

Host tree bark traits and development of reintroduced Cattleya intermedia (Orchidaceae) plants in Southern Brazil

Abstract The traits of the bark of host trees can influence the distribution and development of epiphytes. Bark samples were suspended in 10 and 20 mL of distilled water for 1, 4 and 24 h, to evaluate pH determination methods. Bark samples of Myrcia brasiliensis, M. glabra and Myrsine coriacea, three host trees of Cattleya intermedia had bark samples collected from the trunk and the crown, for the evaluation of the pH, water retention capacity and thickness. Shoot height (cm) and number of roots of C. intermedia grown on trunk and into the crown of the three species were evaluated. Volume of solvent and suspension time of the bark samples influenced pH values. The pH and thickness of Myrsine coriacea barks were higher when compared to Myrcia species. Shoot height and number of roots of C. intermedia individuals were significantly higher in the crown. The growth parameters of the reintroduced plants were unrelated to pH and bark thickness. The data bring information for the application of further vascular epiphyte studies including new parameters and greater samplings, in order to support proposals of the conservation of endangered species.

Antioxidative, Antiproliferative and Antimicrobial Activities of Phenolic Compounds from Three Myrcia Species.

Myrcia bella Cambess., Myrcia fallax (Rich.) DC. and Myrcia guianensis (Aubl.) DC. (Myrtaceae) are trees found in Brazilian Cerrado. They have been widely used in folk medicine for the treatment of gastrointestinal disorders, hemorrhagic and infectious diseases. Few reports have been found in the literature connecting their phenolic composition and biological activities. In this regard, we have profiled the main phenolic constituents of Myrcia spp. leaves extracts by ESI(−)Q-TOF-MS. The main constituents found were ellagic acid (M. bella), galloyl glucose isomers (M. guianensis) and hexahydroxydiphenic (HHDP) acid derivatives (M. fallax). In addition, quercetin and myricetin derivatives were also found in all Myrcia spp. extracts. The most promising antioxidant activity, measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity, was found for M. fallax extracts (EC50 8.61 ± 0.22 µg·mL−1), being slightly less active than quercetin and gallic acid (EC50 2.96 ± 0.17 and 2.03 ± 0.02 µg·mL−1, respectively). For in vitro antiproliferative activity, M. guianensis showed good activity against leukemia (K562 TGI = 7.45 µg·mL−1). The best antimicrobial activity was observed for M. bella and M. fallax to Escherichia coli (300 and 250 µg·mL−1, respectively). In conclusion, the activities found are closely related to the phenolic composition of these plants.

Brazilian insulin plant as a bifunctional food: Dual high-resolution PTP1B and α-glucosidase inhibition profiling combined with HPLC-HRMS-SPE-NMR for identification of antidiabetic compounds in Myrcia rubella Cambess

Six species of Myrcia, commonly known as 'insulin plants' in Brazil, were assessed for their potential as functional foods. Thus, dual high-resolution α-glucosidase/PTP1B inhibition profiling and HPLC-HRMS-SPE-NMR analysis were used to identify the antidiabetic constituents of the crude ethyl acetate extract of M. rubella Cambess. A total of 31 compounds were identified, including seven α-glucosidase inhibitors with IC50 values between 0.6 and 22.4 μM: 4,5-dicaffeoylquinic acid, isoquercitrin, quercetin-3-O-β-d-glucuronide, kaempferol-3-O-(6″-galloyl)-β-d-glucopyranoside, quercetin-3-O-(6″-malonyl)-glucopyranoside, quercetin-3-O-(6″-(E)-feruloyl)-β-d-glucopyranoside, and quercetin-3-O-(2″-(E)-sinapoyl)-glucopyranoside as well as three strong PTP1B inhibitors with IC50 values between 0.4 and 3.1 μM: kaempferol-3-O-α-l-rhamnoside, astragalin, and arjunolic acid. These results show that M. rubella is a potential bifunctional food for management of type 2 diabetes.