Species Of Melastomataceae Research Articles

Floristic inventory of Melastomataceae of the Iguaçu National Park, Paraná, Brazil

Abstract Melastomataceae is one of the richest families in Brazil, with 1,436 species, 158 occurring in the state of Paraná. Many of the species are pioneers and zoochoric, essential for regeneration and floristic composition of the Atlantic Forest, which is the phytogeographic domain covering the Iguaçu National Park (ParNa Iguaçu). We present the floristic inventory of Melastomataceae of ParNa Iguaçu. Three areas in the park were sampled from May 2019 to March 2020, where two are covered with Seasonal Semideciduous Forest (SSF), and the other in a transition between SSF and Mixed Ombrophilous Forest (MOF). Seventeen species of Melastomataceae in four genera were recorded: Miconia (14 spp.), Acisanthera, Chaetogastra, and Pleroma (with only one species each). Seven species occur in the two vegetation types in ParNa Iguaçu, while six occur only in MOF and four only in SSF. Of the 17 species, six are endemic to Brazil, four of which occur only in the south and southeast regions of the country. This study registers nine new records for the ParNa Iguaçu. Furthermore, the Miconia leaeichleri was collected for the first time in the western region of Paraná, which suggests the necessity for more collection efforts in the western region of the state.

Stamen and pollen heteromorphism linked to the division of labour in Melastomataceae species

The occurrence of stamen heteromorphism within pollen flowers (or heteranthery) has been mostly explained by a division of labour hypothesis, which suggests that some anthers produce pollen for pollination (pollinating anthers) while others are specialized in attracting and rewarding floral visitors (feeding anthers). Despite more than 20.000 species presenting stamen heteromorphism, the morphological and functional traits associated with it have been poorly investigated, especially at the pollen level. Here we evaluated the structural and possible functional roles of stamen and pollen heteromorphism in 16 Melastomataceae species belonging to four tribes. We investigated how a number of traits associated with floral heteromorphisms - anther size, pollen quantity and quality, pollen volume and exine ornamentation - might interact with pollination efficacy and pollinator feeding behaviour. Our results showed morphological differences between anthers and pollen grains that might affect pollinating and feeding functions in the studied species. Pollinating anthers were larger and produced more numerous and more viable pollen grains than feeding anthers. Pollen grain volume between the anther sets was mostly similar in the analysed species, with the exception of three species. Three species of tribe Microlicieae and one from the Marcetieae presented differences in pollen exine ornamentation between pollinating and feeding anthers. Overall, our findings support the division of labour hypothesis for some, but not all, species included in our study. We showed that stamen heteromorphism on the 16 studied species may lead to subtle and specific differences in anthers and pollen morphology which may contribute to their functional role.

Evidence of biotic resistance to exotic plant invasion in degraded Bornean forests

AbstractIntact tropical forests are generally considered to be resistant to invasions by exotic species, although the shrub Clidemia hirta (Melastomataceae) is highly invasive in tropical forests outside its native range. Release from natural enemies (e.g., herbivores and pathogens) contributes to C. hirta invasion success where native melastomes are absent, and here we examine the role of enemies when C. hirta co‐occurs with native Melastomataceae species and associated herbivores and pathogens. We study 21 forest sites within agricultural landscapes in Sabah, Malaysian Borneo, recording herbivory rates in C. hirta and related native Melastoma spp. plants along two 100‐m transects per site that varied in canopy cover. Overall, we found evidence of enemy release; C. hirta had significantly lower herbivory (median occurrence of herbivory per plant = 79% of leaves per plant; median intensity of herbivory per leaf = 6% of leaf area) than native melastomes (93% and 20%, respectively). Herbivory on C. hirta increased when closer to native Melastoma plants with high herbivory damage, and in more shaded locations, and was associated with fewer reproductive organs on C. hirta. This suggests host‐sharing by specialist Melastomataceae herbivores is occurring and may explain why invasion success of C. hirta is lower on Borneo than at locations without related native species present. Thus, natural enemy populations may provide a “biological control service” to suppress invasions of exotic species (i.e., biotic resistance). However, lower herbivory pressures in more open canopy locations may make highly degraded forests within these landscapes more susceptible to invasion.Abstract in Malay is available with online material.

Osbeckia yercaudensis (Melastomataceae) a new species from the Eastern Ghats, India

A new species of Melastomataceae, Osbeckia yercaudensis, endemic to south India, is described from Shevaroy Hills, Tamil Nadu, India. It is morphologically allied to Osbeckia mehrana Giri & Nayar (1986: 429) and Osbeckia wightiana Bentham ex Wight & Arnott (1834:323), an endemic species from south India, but differs in the height of the plant, size of the leaves, 2–3-flowered cymes, oblong to slightly falcate sepals with irregularly emarginate apex and cochleate or U shaped, margins minutely toothed seeds. A detailed description, photographic illustration and comparison table are provided to facilitate identification.

Potential Extracts of Melastomataceae Species from Mount Merapi National Park as Sunprotection Material with Antioxidation and Antiglycation Activities

Ethanol extracts from the leaves of Clidemia hirta (L.) D. Don., and Melastoma affine D. Don., growing in Mount Merapi National Park, Indonesia, had high  antioxidant activity similar to ascorbic acid. Natural substances with high  antioxidant activity potentially inhibit UV-induced skin photoaging. This study  aimed to investigate the sun protection factor (SPF) and antiglycation activity of  C. hirta and M. affine ethanol extracts to identify and obtain candidate  hotoprotective ingredients for sunscreen products. Proximate analysis of extract  simplicial was performed for standardization, and their secondary  metabolites quantified to understand their bioactivities. Flavonoids, alkaloids,  and saponins were quantified using the aluminum chloride, bromocresol green,  and vanillin-sulfuric acid methods, respectively. Phenolic compounds  and tannins were quantified using the Folin-Ciocalteu method. The C. hirta  extract showed a higher SPF value in UV spectrophotometry, and antiglycation  activity through bovine serum albumin-glucose (BSAglucose) method, than the  M. affine extract. An antioxidant assay using the 2,2-diphenyl-1- picrylhydrazyl  (DPPH) radical scavenging method confirmed that the C. hirta and M. affine extracts were more potent and had slightly lower antioxidant activity,  respectively, than ascorbic acid. The high bioactivity of C. hirta extract was likely  due to phenolic compounds, flavonoids, and tannins, because these metabolites  were more abundant in C. hirta extract than in M. affine extract.  These results indicated that the ethanol extract of C. hirta leaves has the  potential to be developed as an ingredient of sunscreen products for skin  photoprotection.&nbsp

Germination and emergence of Miconia sp (Melastomataceae)

Melastomataceae is one of the predominant families of Campos Gerais Paranaenses. However, germination and initial growth of the species in the region have been little studied. To investigate the germination, emergence, and initial growth of five Melastomataceae species in the State Park of Guartelá and in the State Park of Vila Velha, germination bioassays and emergence tests were carried out at 20 ºC, 25 ºC, and 30 ºC in a germination chamber and initial growth wasevaluated in a greenhouse. Miconia cinerascens and Miconia sellowiana had the highest percentage of germination (% G) at 25 ºC and 30 ºC. M. auricoma and M. ligustroides showed no difference in the germination percentage at the three temperatures tested, but germination delayed at 20 °C. M. radii germinated only at 25 ºC and 20 °C. Emergence was slow, both in the greenhouse and in B.O.D, with final germination of M. sellowiana completed by about 70 d in the greenhouse. The temperatures of 25 ºC and 30ºC were found an important factor in the germination of Melastomataceae species in Campos Gerais, with M. Auricoma having initial growth slow.

A new species of Pleroma (Melastomataceae) from the Southern Espinhaço, Minas Gerais, Brazil

Pleroma barbellatum P.J.F.Guim., D.Nunes & I.M.Araújo a new species of Melastomataceae (Melastomateae) from the Espinhaço Range of Minas Gerais State, Brazil, is described and illustrated, and their affinities and diagnostic characters are here discussed. Pleroma barbellatum is closely related to P. formosum, P. martiale, and P. riedelianum. They share a similar habit and leaves that are alike in size and shape. However, they can be distinguished by differences in the trichomes of the branches, leaves and inflorescences, in addition to other characters related to the type of inflorescence and size of the bracteoles. We recommend a conservation status of Endangered for P. barbellatum.

New species of Marcetia and Microlicia (Melastomataceae) endemic to the campo rupestre of Chapada Diamantina, Bahia, Brazil

During recent field expeditions to the Chapada Diamantina (Bahia, Brazil), nine new endemic species of Melastomataceae were collected and are here described and illustrated: Marcetia auricularia, Marcetia santosiae, Marcetia unguiculata, Microlicia ascendens, Microlicia barbata, Microlicia daneui, Microlicia piatensis, Microlicia prostrata, and Microlicia tetramera. We provide photos of living and dry specimens, geographic distribution maps, notes on habitat and phenology for each species, and recommended conservation assessments. Marcetia auricularia, Marcetia unguiculata and Microlicia daneui were collected within a full protection conservation unit, the Chapada Diamantina National Park. Populations of Marcetia santosiae, Microlicia ascendens, Microlicia barbata, Microlicia prostrata, and Microlicia tetramera grow in a sustainable use conservation unit, the Serra do Barbado APA; no protection is afforded to Microlicia piatensis, as it occurs outside all conservation units in the Chapada Diamantina.

What is the role of stamen appendages in the buzz-pollinated Huberia insignis (Melastomataceae)?

In most species of Melastomataceae pollen is the only reward for pollinators. Pollen is locked within poricidal anthers and is only legitimately removed by bees that specifically buzz the anthers. Stamen appendages in many species of plants are morphological adaptations of the androecium for pollination, and are evident in several species of Melastomataceae. In an experimental study, anthers with large, coiled appendages released more pollen during artificial buzzing in flowers of the genus Huberia than anthers without appendages. Other aspects of reproductive biology and pollination ecology in Huberia are poorly known, including the relationship between size and shape of widely varying stamen appendages with pollen release. In the Brazilian Atlantic Forest, we studied the breeding system and pollinator assemblage of the endemic Huberia insignis, and we experimentally tested how stamen appendages are associated with pollination. With hand-pollination experiments, morphoanatomical analysis, observations of the pollinator assemblage, using flowers with and without stamen appendages, we tested pollinator preferences and the effect of appendage presence on pollen removal rates. Huberia insignis is self-compatible and requires pollinators, and bees that buzz-pollinate are the only pollinators, typically two species of Bombus (ca. 80% of visits). The presence of stamen appendages of H. insignis had no effects on attracting pollinators and pollen removal. Anthers and stamen appendages have neither secretory structures nor specialized biomechanical tissues. We conclude that stamen appendages play no role in the pollination of H. insignis. We suggest that these typically small and inconspicuous stamen appendages are vestigial.

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.

Observations on the Population Genetic Structure of the Leaf Galling Nematode, Ditylenchus gallaeformans.

Ditylenchus gallaeformans is a plant parasitic nematode that induces galls on aboveground parts of Melastomataceae plants. It differs from most gall-inducing nematodes in that it is not an endoparasite and has been considered as a possible biological control agent against invasive species of Miconia. Little is known about D. gallaeformans biology, genetic differences among populations, and host preferences. This study examined the genetic differences among D. gallaeformans populations from different locations and host species and the phylogenetic relationships among them. Nematodes were collected from galls in plants from Costa Rica, Dominica, and Trinidad. The Cytochrome c oxidase 1 (cox1) region was sequenced from a total of 33 individual nematodes isolated from 33 different plant individuals, representing 21 species of Melastomataceae. Phylogenetic reconstructions, haplotype networks, and analysis of molecular variance showed that the species is monophyletic and has three major clades, which were mostly consistent with geographic location but not with host species. The first clade was composed by two subclades, one with individuals from Costa Rica and one with individuals from Dominica. The second and third clades comprised nematodes only from Trinidad. Overall, there is no evidence of host-species specialization in D. gallaeformans. Biocontrol efforts using the nematode against invasive Miconia could focus on geographical location matching but likely will not need to match host 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.

Sonerila lundinii, a new species of Melastomataceae from southern Western Ghats with notes on Sonerila pedunculosa, a less known taxon from Sri Lanka

Founded in 1991 and published by the Indian Association for Angiosperm Taxonomy (IAAT), Rheedea is an international peer-reviewed journal with four online and two print issues per year. The online issues will be published in March, June, September and December while the printed issues will be published in June and December.

Distinct pollen release dynamics between stamens generate division of labour in pollen flowers of two Pleroma species (Melastomataceae)

Flowers that provide only pollen to pollinators should maximize pollen release for reproduction while minimizing pollen loss through consumption by bees. In flowers that are polymorphic for stamen type, the number of pollen grains produced as well as stamen morphology likely influences pollen release dynamics and favor the division of labor between stamens with different functions. However, few studies have evaluated such predictions. In this study, we tested the “division of labor hypothesis” considering not only the stamen morphology of pollen flowers but also their pollen release dynamics. Stamen morphology as well as the amount and viability of pollen were characterized in two Melastomataceae species, Pleroma granulosum and Pleroma raddianum. Using artificial vibrations, we estimated pollen release dynamics throughout anthesis in the anthers of short and long stamens from flowers of both species. P. granulosum flowers presented low heteranthery (i.e., anthers differed by only about 1 mm in length) and short stamens produced fewer pollen grains in both species. We also found similarly high viability of pollen from all anthers of both species. Although pollen grain release increased in all anthers over the flower´s lifespan, their dynamics were different between the two stamen sets in both species. Anthers of shorter stamens tended to release fewer and proportionally lower quantities of pollen grains at each time interval than anthers of longer stamens. Our study suggests that the number of pollen grains produced, as well as stamen morphology (beyond anther size) may control pollen release dynamics, leading to a division of labor between stamens in these pollen flowers.

The predictive power of pollination syndromes: Passerine pollination in heterantherous Meriania macrophylla (Benth.) Triana (Melastomataceae).

The cloud forest species Meriania macrophylla (Benth.) Triana has pseudocampanulate flowers with bulbous stamen appendages, typical for the passerine pollination syndrome found in the Melastomataceae tribe Merianieae. The species is further characterized by strong stamen dimorphism (heteranthery), a condition otherwise associated with pollen‐rewarding bee‐pollinated species (both in Melastomataceae and beyond). In passerine‐pollinated Merianieae, however, flowers usually only show weak stamen dimorphism. Here, we conducted field and laboratory investigations to determine the pollinators of M. macrophylla and assess the potential role of strong heteranthery in this species. Our field observations in Costa Rica confirmed syndrome predictions and indeed proved pollination by passerine birds in M. macrophylla. The large bulbous set of stamens functions as a food‐body reward to the pollinating birds, and as trigger for pollen release (bellows mechanism) as typical for the passerine syndrome in Merianieae. In contrast to other passerine‐pollinated Merianieae, the second set of stamens has seemingly lost its rewarding and pollination function, however. Our results demonstrate the utility of the pollination syndrome concept even in light of potentially misleading traits such as strong heteranthery.

<p><strong><em>Miconia</em></strong><strong> <em>lorenaensis</em> (Melastomataceae), a new species from Colombian Andes</strong></p>

A new species of Melastomataceae from the Andes of Colombia is described and illustrated. Miconia lorenaensis is part of Miconia sect. Amblyarrhena, and it differs from other species in this group by the combination of branches, petioles and leaves covered by scattered short dendritic trichomes, 7-nerved peltate leaves, acuminate or cuspidate apex with a circinate-thickened tip and flowers with completely inferior, 3-locular ovary. Comments about its distribution, habitat, phenology and taxonomic affinities are provided.

<strong><em>Tigridiopalma longmenensis</em> (Melastomataceae), a new species from Guangdong, China</strong>

Tigridiopalma longmenensis, a new species from Guangdong, China, is described. This species differs from its ally, T. magnifica, by the polychasium consisting of scorpioid cymes, hypanthium with carinas on angles, and longer stamens with a conspicuously white or pink spur at the connective base of anther. A diagnosis and a distribution map of the two species are also provided. The complete chloroplast genome of T. longmenensis was reported here. Phylogenetic analyses based on complete chloroplast genomes from T. longmenensis and other 15 Melastomataceae species indicated that T. longmenensis is sister to T. magnifica. The discovery of T. longmenensis terminates Tigridiopalma as a monotypic genus.

Phenological responses to climate change based on a hundred years of herbarium collections of tropical Melastomataceae.

Changes in phenological events have been vastly documented in face of recent global climate change. These studies are concentrated on temperate plants, and the responses of tropical species are still little understood, likely due to the lack of long-term phenological records in the tropics. In this case, the use of herbarium specimens to gather phenological data over long periods and wide geographic areas has emerged as a powerful tool. Here, we used four Melastomataceae species endemic to the Brazilian Atlantic Forest to evaluate phenological patterns and alterations as responses to recent climate changes. Phenological data were gathered from Reflora Virtual Herbarium specimens collected between 1920 and 2018, and analyzed with circular statistics applied to the intervals 1920–1979, 1980–1999, and 2000–2018. The effects of temperature range, average temperature, precipitation, and photoperiod on flowering and fruiting of each species were tested using multiple linear regressions. Through circular statistics, we detected changes, mostly delays, in the flowering of Miconia quinquedentata, Pleroma clavatum and P. trichopodum, and in the fruiting of M. acutiflora, P. clavatum and P. trichopodum. We also found that flowering and fruiting occurrence were related to local climatic conditions from months prior to the collections. We found marked phenological variations over the decades and also that these variations are associated to global climate change, adding up to the large body of evidence from higher latitudes. Our results also support herbarium collections as an important source for long-term tropical phenological studies. The lack of consistent patterns of responses among the four species (e.g. fruiting delayed two months in P. clavatum and advanced one month in M. acutiflora) suggests that climate change has unequal effects across tropical forests. This highlights the urgent need for further research to understand and forecast the ecological implications of these changes in global ecosystems processes.

Tigridiopalma exalata, a new and endangered species of Melastomataceae from China.

A new species of the genus Tigridiopalma, formerly considered monotypic, is here described as T. exalata and illustrated based on molecular and morphological evidence. It is morphologically similar to T. magnifica in having a short stem, huge basal leaves, scorpioid cymes, and 5-merous flowers, but differs in having ribbed and pale yellow puberulent petioles, purple petals with a small white apical patch, connectives of longer stamens with a distinct dorsal short spur at their base, and wingless capsules. Due to the restricted distribution, small populations and horticultural potential of this new species, it should be categorized as an Endangered species (EN).

Memecylon viswanathanii, a new species of Melastomataceae from Kalakkad-Mundanthurai Tiger Reserve (KMTR), India

Memecylon viswanathanii R.Rajesh, P.Sakthidhasan & C.Rajasekar, a new species of Melastomataceae, is described and illustrated from the Kalakkad-Mundanthurai Tiger Reserve (KMTR) in the southern Western Ghats of India. M. viswanathanii is close to M. parvifolium Thwaites and M. varians Thwaites but differs by several vegetative and floral characters. The species is assessed here as Critically endangered as per IUCN Red List.