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Andrographis saxatilis (Acanthaceae), a new species, is described and illustrated from the rocky plateau of the Owk dam area, Andhra Pradesh. It is a perennial, woody‐root‐stocked undershrub. Unique characteristics of this species include hispid hairs, obovate, elliptic‐oblong and oblanceolate leaves, lanceolate glandular hairy sepals, and sterile bract and calyx towards base of rachis. Andrographis saxatilis is closely allied to A. glandulosa Nees by its perennial habit, woody rootstock in rocky crevices, glaucous green leaves, hairy stem, and glandular and attenuate hairy calyx and corolla. However, it is distinguished from the later by its hispid texture (versus densely pubescent in A. glandulosa), obovate, elliptic‐oblong, and oblanceolate leaves (versus ovate‐oblong), obtusely 4‐angled stem (versus acutely 4‐angled), hispid and glandular hairy sepals (versus villous), boat‐shaped upper lip of corolla (versus ligulate), and pubescent fruit (versus glabrous at base and glandular hairy towards the tip in A. glandulosa). The IUCN threat status of A. saxatilis is assessed as ‘Critically Endangered' (CR). [ABSTRACT FROM AUTHOR]

Cleistogamy is characterized by the presence of flowers that are permanently closed, yet they still produce fruits and seeds through autonomous self‐pollination. Populations with cleistogamous flowers can also have flowers that open, called chasmogamous, which promote cross‐pollination and genetic variability. Acanthaceae is among the families with the highest frequency of cleistogamy, observed mainly in Ruellia. This study aimed to assess cleistogamy in Ruellia blechum for the first time. In a population in Central Brazil, we analysed the production of cleistogamous and chasmogamous flowers, their fruiting, differences in flower bud size, self‐pollination in cleistogamous flowers and visitors in chasmogamous flowers. Of the flower buds observed, 35.29% remained closed (cleistogamous flowers), with 31.25% of them forming fruit. In contrast, 60.24% of the flowers that opened (chasmogamous) developed fruit. The length of cleistogamous flowers was shorter than that of chasmogamous floral buds in pre‐anthesis. On average, 24.45 pollen grains were self‐deposited on the stigma of a cleistogamous flower. The chasmogamous flowers were visited mainly by small bees. This study is the first to confirm the presence of cleistogamous flowers in R. blechum. However, their co‐occurrence with chasmogamous flowers suggests a fitness advantage for maintaining a mixed mating strategy. [ABSTRACT FROM AUTHOR]

The subtropical rainforest shrub Graptophyllum reticulatum (Acanthaceae) occurs in only a few populations within a 20‐kilometer range in the Sunshine Coast, south‐east Queensland, Australia. This endangered plant has been subject to habitat degradation and loss, mostly due to land clearing and urbanization. In the past decades, conservation measures such as land protection and translocation have been put in place to protect the species' wild populations. The aim of the study was to analyze the viability of the species' populations in the long term while assessing the effectiveness of land protection and translocation. Demographic data was collected every decade since 2000; for this study, we resurveyed all known populations including a translocated population and two recently discovered populations. We found that the average number of plants per population has doubled since 2000, except in one population that underwent land clearing. However, after being reduced by 70%, plant abundance in this population has been increasing, giving evidence of natural post‐clearing recovery. We developed population growth models for population viability analysis in best, average, and worst‐case scenarios to predict the species' viability over the next 100 years. All populations are expected to grow in the next 100 years, except in the worst‐case scenario in which removing land protection from the model led to an 80% decline in the total number of plants within 100 years, highlighting the importance of land protection for species' conservation. Overall, if current conservation efforts are maintained, this endangered species is likely to persist for the next 100 years. [ABSTRACT FROM AUTHOR]

The taxonomic status of Asystasia gangetica var. krishnae has been evaluated and compared with the closely resembling taxon A. intrusa (synonyms: A. gangetica subsp. micrantha and A. micrantha). The trait that differentiates the two taxa, as per reports, is the occurrence of vertical violet‐black bands on the sides of anthers in the former taxon. The authors explain that var. krishnae could be the first report of A. intrusa for the country and suggest the possibility of neglecting the violet black bands in the previous descriptions of A. intrusa. [ABSTRACT FROM AUTHOR]

Apart from its role in plant taxonomy, the understanding of pollen morphology is considered an essential interdisciplinary tool in diverse applied fields, including plant systematics, melissopalynology, aeropalynology, forensic palynology, paleopalynology, and copropalynology. In palynotaxonomy, it is frequently employed to classify and validate natural groups across a range of hierarchical levels, from higher categories down to the infrageneric level. The subfamily Acanthoideae, within the Acanthaceae family, consists of a diverse group of flowering plants that are distributed globally. The present study attempted a comprehensive analysis of the pollen morphology, employing both light microscopy (LM) and scanning electron microscopy (SEM), for a total of 13 Acanthoideae species from the Shivalik Foothills in Rajaji National Park (located in the northern Indian state of Uttarakhand, Western Himalaya). The findings indicated that the Acanthoideae is characterized by eurypalynous features, and the studied species exhibited pollen grains that were monads, radially symmetrical, and varied in size from small to large. The pollen grains were predominantly tricolporate or heteroaperturate, with porate occurrences being rare. The significant variation in exine sculpturing, including reticulate, coarsely reticulate, and bireticulate patterns, holds substantial taxonomic significance. The detailed presentation encompasses pollen morphological characters described with LM and SEM micrographs, along with a species‐level identification key. Research Highlights: This article provides a thorough analysis of the pollen morphology of Acanthoideae taxa using both light microscopy and scanning electron microscopy, covering 13 species across 10 genera and revealing a broad spectrum of pollen characteristics, including size, shape, aperture type, and exine sculpturing.The microscopic investigation of these Acanthoideae species not only enhances our understanding of their pollen morphology but also aids in species identification through the development of a pollen‐based key. [ABSTRACT FROM AUTHOR]

Andrographis theniensis Karupp. and Bharath (Acanthaceae), a new species from the Megamalai Wildlife Sanctuary of the southern Western Ghats, is described and illustrated here. A detailed description, illustration, color photographs, a table of comparisons to allied species, an identification key and IUCN conservation status are provided here for easy recognition of the new species. [ABSTRACT FROM AUTHOR]

Premise: What maintains mixed mating is an evolutionary enigma. Cleistogamy—the production of both potentially outcrossing chasmogamous and obligately selfing cleistogamous flowers on the same individual plant—is an excellent system to study the costs of selfing. Inbreeding depression can prevent the evolution of greater selfing within populations, and heterosis in crosses between populations may further tip the balance in favor of outcrossing. Few empirical estimates of inbreeding depression and heterosis in the same system exist for cleistogamous species. Methods: We investigate the potential costs of selfing by quantifying inbreeding depression and heterosis in three populations of the cleistogamous perennial Ruellia humilis Nutt (Acanthaceae). We performed three types of hand‐pollinations—self, outcross‐within, and outcross‐between populations—and measured seed number, germination, total flower production, and estimated cumulative fitness for the resulting progeny in a greenhouse experiment. Results: We found moderate inbreeding depression for cumulative fitness (<30%) in two populations, but outbreeding depression for crosses within a third population (–26%). For between‐population crosses, there was weak to modest heterosis (11–47%) in two of the population combinations, but modest to strong outbreeding depression (–21 to –71%) in the other four combinations. Conclusions: Neither inbreeding depression nor heterosis was of sufficient magnitude to explain the continued production of chasmogamous flowers given the relative energetic advantage of cleistogamous flowers previously estimated for these populations. Outbreeding depression either within or between populations makes the maintenance of chasmogamous flowers even harder to explain. More information is needed on the genetic basis of cleistogamy to resolve this conundrum. [ABSTRACT FROM AUTHOR]

The three remaining untypified Linnaean binomials in the genus Barleria, described based on material from India, are lectotypified: B. buxifolia, B. hystrix and B. longifolia. The confusion over the taxonomic identity of B. buxifolia is discussed and the need for an epitype indicated. [ABSTRACT FROM AUTHOR]

Intralaminar galls of Meunieriella result from ground tissue proliferation in leaves of Avicennia schaueriana, a typical halophytic mangrove. We tested if the preferred sites of gall induction were the midribs and secondary veins (SV) at the basal leaf portion, where the galls were expected to be largest; and if the vascular system in galls and adjacent regions was altered to favour water supply in galls, thus increasing their growth.Gall induction sites and gall sizes were quantified according to leaf portions and regions. Anatomical and histometric analyses in vascular and ground tissues of galls and adjacent regions were compared to equivalent regions of non‐galled leaves.The galls were largest at basal sites on leaves, the midrib and SV. More galls occurred on the apical portion of the leaf, and on the leaf blade and secondary vein regions. Changes in shape and vascular system area, number and diameter of vessel elements were detected in both galls and adjacent regions. Fewer and smaller‐sized vessel elements were observed in regions proximal to the galls and inside them.Gall size is not related with preferred induction sites, which could be explained by factors such as thermal balance. Alterations in the vascular system indicate reduced hydraulic conductivity in the xylem in the proximal region and inside galls, leading to water leakage to gall parenchyma cells. This compensatory mechanism explains the expansion and proliferation of water storage and spongy parenchyma cells in the galls, explaining the higher growth in more vascularized regions. [ABSTRACT FROM AUTHOR]

Premise: In the absence of hawkmoth pollinators, chasmogamous (CH) flowers of Ruellia humilis self‐pollinate by two secondary mechanisms. Other floral visitors might exert selection on CH floral traits to restore outcrossing, but at the same time preferential predation of CH seeds generates selection to increase the allocation of resources to cleistogamous (CL) flowers. Methods: To assess the potential for an evolutionary response to these competing selection pressures, we estimated additive genetic variances (σA2 ${\sigma }_{{\rm{A}}}^{2}$) and covariances for 14 reproductive traits and three fitness components in a Missouri population lacking hawkmoth pollinators. Results: We found significant σA2 ${\sigma }_{{\rm{A}}}^{2}$ for all 11 floral traits and two measures of resource allocation to CL flowers, indicating the potential for a short‐term response to selection on most reproductive traits. Selection generated by seed predators is predicted to increase the percentage of CL flowers by 0.24% per generation, and mean stigma–anther separation is predicted to decrease as a correlated response, increasing the fraction of plants that engage in prior selfing. However, the initial response to this selection is opposed by strong directional dominance. Conclusions: The predicted evolutionary decrease in the number of CH flowers available for potential outcrossing, combined with the apparent preclusion of potential diurnal pollinators by the pollen‐harvesting activities of sweat bees, suggest that 100% cleistogamy is the likely outcome of evolution in the absence of hawkmoths. However, rare mutations with large effects, such as delaying budbreak until after sunrise, could provide pathways for the restoration of outcrossing that are not reachable by gradual quantitative‐genetic evolution. [ABSTRACT FROM AUTHOR]

Andrographis paniculata is an annual medicinal herb from the family Acanthaceae. Andrographolide is generally considered an essential bioactive component of plant A. paniculata. Since ancient times, it has been widely recognized for its therapeutic qualities and has attracted the scientific and medical communities' attention. This review summarizes the molecular, clinical, and in vitro research of compound andrographolide and its mechanism of action. Andrographolide, when combined with other enhancing agents, offers a wide variety of health benefits. The therapeutic potential of andrographolide has been exemplified and exhibited by directly regulating genes and indirectly interacting with small molecules and different enzymes. This review compiles and consolidates the pharmacological action of andrographolide and its analogs and deciphers the gaps that have hindered its use in medicinal research. [ABSTRACT FROM AUTHOR]

Lepidagathis mahakassapae sp. nov., a monocarpic and endemic species of Acanthaceae, is described from Western Maharashtra, India. The new species is allied to L. sabui from Konkan, Maharashtra, but differs by having oblanceolate acuminate leaves, pubescent terminal elongated spikes, large floral but small sterile bracts and lanceolate broader segment of the bracteole. The stems of L. mahakassapae grows up to 250 cm in length while a few other prostrate species grows up to this length. Illustrations and colour photographs are provided for ease of identification. [ABSTRACT FROM AUTHOR]

Besides its importance as an ornamental plant, Justicia betonica L. is also used as a medicinal plant for the treatment of several human disorders. However, the population size and abundance of the plant species are very low in Indian states, including West Bengal. The breeding system and pollination ecology of J. betonica are still unclear. Therefore, some reproductive aspects were investigated in order to provide important information for the sustainability of the species. The flowering duration spanned from December to May, with its peak in February–March. Flower opening time was much earlier (5.00–8.00 a.m.) on a hot day (in April–May) than on a cold day (10.00 a.m.–12.00 p.m. in December–January). The time of anther dehiscence coincided with the flower opening time; however, the stigma became receptive later. The plant species is self‐compatible but dependent on pollinators for fruit and seed sets. Members of different insect groups like ants, bees, butterflies, flies, moths and wasps visit the flowers. Among them, Allorhynchium metallicum and Halictus acrocephalus are the primary pollinators (based on the "relative pollinator service"). The plant species showed a significant pollination deficit (coefficient of pollination deficit [D] = 0.32) in the open condition. Larvae of the florivorous moth Gatesclarkeana erotias significantly reduced reproductive success by eating their floral parts, ovules and immature seeds. In conclusion, combining the pollination deficit and the feeding activity of phytophagous insects (moth larvae) may reduce the reproductive fitness of J. betonica in the study regions. [ABSTRACT FROM AUTHOR]

Herbivory is considered an important biotic interaction in mangroves. Nevertheless, detailed information on specific plant-herbivore interactions that might have considerable influence in ecological and evolutionary processes is still very poor and fragmented. Herbivory damage was quantified during December 2015 in seedlings and trees in monospecific stands of Avicennia germinans in Laguna Madre of Tamaulipas, Mexico. The use of this mangrove species as a larval host is well documented; however, this is the first report for Junonia litoralis. These lepidopteran larvae consumed, on average, 10.2% of the leaf area; but herbivory was higher on seedlings (mean 15%) than on trees (mean 2.3%). These values are comparable to estimations of 10% mean herbivory damage in other field studies. This indicates that herbivores cause greater damage in seedlings than in trees. Herbivore activity by J. litoralis only occurred in A. germinans and did not affect associated herbs or shrubs of other species. The close interaction between J. litoralis and A. germinans may have profound implications for ecological and evolutionary processes of mangroves and enables a better understanding of ecosystem function and its conservation. Further studies are needed to investigate such interactions and their implications including long-term monitoring of interstitial salinity and leaf chemistry at different stages of growth and maturity of the host species. [ABSTRACT FROM AUTHOR]

Haplanthodes (Acanthaceae) is an Indian endemic genus with four species. It is closely related to Andrographis which is also mainly distributed in India. Haplanthodes differs from Andrographis by the presence of cladodes in the inflorescences, subactinomorphic flowers, stamens included within the corolla tube, pouched stamens and oblate pollen grains. To understand the phylogenetic relationship of Haplanthodes, Andrographis and Haplanthus, which are putatively closely related taxa, we used four plastid markers, matK, rbcL, psbA‐trnH and trnGRto construct a molecular phylogeny. Our results established the monophyly of Haplanthodes and revealed a sister relationship to Andrographis and Haplanthus. Further, to understand the historical biogeography of the genus, we inferred the divergence time and performed an ancestral area reconstruction. Our analyses suggest that Haplanthodes evolved during Late Miocene 5.85 Ma (95%HPD: 2.18–10.34 Ma) in peninsular India where it might have shared a common ancestor with Andrographis. To understand character evolution, the ancestral states of important morphological characters were inferred and discussed based on the equal rate model. The generic status of Haplanthus was not resolved due to incomplete sampling. [ABSTRACT FROM AUTHOR]

As the first step towards solving the taxonomic problems in the genus Sanchezia (Acanthaceae), neglected for more than 50 years, new synonymies are proposed in this study. Based on an extensive morphological revision, 11 names are synonymized, as follows: S. stenomacra under S. aurea; S. cyathibractea under S. macrocnemis; S. bicolor, S. flava, S. megalia and S. speciosa under S. oblonga; S. capitata and S. stenantha under S. ovata; S. lutea under S. parviflora; S. skutchii under S. putumayensis; and S. arborea and S. decora under S. scandens. With these nomenclatural changes, the number of accepted names within Sanchezia decreases from 55 to 44. Lectotypes are designated for Ancylogyne macrocnemis and S. ovata. Diagnostic characters are provided to identify the treated species, and their taxonomic problems are discussed, highlighting the need for a taxonomic revision of the genus. [ABSTRACT FROM AUTHOR]

Acanthaceae are among the most taxonomically diverse, geographically widespread, and morphologically and ecologically variable lineages of flowering plants. Most modern workers have estimated more than 4000 species and potentially more than 5000 species worldwide, thus placing Acanthaceae among the 12 or so most diverse families of angiosperms. This diversity is marked by exceptional morphological variation, particularly with respect to floral forms, growth forms, and pollen types. The present work represents a synthesis of knowledge generated over the past two decades on the taxonomy and systematics of this complex plant family. We place all 191 accepted genera within a revised classification of the family. Dichotomous keys (nine in total) to recognize the major lineages of Acanthaceae are presented together with geographically partitioned keys to all genera, covering (a) Africa, Madagascar, the Mediterranean region, and Arabia; (b) Asia and Australasia; and (c) the Americas. Finally, we validate several new tribes, subtribes, and genera, and provide new combinations for species where generic delimitation has changed. Our hope is that the present contribution serves to benefit future research on the systematics of Acanthaceae and provides a foundation upon which future classification efforts can be built. [ABSTRACT FROM AUTHOR]

During preparation of a revision of the genus Eranthemum (Acanthaceae), it became evident that nine specimens from eastern and south‐eastern floristic regions of Thailand and southern Laos represent a new species which is herein described, illustrated and given the name E. decumbens. The new species has affinities to E. strictum and E. roseum. A key to the species of Eranthemum occurring in Thailand is provided, together with ecological data, distribution map and conservation status. [ABSTRACT FROM AUTHOR]

The diagnostic value of leaf shape for mangrove species Avicennia germinans and A. schaueriana was examined in four areas within the Rio Parnaíba delta, Maranhão, Brazil. Elliptic Fourier analysis of 627 leaves, followed by principal component analysis, provided shape and size data; the first seven principal component shape variables expressed 99.2% total variation. Discrimination between twelve combinations of species, location and disturbance levels was studied using k‐nearest‐neighbour classification. The species differed significantly in leaf shape but determination was reliable only in the tallest undisturbed forest (germinans narrowly elliptic or ovate, base acute, apex acute to acuminate; schaueriana broadly obovate, base attenuate, apex rounded). Symmetric variables (PC1 and PC3, 84.5% total variation) showed strongest differences. Predominant variation between species was in relative width and base shape (PC1), and within species in ovateness (PC3) between conserved and regenerating areas. Leaves were significantly smaller in A. schaueriana. Vernacular taxa siriba branca and siriba preta were inconsistent with taxonomic species but often significantly different in leaf shape. Avicennia germinans varied more under different geographical and ecological conditions. Shape‐size correlation needs further allometric study. Species delimitation needs morphometric study of a broader character range. Vernacular taxa recognition should be studied with ethnobiological techniques. [ABSTRACT FROM AUTHOR]

Reproductive character displacement is a pattern whereby sympatric lineages diverge more in reproductive character morphology than allopatric lineages. This pattern has been observed in many plant species, but comparably few have sought to disentangle underlying mechanisms. Here, in a diverse lineage of Neotropical plants (Ruellia; Acanthaceae), we present evidence of reproductive character displacement in a macroevolutionary framework (i.e., among species) and document mechanistic underpinnings. In a series of interspecific hand pollinations in a controlled glasshouse environment, we found that crosses between species that differed more in overall flower size, particularly in style length, were significantly less likely to produce viable seeds. Further, species pairs that failed to set seed were more likely to have sympatric distributions in nature. Competition for pollinators and reinforcement to avoid costly interspecific mating could both result in these patterns and are not mutually exclusive processes. Our results add to growing evidence that reproductive character displacement contributes to exceptional floral diversity of angiosperms. [ABSTRACT FROM AUTHOR]

A new species of Strobilanthes collected from Pushpagiri Wildlife Sanctuary, Karnataka, India is described here as S. pushpagiriensis. It is closely allied to S. anamallaica and S. ciliata in having two distinct small leafy bracts at the middle of the peduncle, but differs from them in having dense grayish‐white hairs throughout, linear‐lanceolate leaves with 9–11 pairs of secondary veins, 2–3 spikes per peduncle and linear‐lanceolate densely glandular hairy bracts. Detailed description, distribution, conservation status, illustration and photographs are provided. [ABSTRACT FROM AUTHOR]

Summary: Strobilanthes hamiltoniana is described and illustrated. It is named after Francis Buchanan‐Hamilton who discovered it in Assam in 1808. Over the years, it has been known under different names which reflect both taxonomic changes and the variability of the species. Wild forms from the Himalayan region are predominantly white‐ or pale lilac‐flowered, whereas cultivated and naturalized plants found elsewhere are pink‐flowered and nearly always sterile. Propagation is, therefore, by cuttings. It is widely cultivated in places with a tropical climate or where tropical conditions can be replicated. It has become widely naturalized and even invasive on some oceanic islands. [ABSTRACT FROM AUTHOR]

A recent exploration of the Sagaing Region, Myanmar resulted in the re‐collection of Ruellia bella Craib, a long lost species previously known to be endemic to Thailand that was first described by Craib over 100 years ago. This study reports the first record of the species in Myanmar and presents an amended English description based on our newly collected material, colour photographs to aid accurate identification, and its proposed conservation status. An artificial key to the Ruellia species of Myanmar is provided below. [ABSTRACT FROM AUTHOR]

New Findings: What is the central question of this study?Can Justicia flava leaf extract (JF) inhibit human myometrial contractility as was previously shown in mouse myometrium?What is the main finding and its importance?JF abolished human myometrial contractions and therefore presents as a lead plant in drug discovery studies involving drugs for preterm birth. In the search for new potent therapies for preterm labour, Justicia flava leaf extract (JF) was previously shown to potently inhibit uterine contractility in both pregnant and non‐pregnant mouse uterus. This study took the investigation a step further and investigated the activity of JF on pregnant human myometrial contractility. JF potently inhibited human myometrial contractility in a concentration‐dependent manner. This pilot study provides evidence that JF should be further investigated as a lead plant in the drug discovery of new uterine relaxants. [ABSTRACT FROM AUTHOR]

Premise: The multiple exogenous pathways by which light availability affects plant reproduction (e.g., via influence on attraction of mutualists and antagonists) remain surprisingly understudied. The light environment experienced by a parent can also have transgenerational effects on offspring via these same pathways. Methods: We evaluated (a) the influence of light availability on floral traits in Odontonema cuspidatum, (b) the relative importance of the pathways by which light influences nectar robbery and reproductive output, and (c) the role of parental light environment in mediating these relationships. We conducted a reciprocal translocation experiment using clonally propagated ramets and field surveys of naturally occurring plants. Results: Light availability influenced multiple floral traits, including flower number and nectar volume, which in turn influenced nectar robbery. But nectar robbery was also directly influenced by light availability, due to light effects on nectar robber foraging behavior or neighborhood floral context. Parental light environment mediated the link between light availability and nectar robber attraction, suggesting local adaptation to low‐light environments in floral visitor attraction. However, we found no transgenerational effect on reproduction. Conclusions: Our findings demonstrate that exogenous pathways by which light influences plants (particularly through effects on floral antagonists) can complicate the positive relationship between light availability and plant reproduction. Our results are among the first to document effects of light on floral antagonists and clonal transgenerational effects on flower visitor attraction traits. [ABSTRACT FROM AUTHOR]

In this study, foliar anatomy and pollen morphology of 10 species of Acanthaceae has been investigated using light and scanning electron microscopy. The study was aimed to highlight the role of microscopy in microteaching at community for proper characterization of plants using palyno‐anatomical characters including pollen type, exine sculpturing, shape of epidermal cells, pattern of anticlinal wall, type and size of stomata, and trichome. Most of the species have polygonal cell shapes but some species have irregular, tetragonal, and pentagonal shape of epidermal cells. The largest epidermal cell length on adaxial and abaxial surface were observed in Asystasia gangetica 66.95 and 87.40 μm whereas least was observed on adaxial surface in Justicia adhatoda 36.9 μm and on abaxial surface in Barleria cristata 35.65 μm. In anatomy, species have diacytic type of stomata, whereas stomata of paracytic type observed in two species, while in A. gangetica cyclocytic type of stomata are present. Quantitively on abaxial surface, largest stomata length 29.9 μm and width 24.30 μm was noted in B. cristata. While shortest stomata length was observed in Ruellia prostrata 25.95 μm whereas minimum width of stomata was examined in Barleria acanthoides 2.05 μm. The diversity of trichomes are present in all species except in Ruellia brittoniana. Acanthaceae can be characterized by exhibiting different pollen morphology having five types of pollen shapes, prolate, spheroidal, perprolate, subprolate, and oblate spheroidal. Exine peculiarities showing variations such as reticulate, granulate, coarsely reticulate, lophoreticulate, perforate tectate, and granulate surface were examined. [ABSTRACT FROM AUTHOR]

Rhinacanthus spiciformis Y. F. Deng, Z. L. Lin & D. V. Hai, a new species from northern Vietnam previously misidentified as R. calcaratus is described and illustrated. This new species differs from all other Asian species of Rhinacanthus in the inflorescence being unbranched or comprised of trifurcate‐branched spikes, and the lower lip of corolla with conspicuous purple stripes near throat and on lobes. The pollen morphology and chromosome number are presented. It is proposed to be accessed as Least Concern (LC) according to the IUCN categories and criteria. [ABSTRACT FROM AUTHOR]

Examination of relevant type materials and living plants has revealed that Rungia axilliflora, R. densiflora and R. evrardii are conspecific with R. stolonifera. A lectotype is designated for the name R. stolonifera. Rungia sect. Stoloniferae is thus recognised as including two species, viz. R. stolonifera and R. mina. [ABSTRACT FROM AUTHOR]

Environmental variation along the geographical space can shape populations by natural selection. In the context of global warming and changing precipitation regimes, it is crucial to understand the role of environmental heterogeneity in tropical trees adaptation, given their disproportional contribution to water and carbon biogeochemical cycles. Here, we investigated how heterogeneity in freshwater availability along tropical wetlands has influenced molecular variations of the black mangrove (Avicennia germinans). A total of 57 trees were sampled at seven sites differing markedly in precipitation regime and riverine freshwater inputs. Using 2,297 genome‐wide single nucleotide polymorphic markers, we found signatures of natural selection by the association between variations in allele frequencies and environmental variables, including the precipitation of the warmest quarter and the annual precipitation. Additionally, we found candidate loci for selection based on statistical deviations from neutral expectations of interpopulation differentiation. Most candidate loci within transcribed sequences were functionally associated with central aspects of drought tolerance or plant response to drought. Moreover, our results suggest the occurrence of the rapid evolution of a population, probably in response to sudden and persistent limitations in plant access to soil water, following a road construction in 1974. Observations supporting rapid evolution included the reduction in tree size and changes in allele frequencies and in transcript expression associated with increased drought tolerance through the accumulation of osmoprotectants and antioxidants, biosynthesis of cuticles, protection against protein degradation, stomatal closure, photorespiration and photosynthesis. We describe a major role of spatial heterogeneity in freshwater availability in the specialization of this typically tropical tree. [ABSTRACT FROM AUTHOR]

Environmental cadmium (Cd) sources have increased in mangrove sediments in recent decades, inducing cellular damage to many plants. Avicennia schaueriana is abundant in mangrove sites and has been subject to Cd contamination. The possible effects of Cd toxicity and the structural and physiological disturbances to this plant were studied. Can this plant express early cellular tolerance mechanisms to such metal contamination?Seedlings of A. schaueriana were collected from sites of their natural occurrence, placed in plastic pots containing nutrient solution for 60 days, and subsequently exposed to increasing Cd concentrations for 5 days under experimental conditions. The anatomical, ultrastructural and physiological changes induced by Cd were analysed.Cd accumulated mainly in the root system and in pneumatophores, stems and leaves, induced differential accumulation of mineral nutrients, but did not induce necrosis or changes in leaf anatomy. However, there was a decrease in starch grains and an increase in deposited electron‐dense material in the cortex and vascular bundles. Cd induced both increases in calcium (Ca) content in shoots and Ca oxalate crystal precipitation in leaf mesophyll and was detected in crystals and in the secretion of salt glands.Our observations and experimental results provide evidence of Cd tolerance in A. schaueriana. As a new feature, despite the clear cellular physiological disorders, this plant is able to eliminate Cd through leaf salt glands and immobilise it in Ca crystals, representing fast mechanisms for Cd exclusion and complexation in leaves in heavy metal coastal polluted marine ecosystems. [ABSTRACT FROM AUTHOR]

The evolutionary origin of periodical mass‐flowering plants (shortly periodical plants), exhibiting periodical mass flowering and death immediately after flowering, has not been demonstrated. Within the genus Strobilanthes (Acanthaceae), which includes more than 50 periodical species, Strobilanthes flexicaulis on Okinawa Island, Japan, flowers gregariously every 6 years. We investigated the life history of S. flexicaulis in other regions and that of closely related species together with their molecular phylogeny to reveal the evolutionary origin of periodical mass flowering. S. flexicaulis on Taiwan Island was found to be a polycarpic perennial with no mass flowering and, in the Yaeyama Islands, Japan, a monocarpic perennial with no mass flowering. Molecular phylogenetic analyses indicated that a polycarpic perennial was the ancestral state in this whole group including S. flexicaulis and the closely related species. No distinctive genetic differentiation was found in S. flexicaulis among all three life histories (polycarpic perennial, monocarpic perennial, and periodical plant). These results suggest that among S. flexicaulis, the periodical mass flowering on Okinawa Island had evolved from the polycarpic perennial on Taiwan Island via the monocarpic perennial in the Yaeyama Islands. Thus, the evolution of life histories could have taken at the level of local populations within a species. [ABSTRACT FROM AUTHOR]

Chinese violet (Asystasia gangetica (L.) T. Anderson) is a perennial invasive weed belonging to Acanthaceae. Leaves of this weed have been suggested to possess phytotoxic activity. However, phytotoxic substances in this weed have not yet been reported. Therefore, the present study investigated phytotoxic activity of Chinese violet extracts and phytotoxic substances. The extracts of Chinese violet leaves inhibited the root and shoot growth of cress, lettuce, alfalfa, barnyard grass, ryegrass, and timothy, where the level of inhibition increased with increasing extract concentrations. Bioassay‐guided separations of the extracts led to isolation of two phytotoxic substances, indole‐3‐carboxaldehyde and (6R,9S)‐3‐oxo‐α‐ionol. Indole‐3‐carboxaldehyde significantly inhibited the root and shoot growth of cress at concentrations ≥100 and 30 μmol L−1, respectively, and concentrations of the substance required for 50% growth inhibition were 210 and 127 μmol L−1 for cress roots and shoots, respectively. The other substance, (6R,9S)‐3‐oxo‐α‐ionol, was reported to have strongly inhibited cress roots and shoots. The present results suggest that Chinese violet contains two phytotoxic substances indole‐3‐carboxaldehyde and (6R,9S)‐3‐oxo‐α‐ionol, and those substances may play an important role in the phytotoxic activity of Chinese violet. [ABSTRACT FROM AUTHOR]

Barleria is a genus of ~300 species of herbs and shrubs in Africa and Asia, with highest diversity in tropical East Africa and southern Africa. The genus is part of Barlerieae (Acanthaceae), a lineage that is distinguished from other Acanthaceae by quincuncial corolla aestivation. Unequivocal synapomorphies have yet to be identified for Barleria. However, among Barlerieae, species of Barleria can be recognized by the combination of 4‐partite calyces with the anterior and posterior lobes usually larger than the two lateral lobes, pollen with a coarsely reticulate (honeycomb) exine and the corolla limb variously subactinomorphic to strongly zygomorphic but never markedly bilabiate with a hooded upper lip. All Barleria that we have observed also have filaments that twist through 180° and cross just distal to the synstapetal zone. Barleria species have previously been classified into two subgenera and seven sections based on differences in leaf axil spine systems; configuration of the corolla, androecium and stigma; and morphology of the capsule and seed. We tested the subgeneric classification of Barleria by sampling 53 Barleria species and 9 outgroup species for three plastid intergenic spacers (trnS‐G, ndhF‐rpl32‐trnL(UAG)) and the nuclear region nrITS. We found a monophyletic Barleria and support for the two currently recognized subgenera; four of seven currently recognized sections are monophyletic but one of these four, sect. Fissimura, is nested within other sections. Species of sect. Fissimura unexpectedly resolved in subg. Barleria with strong support, although previous classifications placed the section in subg. Prionitis. We propose recognizing two subgenera (i.e., Barleria, Prionitis), the latter comprising three sections (i.e., Prionitis, Somalia, Stellatohirta). Barleria encompasses remarkable morphological diversity; we used an ultrametric tree to examine the evolution of nine morphological traits used to define infrageneric taxa in previous classifications. All characters evolved homoplasiously, but a few states (e.g., woody capsule septa) are supported as synapomorphies, and combinations of characters can be used to delimit subgenera. Members of subg. Barleria have 4‐seeded capsules that lack a prominent beak, with a transition to 2‐seeded capsules in the clade that corresponds to sect. Fissimura. In contrast, members of subg. Prionitis have 2‐seeded capsules (reversed to 4‐seeded in most members of one clade of sect. Somalia) that generally have a prominent beak. Additionally, we surveyed pollen morphology for 15 species sampled from across the classification. Pollen is consistently tricolporate with a coarse honeycomb exine. We provide an infrageneric classification and key to infrageneric taxa of Barleria. [ABSTRACT FROM AUTHOR]

Strobilanthes kannanii, a new species of Acanthaceae from southern Western Ghats is described and illustrated. It shows similarity to S. sessilis in some vegetative, floral and palynological characters. Notes on the habitat, distribution, and affinities are also provided along with color images and line drawings. [ABSTRACT FROM AUTHOR]

Abstract: The effect of processing on the biochemical contents of Acanthus montanus leaves was investigated. The moisture, crude protein, lipid, fiber, ash, and total carbohydrate contents of the raw vegetable were 59.15, 1.85, 2.32, 3.76, 2.04, and 34.65 g/100 g, respectively. The saponin, alkaloid, tannin, flavonoid, phenol, and anthocyanin contents of the raw vegetable were 5.35, 4.04, 1.10, 3.53, 2.87, and 1.27 g/100 g, respectively, while it contained 2.65 mg/100 g calcium, 1.14 mg/100 g magnesium, 7.66 mg/100 g potassium, 350.75 μg/g vitamin A, 50.87 mg/100 g vitamin C, and 0.25% titratable acidity. There were significant reductions (p < .05) in the protein, lipid, fiber, ash, saponin, alkaloid, tannin, phenol, anthocyanin, calcium, magnesium, potassium, vitamin A, vitamin C, and titratable acidity of the boiled or boiled + sun‐dried A. montanus leaves; significant elevation of the moisture contents but significant reduction of the total carbohydrate contents of the boiled; and significant reduction of the moisture contents of the boiled + sun‐dried vegetable compared with the raw. There were significant increases (p < .05) in the total carbohydrate contents of the boiled + sun‐dried leaves; significant reductions (p < .05) in the moisture, saponin, alkaloid, and vitamins A and C contents of the sun‐dried vegetable; and no significant differences (p > .05) in the lipid, calcium, potassium, and ash, but significant increases (p < .05) in the protein, crude fiber, total carbohydrates, tannins, flavonoids, phenols, anthocyanin, magnesium, and titratable acidity of the sun‐dried vegetable when compared with the raw. Sun drying alone either retained or enhanced the release of some important bioactive compounds in A. montanus leaves. Furthermore, the reduced moisture content of the sun‐dried vegetable together with its increased titratable acidity will make the sun‐dried vegetable uninhabitable for microorganisms, thereby increasing its shelf life. [ABSTRACT FROM AUTHOR]

Deserts, even those at tropical latitudes, often have strikingly low levels of plant diversity, particularly within genera. One remarkable exception to this pattern is the genus Petalidium (Acanthaceae), in which 37 of 40 named species occupy one of the driest environments on Earth, the Namib Desert of Namibia and neighboring Angola. To contribute to understanding this enigmatic diversity, we generated RADseq data for 47 accessions of Petalidium representing 22 species. We explored the impacts of 18 different combinations of assembly parameters in de novo assembly of the data across nine levels of missing data plus a best practice assembly using a reference Acanthaceae genome for a total of 171 sequence datasets assembled. RADseq data assembled at several thresholds of missing data, including 90% missing data, yielded phylogenetic hypotheses of Petalidium that were confidently and nearly fully resolved, which is notable given that divergence time analyses suggest a crown age for African species of 3.6-1.4 Ma. De novo assembly of our data yielded the most strongly supported and well-resolved topologies; in contrast, reference-based assembly performed poorly, perhaps due in part to moderate phylogenetic divergence between the reference genome, Ruellia speciosa, and the ingroup. Overall, we found that Petalidium, despite the harshness of the environment in which species occur, shows a net diversification rate (0.8-2.1 species per my) on par with those of diverse genera in tropical, Mediterranean, and alpine environments. [ABSTRACT FROM AUTHOR]

Rungia sinothailandica (Acanthaceae), a new species from Yunnan, China and Chiang Rai, Thailand is described and illustrated. A colour plate, line drawing and distribution map of R. sinothailandica are provided. Rungia sinothailandica is similar to R. pinpienensis H. S. Lo, but differs in the broadly ovate sterile bracts and obovate-elliptic fertile bracts, the crispate and tawny bracts margin, the 2-lobed upper lip of the corolla and puberulent capsule. It is also similar to R. burmanica (C. B. Clarke) B. Hansen, but is easily distinguished by pubescent stems and leaves, the cymbiform-oblong bracteoles and the 2-lobed upper lip of corolla. [ABSTRACT FROM AUTHOR]

Lepidagathis benojiana, a new species of Lepidagathis, collected from the Idukki district, Kerala, southern Western Ghats, India is described along with photographs. The new species is closely allied to L. chlorostachya Nees. but differs from the latter in its height, length of petiole, position and number of spikes, length of peduncle, length of floral whorls, colour of flower, colour and nature of stamens, nature of fruit and shape of the seed. [ABSTRACT FROM AUTHOR]

This is the first study in Acanthaceae to provide a robust and well-sampled phylogenetic framework for the "justicioid" lineage (Acanthaceae: Acanthoideae: Justicieae), a clade that includes at least 1000 species that together occupy essentially the entire distributional range of the family as a whole. Species are morphologically diverse and occupy a wide variety of habitats. Although much progress has been made in understanding phylogenetic relationships within Acanthaceae, well-sampled phylogenetic studies are lacking for justicioids. DNA sequence data from six regions for 178 accessions from across the entire lineage were used to test monophyly and validity of 17 putative genera of justicioids on a global scale. Included among these genera is the species-rich genus Justicia for which we evaluate the current morphology-based classification with a focus on Old World taxa. Our results strongly support monophyly of New World justicioids, including all New World species of Justicia plus species assigned to at least five other smaller genera. Further, with a greatly expanded taxon sample, we confirm our earlier unexpected result that Diclipterinae are embedded within justicioids. As traditionally circumscribed, Diclipterinae lack the morphological traits that mark justicioids and thus had not previously been associated with that group. This study further extends this unexpected result by placing a number of Old World justicioids in a clade that is sister to Diclipterinae. Although some genera of justicioids, notably of Diclipterinae, are monophyletic, Justicia is grossly polyphyletic. We explore these results by examining the diagnostic utility of morphological characters for major clades with a focus on inflorescences, androecia, pollen and seeds. We further use our results as context for documenting evolutionary patterns of floral traits and pollinator relationships, as well as biogeographic patterns, across this species-rich and diverse clade. [ABSTRACT FROM AUTHOR]

A series of new andrographolide-1,2,3-triazole derivatives, 3a, 3b, 3c, 3d, 3e, 3f, 3g, 3h, 3i, 3j, 3k, were synthesized from a natural bioactive labdane type diterpenoid, andrographolide. All the derivatives were screened against human cancer cell lines MCF7, MDA-MB-231, COLO205, HepG2, K562, Hela, and HEK293 to evaluate their cytotoxic activity. All the compounds showed anticancer activity selectively against K562 cell line, with IC50 values ranging from 8.00 to 17.11 µ M, and are inactive against the rest of the cell lines. Compounds 3c and 3d showed significant cytotoxicity among the synthesized derivatives. The in silico docking studies revealed compounds 3b and 3d with high binding affinity against the cancer target, transient receptor potential vanilloid 1. [ABSTRACT FROM AUTHOR]

Phylogenetic studies in Acanthaceae revealed that Schaueria azaleiflora and three species of Streblacanthus are closely related to the genus Pachystachys. In the present study, we propose the enlargement of Pachystachys to reflect these relationships. Two new species are described and illustrated, P. gracilis from Brazil and P. linearibracteata from Peru, and four new combinations are proposed in the genus. A key to identify the 18 species of Pachystachys s.l. is also provided. [ABSTRACT FROM AUTHOR]

PREMISE OF THE STUDY: Barleria is a large, pantropical genus of ca. 265 species mainly distributed in the Old World with only one species, B. oenotheroides, extending to the neotropics. This amphi-Atlantic disjunction, frequently displayed by pantropical taxa, has been traditionally explained with vicariance or geodispersal hypotheses and increasingly with long-distance dispersal. The native status of this species in the New World is controversial. METHODS: A molecular phylogeographic study based on the nuclear ribosomal ITS region and plastid trnL-F, rps16, and trnS-G sequences was done to clarify the origin of this tropical intercontinental disjunction. Divergence times were estimated with various analytical approaches, including different markers and primary calibration points. KEY RESULTS: Divergence ages estimated for Barleria lineages disagree with vicariance or geodispersal hypotheses. Genetic differentiation of American vs. African populations of B. oenotheroides does not support a recent anthropogenic introduction to the New World. Our data suggest ancient long-distance dispersal from the Old to the New World probably during the Pliocene or Upper Miocene. The number of dispersal events remains unclear. CONCLUSIONS: Our study demonstrates the native status of Barleria in the New World, resolving one of only three presumed natural Old World-New World disjunctions at the species level among Acanthaceae. This case constitutes a further documented example of the "out-of-Africa" pattern in the family, despite their lack of documented assisted-dispersal syndromes, and highlights the importance of long-distance dispersal to explain pantropical distributions in many families. [ABSTRACT FROM AUTHOR]

We examined invasive, casual (found occasionally outside cultivation) and non-invasive (found only in cultivation) species to investigate the role of species traits and two forms of biotic resistance (plant neighbours and herbivores) in limiting invasion in Hawaiian lowlands., Seeds of 21 species of common woody ornamentals from three plant families (Acanthaceae, Apocynaceae, Bignoniaceae) that are non-invasive, casual or invasive in Hawai'i were outplanted at two field sites. We measured germination of seeds and growth and survival of seedlings for 1 year in plots with and without neighbours from the naturally assembled community., The presence of neighbours reduced survival in some species, mostly non-invasive or casual species, and completely excluded two non-invasive species from community plots. Damage from the existing community of herbivores was correlated with lower survival in the Acanthaceae and Bignoniaceae, but not the Apocynaceae., Non-invasive and casual species had lower survival and growth rates than invasive species and lower photosynthetic rates in the presence of neighbours than invasive species. Non-invasives without neighbours also had lower specific leaf area than invasives and casuals., We found evidence for barriers to invasion in some non-invasive and casual species, including low growth rate, low survival, or low survival in the presence of neighbours. By contrast, five of the six invasives flowered and three began setting fruit within the duration of the experiment, as did one of the casual species., Synthesis. Our research demonstrates biotic resistance, presumably as a result of competition. Neighbouring plants reduced survival and growth for most species. For non-invasive species with low survival and growth even without competition from neighbouring plants, this resulted in complete exclusion from community plots or such low growth rates that exclusion over longer time frames was likely. We also provide evidence for traits-based barriers to invasion in non-invasive and casual species. However, no single barrier to invasion was shared across all non-invasive and casual species. [ABSTRACT FROM AUTHOR]

Extreme events such as storm surges and tsunamis in combination with subsidence of densely populated coastal areas pose an increasing threat to millions of people in the tropics. Intertidal mangrove forests may form a natural protection against some extreme events, but have also widely been destroyed by coastal development. The establishment of mangroves and the maintenance of their stability over the short- to long-term requires an understanding of sedimentary processes and landforms in the coastal zone, making geomorphology a crucial, but sometimes neglected discipline when attempting restoration for disaster risk reduction. Mangrove geomorphic setting varies markedly across the tropics, depending on abiotic parameters such as suspended sediment supply and tidal range, with different restoration strategies suitable for each. In this study we provide a global categorization of mangrove geomorphic settings, based on the literature and global remote sensing data. The world's mangroves can be broadly defined as: (1) minerogenic and high tidal range; (2) minerogenic and low tidal range; and (3) organogenic and low tidal range. We further discuss restoration and management approaches most suitable for each geomorphic setting. Overall, this study can be used to inform managers about the relevance of geomorphic knowledge for successful mangrove restoration, how an understanding of geomorphology can influence site selection and restoration success, and how to match specific restoration methods to the prevailing geomorphic context. The stronger incorporation of geomorphic knowledge into site planning and design will improve the success rates of restoration for this important and globally threatened ecosystem. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Onosma maculata Ranjbar & Almasi, a new Boraginaceae species endemic to Iran, is described and illustrated. The new species belongs to Onosma sect. Onosma subsect. Onosma. It is closely related to O. nervosa Riedl, but is easily distinguished by its spotted stem and peduncle (vs no spots), leaves 14-23 cm long (vs leaves 4-12 cm long), pedicel 5-15 mm long (vs pedicel 3-5 mm long), higher density of hairs, and glabrous nutlet (vs villous). Moreover, meiotic chromosome number and behavior were studied in two populations of the new species and it was found to be diploid with 2n = 2x = 16. [ABSTRACT FROM AUTHOR]

Acanthus mollis (Acanthaceae), Achillea ligustica, Artemisia arborescens and Inula viscosa (Asteraceae) are used in Southern Italy against psoriasis and other skin diseases that occur with an imbalanced production of eicosanoids. We here assessed their in vitro effects upon 5-, 12-, 15-LOX and COX-1 enzymes as well as NFκB activation in intact cells as their possible therapeutic targets. All methanol crude extracts inhibited both 5-LOX and COX-1 activities under 200 µg/mL, without significant effects on the 12-LOX pathway or any relevant in vitro free radical scavenging activity. NFκB activation was prevented by all extracts but A. mollis. Interestingly, A. ligustica, A. arborescens and A. mollis increased the biosynthesis of 15(S)-HETE, an anti-inflammatory eicosanoid. A. ligustica (IC50 =49.5 µg/mL) was superior to Silybum marianum (IC50 =147.8 µg/mL), which we used as antipsoriatic herbal medicine of reference. Its n-hexane, dichloromethane and ethyl acetate fractions had also inhibitory effects on the LTB4 biosynthesis (IC50 s=9.6, 20.3 and 68 µg/mL, respectively) evidencing that the apolar extracts of A. ligustica are promising active herbal ingredients for future phytotherapeutical products targeting psoriasis. [ABSTRACT FROM AUTHOR]

Pseuderanthemum pubescens T. Choopan & P. J. Grote, a new species from southeastern Thailand is described and illustrated. It is distinguished from P. longistylum J. B. Imlay by leaves being pubescent instead of glabrous and by the corolla lobes being purple with reddish purple dots on all 5 lobes instead of dotted on lower lip only. [ABSTRACT FROM AUTHOR]

The history of the discovery and naming of Strobilanthes nutans ( Nees) T. Anderson is provided. It is described and illustrated. Some of the problems in trying to subdivide the genus Strobilanthes are discussed in the context of highlighting the distinctive features of S. nutans including the distinctive cone-like inflorescence, the white flowers and the subglobose incurved anthers. The introduction and cultivation of S. nutans as well as the possibilities of the introduction of other hardy species of Strobilanthes are discussed. [ABSTRACT FROM AUTHOR]