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Summary: Angiosperm fossil woods of putative Eocene age from Corcovado, Chubut Province are described. They are placed in four taxonomic units: Weinmannioxylon trichospermoides and cf. Caldcluvioxylon of the Cunoniaceae, Myrceugenellites maytenoides of the Myrtaceae, and Nothofagoxylon ruei of the Nothofagaceae. The taxa in the assemblage are in accordance with similar fossil wood assemblages previously described from the Eocene and Oligocene of Patagonia. All the taxa are anatomically similar to trees that live today in Patagonia. Some of the woods show decay patterns by different saproxylic organisms. These include arthropod borings with coprolites and fungal remains in fungi-decayed tissues that are consistent with an active saproxylic community involved in the recycling of wood in the depositional paleoenvironment. [ABSTRACT FROM AUTHOR]

We describe nine angiosperm fossil woods from sediments of the Cardiel Formation (Upper Cretaceous) near the Cardiel Lake, Santa Cruz Province, Argentinian Patagonia. On the basis of the characteristics of the anatomy, the specimens were placed in three fossil species: Weinmannioxylon trichospermoides related to the Cunoniaceae, Burseroxylon panzai sp. nov. possibly related to the Anacardiaceae or Burseraceae, and a new taxon with unknown affinity, Tortorellixylon oligoporosum gen. et sp. nov. Angiosperms are 15% of the assemblage and conifers 85%, which is consistent with previous studies of fossil woods from the Late Cretaceous of Patagonia. Most specimens show poorly distinct growth ring boundaries that suggest a weakly marked annual seasonality during the deposition of the Cardiel Formation. In addition, the specimens' size and the rings' curvature are consistent with large trees. Decay patterns similar to those produced by modern xylophagous fungi are also recognized in most specimens. The identification of three species in an assemblage of nine fossil woods suggests a significant taxonomic richness of angiosperms, and the taxonomic composition suggests a Late Cretaceous age for the Cardiel Formation (probably Campanian–Maastrichtian). These new records allow a better understanding of the composition of the fossil forests of the Late Cretaceous of Patagonia, in which the tree canopy was apparently dominated by conifers. [ABSTRACT FROM AUTHOR]

Premise: Two distinct types of fossil infructescences from the early Eocene Laguna del Hunco flora, Chubut Province, Patagonia, Argentina, preserve features of the family Cunoniaceae. The goal of the study was to assess their affinities within Cunoniaceae and to interpret their evolutionary and biogeographical significance. Methods: Specimens were collected from the Tufolitas Laguna del Hunco, Huitrera Formation. They were prepared, photographed, and compared morphologically with similar extant and fossil fruits and infructescences using published literature and herbarium material. Results: The fruit and infructescence morphology place the fossil taxa within Cunoniaceae. They do not conform to any extant genus, supporting the erection of two new fossil genera. Racemofructus gen. nov. shares diagnostic features of the tribe Cunonieae, especially Weinmannia s.l., and exhibits two tribal morphological synapomorphies: a racemose inflorescence and a replum composed of a single column. Cunoniocarpa gen. nov. specimens are paniculate inflorescences with basipetally dehiscent, bicarpellate capsules that have persistent styles and calyces. Its replum morphology suggests an affinity to the tribe Caldcluvieae, particularly to the genus Ackama. Conclusions: The new Patagonian fossils described herein constitute the oldest record of cunoniaceous capsules globally, supplementing a significant body of fossil evidence from pollen, wood, and reproductive structures from southern South America and Antarctica that suggests that the Cunoniaceae were diversified and widely distributed in the southern hemisphere by the early Eocene. Racemofructus and Cunoniocarpa are, respectively, the first fossil records from South America of reproductive structures with affinity to tribes Cunonieae and Caldcluvieae. [ABSTRACT FROM AUTHOR]

Purpose: The Cunoniaceae are a major component of the New Caledonian flora with 91 endemic species that are highly unusual in that multiple metals are hyperaccumulated in different species. This makes it an ideal model system for studying the nature of the hyperaccumulation phenomenon. Methods: X-ray fluorescence spectroscopy (XRF) scanning of all herbarium collections of the Cunoniaceae was undertaken at the Herbarium of New Caledonia to reveal incidences of nickel (Ni) and manganese (Mn) accumulation. Following on, the Mn hyperaccumulating P. reticulata and the Ni hyperaccumulating P. xaragurensis were selected for detailed follow-up investigations using synchrotron-based X-ray fluorescence microscopy (XFM). Results: The systematic XRF screening of herbarium specimens showed that numerous species have high foliar Mn and Ni with species either accumulating Ni or Mn, but not both elements simultaneously. Soil 'extractable' Mn and Ni concentrations associated with Pancheria reticulata and P. xaragurensis greatly varies between the species. The XFM data shows that P. reticulata has a distinctive distribution pattern with Mn concentrated in large hypodermal cells. This contrasts with P. xaragurensis where Ni was mainly localized in and around the epidermis, and hypodermal cells were not observed. Conclusions: Manganese and Ni accumulation are differently localized in Pancheria species growing on ultramafic soils, which is not explained by contrasting soils conditions, but represents different ecophysiological adaptations. [ABSTRACT FROM AUTHOR]

Summary: Cunoniaceae are important elements of rainforests across the Southern Hemisphere. Many of these flowering plants are considered Paleo‐Antarctic Rainforest Lineages that had a Gondwanan distribution since the Paleocene. Fossils of several modern genera within the family, such as Ceratopetalum, have indicated biogeographical connections between South America and Australia in the Cenozoic.Here, we report a dramatic geographical range extension for Ceratopetalum, and Cunoniaceae as a whole, based on two exceptionally preserved fossil winged fruits from Campanian (c. 82–80 Ma old) deposits on Sucia Island, Washington, USA. The fossils were studied using physical sectioning, light microscopy, micro‐computed tomography scanning and multiple phylogenetic analyses.The fossil fruits share diagnostic characters with Ceratopetalum such as the presence of four to five persistent calyx lobes, a prominent nectary disk, persistent stamens, a semi‐inferior ovary and two persistent styles. Based on morphological comparisons with fruits of extant species and support from phylogenetic analyses, the fossils are assigned to a new species Ceratopetalum suciensis.These fossils are the first unequivocal evidence of crown Cunoniaceae from the Cretaceous of North America, indicating a more complicated biogeographical history for this important Gondwanan family. [ABSTRACT FROM AUTHOR]

New Caledonia is a global biodiversity hotspot known for its metal hyperaccumulator plants. X-ray fluorescence technology (XRF) has enabled non-destructive and quantitative determination of elemental concentrations in herbarium specimens from the ultramafic flora of the island. Specimens belonging to six major hyperaccumulator families (Cunoniaceae, Phyllanthaceae, Salicaceae, Sapotaceae, Oncothecaceae and Violaceae) and one to four specimens per species of the remaining ultramafic taxa in the herbarium were measured. XRF scanning included a total of c. 11 200 specimens from 35 orders, 96 families, 281 genera and 1484 species (1620 taxa) and covered 88.5% of the ultramafic flora. The study revealed the existence of 99 nickel hyperaccumulator taxa (65 known previously), 74 manganese hyperaccumulator taxa (11 known previously), eight cobalt hyperaccumulator taxa (two known previously) and four zinc hyperaccumulator taxa (none known previously). These results offer new insights into the phylogenetic diversity of hyperaccumulators in New Caledonia. The greatest diversity of nickel hyperaccumulators occur in a few major clades (Malphigiales and Oxalidales) and families (Phyllanthaceae, Salicaceae, Cunoniaceae). In contrast, manganese hyperaccumulation is phylogenetically scattered in the New Caledonian flora. [ABSTRACT FROM AUTHOR]

Introduction: High antioxidant levels have been linked with multiple therapeutic properties, including antibacterial activity. Therefore, high antioxidant plant preparations are good targets for antibacterial testing. D. pruriens has high antioxidant capacity although it is yet to be tested for the ability to inhibit the growth of bacterial pathogens. Methods: The ability of D. pruriens fruit and leaf extracts to inhibit the growth of a panel of bacterial and fungal pathogens was investigated by disc diffusion assay. Toxicity was examined using the Artemia franciscana nauplii bioassay. Results: All D. pruriens fruit and leaf extracts were completely ineffective at inhibiting the growth of gram-positive and gram-negative panels of bacteria, as well as fungi. The extracts were non-toxic in the Artemia bioassay following 24 h exposure. Conclusion: Despite their high antioxidant capacity, D. pruriens fruit and leaf extracts were completely ineffective bacterial and fungal growth inhibitors. However, these extracts may have other therapeutic properties and testing against protozoa, virus and tumour cells is required. [ABSTRACT FROM AUTHOR]

We studied the natural regeneration of Weinmannia lechleriana Engl. (Cunoniaceae) in a montane forest of the San Alberto Sector (Yanachaga-Chemillén National Park) in the central jungle of Peru. The natural regeneration was evaluated around ten mature trees, through the establishment of four transects of 20 meters in length. A total of 276 individuals were found around the ten trees, 57.2% corresponded to the category of seedlings, 40.9% of the saplings and only 1.8% to the category of poles. The average of natural regeneration individuals was 27 per evaluated tree, and the highest regeneration density was found between three and six meters around the tree, and then decreasing with increasing distance. Furthermore, a greater total abundance of individuals was found in the western transects and in trees evaluated in slope, but it would be necessary to evaluate a greater number of trees in order to reach a conclusion. Finally, we can indicate that Weinmannia lechleriana apparently would not present regeneration problems in the study area and it is recommended to continue with the studies of this species. [ABSTRACT FROM AUTHOR]

We present a comparative flower ontogenetic study in five species of the genus Eucryphia with the aim of testing whether differences in the organ number observed can be explained by changes in the meristematic size of floral meristem and floral organs. Species native to Oceania, viz. E. milliganii, E. lucida and E. moorei, have the smallest gynoecia with ca. 6 carpels, while the Chilean E. glutinosa and E. cordifolia present more than ten carpels. E. milliganii has the smallest flower with the lowest stamen number (ca. 50), while the other species produce around 200 stamens and more. Standardized measurements of meristematic sectors were taken in 49 developing flowers that were classified into three well-defined ontogenetic stages. Sizes of meristems varied significantly among species within each developmental stage as revealed by ANOVA analyses. Significant regressions between organ number and corresponding meristem size were consistent with the premise that a larger meristem size prior to organ initiation could be determining for a higher organ number. Flower organogenesis in Eucryphia also involves relevant meristem expansion while the organs are initiated, which results in a particular androecium patterning with a chaotic stamen arrangement. Meristem expansion also appears to be slower but more extensive in species with larger initial meristematic size, suggesting that flower phenotype can be determined in ontogeny by this heterochronic interplay of space and time. [ABSTRACT FROM AUTHOR]

• Background and Aims Early Palaeocene (Danian) plant fossils from Patagonia provide information on the recovery from the end-Cretaceous extinction and Cenozoic floristic change in South America. Actinomorphic flowers with eight to ten perianth parts are described and evaluated in a phylogenetic framework. The goal of this study is to determine the identity of these fossil flowers and to discuss their evolutionary, palaeoecological and biogeographical significance. • Methods More than 100 fossilized flowers were collected from three localities in the Danian Salamanca and Peñas Coloradas Formations in southern Chubut. They were prepared, photographed and compared with similar extant and fossil flowers using published literature and herbarium specimens. Phylogenetic analysis was performed using morphological and molecular data. • Key results The fossil flowers share some but not all the synapomorphies that characterize the Schizomerieae, a tribe within Cunoniaceae. These features include the shallow floral cup, variable number of perianth parts arranged in two whorls, laciniate petals, anthers with a connective extension, and a superior ovary with free styles. The number of perianth parts is doubled and the in situ pollen is tricolporate, with a surface more like that of other Cunoniaceae outside Schizomerieae, such as Davidsonia or Weinmannia. • Conclusions An extinct genus of crown-group Cunoniaceae is recognized and placed along the stem lineage leading to Schizomerieae. Extant relatives are typical of tropical to southern-temperate rainforests, and these fossils likely indicate a similarly warm and wet temperate palaeoclimate. The oldest reliable occurrences of the family are fossil pollen and wood from the Upper Cretaceous of the Antarctica and Argentina, whereas in Australia the family first occurs in upper Palaeocene deposits. This discovery demonstrates that the family survived the Cretaceous-Palaeogene boundary event in Patagonia and that diversification of extant lineages in the family was under way by the earliest Cenozoic. [ABSTRACT FROM AUTHOR]

Abstract: Male, female, pupa, larva and egg of a new genus and species of Gracillariidae (Ornixolinae), Cactivalva nebularia Moreira & Vargas gen. et sp. nov., from southern Brazil are described and illustrated with the aid of optical and scanning electron microscopy. A preliminary analysis of mitochondrial DNA sequences including members of related lineages is also provided. The immature stages are associated with Weinmannia paulliniifolia Pohl ex Ser. (Cunoniaceae) in high altitude cloud forest of northeast Rio Grande do Sul state. During the first two sap‐feeding instars, the larva forms a serpentine mine in the lowest layer of the spongy parenchyma of a leaflet. After moulting to the third instar, it moves to another leaflet, forming a blotch mine within which the last three tissue‐feeding instars complete development, feeding upon both spongy and palisade parenchyma. Pupation occurs outside the mine, within a cocoon built on the leaf surface. This is the third genus of gracillariid moths described from the Atlantic Forest, and the first gracillariid species ever known to be associated with the Cunoniaceae. [ABSTRACT FROM AUTHOR]

Background and Aims Radially symmetrical, five-winged fossil fruits from the highly diverse early Eocene Laguna del Hunco flora of Chubut Province, Patagonia, Argentina, are named, described and illustrated. The main goals are to assess the affinities of the fossils and to place them in an evolutionary, palaeoecological and biogeographic context. Methods Specimens of fossil fruits were collected from the Tufolitas Laguna del Hunco. They were prepared, photographed and compared with similar extant and fossil fruits using published literature. Their structure was also evaluated by comparing them with that of modern Ceratopetalum (Cunoniaceae) fruits through examination of herbarium specimens. Key Results The Laguna del Hunco fossil fruits share the diagnostic features that characterize modern and fossil Ceratopetalum (symmetry, number of fruit wings, presence of a conspicuous floral nectary and overall venation pattern). The pattern of the minor wing (sepal) veins observed in the Patagonian fossil fruits is different from that of modern and previously described fossil Ceratopetalum fruits; therefore, a new fossil species is recognized. An apomorphy (absence of petals) suggests that the fossils belong within crown-group Ceratopetalum. Conclusions The Patagonian fossil fruits are the oldest known record for Ceratopetalum. Because the affinities, provenance and age of the fossils are so well established, this new Ceratopetalum fossil species is an excellent candidate for use as a calibration point in divergence dating studies of the family Cunoniaceae. It represents the only record of Ceratopetalum outside Australasia, and further corroborates the biogeographic connection between the Laguna del Hunco flora and ancient and modern floras of the Australasian region. [ABSTRACT FROM AUTHOR]

A synopsis of Weinmannia of Mexico and Central America is presented. Ten species are recognized (W. anisophylla, W. balbisiana, W. burserifolia, W. fagaroides, W. intermedia, W. kars - teniana, W. pinnata, W. vulcanicola, W. wercklei), including the description of a new species (W. horrida J.F. Morales). A key to the species, as well as descriptions, illustrations, distribution, phenological data, and specimens examined are given for each.

Under the concept that Brunellia belongs to the Cunoniaceae rather thant being separated in Brunelliaceae, this paper examines the systematic position of Brunellia by studying the phylogentic relationships of this taxon with eleven ingrow taxa representing Cunoniaceae and using twenty characters. A total of twelve taxa represent the ingroup. The Hennig86 program based on parsimony was used to choose the hypotheses about relationships. The data of the internal group was analyzed first with four outgroups: Connarus, Davidsonia, Fothergilla y Quercus, then excluding Quercus and last with each of the outgroups independently. Data were polarized for the last analysis. Results showed that Brunellia does not belong to Cunoniaceae and Cunoniaceae is not a monophyletic group. I propose that Brunellia, and Spiraeanthemun-Acsmithia under a different family from Cunoniaceae. More research is necessary to corroborate the relationships of these taxa. The monophylyot the Cunoniaceae is also doubtful because some of its genera are nested with Davidsonia. The results also confirmed the relationships between the Rosidae and the lower Hamameliidae. Discussion about plesiomorphic and apomorphic states conditions are given for the Rosidae. The monophyly of none of Engler's tribes is confirmed.Bajo el concepto de que Brunellia es un táxon de Cunoniaceae y no una familia monogenérica Brunelliaceae, el presente trabajo examina la posición sistemática de Brunellia analizando las relaciones filogenéticas de este taxón con once taxones que representan a Cunoniaceae, con 20 caracteres morfológicos. Un total de doce taxones hacen parte del grupo interno. El programa Hennig86 basado en el método de simplicidad (parsimony) fue usado para la elección de las hipótesis de relaciones. Los datos del grupo interno fueron analizados primero con cuatro grupos externos: Connarus, Fothergilla, Davidsonia y Quercus,- con tres excluyendo a Quercusy con cada uno de ellos por separado; para este último caso los caracteres fueron polarizados. Los resultados muestran a Brunellia como taxón diferente de Cunoniaceae y a Cunoniaceae como grupo no monofilético. Se propone en este trabajo la inclusión de Brunellia, Spiraeanthemum- Acsmithia bajo una familia diferente de Cunoniaceae. Mayor investigación es necesaria para corroborar la hipótesis de relaciones de estos taxones. Se cuestiona también la monofilia de Cunoniaceae por la presencia de Davidsonia dentro del grupo interno. Se confirma la relación estrecha entre las Rosidae basales con las Hamameliidae inferiores. La apomortla y pleslomorfta de algunos caracteres es discutida. La monofilia de ninguna de las tribus de Engler es confirmada.

The phytochemical study of the leaves of Eucryphia cordifolia (Cunoniaceae) allowed for the isolation of six compounds: the triterpenes betulin (1) and 28-acetoxy betulin (3), the steroid β-sitosterol (2), the flavonol quercetrin (4), the flavanonol astilbine (5) and the flavanol catechin (6). The structures of the isolated compounds were clearly assigned through 1D and 2D-NMR, MS studies, and compared to previously described data. This is the first report on the isolation of compounds 1–4 and 6 from the genus Eucryphia. The chemotaxonomic importance of the isolated compounds within the family of Cunoniaceae-related plants is discussed. [Display omitted] • The phytochemical study of the leaves of Eucryphia cordifolia led to the isolation of six compounds. • Structural elucidation was carried out using NMR and HR-ESIMS. • Compounds 1, 2, 3 and 6 were first reported from the genus Eucryphia and the family Cunoniaceae. • Compounds 4 and 5 could be used as potential chemotaxonomic markers. [ABSTRACT FROM AUTHOR]

Esta es una familia característica de los bosques montanos húmedos. La familia Cunoniaceae es reconocida en el Perú por presentar un género, Weinmannia, y 41 especies (Brako & Zarucchi, 1993), todos arbustos y árboles. En este trabajo reconocemos seis especies y dos variedades como endemismos peruanos. Los taxones endémicos han sido encontrados en las regiones Mesoandina y Bosques Muy Húmedos Premontanos. Se aplicaron las categorías y criterios de la UICN a cinco especies. Dos especies endémicas se encuentran representadas dentro del Sistema Nacional de Áreas Naturales Protegidas por el Estado.

Contrasting signals of genetic divergence due to historic and contemporary gene flow were inferred for Coachwood, Ceratopetalum apetalum (Cunoniaceae), a wind-dispersed canopy tree endemic to eastern Australian warm temperate rainforest. Analysis of nine nuclear microsatellites across 22 localities revealed two clusters between northern and southern regions and with vicariance centred on the wide Hunter River Valley. Within populations diversity was high indicating a relatively high level of pollen dispersal among populations. Genetic variation was correlated to differences in regional biogeography and ecology corresponding to IBRA regions, primary factors being soil type and rainfall. Eleven haplotypes were identified by chloroplast microsatellite analysis from the same 22 localities. A lack of chloroplast diversity within sites demonstrates limited gene flow via seed dispersal. Network representation indicated regional sharing of haplotypes indicative of multiple Pleistocene refugia as well as deep divergences between regional elements of present populations. Chloroplast differentiation between sites in the upper and lower sections of the northern population is reflective of historic vicariance at the Clarence River Corridor. There was no simple vicariance explanation for the distribution of the divergent southern chlorotype, but its distribution may be explained by the effects of drift from a larger initial gene pool. Both the Hunter and Clarence River Valleys represent significant dry breaks within the species range, consistent with this species being rainfall dependent rather than cold-adapted. [ABSTRACT FROM AUTHOR]

The causes of the species richness of tropical trees are poorly understood, in particular the roles of ecological factors such as soil composition. The nickel( Ni)-hyperaccumulating tree genus Geissois (Cunoniaceae) from the South-west Pacific was chosen as a model of diversification on different substrates., Here, we investigated the leaf element compositions, spatial distributions and phylogeny of all species of Geissois occurring on New Caledonia., We found that New Caledonian Geissois descended from a single colonist and diversified relatively quickly into 13 species. Species on ultramafic and nonultramafic substrates showed contrasting patterns of leaf element composition and range overlap. Those on nonultramafic substrates were largely sympatric but had distinct leaf element compositions. By contrast, species on ultramafic substrates showed similar leaf element composition, but occurred in many cases exclusively in allopatry. Further, earlier work showed that at least three out of these seven species use different molecules to bind Ni., Geissois qualifies as a cryptic adaptive radiation, and may be the first such example in a lineage of tropical forest trees. Variation in biochemical strategies for coping with both typical and adverse soil conditions may help to explain the diversification and coexistence of tropical forest trees on similar soil types. [ABSTRACT FROM AUTHOR]

Comparison of the four species groups comprising the tribe Geissoieae (Lamanonia in South America, Geissois sensu stricto from islands in the south-western Pacific, and Pseudoweinmannia and Geissois in Australia) showed differences in the stipules, inflorescences and flowers. Molecular phylogenetic analyses suggested that Geissois sensu lato is paraphyletic, with Australian Geissois being closer to Pseudoweinmannia than toNewCaledonian Geissois. The name Karrabina is published to accommodate the Australian species formerly placed in Geissois, namely K. benthamiana Rozefelds & H.C.Hopkins and K. biagiana Rozefelds & H.C.Hopkins. Distinguishing characters for Karrabina are: four lateral stipules per node that vary from free to largely fused between and sometimes across the petioles; inflorescences with a variable number of metamers and racemes, with both median and lateral modules that always lack a median raceme; and pale flowers with five or six calyx lobes and shortly exserted stamens. Geissois s.s. differs in having: two intrapetiolar stipules per node; inflorescences consisting of few metamers and few racemes, with the modules being always lateral and possessing a median raceme; flowers with four red calyx lobes and prominently exserted stamens. The generic limits of Lamanonia and Pseudoweinmannia remain unchanged. [ABSTRACT FROM AUTHOR]

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Weinmannia marquesana F. Br. var. angustifolia Lorence & W. L. Wagner, var. nov., a new variety with narrow, simple leaves endemic to Tahuata, Marquesas Islands (French Polynesia) is described and its affinities and conservation status are discussed. It is similar to the other two varieties of this species by having simple leaves, but this new variety has much narrower leaf blades, and it resembles W. tremuloides in having narrow leaf blades but differs by having simple, not trifoliolate leaves. [ABSTRACT FROM AUTHOR]

Tracing the tunnels of wood boring larvae in wood or other plant material is generally a difficult and destructive process. Here we present a novel non-destructive method using an in vivo micro-CT scanner to obtain tomograms of small tunnels. The tunnels were formed by larval xiphydriid woodwasps in the branches of the Tasmanian tree Anodopetalum biglandulosum (Cunoniaceae) and show that, as the larvae develop, the tunnels become progressively larger until pupation occurs just below the surface of the bark. The adult then chews its way through the remaining wood and bark before emerging. This non-destructive method is discussed more broadly in regard to its application for tracing the tunnels of wood boring insects, for detecting insects in grain and other plant material for quarantine purposes, and for tracking the tunnelling behaviour and development of live insects in wood. [ABSTRACT FROM AUTHOR]

Numerous studies have examined how leaf temperature affects photosynthesis, but few have investigated photosynthetic temperature sensitivity during leaf expansion. Here, we show that immature leaves (~18% of final leaf area) of the common New Zealand tree, Weinmannia racemosa L. f. (Cunoniaceae), are less sensitive than mature leaves to rapid increases in leaf temperature (from 25 to 35 °C) as measured by chlorophyll a fluorescence. Relative differences in the tolerance of photosystem II to heat were supported by solute leakage experiments, in which disks from immature leaves incubated at 47 °C lost significantly fewer solutes than did disks from mature leaves. In addition, levels of trienoic (18:3) fatty acids were far lower in immature than in mature leaves (low levels are known to be associated with photosynthetic thermotolerance). The developmental changes in photosynthetic tolerance to heat stress likely correspond to compositional differences of the thylakoid membranes during leaf expansion. This result may be useful in understanding photosynthetic responses to temperature in young leaves which lack functioning stomates, or under extreme conditions when leaf temperatures are high or fluctuate rapidly. [ABSTRACT FROM AUTHOR]

The Oceanian plant genus Spiraeanthemum (Cunoniaceae) has a centre of diversity in New Caledonia, where it is represented by seven species. Its diversification was investigated using two low-copy nuclear genes, ncpGS and GapC, and phylogenetic analyses were based on maximum parsimony, maximum likelihood and recombination networks. We detected several cases of gene recombination in both datasets, and these have obscured the history within the genus. For S. ellipticum and S. pubescens, accessions from southern populations on ultramafic soils were genetically distinct from accessions from northern populations on non-ultramafic soils. Given that no obvious morphological characters distinguish northern and southern populations in either taxon, both may be considered as examples of cryptic species. Incongruence between gene trees and species' delimitation may be explained by the parallel evolution of similar morphology, differential lineage sorting leading to differential fixation of alleles or different introgression patterns in the north and south leading to allele displacement. In New Caledonia, some species with broad ecological preferences may thus be artificial concepts. This suggests that they should be treated more critically in monographs and that the species' richness of the New Caledonian flora may be underestimated. Problems associated with the typification of S. ellipticum and evidence of hybridization events in the history of Spiraeanthemum are also discussed. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 161, 137–152. [ABSTRACT FROM AUTHOR]

We reconstructed the evolutionary history of Codia, a plant genus endemic to the New Caledonia biodiversity hotspot in the southwest Pacific, using three single-copy nuclear genes. It seems likely that more than half of Codia species have a hybrid origin, but in the absence of cytological information, it is not known whether polyploids occur. Adaptation to ultramafic soils is possibly a plesiomorphic character for the entire genus. We found that species of hybrid origin can have some morphological characters absent in putative parental species, that is, they exhibit transgressive phenotypes. There is evidence of considerable range alteration post-origin in several species because some likely parental species of hybrid taxa no longer co-occur and are confined to putative rainforest refugia; in some cases, hybrid species do not now co-occur with either of their parental species. These results have implications for the design of conservation strategies, for example, prioritization of parental species for ex-situ conservation and preservation of the contact zones between soil types where hybridization is more likely to occur (i.e. conserving the possibility for the process to continue rather than trying to conserve taxa). [ABSTRACT FROM AUTHOR]

Rhysacephala warraensis Jennings & Austin, sp. nov., (Hymenoptera: Xiphydriidae), is described, being the first record of a xiphydriid woodwasp from Tasmania. Four females were reared from ‘horizontal’, Anodopetalum biglandulosum (Cunoniaceae), the first confirmed host record for an Australian xiphydriid. [ABSTRACT FROM AUTHOR]

It is generally assumed that there is a good correlation between systematics and the secondary compounds found in plants However because of the frequent homoplasy of chemical characters this has been difficult to test using statistical methods. Here we applied two nonparametric tests on a published data set, where 50 species of New Caledonian Cunoniaceae were screened for bioactivity against several pathogenic strains. Using Moran's I index we showed that in two of nine tests against pathogenic strains there was a significantly higher similarity than expected in bioactivities between species belonging to the same genus and a significantly higher than expected dissimilarity in bioactivity between species belonging to different tribes. When considering the bioactivities against all pathogenic strains with Mantel tests, we also found significant correlation between bioactivity and phylogenetic distance in two of four tests. This has implications in screening and conservation. Searches for new molecules and bioactivity should preferentially be made on species spread across the tree of life. There is also a need to preserve as much phylogenetic diversity as possible to make sure that the widest reservoir of natural compounds remains available for future generations. [ABSTRACT FROM AUTHOR]

Abstract: Marked morphological changes occur during development from young seedlings to adults in Geissois pruinosa. At successive stages, leaves change from simple to trifoliolate and finally to 5-foliolate, palmately compound leaves, the margin of the blades changes from dentate to entire, the venation from craspedodromous to brochidodromous, and the stipules switch at about the 7th level from four free lateral ones per node to two fused intrapetiolar ones. Stems and leaves in young seedlings have sparse, erect hairs, but are glabrous in adults. Scattered and often incomplete information on other Cunoniaceae suggest that differences between seedlings and adults in other genera are generally less pronounced. Some seedling characters of G. pruinosa (including toothed leaflet margins and free lateral stipules) occur in the adult foliage of some of its close relatives (the genera Lamanonia and Pseudoweinmannia and Geissois in Australia) and are plesiomorphic within this clade. [Copyright &y& Elsevier]

The article provides a study which analyses the relationship of Acsmithia and Spiraeanthemum on the tribe of Spiraeanthemae. The study sequenced the two nuclear single copy genes and one plastid region as its molecular markers. Results of the study reveals that the phyllotaxy and sexual system characteristics of Acsmithia and Spiraeanthemum that distinguishes them are homoplasious in other Cunoniaceae groups.

Geissois sensu stricto (i.e. excluding the Australian species of this genus) has 19 species restricted to islands in the south-west Pacific and is the sole group in Cunoniaceae in which the stipules are intrapetiolar (axillary) in the adult foliage. In apical buds, paired opposite stipules are coherent round their margins and are either clearly intrapetiolar in relation to the most distal pair of developed leaves (Type I, most species), or they appear interpetiolar due to the abortion of the pair of leaves associated with them and the failure of the internode proximal to them to elongate (Type II, a few species). Stipules are often accrescent and the largest in the family occur in this group, reaching 10 cm long in some species. The ornithophilous racemose inflorescences of members of this group normally consist of either axillary triads ( G. hirsuta only) or apparently simple, unbranched racemes which are ramiflorous or occasionally axillary. However, bract scars on the axes proximal to the flowers show that both types of inflorescence module usually consist of two metamers. The structure of the inflorescences and stipules in Geissois sensu stricto supports the distinction between this group and the Australian species traditionally included in Geissois sensu lato. [ABSTRACT FROM AUTHOR]

Descriptions, illustrations, distribution maps and conservation assessments are provided for two new species of Cunonia from New Caledonia. Cunonia dickisonii Pillon & H. C. Hopkins is endemic to montane ultramafic scrub at high elevation on Mts Humboldt and Kouakoué. Cunonia koghicola H. C. Hopkins, J. Bradford & Pillon is from wet forest at low to medium elevation in the region of Mt Koghi, and irregularities in leaf shape and venation suggest it may be of hybrid origin. Microendemism on Mt Humboldt and Mt Kouakoué is briefly discussed. [ABSTRACT FROM AUTHOR]

Plants growing on serpentine soils are usually assumed to be nickel (Ni)-tolerant species. The objective of the work reported here was to find out whether Cunonia macrophylla Brongniart & Gris, an endemic species common on Ni-rich soils in New Caledonia, is indeed Ni tolerant. In a greenhouse experiment, plants were watered with solutions containing Ni chloride (5 to 1000 mg Ni L -1 ) for 15 months before their morphological characteristics were measured, and the levels of nitrate, protein, and nutrients in the plants were determined. The plants grown with 5, 10, 50, and 100 mg Ni L -1 had more leaves, and there was a tendency toward greater stem thickness and fresh shoot biomass at 50 mg Ni L -1 . Manganese (Mn), copper (Cu), and zinc (Zn) concentrations were also higher in the presence of 50 mg Ni L -1 . One thousand mg Ni L -1 induced symptoms of Ni toxicity, and this effect may account for the lower concentration of potassium (K) in the shoots and roots of plants exposed to this concentration, as well as for inducing higher concentrations of soluble protein in the shoots. Calcium (Ca) and iron (Fe) levels were lower in roots exposed to higher concentrations of Ni. Nickel concentrations in the plant as a whole increased with the level of Ni applied, and the Ni gradient decreased from roots to stem and from stem to leaves. It was concluded that Cunonia macrophylla is a Ni-tolerant species that accumulates Ni without any impairment of growth when exposed to levels of up 500 mg Ni L -1 . [ABSTRACT FROM AUTHOR]

Abstract: Chemical study of Cunonia macrophylla, a New Caledonian Cunoniaceae, based on bioactive effects of a crude methanol extract of the leaves, detected bioactive tannins for the first time in this plant family. These ellagitannins have been identified as ellagic acid-4-O-β-d-xylopyranoside (6), mallorepanin (3), mallotinic acid (1) along with corilagin (2), chebulagic acid (4), ellagic acid (5) and gallic acid (7) and have been shown to possess antimicrobial activity and to inhibit xanthine oxidase. Antimicrobial effects on bacterial human pathogens (Staphylococcus aureus, Corynebacterium accolans) and on a plant pathogen (Erwinia carotovora) as well as on a human pathogenic yeast (Candida albicans) were investigated. Activity is reported here for the first time for compounds 1, 3, 4 and 6. The inhibitory effects of all molecules against xanthine oxidase in relation to their structure was evaluated and compared. Compound 6 presented the best activity and seems to be of considerable interest for further studies. [Copyright &y& Elsevier]