Low-Temperature X-ray Microanalysis Sheds New Light on Mineral Nutrition Aspects of Insect Leaf Galling.

Manipulation of host plant physiology by leaf-galling insects is a multifaceted process. Among fundamental knowledge gaps surrounding this scientifically intriguing phenomenon is the appropriation of plant mineral nutrients and moisture for galling advantage. Small, soluble mineral ions and watery cell contents in dense gall tissues risk disruption during routine sample preparations. In this study, an X-ray microanalysis was applied to investigate gall mineral nutrition. Morphologically diverse leaf galls were sampled from three Australian rainforest tree species. Using cryo-analytical scanning electron microscopy, real-time X-ray analytical maps of cellular mineral nutrients and water were integrated with anatomical images of gall and leaf cross-sectional surfaces. A comparison of host-leaf and gall anatomies bore direct evidence of drastic changes to leaf cells through the galling process. Distinct "wet" and "dry" regions within galls were anatomically and/or chemically differentiated, suggesting specific functionality. "Wet" regions comprising hydrated cells including soft gall-cavity linings where larvae are known to feed contained soluble plant mineral nutrients, while C-rich "dry" tissues largely devoid of mineral nutrients likely contribute structural support. Mapping immobile nutrients such as Mn may provide a means of "matching" specific gall cell types to those in ungalled host-leaf tissues. The findings here provided otherwise inaccessible insights into leaf-gall mineral nutrition.

Isolation, Identification, and Analysis of Potential Functions of Culturable Bacteria Associated with an Invasive Gall Wasp, Leptocybe invasa.

Symbioses between invasive insects and bacteria are one of the key drivers of insect invasion success. Gall-inducing insects stimulate host plants to produce galls, which affects the normal growth of plants. Leptocybe invasa Fisher et La Salle, an invasive gall-inducing wasp, mainly damages Eucalyptus plantations in Southern China, but little is known about its associated bacteria. The aim of this study was to assess the diversity of bacterial communities at different developmental stages of L. invasa and to identify possible ecological functions of the associated bacteria. Bacteria associated with L. invasa were isolated using culture-dependent methods and their taxonomic statuses were determined by sequencing the 16S rRNA gene. A total of 88 species belonging to four phyla, 27 families, and 44 genera were identified by phylogenetic analysis. The four phyla were Proteobacteria, Actinobacteria, Firmicutes, and Bacteroidetes, mainly from the genera Pantoea, Enterobacter, Pseudomonas, Bacillus, Acinetobacter, Curtobacterium, Sphingobium, Klebsiella, and Rhizobium. Among them, 72 species were isolated in the insect gall stage and 46 species were isolated from the adult stage. The most abundant bacterial species were γ-Proteobacteria. We found significant differences in total bacterial counts and community compositions at different developmental stages, and identified possible ecological roles of L. invasa-associated bacteria. This study is the first to systematically investigate the associated bacteria of L. invasa using culture-dependent methods, and provides a reference for other gall-inducing insects and associated bacteria.

Recent Progress Regarding the Molecular Aspects of Insect Gall Formation.

Galls are characteristic plant structures formed by cell size enlargement and/or cell proliferation induced by parasitic or pathogenic organisms. Insects are a major inducer of galls, and insect galls can occur on plant leaves, stems, floral buds, flowers, fruits, or roots. Many of these exhibit unique shapes, providing shelter and nutrients to insects. To form unique gall structures, gall-inducing insects are believed to secrete certain effector molecules and hijack host developmental programs. However, the molecular mechanisms of insect gall induction and development remain largely unknown due to the difficulties associated with the study of non-model plants in the wild. Recent advances in next-generation sequencing have allowed us to determine the biological processes in non-model organisms, including gall-inducing insects and their host plants. In this review, we first summarize the adaptive significance of galls for insects and plants. Thereafter, we summarize recent progress regarding the molecular aspects of insect gall formation.

Metabolic and functional distinction of the Smicronyx sp. galls on Cuscuta campestris.

MAIN CONCLUSION: The weevil gall contains two distinct regions, differing in hydrolytic and antioxidant enzymes activity and profiles, which is also functionally distinct from the non-infected Cuscuta stems. Weevils of the genus Smicronyx are gall-forming insects, widely distributed on parasitic flowering plants of the genus Cuscuta. Thus, they are considered epiparasites and potential method for biological control of their agriculturally harmful hosts. Although several reports on gall formation in Cuscuta spp. exist, the metabolic and functional changes, occurring in the gall, remained largely unknown. Smicronyx sp. galls, collected from a wild Cuscuta campestris population, were dissected into two distinct regions, inner and outer cortex, defined by the higher chlorophyll content of the inner cortex. Based on hydrolytic and antioxidant enzymes activity and isoenzymatic profiles as analyzed after electrophoretic separation, we suggested that the gall differs in its metabolic activity from the non-infected plant tissue. While the outer cortex serves as a region of nutrient storage and mobilization, the inner cortex is directly involved in larvae nutrition. The increase in metabolic activity resulted in significantly increased superoxide dismutase activity in the gall, while several other antioxidant enzymes diminished. The present research offers new insights into the functionally differing regions of Smicronyx galls and the metabolic changes, induced in C. campestris in result of the gall formation.

Differences in Monoterpene Biosynthesis and Accumulation in Pistacia palaestina Leaves and Aphid-Induced Galls.

Certain insect species can induce gall formation on numerous plants species. Although the mechanism of gall development is largely unknown, it is clear that insects manipulate their hosts' anatomy, physiology, and chemistry for their own benefit. It is well known that insect-induced galls often contain vast amounts of plant defensive compounds as compared to non-colonized tissues, but it is not clear if defensive compounds can be produced in situ in the galled tissues. To answer this question, we analyzed terpene accumulation patterns and possible independent biosynthetic potential of galls induced by the aphid Baizongia pistaciae L. on the terminal buds of Pistacia palaestina Boiss. We compared monoterpene levels and monoterpene synthase enzyme activity in galls and healthy leaves from individual trees growing in a natural setting. At all developmental stages, monoterpene content and monoterpene synthase activity were consistently (up to 10 fold on a fresh weight basis) higher in galls than in intact non-colonized leaves. A remarkable tree to tree variation in the products produced in vitro from the substrate geranyl diphosphate by soluble protein extracts derived from individual trees was observed. Furthermore, galls and leaves from the same trees displayed enhanced and often distinct biosynthetic capabilities. Our results clearly indicate that galls possess independent metabolic capacities to produce and accumulate monoterpenes as compared to leaves. Our study indicates that galling aphids manipulate the enzymatic machinery of their host plant, intensifying their own defenses against natural enemies.

Functional Characterization of the Photosynthetic Machinery in Smicronix Galls on the Parasitic Plant Cuscuta campestris by JIP-Test.

Members of the genus Cuscuta are generally considered to be non-photosynthetic, stem-holoparasitic flowering plants. Under certain circumstances, at least some members of the genus are capable of limited photosynthesis. The galls of the Smicronyx weevils formed on Cuscuta campestris are particularly rich in chlorophylls compared to the stem of the parasitic plant. In the present study, we aimed to characterize the photosynthetic activity in the inner and outer gall cortices in comparison to the non-photosynthetic stems and a reference plant (Arabidopsis thaliana). The recorded prompt chlorophyll fluorescence transients were analyzed using JIP test. Detailed analysis of the chlorophyll fluorescence confirmed the presence of actively functioning photosynthetic machinery, especially in the inner cortex of the galls. This photosynthesis, induced by the insect larvae, did not reach the levels of the photosynthetic activity in Arabidopsis thaliana plants. Thylakoid protein complexes were identified by separation with two-dimensional Blue Native/SDS PAGE. It appeared that some of the complexes presented in A. thaliana are missing in C. campestris. We hypothesize that the insect-triggered transition from non-photosynthetic to photosynthetic tissue in the gall is driven by the increased requirements for nutrients related to the larval nutrition.

The Diversity and Dynamics of Fungi in Dryocosmus kuriphilus Community.

Dryocosmus kuriphilus (Hymenoptera: Cynipidae) is a gall wasp that induces insect galls on chestnut trees and results in massive yield losses worldwide. Fungi can cause the necrosis of chestnut trees and the death of gall wasps. The aim of this research was to investigate the potential role of D. kuriphilus in the transmission of fungi. We sequenced the ribosomal RNA internal transcribed spacer region 1 of fungi in D. kuriphilus adults, associated insect galls and the galled twigs of Castanea mollissima, using high-throughput sequencing. We compared the species richness, α-diversity and community structure of fungi in D. kuriphilus adults, insect galls and the galled twigs. We provide the first evidence that D. kuriphilus adults shared most fungal species with associated insect galls and the galled twigs, and were dominated by Botryosphaeria sp., Aspergillus sp. and Diaporthe sp. We suggest D. kuriphilus adults may be potential vectors of plant pathogens and may facilitate the transmission of fungi between chestnut trees. Furthermore, the fungi may horizontally transmit among D. kuriphilus adults, associated insect galls and the galled twigs.

Comparison of Auxin and Cytokinins Concentrations, and the Structure of Bacterial Community between Host Twigs and Lithosaphonecrus arcoverticus Galls.

Insect galls are the abnormal growth of plant tissues induced by a wide variety of galling insects and characterized by high concentrations of auxins and cytokinins. It remains unclear whether the auxins and cytokinins affect the bacterial community structure of insect galls. We determined the concentrations of indoleacetic acid (IAA) as an example of auxin, trans-zeatin riboside (tZR) and isopentenyladenine (iP) as cytokinins in Lithosaphonecrus arcoverticus (Hymenoptera: Cynipidae) galls and the galled twigs of Lithocarpus glaber (Fagaceae) using liquid chromatography-tandem mass spectrometry. Moreover, for the first time, we compared the bacterial community structure of L. arcoverticus galls and galled twigs by high-throughput sequencing, and calculated the Spearman correlation and associated degree of significance between the IAA, tZR and iP concentrations and the bacterial community structure. Our results indicated the concentrations of IAA, tZR and iP were higher in L. arcoverticus galls than in galled twigs, and positively correlated with the bacterial community structure of L. arcoverticus galls. We suggest the high concentrations of IAA, tZR and iP may affect the bacterial community structure of L. arcoverticus galls.

Plant-galling insect interactions: a data set of host plants and their gall-inducing insects for the Cerrado.

Recent decades have seen increased research interest in the processes and mechanisms related to insect gall richness and host plants. The data set provided here includes 968 records of interactions between galling insects and host plants for the Cerrado biome. The data set comprises 505 species of 222 genera and 67 families of host plants. The botanical families most represented in the data set are Asteraceae, Fabaceae, Myrtaceae, Malpighiaceae, and Melastomataceae, which account for ~48.5% of all records and 52% of the total number of species. The gall-inducing insects listed in the data set include 48 species of Cecidomyiidae and one species of Tephritidae. This data set is the first to compile inventories of plant-galling insect communities and information about the diversity and distribution of insect galls and their host plants in the Cerrado. The data set reveals knowledge gaps and opportunities for future research on patterns of diversity and distribution, and provides a basis for generating and testing new ecological hypotheses. Please cite this data paper when using the current data in publications and let us know how the data are used in the publications. There are no copyright restrictions.

A peculiar new species of gall-inducing, clearwing moth (Lepidoptera, Sesiidae) associated with Cayaponia in the Atlantic Forest.

Larvae of most clearwing moths (Lepidoptera, Sesiidae) are endophagous borers of many angiosperms, including their fruits, stems, and roots. Their localized feeding may lead to swellings on those plant parts, but whether the structures produced should be considered true galls is still controversial. In this study we describe a peculiar sesiid moth, Neospheciacecidogena sp. nov. whose larvae induce unusual, external galls on Cayponiapilosa (Vell.) Cogn. (Cucurbitaceae) in the Atlantic Forest of southernmost Brazil. The adults, egg, larva, pupa and the gall are described and illustrated based on light and scanning electron microscopy. Galls are cylindrical and unilocular; they are induced individually on axillary buds of the C.pilosa stem. Unlike larvae of other sesiids, those of N.cecidogena sp. nov. lack abdominal pseudopodia, and show reduced stemata and chaetotaxy. Pupation occurs inside the gall, after having overwintered in the last larval instar. A maximum likelihood tree constructed based on mitochondrial DNA (COI) sequences showed that N.cecidogena sp. nov. is monophyletic and has an average distance of 13% to species of Melittia. The genera Neosphecia Le Cerf, 1916 stat. rev., Premelittia Le Cerf, 1916 stat rev., and Melittina Le Cerf, 1917 stat. rev. are restored from synonyms of Melittia Hübner, 1819 ["1816"].

Overlooked gall-inducing moths revisited, with the description of Andescecidiumparrai gen. et sp. n. and Olierasaizi sp. n. from Chile (Lepidoptera, Cecidosidae).

There are still many gall systems associated with larvae of Lepidoptera in which the true gall-inducers have not been identified to species. Reports on misidentification of gall inducers have been recurrent for these galls, particularly in complex gall-systems that may include inquilines, kleptoparasites, and cecidophages, among other feeding guilds such as predators and parasitoid wasps. Here we describe and illustrate the adults, larvae, pupae and galls, based on light and scanning microscopy, of Andescecidiumparrai gen. et sp. n. and Olierasaizi sp. n., two sympatric cecidosid moths that are associated with Schinuspolygamus (Cav.) Cabrera (Anacardiaceae) in central Chile. Adults, immatures, and galls of the former did not conform to any known cecidosid genus. Galls of A.parrai are external, spherical, and conspicuous, being known for more than one century. However, their induction has been mistakenly associated with either unidentified Coleoptera (original description) or Olieraargentinana Brèthes (recently), a distinct cecidosid species with distribution restricted to the eastern Andes. Galls of O.saizi had been undetected, as they are inconspicuous. They occur under the bark within swollen stems, and may occur on the same plant, adjacent to those of A.parrai. We also propose a time-calibrated phylogeny using sequences from mitochondrial and nuclear loci, including specimens of the new proposed taxa. Thus in addition to clarifying the taxonomy of the Chilean cecidosid species we also tested their monophyly in comparison to congeneric species and putative specimens of all genera of Neotropical and African cecidosids.

Cecidonius pampeanus, gen. et sp. n.: an overlooked and rare, new gall-inducing micromoth associated with Schinus in southern Brazil (Lepidoptera, Cecidosidae).

Galls induced by the larval stage of cecidosids (Lepidoptera: Cecidosidae) are complex, multi-trophic systems, still poorly studied. They may be associated with other insect feeding guilds, including inquilines, kleptoparasites, cecidophages, parasitoids, and predators. By causing death of the gall inducer early in life and altering the gall phenotype, inquilines may lead to misidentification of the true gall inducers. Here, we describe through light and scanning electron microscopy Cecidonius pampeanus, a new genus and species of cecidosid moth, from the Pampa biome, south Brazil. It induces unnoticed, small galls under swollen stems of Schinus weinmannifolius Mart. ex Engl. (Anacardiaceae). Such galls are severely attacked early in ontogeny either by unidentified parasitoids belonging to Lyrcus Walker (Pteromalidae) that feed upon the inducer, or by inquiline wasps of the genus Allorhogas Gahan (Braconidae). The inquilines modify the galls into large ones that last longer and promptly call attention. Free-living galls are rare and dehiscent, pupation of C. pampeanus occurring on the ground. Due to these reasons the true inducer has been overlooked in this case for more than a century. Additionally we inferred a phylogeny for Cecidosidae using sequences from mitochondrial and nuclear loci, and characterized genetic variation and gene flow across ten populations. Despite its natural history similarities with the African genus Scyrotis, Cecidonius is a much younger lineage, more closely related to the Neotropical cecidosids. C. pampeanus populations, which are now confined to a few mountain areas within its distribution range due to habitat destruction, are also genetically isolated, requiring conservation measures.

Development of a HS-SPME-GC/MS protocol assisted by chemometric tools to study herbivore-induced volatiles in Myrcia splendens.

A headspace solid phase microextraction (HS-SPME) method combined with gas chromatography-mass spectrometry (GC/MS) was developed and optimized for extraction and analysis of volatile organic compounds (VOC) of leaves and galls of Myrcia splendens. Through a process of optimization of main factors affecting HS-SPME efficiency, the coating divivnilbenzene-carboxen-polydimethylsiloxane (DVB/Car/PDMS) was chosen as the optimum extraction phase, not only in terms of extraction efficiency, but also for its broader analyte coverage. Optimum extraction temperature was 30°C, while an extraction time of 15min provided the best compromise between extraction efficiencies of lower and higher molecular weight compounds. The optimized protocol was demonstrated to be capable of sampling plant material with high reproducibility, considering that most classes of analytes met the 20% RSD FDA criterion. The optimized method was employed for the analysis of three classes of M. splendens samples, generating a final list of 65 tentatively identified VOC, including alcohols, aldehydes, esters, ketones, phenol derivatives, as well as mono and sesquiterpenes. Significant differences were evident amongst the volatile profiles obtained from non-galled leaves (NGL) and leaf-folding galls (LFG) of M. splendens. Several differences pertaining to amounts of alcohols and aldehydes were detected between samples, particularly regarding quantities of green leaf volatiles (GLV). Alcohols represented about 14% of compounds detected in gall samples, whereas in non-galled samples, alcohol content was below 5%. Phenolic derived compounds were virtually absent in reference samples, while in non-galled leaves and galls their content ranged around 0.2% and 0.4%, respectively. Likewise, methyl salicylate, a well-known signal of plant distress, amounted for 1.2% of the sample content of galls, whereas it was only present in trace levels in reference samples. Chemometric analysis based on Heatmap associated with Hierarchical Cluster Analysis (HCA) and Principal Component Analysis (PCA) provided a suitable tool to differentiate VOC profiles in vegetal material, and could open new perspectives and opportunities in agricultural and ecological studies for the detection and identification of herbivore-induced plant VOC emissions.

Biogeographical gradients in galling species richness : Tests of hypotheses.

Five hypotheses were invoked to account for variation in galling species number per location on plants of different structural complexity, namely herbs, shrubs, and trees, both in Brazil and USA. The hypotheses were: 1) the altitudinal/latitudinal gradient hypothesis; 2) the harsh environment hypothesis; 3) the plant species richness hypothesis; 4) the host plant area hypothesis; 5) the plant structural complexity hypothesis. The altitudinal and the harsh environment hypotheses were correlated and supported with sample data in both localities, with increasing gall species number as altitude/latitude declined and as sites became hotter and drier. The two hypotheses were separated by studying riparian sites and dry hillside sites at the same elevation in Arizona. Galling species frequency was higher in dry sites than in riparian sites, supporting the harsh environment hypothesis. Of the five hypotheses tested only the harsh environment hypothesis predicted that galling insect species number should vary in response to environmental variables such as moisture and temperature. Temperate shrubs supported more galling species than did other plant types, both in dry and mesic sites. The overall difference between galling species richness for tropical and temperate latitudes was not statistically significant. Free-feeding insect herbivore species exhibited the opposite pattern of species richness to gallers, being more speciose in riparian sites. The present study corroborates the hypothesis that the gall forming habit is an adaptation to harsh or stressful environments, and we describe for the first time broad scale geographical patterns in galling insect species richness.

The adaptive significance of insect gall distribution: survivorship of species in xeric and mesic habitats.

We studied the relationship between habitat moisture and gall-forming insect populations. Population sizes for most galling taxa were significantly larger in xeric habitats compared with mesic habitats. Our results indicate that the differential abundance of galling insects in these habitats is due primarily to differential mortality and survivorship. Mortality factors acting upon eight insect galling species (belonging to eight genera and four families) were measured on six species (five genera and five families) of host plants. Survival was significantly higher for galling populations inhabiting xeric habitats compared with mesic habitats. Parasitism was higher in mesic habitats in seven of eight habitats and fungus-induced diseases were higher in five of seven habitats. Mortality due to predation and other (unknown) factors showed no clear trends. Overall, there was a tendency towards lower mortality and consequently higher survival for populations inhabiting xeric habitats. We hypothesize that reduced mortality caused by natural enemies and endophytic fungi has contributed to the speciation and radiation of galling insects in apparently harsh environments.

The mechanism of plant gall induction by insects: revealing clues, facts, and consequences in a cross-kingdom complex interaction

Galls are defined as modifications of the normal developmental design of plants, produced by a specific reaction to the presence and activity of a foreign organism. Although different organisms have the ability to induce galls in plants, insect-induced galls are the most elaborate and diverse. Some hypotheses have been proposed to explain the induction mechanism of plant galls by insects. The most general hypothesis suggests that gall formation is triggered by the action of chemical substances secreted by the gall inducer, including plant growth regulators such as auxins, cytokinins, indole-3-acetic acid (IAA), and other types of compounds. However, the mode of action of these chemical substances and the general mechanism by which the insect could control and manipulate plant development and physiology is still not known. Moreover, resulting from the complexity of the induction process and development of insect galls, the chemical hypothesis is very unlikely a complete explanation of the mechanism of induction and morphogenesis of these structures. Previous and new highlights of insect gall systems with emphasis on the induction process were analyzed on the basis of the author's integrated point of view to propose a different perspective of gall induction, which is provided in this article. Due to the extraordinary diversity of shapes, colors, and complex structures present in insect galls, they are useful models for studying how form and structure are determined at the molecular level in plant systems. Furthermore, plant galls constitute an important source of material for the study and exploration of new chemical substances of interest to humans, due to their physiological and adaptive characteristics. Considering the finely tuned control of morphogenesis, structural complexity, and biochemical regulation of plant galls induced by insects, it is proposed that an induction mechanism mediated by the insertion of exogenous genetic elements into the genome of plant gall cells could be involved in the formation of this kind of structure through an endosymbiotic bacterium.

Las agallas se definen como modificaciones del diseño y desarrollo normal de las plantas debido a una reacción específica a la presencia y actividad de un organismo foráneo. Aunque diferentes grupos de organismos tienen la habilidad de inducir agallas en plantas, las agallas inducidas por insectos son las más elaboradas y diversas. Algunas hipótesis han sido propuestas para explicar el mecanismo de inducción de las agallas de insectos. La hipótesis más general sugiere que la formación de las agallas es disparada por la acción de sustancias químicas secretadas por el insecto inductor, incluyendo reguladores de plantas como auxinas, citoquininas, ácido-3-indolacético (AIA) o bien otros tipos de compuestos. No obstante, el modo de acción de estas sustancias químicas y el mecanismo general por medio del cual el insecto podría controlar y manipular el desarrollo y fisiología de la planta es aún desconocido. Más aún, como resultado de la complejidad del proceso de inducción y desarrollo de las agallas de plantas inducidas por insectos, la hipótesis química es una explicación insuficiente e incompleta en relación con el mecanismo de inducción y morfogénesis de estas estructuras. Previas y nuevas evidencias relacionadas con el sistema de agallas de insectos, con énfasis en el proceso de inducción, fueron analizadas desde un punto de vista integral del autor para proponer en este artículo una perspectiva diferente sobre la inducción de este tipo de estructuras. Debido a la extraordinaria diversidad de formas, colores y estructuras complejas presentes en las agallas de insectos, las mismas constituyen modelos útiles para estudiar cómo la forma y la estructura son determinadas a nivel molecular en los sistemas vegetales. Además, las agallas de plantas son un importante origen de material para el estudio y exploración de nuevas sustancias químicas de interés humano, debido a las características fisiológicas y adaptativas que presentan. Considerando el control fino del proceso de morfogénesis, regulación bioquímica y complejidad estructural de las agallas de insectos, se propone que un mecanismo de inducción mediado por la inserción de elementos genéticos exógenos dentro del genoma de las células de la planta que forman la agalla podría estar involucrado en la formación de este tipo de estructuras, vía una bacteria endosimbiótica.

The insect gall collection of the Museu Nacional/Universidade Federal do Rio de Janeiro: biome cerrado, rupestrian fields

An inventory of the insect gall from Brazilian savanna (Cerrado) was elaborated based on samples of the collection of the Museu Nacional, Universidade Federal do Rio de Janeiro. Data on localities and host plants were obtained from the labels and information about the gall morphology (plant organ of occurrence, shape, and presence of trichomes) by observing the samples. The galling species was determined based on the literature. The collection includes 131 morphotypes of galls from Cerrado, obtained from 71 host plant species distributed in 50 genera and 30 botanical families (Table 1). All galls were collected in rupestrian fields (a rare vegetation physiognomy of the Brazilian Cerrado) in the state of Minas Gerais. As the collection comprises a great diversity of insect galls, it can be considered representative of this physiognomy.

Um levantamento de galhas de insetos do Cerrado brasileiro foi elaborado baseado em amostras da coleção do Museu Nacional/Universidade Federal do Rio de Janeiro. Dados de localidades e plantas hospedeiras foram obtidos das etiquetas e informações sobre a morfologia da galha (órgão vegetal de ocorrência, forma, e presença de tricomas) pela observação da amostra. As espécies galhadoras foram determinadas baseadas em literatura. A coleção inclui 131 morfotipos de galhas de Cerrado, obtidos de 71 espécies de plantas hospedeiras, distribuídas em 50 gêneros e 30 famílias botânicas (Tabela 1). Todas as galhas foram coletadas em campos rupestres (uma fisionomia vegetal rara do cerrado brasileiro) do Estado de Minas Gerais. Como a coleção compreende grande diversidade de galhas de insetos, pode ser considerada representativa para essa fisionomia.

The insect gall collection of the Museu Nacional/Universidade Federal do Rio de Janeiro: biome cerrado, rupestrian fields / A coleção de galhas de insetos do Museu Nacional/Universidade Federal do Rio de Janeiro: bioma cerrado, campos rupestres

An inventory of the insect gall from Brazilian savanna (Cerrado) was elaborated based on samples of the collection of the Museu Nacional, Universidade Federal do Rio de Janeiro. Data on localities and host plants were obtained from the labels and information about the gall morphology (plant organ of occurrence, shape, and presence of trichomes) by observing the samples. The galling species was determined based on the literature. The collection includes 131 morphotypes of galls from Cerrado, obtained from 71 host plant species distributed in 50 genera and 30 botanical families (Table 1). All galls were collected in rupestrian fields (a rare vegetation physiognomy of the Brazilian Cerrado) in the state of Minas Gerais. As the collection comprises a great diversity of insect galls, it can be considered representative of this physiognomy.

Um levantamento de galhas de insetos do Cerrado brasileiro foi elaborado baseado em amostras da coleção do Museu Nacional/Universidade Federal do Rio de Janeiro. Dados de localidades e plantas hospedeiras foram obtidos das etiquetas e informações sobre a morfologia da galha (órgão vegetal de ocorrência, forma, e presença de tricomas) pela observação da amostra. As espécies galhadoras foram determinadas baseadas em literatura. A coleção inclui 131 morfotipos de galhas de Cerrado, obtidos de 71 espécies de plantas hospedeiras, distribuídas em 50 gêneros e 30 famílias botânicas (Tabela 1). Todas as galhas foram coletadas em campos rupestres (uma fisionomia vegetal rara do cerrado brasileiro) do Estado de Minas Gerais. Como a coleção compreende grande diversidade de galhas de insetos, pode ser considerada representativa para essa fisionomia.

Gall-inducing insects of an Araucaria Forest in southern Brazil

Gall-inducing insects of an Araucaria Forest in southern Brazil. Diversity of galling insects is reported for the first time in an Araucaria Forest site. We address gall characteristics, host plant identification and the inducer identification and provide additional information about sites of gall occurrence in a mosaic of continuous forest and natural forest patches. After 40h of sampling we found 57 species of five insect orders, the majority of them Diptera (Cecidomyiidae), galling 43 host plant species, which in turn belonged to 18 host plant families. Stem and buds together, compared to leaves, harbored more galls, which were mostly glabrous, isolated, fusiform and green. Myrtaceae, Asteraceae and Melastomataceae were the most representative host families. Similarities in gall characteristics to what has been reported in the literature probably result from spatial correlation in a larger scale driven by ecological and evolutionary processes.

Galhas de insetos em restingas da região sudeste do Brasil com novos registros / Insect galls from restingas of Southeastern Brazil, with new records

As restingas da região sudeste do Brasil apresentam 476 morfotipos de galhas de insetos distribuídos em 60 famílias, 131 gêneros e 229 espécies de plantas. As Myrtaceae, Asteraceae e Fabaceae destacam-se por apresentar maior riqueza de galhas e maior número de espécies galhadas. Os gêneros super-hospedeiros são Eugenia (Myrtaceae), Mikania (Asteraceae) e Myrcia (Myrtaceae). As espécies super-hospedeiras são: Guapira opposita (Nyctaginaceae), Mikania cf. biformis (Asteraceae) e seis espécies de Myrtaceae: Eugenia adstringens, Eugenia multiflora, Eugenia copacabanensis, Myrcia fallax, Myrciaria floribunda e Psidium cattleyanum. As galhas ocorrem em todos os órgãos vegetativos e reprodutivos, predominando nas folhas. Os indutores pertencem às ordens Diptera, Lepidoptera, Hemiptera, Coleoptera, Thysanoptera e Hymenoptera. Os Cecidomyiidae (Diptera) destacam-se como o principal grupo galhador e são os únicos insetos a induzir galhas em todos os órgãos vegetais, mostrando uma forte preferência por folhas. Os Lepidoptera representam o segundo grupo galhador mais diversificado em relação ao órgão vegetal atacado, induzindo galhas em folhas, caules, gemas e frutos, com forte preferência por caule. O conhecimento taxonômico das espécies galhadoras ainda é incipiente. Apenas 35% das espécies galhadoras estão identificadas (21% em nível de espécie e 14% em nível de gênero). Os demais registros estão em categorias taxonômicas supragenéricas. Os Cecidomyiidae estão representados por 43 gêneros (cerca de 49% da fauna brasileira desta família) com 156 espécies (84 determinadas e 72 não determinadas), mostrando uma boa representatividade do grupo na região sudeste. Os gêneros mais diversificados são: Clinodiplosis (31 spp.), Neolasioptera (17 spp.), Asphondylia (15 spp.), Lopesia (15 spp.) e Dasineura (13 spp.). Quinze novas ocorrências de galhas são assinaladas para os municípios de Cabo Frio e Paraty (RJ), e uma nova espécie de planta hospedeira é registrada.

The restingas of the Southeastern region of Brazil present 476 morphotypes of insect galls found on 60 families, 131 genera, and 229 plant species. Myrtaceae, Asteraceae, and Fabaceae are the plant families with the greatest richness of galls and number of galled species. The superhost genera are Eugenia (Myrtaceae), Mikania (Asteraceae), and Myrcia (Myrtaceae). The superhost species are Guapira opposita (Nyctaginaceae), Mikania cf. biformis (Asteraceae), and six species of (Myrtaceae); Eugenia adstringens, Eugenia multiflora, Eugenia copacabanensis, Myrcia fallax, Myrciaria floribunda and Psidium cattleyanum. The galls occur on all vegetative and reprodutive plant organs, being more common on leaves. The gallers belong to Diptera, Lepidoptera, Hemiptera, Coleoptera, Thysanoptera, and Hymenoptera. Cecidomyiidae (Diptera) are the most frequent galling insects and the single group that produces galls on all plant organs, showing a strong preference for leaves. Lepidoptera are in the second place and the gallers attack leaves, stems, buds and fruits, with a strong preference for stems. Little is known about the taxonomical knowlegde of galling species (21% are identified at species level and 14% at genus level). The other records are in suprageneric categories. Cecidomyiidae are represented by 43 genera (about 49% of the Brazilian fauna) with 156 species (84 determined and 72 not determined), showing a good representativeness in the Southeastern region of Brazil. The most diversified genera are Clinodiplosis (31 spp.), Neolasioptera (17 spp.), Asphondylia (15 spp.), Lopesia (15 spp.), and Dasineura (13 spp.). Fifteen new gall occurrences are recorded from Cabo Frio and Paraty (RJ), and a new record of host plant is presented.