Gall-inducing insects from Atlantic Forest of Pernambuco, Northeastern Brazil

Insect galls of Atlantic Forest areas of Serra da Bodoquena (MS, Midwestern Brazil)

An inventory of insect galls of Serra da Bodoquena (MS, Midwestern Brazil) was carried out in an area of semideciduous seasonal forest situated in the Califórnia Farm. Three field works were done in August/2011, December/2011 and April/2012, when the local vegetation was examined during 40 hours per expedition. Fifty-eight gall morphotypes were found on 40 host plants, 38 of them native. The host plants are distributed in 18 families. The native plants include eight endemic species in Brazil, which together totaled 14 gall morphotypes. Zanthoxylum L. sp. (Rutaceae), an endemic genus in Brazil, hosts one gall morphotype. The non endemic native plants totaled 26 gall morphotypes. Ten new host plants are recorded for the first time in Brazil. The medium number of gall morphotypes per plant species was 1.45. Salicaceae, Bignoniaceae, and Asteraceae presented the highest number of galled species and the greatest gall richness. Leaves were the most frequent galled plant organ and there was a predominance of globoid galls. Diptera (Cecidomyiidae) were the most frequent gallers, but Hemipteran and Thysanopteran galls were also found. The associated fauna was composed of inquilines (Diptera: Muscomorpha and Cecidomyiidae - Trotteria sp., and Thysanoptera), successors (Psocoptera), and parasitoids (Hymenoptera).

Insect galls and associated fauna in two areas of Cerrado sensu stricto in the State of Bahia, Brazil

This study inventoried and characterized the richness of galling insects based on gall morphotypes and their host plants in two Cerrado sensu stricto areas of Caetité municipality in Bahia State, Brazil, to aid the identification of galling insects and their host plants, as well as to contribute to the knowledge and conservation of local biodiversity. The survey was conducted in the Moita dos Porcos archaeological site and João Barroca Farm site, adopting the random walking methodology for sampling, during 12 months. We recorded 98 gall morphotypes on 42 plant species belonging to 36 genera and 22 families. Leguminosae, Malpighiaceae and Myrtaceae demonstrated the greatest richness of galls, and the Copaifera langsdorffii was the super-host species, with 16 gall morphotypes. Most galls occur on leaves, and may be globoid, glabrous, grouped, and are usually unilocular, and brown. The galling insects identified belonged to Coleoptera, Diptera, Lepidoptera, and Thysanoptera. Eight plant host species and eight gall morphotypes were recorded for the first time in Cerrado areas in Brazil. The areas surveyed demonstrated high richness of gall morphotypes and host plants, evidencing the importance of studying and preserving different areas of the same biome.

Gall midges (Insecta, Diptera, Cecidomyiidae) associated with Clusiaceae in Brazil: richness and distribution

A literature compilation was done to gather information about Cecidomyiidae galls on Clusiaceae in Brazil. Botanical names were verified in the site "Flora do Brasil" as well as data on plant distribution and origin. Two herbaria were visited in order to examine galled specimens of Clusiaceae and retrieve new locality records. Thirteen gall morphotypes have been recorded on three genera (Clusia, Garcinia, and Tovomita) and eight species. Clusia showed the greatest number of galled species. Tovomita brevistaminea is the super host species. Only three gallers, Parazalepidota clusiae, Clusiamyia granulosa and C. nitida, were identified at species level, which highlights how the taxonomy of the gall midges is still poorly known. The examination of galled exsiccates resulted in the expansion of their distribution area. The low gall richness as well as the low number of galled plants on Clusiaceae can be related to the presence of resinous sticky sap and waxy cuticle. The known occurrence of gallers associated with Clusiaceae is restricted to the Atlantic Forest as their host plants. The gallers distribution is less wide than that of the host plants, indicating that their geographic limits can be further extended.

Cecidomyiidae (Diptera, Insecta): richness of species and distribution in Brazil

Abstract: Most Neotropical species of Cecidomyiidae (Diptera) have been described from Brazil, but a list of species with occurrence in the country has never been published. Little is known about their distribution and richness in the Brazilian phytogeographic domains. Additionally, a list of host plant species has never been gathered. The present study aims to fill these knowledge gaps and provides an overview of this family in Brazil. For this, data were obtained mainly from the literature, but also from the Cecidomyiidae collection of Museu Nacional and two herbaria (RB and R). Based on the site "Flora do Brasil 2020", botanical names were updated and plant species origin and distribution were verified. A total of 265 gall midge species have been recorded in Brazil, most from the Atlantic Forest (183), followed by Cerrado (60), and Amazon Forest (29). The other phytogeographic domains shelter from five to ten species. Phytophagous gall midges occur on 128 plant species of 52 families, almost all native, being 43 endemic to Brazil (21 endemic to Atlantic Forest, five to Cerrado, and one to Amazon). Although, the taxonomical knowledge is focused on the Atlantic Forest, each domain has its own fauna composition and these informations can be useful for environmental conservational purposes. About 58% of the Brazilian fauna are known only from the type-locality. In order to fill these gaps, it is necessary and important to collect in uninvestigated areas.

An overview of inventories of gall-inducing insects in Brazil: looking for patterns and identifying knowledge gaps

We compiled published Brazilian gall-inducing insect inventories aiming to understand trends and biases in this field research and to investigate the factors that potentially explain the diversity of gall-inducing insects among different sampling sites. A total of 51 studies with gall-inducing insect inventories were compiled for Brazil, which sampled 151 sites in 88 municipalities, 13 states and five regions. The number of papers published on gall-inducing insects per year has increased over the last 30 years, being Cecidomyiidae (Diptera) the main galling taxon, Fabaceae the main host-plant family and Protium heptaphyllum (Burseraceae) the most important super-host species in these inventories. We found a great bias in the geographical distribution of Brazilian inventories, with the majority of studies in the Southeast region, and Atlantic Forest and Cerrado biomes. The total richness of gall-inducing insects differed significantly among regions and biomes, with higher gall richnesses being recorded in the North region and Amazon biome. However, Brazilian regions and biomes did not vary in richness of gall-inducing insect morphotypes per plant species. According our results, sampling by cecidologists in less studied regions of Brazil is needed, particularly in the North and South regions and subsampled biomes such as the Amazon, Pampas and Pantanal.

Insects galls of Pantanal areas in the State of Mato Grosso do Sul, Brazil: characterization and occurrence

Two Pantanal areas were investigated in Corumbá, Mato Grosso do Sul. The field works were carried out in five trails, in August and December/2011 and April/2012. Seventy-six gall morphotypes were found in 52 host plants, 22 of them were identified at species level and 30 at genus. Fabaceae, Myrtaceae and Sapindaceae were the plant families with the greatest richness of gall. Leaves were the plant organ with the greatest gall richness. Six gall shapes were found - globoid, lenticular, fusiform, cylindrical, conical, and marginal roll. The three first were the most common. Five colors were observed - green, brown, red, yellow, and black. Green and brown predominated. Most were glabrous and one-chambered. These features have been indicated in several Brazilian biomes. Diptera (Cecidomyiidae) were the most frequent gallers. The associated fauna comprised parasitoids (Eulophidae, Braconidae, Eupelmidae, Eurytomidae, Platygastridae, and Pteromalidae), inquilines (Cecidomyiidae: Trotteria Kieffer, 1902, Hymenoptera: Tanaostigmoides Ashmead, 1896, Hemiptera, Lepidoptera and Thysanoptera) and predators (Pseudoscorpionida: Olpiolum medium Beier, 1931, Cecidomyiidae: Lestodiplosini and Hymenoptera: Formicidae). Parasitoids were the most frequent. Multiparatism was observed. Our data represent the first contribution to the knowledge of the associated fauna in the Pantanal.

Insect galls in Rupestrian field and Cerrado stricto sensu vegetation in Caetité, Bahia, Brazil

Abstract: We investigated insect galls in Rupestrian field and Cerrado vegetation in the municipality of Caetité (BA), Brazil, between August/2015 and June/2016. This is the first study of gall diversity in Rupestrian field vegetation in that state. We encountered 48 different morphotypes of galls, distributed among 17 different plant species belonging to 13 genera and 21 host plant families. The greatest gall richness was observed in Cerrado (n=39) as compared to Rupestrian field (n=9) vegetation. The principal botanical families observed with galls were Leguminosae, Malpighiaceae, and Myrtaceae, with 10, 8 and 4 morphotypes, respectively. The genera showing the greatest gall diversity were Copaifera L. (n=6) (Leguminosae-Detarioideae), Croton L. (n=2) (Euphorbiaceae), Mimosa L. (n=2) (Leguminosae-Caesalpinioideae), Byrsonima Rich. ex Kunth (n=2) (Malpighiaceae), and Eugenia L. (n=2) (Myrtaceae). The super-host species was Copaifera sabulicola J.A.S. Costa & L.P. Queiroz (n= 5). Most galls occurred on leaves, being globoid, glabrous, isolated, and unilocular. Most gall-inducing insect species belong to the Cecidomyiidae family, while the associated fauna was represented by Hymenoptera and Lepidoptera. We recorded here for the first time galls on Ocotea velutina (Mart. ex Ness) Rohwer (Lauraceae) and Miconia alborufescens Naudin (Melastomataceae). The results indicate the need for more studies to understand the dynamics of the insect-induced galls in Rupestrian field.

Phenotypic plasticity and similarity among gall morphotypes on a superhost, Baccharis reticularia (Asteraceae)

Understanding factors that modulate plant development is still a challenging task in plant biology. Although research has highlighted the role of abiotic and biotic factors in determining final plant structure, we know little of how these factors combine to produce specific developmental patterns. Here, we studied patterns of cell and tissue organisation in galled and non-galled organs of Baccharis reticularia, a Neotropical shrub that hosts over ten species of galling insects. We employed qualitative and quantitative approaches to understand patterns of growth and differentiation in its four most abundant gall morphotypes. We compared two leaf galls induced by sap-sucking Hemiptera and stem galls induced by a Lepidopteran and a Dipteran, Cecidomyiidae. The hypotheses tested were: (i) the more complex the galls, the more distinct they are from their non-galled host; (ii) galls induced on less plastic host organs, e.g. stems, develop under more morphogenetic constraints and, therefore, should be more similar among themselves than galls induced on more plastic organs. We also evaluated the plant sex preference of gall-inducing insects for oviposition. Simple galls were qualitative and quantitatively more similar to non-galled organs than complex galls, thereby supporting the first hypothesis. Unexpectedly, stem galls had more similarities between them than to their host organ, hence only partially supporting the second hypothesis. Similarity among stem galls may be caused by the restrictive pattern of host stems. The opposite trend was observed for host leaves, which generate either similar or distinct gall morphotypes due to their higher phenotypic plasticity. The Relative Distance of Plasticity Index for non-galled stems and stem galls ranged from 0.02 to 0.42. Our results strongly suggest that both tissue plasticity and gall inducer identity interact to determine plant developmental patterns, and therefore, final gall structure.