Sabrina Celie Oliveira e Silva’s research while affiliated with Montes Claros State University and other places

The diversity of galling insects may be associated with abiotic factors, such as hygrothermal stress, and biotic factors of the host plants, such as structural complexity and resource concentration. In the present study, we aimed evaluate the occurrence of galling insects Palaeomystella oligophaga (Lepidoptera, Agonoxenidae) associated with Macairea radula (Melastomataceae) in veredas of northern of Minas Gerais, testing the effect of environmental stress, resource concentration and plant architecture. The study was carried out in three veredas with distinct levels of soil drying and conservation (preserved, intermediate and degraded). In each vereda, were selected 20 individuals of the Macairea radula for galling sampling. For each focal plants were sampled the abundance of galls, plant height (m), number of branches and number of individuals close to the focal plant within a radius of 5 m. In total, were sampled 2,030 galls of Palaeomystella oligophaga on Macairea radula. The abundance of galls differed significantly between the plants of the different veredas, being higher in the plants of the Vereda da Almescla (intermediate conservation level). In addition, the abundance of galls was positively correlated with plant height, and the number of nearby individuals (considering all plant species). Our results demonstrate that both anthropic alterations that lead to the dryness of the veredas, and structural characteristics of the host plants, can affect the occurrence of galls of Palaeomystella oligophaga.

As abelhas são importantes visitantes florais que necessitam de ambientes bem estruturados com diversidade de recursos para seu forrageamento. A fauna de abelhas vem sofrendo declínio de espécies devido às mudanças antrópicas dos habitats naturais. O estudo objetivou avaliar se a abertura da vegetação natural afeta as comunidades de abelhas em áreas de Floresta Semidecidual do sudeste do Brasil. Nossa hipótese foi que a abertura da vegetação gera um efeito de borda que afeta diferentemente as comunidades de abelhas das tribos Euglossini e Meliponini. Esperávamos que a ocorrência de abelhas Meliponini fosse maior nas áreas próximas à borda, enquanto as abelhas Euglossini fossem mais frequentes em áreas mais distantes da borda. O estudo foi realizado na região central do estado de Minas Gerais, municípios de Ouro Preto, Itabirito e Sabará. Em cada local foi amostrada uma área aberta pela faixa de servidão de uma linha de transmissão onde foram estabelecidos cinco transectos distanciados a 0 m, 50 m e 100 m da área aberta. Registramos 642 indivíduos de 38 espécies de abelhas. As espécies mais abundantes foram Trigona hyalinata (N = 230), Trigona spinipes (N = 108) e Tetragonisca angustula (N = 86). A riqueza e abundância de abelhas foram significativamente maiores nos transectos das áreas abertas (0m), padrão fortemente afetado pelas abelhas Meliponini. No entanto, analisando apenas Euglossini, encontramos maior abundância no transecto mais distante da área aberta. Nossos resultados corroboram a hipótese de que a abertura da vegetação afeta diferentemente as abelhas Euglossini e Meliponini.

Interactions between plants and floral visitors have a significant influence on the structure and function of ecosystems. The study of these interactions can be performed through the analysis of ecological networks, allowing an understanding of the complexity of ecosystem functioning. The objective of the present study was to verify whether the characteristics of individuals of Byrsonima intermedia (Malpighiaceae) affects its role in the network of interactions with floral visitors in Brazilian palm swamps (veredas). Veredas with different levels of dryness were studied, including one degraded vereda (advanced stage of drying), one intermediate vereda (low drying), and one preserved vereda (no drying). For sampling, we selected 45 individuals of the Byrsonima intermedia plant, 15 in each area, where they were monitored to observe the behavior of floral visitor insects and to measure the characteristics of the plant individuals. As a result, the networks of all sampled area were significantly modular and specialized, with the preserved vereda showing greater specialization. In this study, we observed that the networks of individuals of Byrsonima intermedia and their floral visitors were mainly composed of non-oil-collecting bees. The results show that the abundance of resources offered by each individual in the network, the size of the flower and the plant height are some factors that can determine its role in the network of interactions in the studied veredas. Finally, it is concluded that individual plant interactions can be affected both by environmental characteristics and by plant morphological attributes.

We investigated the distribution patterns of galling insects in veredas with varying degrees of drying in the Brazilian Cerrado. We tested if the insect gall diversity is higher in degraded veredas (dry veredas ) compared to preserved (wet veredas ) ones, as predicted by the hygrothermal stress hypothesis. Additionally, we also tested whether the composition of galling insects varied along the veredas and if species richness and abundance of galling insects are higher in the upstream zone of the veredas . In total, we recorded 99 species of galling insects, distributed across 54 plant species and 24 botanical families. We found that galling species richness was high in degraded veredas compared to preserved ones, while the abundance of galling insects was higher in preserved veredas than in degraded ones. When examining the different zones along the veredas , we observed variations in the richness and abundance of galling insects in preserved veredas . Specifically, the galling insect richness was higher in the upstream and middle zones compared to the downstream zone, while the abundance of galling insects was higher in the middle zone compared to the upstream zone. However, in the degraded veredas , there were no significant differences in galling species richness and abundance among the zones studied. The composition of galling insect species differed significantly between degraded and preserved veredas , with a higher faunal similarity observed in preserved veredas for both the downstream and upstream zones compared to degraded vereda s (upstream zone). Our results indicate a preference of galling insects for more hygrothermally stressed environments, such as dry veredas and upstream zones of wet veredas.