The Cerrado biome is the second largest in Brazil, but the evolution of the Cerrado during the late Quaternary is not yet fully known. This study identifies paleoenvironmental changes during the last 23 000 years, based on a tropical mountain peatland record, in the Serra do Espinhaço Meridional in central-eastern Brazil. A multi-proxy approach was used that involved palynological analysis, stable isotopes (δ 13 C, δ 15 N), geochemistry, radiocarbon dating and multivariate statistics derived from a peatland core from Rio Preto (Minas Gerais state). The study reveals a very humid and cold climate during the late Pleistocene, with an increase in temperature and decrease in humidity at the Pleistocene-Holocene transition. During this period there was strong instability in the landscape (episodes of erosion). At the beginning of the Holocene there was a reduction in humidity with greater landscape stability. The current sub-humid climatic conditions seem to have been established in the mid-/late Holocene, with periods of landscape instability. Our findings agree with other Cerrado records that contradict previously established hypotheses, such as the Amazonian Refuge and the Pleistocene Arc.

RESUMOO objetivo desse trabalho é fazer uma revisão acerca da biologia e ocorrência geográfica dos grupos botânicos que ocorrem na vegetação dos afloramentos calcários da Serra do Cipó localizada na porção sul da Cadeia do Espinhaço Meridional no estado de Minas Gerais. Foram levantadas informações bibliográficas acerca da distribuição espacial e aspectos biológicos de famílias, gêneros e espécies encontradas em um levantamento florístico realizado na região. Os resultados da pesquisa mostram que boa parte dos grupos taxonômicos ocorrentes nas florestas tropicais secas são muito pouco pesquisados pela ciência ambiental brasileira. Conclui-se que estudos de revisão acerca da biologia desses grupos e principalmente estudos que caracterizem a distribuição geográfica dessas plantas são uma demanda para a pesquisa científica e em muito podem ajudar na criação de planos de ação para conservação de espécies. Palavras chave: Serra do Espinhaço Meridional, flora, conservação, Matas Secas. ABSTRACTThe aim of this paper is to review about the biology and geographical occurrence of botanical groups that occur in the vegetation of limestone outcrops of Serra do Cipo located in the southern portion of the Chain of Southern Espinhaço in Minas Gerais. Bibliographic information about the spatial distribution and biological families, genera and species found in a floristic survey in the region points were raised. The survey results show that most taxa occurring in the dry tropical forests are poorly surveyed by Brazilian environmental science. We conclude that review studies on the biology of these groups and especially studies that characterize the geographic distribution of plants is a demand for scientific research and much can assist in creating action plans for species conservation.

-Podisus nigrispinus is a generalist predator naturally occurring in agricultural and forestry systems that effectively contributes to the population balance of phytophagous insects, especially defoliating caterpillars. Histological changes were evaluated in the salivary glands and midgut of P. nigrispinus caused by ingestion of systemic herbicide isoxaflutole. These predator females were fed with leaves of eucalyptus plants, Tenebrio molitor pupae or water, contaminated or not by herbicide. Salivary glands and midguts were dissected, processed and analyzed under a light microscope. Activity level and cell morphology of the salivary glands and midgut showed differences among insects fed on plants, contaminated water or pupae. The epithelia of the salivary gland and midgut of individuals which had no contact with the herbicide showed homogeneous cytoplasm, nucleus with predominance of decondensed chromatin and evident nucleoli, intense cell activity features. As for the insects in contact with contaminated food, they presented undeveloped nucleus and condensed chromatin. The luminal contents of the salivary glands in the contaminated insects had become more acidophilus than in insects without poisoning, as well as having heterogeneous and granular secretion, being more evident in the bioassay in which the insects fed on contaminated water. There was a marked morphological change in the midgut cells in contaminated insects. High degree of apoptosis, disorganization and secretory vacuoles in the epithelial cytoplasm were observed. The apical portion of the midgut cells proved undeveloped, irregular and partially destroyed. It is concluded that isoxaflutole causes morphological changes in the digestive system of the predator P. nigrispinus.Keywords: biological control, cell apoptosis, digestive system, morphological change, Podisus nigrispinus. RESUMO -Podisus nigrispinus é um predador generalista de ocorrência natural em sistemas agrícolas e florestais que contribui de forma efetiva para o equilíbrio populacional dos insetos fitófagos, principalmente lagartas desfolhadoras. Avaliaram-se alterações histológicas nas glândulas salivares e no intestino médio de P. nigrispinus causadas após ingestão do herbicida sistêmico isoxaflutole. Fêmeas desse predador foram alimentadas com folhas de plantas de eucalipto, pupas de Tenebrio molitor ou água, contaminados ou não pelo herbicida. As glândulas salivares e o intestino médio foram dissecados, processados e analisados em microscópio de luz. O nível de atividade e a morfologia celular das glândulas salivares e do intestino médio apresentaram diferenças conforme a alimentação. Os epitélios da glândula salivar e do intestino médio de indivíduos que não tiveram contato com o herbicida apresentaram o citoplasma homogêneo, núcleos com predomínio de cromatina descondensada e nucléolos evidentes. Já os insetos que tiveram contato com o herbicida apresentaram

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