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Plectris aliena (Coleoptera, Melolonthidae) Chapin is a species already recorded causing serious damage to various cultures in North America and Australia. Although its occurrence has recently been reported in Brazil, information about its distribution, taxonomy, and biology is limited. Thus, this study aims to report this new occurrence of P aliena in Deodápolis (Mato Grosso do Sul, Brazil), as well as to present bioecological and morphological aspects of this species. In this way, the seasonal distribution and the life cycle was studied in the years 2017 and 2018. The larvae were sampled through trenches made in the soil and reared in the laboratory. Adults were captured using "Luiz de Queiroz" light traps. Adults have body with dense white hairs, antennae with 10 antenomeres; they measure approximately 12 mm in length, and their antennal lamellae are larger for males than females. The larvae reach 30 mm in length in the third stage and pupae show about 19 mm in length. The life cycle of this species is univoltine. Due to the great diversity of Plectris and the scarce information available about this species in South America, this study will facilitate its identification in the field and indicate the best time for monitoring in sugarcane crop. [ABSTRACT FROM AUTHOR]

Introduction: Few studies on the effects of rainy/dry cycle and interannual variation in parasites of Amazonian fish have been carried out. We investigated the influence of interannual variation and seasonality on the community structure and infracommunities of parasites in Hemibrycon surinamensis in a tributary of the Amazon River, in northern Brazil. Materials and methods: The fish were examined for the presence of ectoparasites and endoparasites. Results: In 2011, 9 parasite species were found (2 Protozoa, 2 Monogenea, 1 Digenea, 2 Nematoda and 2 Crustacea), and in 2016, 10 parasite species (3 Protozoa, 2 Monogenea, 1 Digenea, 3 Nematoda and 1 Pentastomida). No qualitative or quantitative dissimilarity in the component communities of parasites was observed between 2011 and 2016, but Brillouin Diversity Index, species richness and evenness were higher in 2016, while Berger–Parker dominance was higher in 2011. In both years, Ichthyophthirius multifiliis and Piscinoodinium pillulare were predominated. Some few species of parasites had interannual (P. pillulare and Genarchella genarchella) and seasonal (Trichodina sp., I. multifiliis, P. pillulare and J. hexops) variation patterns. Species richness of parasites was higher in the dry season, but Brillouin diversity, evenness and Berger–Parker dominance were similar between the seasons. Such seasonal variations were due to the host's the availability of infectious stages of parasites with direct life cycle. Conclusions: Variations due to seasonal dry/rainy cycle, which influenced the availability of infective stages of parasites, and host size are the factors causing the changes interannual. [ABSTRACT FROM AUTHOR]

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