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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]

While fireflies are most renowned for their bioluminescent signals, several species also have been shown to possess UV and blue-induced fluorescence. In a field study, we used a sentinel prey approach to investigate whether this trait might serve as an aposematic function in chemically defended fireflies. We also examined and provide the first detailed description of green and red patterns of blue light-induced fluorescence in the adults and larvae of Ellychnia corrusca (L.) (Coleoptera: Lampyridae). We placed artificial prey models with and without fluorescent markings in a forested area of Belmont, Massachusetts, USA, where they were exposed to natural predators. Clay models were styled to resemble Photinus fireflies, the most common firefly genus in this area, and a close relative of Ellychnia. The field study was conducted from Oct through May in Belmont, Massachusetts; this is the period when adults of the diurnal non-luminescent firefly E. corrusca are overwintering on trees. We observed considerable seasonal variation in attack rates, and marks on the clay models indicated they were attacked by avian, mammal, and arthropod predators. However, no difference was seen between fluorescent and non-fluorescent models in predator attack rates. This suggests that fireflies' fluorescent markings do not serve as an aposematic signal, at least for the predator guild active in New England woodlands. [ABSTRACT FROM AUTHOR]

To determine the causes of the variation in the seasonal dynamics of Harmonia axyridis (Pallas) in Central Europe, numbers of adults and larvae of this invasive species were recorded on trees (Acer, Betula, Tilia) throughout the growing seasons from 2011 to 2016. Each year beetles were collected every two weeks, using a standardized sweeping method. The seasonal dynamics was expressed as plots of abundance (number of individuals per 100 sweeps) against time (Julian day) and these plots (seasonal profiles) were compared in terms of their size (area under the seasonal profile curve), range, timing and height of the mode (maximum abundance). Timing and size of seasonal profiles varied among hostplants, years and sites. Abundance of larvae paralleled aphid occurrence and peak abundance of adults followed that of larvae 10 to 20 days later. Population dynamics before and after the peak were determined by dispersal. Adults arrived at sites before the start of aphid population growth and persisted there long after aphid populations collapsed. The abundance of H. axyridis decreased from 2011 to 2013 and then increased, achieving the previous levels recorded in 2015 and 2016. The variation in seasonal profiles revealed that H. axyridis, in terms of its response to environmental conditions, is a plastic species and this fl exibility is an important factor in its invasive success. [ABSTRACT FROM AUTHOR]