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We evaluated the impact of burnt carcasses on the probability of finding Chrysomya albiceps (Wiedemann, 1819) and Lucilia ochricornis (Wiedemann, 1830) (Diptera: Calliphoridae), and the time it took for them to arrive at the experimental carcasss. These species are biological indicators of the postmortem interval (PMI) in forensic scenarios. Using stillborn pig carcasses, this study analysed how different degrees of burning affect the level of attraction and colonisation by these species. Experimental models were subjected to level 2 (CG2) and 4 (CG4) burning according to the Crow-Glassman (CG) scale, ranging from fresh to skeletonization. Generalised Linear Models (GLM) with a Binomial distribution were used to evaluate the influence of decomposition time and experimental treatment on the probability of occurrence of each species. Additionally, survival analyses with the Weibull distribution were used to investigate how long it takes until the arrival of the first fly species in each experimental group. The results indicate that burning affects the probability of occurrence and colonisation time of the studied fly species. Although both species were affected by high degrees of burning, Lucilia ochricornis was more heavily affected than Chrysomya albiceps. This pattern was reflected in the time it took for the first occurrence of each fly species. In both cases, it took longer for flies to arrive at carcasses that had been more severely burnt. In the case of C. albiceps, the longest mean time until a fly was detected (Weibull, α = 79.9 h) happened in the CG4 group, followed by the CG2 group (α = 65.6 h) and the control group (α = 51.5 h). In contrast, for L. ochricornis, the longest mean first occurrence time (α = 85.4 h) was in CG2 group, followed by the Control (α = 49.1 h) and CG4 (α = 54.4 h) groups. This study emphasises the importance of considering whether or not a carcass was burnt and its degree of burning in forensic investigations, given that this variable can influence the accuracy of PMI estimation in crime scenes., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Tabanidae (Diptera), popularly known as horse flies, is an important vector group. This is the first study to ascertain the abundance and diversity of horse flies in horses at the cerrado biome of the state of Tocantins, Brazil. Collecting took place in typical Cerrado, and sampling occurred in the dry and rainy seasons. The horseflies were collected from horses using an entomological net. A total of 249 individuals were collected and spread over 25 species. The prevalent species were Stypommisa aripuana (25.8%) and Catachlorops rufescens (6.4%), in the dry period, and Fidena lissorhina (22.5%), Tabanus occidentalis var. dorsovittatus (10%) and Poeciloderas quadripunctatus (6.4%), in the rainy season. The results suggest that tabanids attack horses throughout the dry and rainy seasons, posing a constant threat to their health in the Cerrado of Tocantins.

Horse fly females (Diptera, Tabanidae) are hematophagous and can vector pathogens that affect livestock. Complexes of cryptic species are common in Tabanidae, as exemplified by some species of Tabanus, including Tabanus triangulum and Tabanus occidentalis, both prevalent in the Southern region of Brazil. In this study, geometric morphometrics were employed to ascertain the wing venation in species identification. It was demonstrated that this tool effectively differentiates T. triangulum from T. occidentalis in the coastal plain of Rio Grande do Sul state, situated within the Pampa biome. The results indicate that T. triangulum and T. occidentalis occupy distinct regions of the morphological space, allowing their precise identification through geometric morphometrics, which is fast, affordable, and easy to implement.