Origin of samples of Cannabis sativa through insect fragments associated with compacted hemp drug in South America

Origin of samples of Cannabis sativa through insect fragments associated with compacted hemp drug in South America. Insects associated with a seizure of Cannabis sativa L. may indicate the origin of the illicit drug. Nevertheless, no work regarding this subject has been previously published for South America. In the present investigation, seven kilograms of vegetal material (C. sativa) were inspected for insect fragments. Three species were identified and used to test the origin of the seizure of cannabis plant material: Euschistus heros (Fabricius, 1794), Thyanta perditor (Fabricius, 1794) (Heteroptera, Pentatomidae), and Cephalotes pusillus (Klug, 1824) (Hymenoptera, Formicidae). These insect species restricted the geographic origin of the drug to the Neotropical region, and their distribution patterns showed an overlap of the State of Mato Grosso (Brazil), Argentina, and Paraguay. Based on this information, two of the three major C. sativa growing areas in South America were excluded: (1) the Colombian territory and (2) northeastern Brazil.

Chrysomya albiceps (Wiedemann) and Hemilucilia segmentaria (Fabricius) (Diptera, Calliphoridae) used to estimate the postmortem interval in a forensic case in Minas Gerais, Brazil

ABSTRACT. Chrysomya albiceps (Wiedemann) and Hemilucilia segmentaria (Fabricius) (Diptera, Calliphoridae) used to estimate the postmortem interval in a forensic case in Minas Gerais, Brazil. The corpse of a man was found in a Brazilian highland savanna (cerrado) in the state of Minas Gerais. Fly larvae were collected at the crime scene and arrived at the laboratory three days afterwards. From the eight pre-pupae, seven adults of Chrysomya albiceps (Wiedemann, 1819) emerged and, from the two larvae, two adults of Hemilucilia segmentaria (Fabricius, 1805) were obtained. As necrophagous insects use corpses as a feeding resource, their development rate can be used as a tool to estimate the postmortem interval. The post-embryonary development stage of the immature collected on the body was estimated as the difference between the total development time and the time required for them to become adults in the lab. The estimated age of the maggots from both species and the minimum postmortem interval were four days. This is the first time that H. segmentaria is used to estimate the postmortem interval in a forensic case.

Chrysomya albiceps (Wiedemann) e Hemilucilia segmentaria (Fabricius) (Diptera, Calliphoridae) utilizadas para estimar o intervalo pós-morte em um caso forense em Minas Gerais, Brasil. O cadáver de um homem foi encontrado em uma área de cerrado no Estado de Minas Gerais. Larvas de moscas foram coletadas na cena do crime e encaminhadas ao laboratório em três dias. Os adultos que emergiram em laboratório foram identificados como Chrysomya albiceps (Wiedemann, 1819) e Hemilucilia segmentaria (Fabricius, 1805). Uma vez que insetos utilizam o cadáver como uma fonte de recurso alimentar, sua taxa de desenvolvimento pode ser empregada como uma ferramenta para estimar o intervalo pós-morte. O estágio de desenvolvimento pós-embrionário dos imaturos coletados no cadáver foi estimado como sendo a diferença entre o tempo total de desenvolvimento e o tempo necessário para a emergência destes adultos em laboratório. A idade estimada dos imaturos das duas espécies, bem como o intervalo pós-morte mínimo, foi de quatro dias. Este é o primeiro relato do uso de Hemilucilia segmentaria para estimar o intervalo pós-morte em um caso forense.