ABSTRACT
ABSTRACT Coleoptera order in Brazil presents 105 families with approximately 28,000 species. The life cycle and diversity of Coleoptera are strongly influenced by climate and vegetation. The objective of this study was to evaluate the seasonality and distribution of Coleoptera families in an area of the Cerrado in the Federal District (DF) of Brazil. The insects were collected monthly, between June 2015 and May 2016, using a light trap activated only in nights with a new moon, in an area of cerrado sensu stricto in Planaltina/DF, Brazil. The data were correlated with climatic variables. A total of 21,100 Coleoptera specimens belonging to 34 families were collected, with Melolonthidae (n = 11,075), Carabidae (n = 2,522), Scarabaeidae (n = 2,506), Bostrichidae (n = 1,196), and Chrysomelidae (n = 1,086) being the most abundant. Coleoptera were significantly more abundant in the first half of the rainy season. There was a significant and positive correlation between the abundance of Coleoptera and the climatic variables temperature and precipitation. The data presented in this study are related to an atypical year under the strong influence of the El Niño phenomenon, which may influence the abundance of Coleoptera. Circular analysis revealed that Coleoptera, and the most abundant families, presented seasonality throughout the year with a grouped distribution at the beginning of the rainy season (October to December). This study demonstrates that the richness and abundance of the Coleoptera order, in the Cerrado, is strongly influenced by the characteristic climatic seasons of the biome.
ABSTRACT
Abstract: The Cerambycidae family (Insecta: Coleoptera) has approximately 38 thousand species. In Brazil, more than 4,300 species and 1,050 genera are registered, and despite the ecological and agricultural importance of this family, no study has yet been done in the Cerrado of the Distrito Federal (Brazil). The objective of this study was to evaluate the richness and abundance of Cerambycidae in the Cerrado area using two types of fruits (banana and pineapple), fermented with sugarcane juice, as bait and to verify whether the richness is influenced by climate variables. The work was carried out in an area of the cerrado sensu stricto at Água Limpa Farm in the Distrito Federal. Beetles were collected weekly using 40 bait traps with two types of fruits that remained in the field for 12 uninterrupted months (November 2013 to October 2014). The traps were installed 1.50 m above the ground level, distributed in four 80 m transects, and spaced 20 m apart. A total of 1,599 individuals, belonging to 13 genera and different 19 species, were collected. The main species were as follows: Oxymerus basalis (Dalman, 1823) representing 78.3%, Retrachydes thoracicus thoracicus (Olivier, 1790) representing 9.9%, and Chydarteres bicolor (Fabricius, 1787) representing 4.5% of the total specimens collected. There was a significant difference in richness and abundance of Cerambycidae among the baits evaluated, with the pineapple bait presenting the highest values. The greatest number of individuals and species occurred soon after the first rains, especially in November. Temporal variation was confirmed through Rayleigh's uniformity test, following the seasonality of the Cerrado, with the greatest number of individuals and species found in the rainy season. Temperature and humidity influenced the richness of cerambycid beetles. This is the first work carried out with pineapple fermented with sugarcane juice as bait to capture Cerambycidae, and this type of bait proved to be efficient for the collection of insects, comparable in efficiency to the synthetic baits that are normally used. All species collected were new distribution records for the Distrito Federal (Brazil).
Resumo: A família Cerambycidae (Insecta: Coleoptera) possui aproximadamente 38 mil espécies. No Brasil são registradas mais de 4.300 espécies e 1.050 gêneros e, apesar da importância ecológica e agrícola desta família, ainda não foram realizados trabalhos no Cerrado do Distrito Federal. O objetivo deste trabalho foi avaliar a riqueza e abundância de Cerambycidae utilizando dois tipos de frutas (banana e abacaxi) fermentadas com caldo de cana em área de cerrado e verificar se a riqueza é influenciada pelas variáveis climáticas. O trabalho foi realizado em uma área de cerrado sensu stricto na Fazenda Água Limpa (FAL) em Brasília, Distrito Federal. A coleta de adultos de Cerambycidae foi realizada semanalmente usando 40 armadilhas iscadas com os dois tipos de frutas que ficaram em campo por 12 meses ininterruptos (novembro de 2013 a outubro de 2014). As armadilhas foram instaladas a 1,50 m do nível do solo, distribuídas em quatro transectos de 80 m e espaçadas 20 m entre si. Foram coletados 1.599 indivíduos, 13 gêneros e 19 espécies. As principais espécies foram Oxymerus basalis (Dalman, 1823) com 78,3% do total de espécimes coletado, Retrachydes thoracicus thoracicus (Olivier, 1790) com 9,9% e Chydarteres bicolor (Fabricius, 1787) com 4,5%. Houve diferença significativa na riqueza e abundância de Cerambycidae entre as iscas avaliadas, sendo a isca de abacaxi a que apresentou os maiores valores. O maior número de indivíduos e de espécies ocorre logo após as primeiras chuvas, principalmente no mês de novembro. A variação temporal foi confirmada através do teste de uniformidade de Rayleigh que acompanha a sazonalidade do Cerrado, com maior número de indivíduos e de espécies na estação chuvosa. A temperatura e umidade são as variáveis climáticas que influenciaram a riqueza de cerambicídeos. Este é o primeiro trabalho realizado com abacaxi fermentado com caldo de cana para captura de Cerambycidae, e este tipo de isca se mostrou eficiente para a coleta dos insetos, podendo ser comparado com as iscas sintéticas que normalmente são utilizadas. Todas as espécies coletadas são novos registros de distribuição para o Distrito Federal.
ABSTRACT
Abstract The order Coleoptera is considered second highest in forensic importance in criminal cases involving violent death, because members of this order increase in richness and abundance as the decomposition process progresses. We present here the first Forensic Entomology (FE) case in Brazil where the carrion beetle, Oxelytrum discicolle (Coleoptera: Silphidae), was used to estimate the minimum post-mortem interval (m-PMI) in a forensic case. A female corpse, at an advanced stage of decomposition, was found on a deserted highway near Brasília/Brazil. The corpse was removed from the site, and insect samples were collected on and inside the corpse at the Forensic Medicine Institute of the Federal Police, following the specific FE protocols. The m-PMI was estimated considering two techniques, the pre-appearance interval (PAI) and the accumulated degree-days (ADD). The development stage of the larvae of O. discicolle allowed investigators to propose that this species was part of an earlier colonization, soon after death, with total length and prothorax width compatible with third instar larvae. Adult females of O. discicolle oviposited on the corpse at least 20 days before it was removed from the site where it was found, thus characterizing the m-PMI. This is the first case in which information on the development of the O. discicolle was used in a criminal investigation in Brazil.