RESUMEN
Over the past few years, insects have been used as samplers of vertebrate diversity by assessing the ingested-derived DNA (iDNA), and dung beetles have been shown to be a good mammal sampler given their broad feeding preference, wide distribution and easy sampling. Here, we tested and optimized the use of iDNA from dung beetles to assess the mammal community by evaluating if some biological and methodological aspects affect the use of dung beetles as mammal species samplers. We collected 403 dung beetles from 60 pitfall traps. iDNA from each dung beetle was sequenced by metabarcoding using two mini-barcodes (12SrRNA and 16SrRNA). We assessed whether dung beetles with different traits related to feeding, nesting and body size differed in the number of mammal species found in their iDNA. We also tested differences among four killing solutions in preserving the iDNA and compared the effectiveness of each mini barcode to recover mammals. We identified a total of 50 mammal OTUs (operational taxonomic unit), including terrestrial and arboreal species from 10 different orders. We found that at least one mammal-matching sequence was obtained from 70% of the dung beetle specimens. The number of mammal OTUs obtained did not vary with dung beetle traits as well as between the killing solutions. The 16SrRNA mini-barcode recovered a higher number of mammal OTUs than 12SrRNA, although both sets were partly non-overlapping. Thus, the complete mammal diversity may not be achieved by using only one of them. This study refines the methodology for routine assessment of tropical mammal communities via dung beetle 'samplers' and its universal applicability independently of the species traits of local beetle communities.
Asunto(s)
Escarabajos , Código de Barras del ADN Taxonómico , Mamíferos , Animales , Escarabajos/genética , Escarabajos/clasificación , Mamíferos/genética , Mamíferos/clasificación , Código de Barras del ADN Taxonómico/métodos , ARN Ribosómico 16S/genética , ARN Ribosómico/genética , Análisis de Secuencia de ADN/métodos , Biodiversidad , Metagenómica/métodos , ADN/genética , Heces/químicaRESUMEN
Background: The Amazon Forest is one of the world's most biodiverse ecosystems and yet its protected areas are understudied concerning insects and other invertebrates. These organisms are essential for tropical forests due to their ecological processes, with some species being very sensitive to habitat disturbances. Dung beetles (Coleoptera, Scarabaeidae, Scarabaeinae) have been used as bioindicators for more than 30 years and were surveyed to assess the insect biodiversity of two sustainable-use forest reserves in the Brazilian Amazon. New information: We report inventories of dung beetles from two Amazonian forest reserves in Pará State, Brazil: the Tapajós National Forest and the Carajás National Forest. Surveys were carried out with baited-pitfall traps installed in 2010, 2016, 2017 and 2019. We collected a total of 3,772 individuals from 19 genera and 96 species. We highlight the importance of Amazonian protected areas as refugia for insect biodiversity, particularly dung beetles, which contribute to many key ecosystem processes.
RESUMEN
Abstract The Pantanal is the largest seasonal freshwater wetland on Earth, characterized by the seasonal flooding and complex mosaic vegetation, which determines its biodiversity. Among this biodiversity, dung beetles (Coleoptera: Scarabaeidae: Scarabaeinae) are a group of insects that perform important ecological functions, such as: nutrient cycling, seed dispersion and parasite control. In order to mitigate the lack of information on dung beetle fauna of the Brazilian Pantanal, we conducted a bibliographic search of virtually all literature published until november-2020 on dung beetles sampled in the Pantanal. In addition, we had accessed to the records the largest collection of the dung beetle species from Brazilian Pantanal. We recorded 68 dung beetle species of 30 genera. The genera Canthon Holffmanseg 1847 is the most diverse with 13 species recorded. Although our knowledge about the dung beetle fauna in this ecosystem is still incipient, our results demonstrated a high richness of dung beetles in the Brazilian Pantanal. In addition, our study provides first list of dung beetle species and an illustrated dichotomy key to identify genera and some species occurring in the Brazilian Pantanal. Thus, the use of this guide for identification of dung beetle species and a list of species can be important tools to help researchers and provide incentive for new inventories on dung beetle fauna in the Brazilian Pantanal.
Resumo O Pantanal é a maior área úmida sazonal de água doce Neotropical da Terra, caracterizada pelas inundações sazonais e pela complexa vegetação em mosaico, que determina sua biodiversidade. Dentre essa biodiversidade, os besouros rola-bosta (Coleoptera: Scarabaeidae: Scarabaeinae) são um grupo de insetos que desempenham importantes funções ecológicas, tais como: ciclagem de nutrientes, dispersão de sementes e controle de parasitas. A fim de mitigar a falta de informações sobre a fauna de besouros rola-bosta do Pantanal brasileiro, realizamos uma pesquisa bibliográfica de praticamente toda a literatura publicada até novembro de 2020 sobre besouros rola-bosta amostrados no Pantanal. Além disso, acessamos os registros da maior coleção da espécie de rola-bosta do Pantanal brasileiro. Registramos 68 espécies de besouros rola-bosta de 30 gêneros. O gênero Canthon Holffmanseg 1847 é o mais diverso com 13 espécies registradas. Embora nosso conhecimento sobre a fauna de rola-bostas neste ecossistema ainda seja incipiente, nossos resultados demonstraram uma alta riqueza de besouros rola-bosta no Pantanal brasileiro. Além disso, nosso estudo fornece a primeira lista de espécies de besouros rola-bosta e uma chave de dicotomia ilustrada para identificar gêneros e algumas espécies encontrados no Pantanal brasileiro. Assim, a utilização deste guia para identificação das espécies de besouros rola-bostas e uma lista de espécies podem ser ferramentas importantes para auxiliar pesquisadores e incentivar novos inventários sobre a fauna de besouros rola-bostas no Pantanal brasileiro.