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Abstract Pasturelands are characterized as grasslands utilized for cattle raising and consist of natural or exotic vegetation, predominantly grasses. In the context of sustainable production, the biodiversity of insects within grazing environments holds significant value. Dung beetles play a crucial role in sustaining pasturelands as the burial of feces by these beetles fosters ecological services indispensable for maintaining a robust and healthy environment. Given that different dung beetle species contribute to distinct environmental benefits, a comprehensive understanding of the species present in pasturelands, their origins, and the ecological services they provide is imperative. This study endeavors to compile comprehensive information on dung beetle species native to South America, emphasizing taxonomic precision and a confirmed affinity for cattle dung. Our findings are derived from a synthesis of literature and observational data, incorporating location information obtained from taxonomic revisions and specimen labels of specimens housed at CEMT. In South America, a total of 57 dung beetle species are documented that inhabit grazing areas and actively feed on cattle manure. These areas span diverse biomes encompassing native and/or introduced grasslands, which may include deforested sections within forest biomes such as Chaco, Pantanal, Cerrado, Caatinga, Pampa, Atlantic Forest, Amazon Forest, Paramo, Puna, Llanos, and Patagonia. The preponderance of species identified fall within the paracoprid category, recognized as particularly vital for the sustainability of pasturelands. Despite their acknowledged importance, a noticeable knowledge gap impedes the effective conservation of these species. This gap is a focal point of discussion in this study, addressing the challenges and opportunities for enhancing conservation efforts. The species documented in this research exhibit notable economic and environmental relevance in the context of sustainable livestock production, emphasizing the urgency and significance of initiatives that prioritize their conservation.

Resumo Pastagens são áreas formadas por vegetação nativa ou exótica, principalmente gramíneas, e são utilizadas na pecuária. A diversidade de insetos em áreas de pastagens é muito valiosa, especialmente quando consideramos os métodos de produção sustentável. Besouros rola-bostas são importantes para a sustentabilidade em pastagens porque o enterrio de esterco promove benefícios essenciais para a manutenção do ambiente pastoril. Espécies diferentes exercem diferentes serviços ecossistêmicos, logo é necessário saber quais espécies estão presentes em áreas de pastoreio para saber quais são os benefícios que elas podem proporcionar. Aqui reunimos todas as informações disponíveis para as espécies taxonomicamente bem definidas de rola-bostas nativos da América do Sul e que são conhecidas por utilizar fezes bovinas como recurso para alimentação e nidificação. Usamos dados encontrados na literatura, em observações de campo e em etiquetas de espécimes depositados na CEMT. São registradas 57 espécies de rola-bostas nativos da América do Sul que se alimentam e nidificam em fezes bovinas, e estas estão distribuídas nos seguintes biomas: Chaco, Pantanal, Cerrado, Caatinga, Pampa, áreas abertas da Mata Atlântica e da Floresta Amazônia, Paramo, Puna, Llanos e Patagônia. A maioria das espécies são de paracoprídeos e estes são considerados os mais importantes para as áreas de pastagem. No entanto, existe uma grande lacuna de conhecimento em história natural, o que dificulta a efetividade da conservação dessas espécies. Todas as espécies listadas neste trabalho têm potencial relevância econômica e ambiental na pecuária sustentável e, portanto, o estudo e conservação delas devem ser priorizadas.

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Background: Efforts to alleviate the negative effects of oil spills in the Ecuadorian Amazon include remediation activities such as cleaning, reshaping, and revegetation of polluted areas. However, studies of the diversity of biological communities in these hydrocarbon-degraded ecosystems have never been carried out. Here, we evaluated the diversity of dung beetles on remediated soil ecosystems (Agricultural Soils and Sensitive Ecosystems) and on non-contaminated soils (Natural Forests and Palm Plantations). Methodology: The study was conducted in Sucumbíos and Orellana provinces, in the Ecuadorian Amazon at four sampling sites per ecosystem type (a total of 16 sites). At each sampling site, six pitfall traps remained active for 120 consecutive h per month for 1 year. Results: We collected 37 species and 7,506 individuals of dung beetles. We observed significant differences in mean species abundance, richness, and diversity between non-contaminated soil ecosystems and remediated soil ecosystems, with Natural Forests presenting the highest values, and Agricultural Soils the lowest values. Regarding sampling month, we also found significant differences among ecosystems, which were also higher in Natural Forests. Discussion: The results suggest that hydrocarbon-degraded ecosystems tend to conserve lower beetle diversity one year after remediation highlighting the importance of Natural Forests for the conservation of tropical biodiversity. Therefore, dung beetle diversity could be used for future landscape management of these hydrocarbon-degraded ecosystems.

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The taxonomic revision of the Dichotomius reclinatus species group (Coleoptera: Scarabaeidae: Scarabaeinae: Dichotomius Hope, 1838) sensu Arias-Buriticá and Vaz-de-Mello (2019) is presented. The group comprises four species previously included in the Dichotomius buqueti species group: Dichotomius horridus (Felsche, 1911) from Brazil, French Guiana, and Suriname; Dichotomius nimuendaju (Luederwaldt, 1925) from Bolivia, Brazil, and Peru; Dichotomius quadrinodosus (Felsche, 1901) from Brazil; and Dichotomius reclinatus (Felsche, 1901) from Colombia and Ecuador. A definition of the D. reclinatus species group and an identification key are presented. In the key we included to Dichotomius camposeabrai Martínez, 1974, this species due the external morphology can be confused with the D. reclinatus species group and for the first time photographs of males and female of this species are presented. For each species of the D. reclinatus species group, the following information is provided: taxonomic history, citation of the species in published literature, redescription, list of material examined, photographs of the external morphology, illustrations of male genital organs and the endophallites, and distribution map.

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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.

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Coprophanaeus lancifer is a copro-necrophagous beetle endemic to the Amazon region. Although beetles belonging to the subfamily Scarabaeinae primarily feed on dung, some have a greater diet plasticity that includes carrion, fungi, rotten fruits and invertebrates. The diet of the scavenger beetle C. lancifer mainly consists of vertebrate carcasses, although it is also attracted to mammal faeces. Here, we describe the first record of this species feeding on fruits of the genus Nectandra.(AU)

Coprophanaeus lancifer es un escarabajo copro-necrófago endémico de la región amazónica. Aunque los escarabajos pertenecientes a la subfamilia Scarabaeinae se alimentan principalmente de excrementos, algunos tienen una mayor plasticidad dietética que incluye carroña, hongos, frutas podridas y invertebrados. La dieta del escarabajo carroñero C. lancifer consiste principalmente en cadáveres de vertebrados, aunque, también se siente atraído por heces de mamíferos. Aquí, describimos el primer registro de esta especie alimentándose de frutos del género Nectandra.(AU)

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ABSTRACT Temperature affects the body size of animals, which is an important trait in natural and sexual selection. Insects do not have complex mechanisms of temperature control, thus temperature changes affect their life aspects, from enzymatic reactions to behavior. The amount of fat stored by insects is also influenced by temperature and constitutes a tissue with biosynthetic and metabolic activity, acting as an energy reservoir. We assessed the effect of environmental temperature due to elevation and seasonal temperature variations on body size and condition of two dung beetles species: Canthon rutilans cyanescens and Dichotomius sericeus (Coleoptera: Scarabaeinae). Both species are abundant in southern Brazilian forests, but they differ in habits: the first is a diurnal roller whereas the later is a nocturnal tunneler. Summer months and sites with lower elevations and higher temperatures presented larger C. rutilans cyanescens. A linear relationship exists between body size and soil temperatures, whereas the temperature positively influences the body length. Furthermore, C. rutilans cyanescens from cooler sites had more body fat. Individuals of D. sericeus were also larger in summer months, however, we did not find differences in the proportion of fat or a relation between body size and temperature. Thus, the body size of dung beetle species varies in relation to temporal factors, as both species are larger in summer. More interesting was to observe that the species with a diurnal habit, even though smaller in colder places, has a higher proportion of fat, which indicates an evolutionary response to environmental pressure.

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Sexual selection influences the expression of secondary sexual traits, which are costly to produce and maintain and are thus considered honest indicators of individual condition. Therefore, sexual selection could select for high-quality individuals able to respond to stressful conditions, with impacts on population-level fitness. We sampled dung beetles from 19 pastures and investigated if contamination by herbicides and veterinary drugs modifies male investment in sexually selected traits and has associated population-level effects. We measured horn size, condition dependence (i.e. size-corrected body mass) and allometry, besides abundance and sexual size dimorphism in three species: Copris incertus, Euoniticellus intermedius and Digitonthophagus gazella. In contrary to our expectations, horn size was independent of contamination and individual condition. However, strong positive allometric relationships were reduced by herbicide contamination for C. incertus and D. gazella and were increased by ivermectin for C. incertus, revealing differential investment in horn production according to body size in contaminated habitats. At the population level, large-horned C. incertus males were more abundant in contaminated pastures, potentially revealing a case of evolutionary rescue by sexual selection or a plastic response to higher population densities. Finally, chemical compounds affected the sexual size dimorphism of all three species, with potential effects on female fecundity or intrasexual selection. Together, our findings indicate that contamination interferes with sexual selection processes in the wild, opening new questions regarding the role of sexual selection in favouring species persistence in contaminated environments.

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While theory suggests that at conception the sex ratio should be balanced (1:1), this can be variable across space and time in wild populations. Currently, studies of the environmental factors that regulate adult sex ratio (ASR) in species with different life history traits are scarce. Using capture-recapture over a year, we analyzed the influence of habitat type (forest and nonforest) and season (rainy and dry) on variation in ASR, male aggregation and the trajectory movement of 2 dung beetle species with different life history traits: Deltochilum mexicanum (a hornless roller species) and Dichotomius satanas (a tunneler species with horns on its head and thorax). We found opposite tendencies. The D. mexicanum population tends to be female-biased, but the population of D. satanas tends to be predominantly male, and observed values were not related to habitat type or season. However, the 95% confidence intervals estimated were highly variable between seasons depending on habitat. On examining the monthly variation in ASR for both habitats, we found that it depends on the species. In addition, male aggregation differed between species depending on habitat type and season, and species movement patterns were closely related to their habitat preferences. Based on our results, we argue that comparative population studies of species with different life history traits are necessary to understand the variation in demographic parameters as well as its ecological and evolutionary implications in the face of spatial and climatic environmental variation.

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The Onthophagus mexicanus species group includes at least 18 species: O. anewtoni Howden and Génier, O. arnetti Howden and Cartwright, O. browni Howden, O. cartwrighti Howden, O. championi Bates, O. concinnus Castelnau, O. cynomysi Brown, O. eulophus Bates, O. guatemalensis Bates, O. hecate (Panzer), O. mcclevei Howden and Génier, O. medorensis Brown, O. mexicanus Bates, O. orpheus (Panzer), O. polyphemi Hubbard, O. pseudoguatemalensis sp. n., O. totonacus sp. n. and O. velutinus Howden and Cartwright. Onthophagus pseudoguatemalensis sp. n. and O. totonacus sp. n. are described from Mexico (Jalisco and Veracruz, respectively). Onthophagus cartwrighti, O. championi, O. eulophus and O. guatemalensis are redescribed, while lectotypes are designated herein for O. championi and O. eulophus. The distribution of O. cartwrighti is clarified; a new country record is provided for O. championi (Honduras); new state records are reported for O. championi (Oaxaca and Veracruz, Mexico) and O. guatemalensis (Oaxaca, Mexico). The accurate distribution of O. eulophus remains unknown since its original description. Updated distribution maps are included for all the species within the group. An updated determination key to species of the O. mexicanus species group is provided. The rarity of O. eulophus and O. totonacus in the entomological collections is thought to be a consequence of their trophic habits; both species are suggested to be inquilines of rodent nests or burrows.

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This study evaluated the effects of land-use change (L-UCH) on dung beetle community structure (Scarabaeinae) in a disturbed dry ecosystem in southern Ecuador. Five different L-UCH classes were analyzed by capturing the dung beetle species at each site using 120 pitfall traps in total. To determine dung beetle abundance and diversity at each L-UCH, a general linear model (GLM) and a redundancy analysis (RDA) were applied, which correlated environmental and edaphic conditions to the community structure. Furthermore, changes in dung-producing vertebrate fauna were examined, which varied significantly between the different L-UCH classes due to the specific anthropogenic use or level of ecosystem disturbance. The results indicated that soil organic matter, pH, potassium, and phosphorus (RDA: component 1), as well as temperature and altitude (RDA: component 2) significantly affect the abundance of beetles (GLM: p value < 0.001), besides the food availability (dung). The highest abundance and diversity (Simpson's index > 0.4, Shannon-Wiener index > 1.10) was found in highly disturbed sites, where soils were generally more compacted, but with a greater food supply due to the introduced farm animals. At highly disturbed sites, the species Canthon balteatus, Dichotomius problematicus, and Onthphagus confuses were found specifically, which makes them useful as bio-indicators for disturbed dry forest ecosystems in southern Ecuador.

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The preservation of tropical forests is increasingly at risk, including forests located within human-modified landscapes that retain high conservation value. People modify and interact with these landscapes through a wide range of uses. However, our knowledge of how different forest uses affect biodiversity is limited. Here, we analyse the responses of different taxa to four distinct categories of forest management, namely old-growth forest, Brazil nut extraction areas, reduced impact logging areas, and eucalyptus plantations. Within six independent replicates of each category, we sampled three taxa (fruit-feeding butterflies, dung beetles, and trees) in eastern Amazonia. Forests under moderate use (Brazil nut extraction and reduced-impact logging) had similar, albeit slightly lower, diversity levels relative to old-growth forests, while communities in plantations were significantly less diverse. Only 4%, 20%, and 17%, of the sampled butterfly, dung beetle, and tree species, respectively, were restricted to old-growth forests. This study provides further empirical evidence of the importance of old-growth forest conservation in the context of human-modified landscapes. It also suggests that landscape matrices integrating forest uses at varying intensities are well positioned to reconcile biodiversity conservation with the production of goods that support local livelihoods.

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BACKGROUND: Anthropized landscapes play a crucial role in biodiversity conservation, as they encompass about 90% of the remaining tropical forest. Effective conservation strategies require a deep understanding of how anthropic disturbances determine diversity patterns across these landscapes. Here, we evaluated how attributes and assembly mechanisms of dung beetle communities vary across the Selva El Ocote Biosphere Reserve (REBISO) landscape. METHODS: Community attributes (species diversity, abundance, and biomass) were assessed at the landscape scale, using spatial windows and vegetation classes. Windows were categorized as intact, variegated, or fragmented based on their percent cover of tropical forest. The vegetation classes analyzed were tropical forest, second-growth forest, and pastures. RESULTS: We collected 15,457 individuals and 55 species. Variegated windows, tropical forests, and second-growth forests showed the highest diversity values, while the lowest values were found in intact windows and pastures. Landscape fragmentation was positively and strongly related to dung beetle diversity and negatively related to their abundance; biomass was positively associated with forest cover. Beta diversity was the primary driver of the high dung beetle diversity in the landscape analyzed. DISCUSSION: The landscape heterogeneity and its biodiversity-friendly matrix facilitate the complementarity of dung beetle assemblages in the Selva El Ocote Biosphere Reserve. Random processes govern beta diversity patterns in intact and variegated windows. Therefore, vegetation cover in the region is sufficient to maintain a continuous flow of dung beetles between forested landscape segments. However, intense anthropic disturbances acted as deterministic environmental filters in fragmented windows and pastures sites, leading to biotic homogenization processes. Our results suggest that increasing habitat variegation in highly fragmented sites is an effective strategy to prevent or buffer homogenization processes in the REBISO landscape.

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New World species of the genus Onthophagus Latreille (Coleoptera: Scarabaeidae: Scarabaeinae) have been classified in different ways, all of them without a phylogenetic framework. For instance, Boucomont (1932) separated them in 13 groups of species, but Zunino Halffter (1988; 1997) only recognize five species groups. Howden Gill (1993) add the O. dicranius Bates and O. mirabilis Bates species groups, and Kohlmann Solís (2001) added the O. gazellinus Bates species group. Also, over the years, groups, complexes, and sets of species have been defined using different criteria not even comparable each other. Two of these groupings are the O. dicranius and O. mirabilis species groups, which were firstly separated from the O. clypeatus Blanchard species group (sensu Zunino Halffter 1981, 1997) by Howden Gill (1993). After, Kohlmann Solís (2001) later merged both groups under the O. dicranius species group. Finally, Génier (2017) gives a conceptual framework for species groups and complexes, thus assigning the status of species complex to the two previous species groups, and integrating them in the O. dicranius species group. Herein, we describe a new species of the O. dicranius species complex, update the species list of this complex, and present a revised key to separate these species.

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In this study, we take the Onthophagus chevrolati species group, likely a monophyletic species group as an example to analyze the processes that led to the biogeographic integration of the Holarctic fauna in the mountains of the Mexican Transition Zone to test our biogeographic hypotheses. We propose a change from the status of subspecies to species for O. oaxacanus Zunino Halffter, 1988 new status; O. howdeni Zunino Halffter, 1988 new status; O. jaliscensis Zunino Halffter, 1988 new status; O. longecarinatus Zunino Halffter, 1988 new status; O. omiltemius Bates, 1889 revised status; and O. retusus Harold, 1869 revised status. Consequently, the O. chevrolati group of species is currently made up of 47 species belonging to four species lines: O. vespertilio, O. hippopotamus, O. cyanellus and O. chevrolati. The diversification of the Onthophagus chevrolati species group in this region resulted from three hypothetical stages of evolution. In the first, the penetration and expansion of the ancestor of the O. chevrolati species group occurred before the Miocene and the Trans-Mexican Volcanic Belt arose. During the second stage, the O. hippopotamus species line expanded and evolved, integrating with the paleogeographic changes and the formation of the Trans-Mexican Volcanic Belt, as a consequence of volcanism during the Miocene-Pliocene. In the third and most recent stage, the O. chevrolati species line used the existing mountain systems and interglacial climate fluctuations of the Pleistocene to expand and diversify. Thus, the mountains of the Mexican Transition Zone are not simply periglacial refugia. The entomofauna of Holarctic origin present in the region evolved while the Earth's geological processes were underway.

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Entre 2017 y 2018 se realizaron muestreos durante cuatro meses en un fragmento de bosque tropical perennifolio de un área natural protegida de Chiapas, México. Se instalaron trampas de caída ubicados a lo largo de un trayecto de aproximadamente 500 m. Las trampas fueron cebadas con individuos recién muertos de Messicobolus magnificus, un milpiés abundante en la reserva durante la temporada lluviosa. Se capturaron 108 individuos de cuatro especies de escarabajos: Canthon vazquezae (92), Deltochilum pseudoparile (13), Coprophanaeus corythus (2) y Ateuchus rodriguezi (1). Únicamente D. pseudoparile ha sido previamente recolectada con carroña de otras especies de milpiés. El uso de este tipo de recurso posiblemente sea una fuente alterna que permite reducir la competencia interespecífica por otros recursos efímeros entre los Scarabaeinae.

Between 2017 and 2018, samplings out for four months in a tropical evergreen forest fragment from a natural protected area of Chiapas, Mexico, were carried. Pitfall traps were installed along a path of about 500 m. The traps were baited with freshly killed individuals of Messicobolus magnificus, an abundant millipede during the rainy season in the reserve. 108 individuals of four beetles' species were captured: Canthon vazquezae (92), Deltochilum pseudoparile (13), Coprophanaeus corythus (2) and Ateuchus rodriguezi (1). Only D. pseudoparile has been previously collected with carcasses from other millipede species. The use of this resource type is possibly an alternative source that reduces interspecific competition among the Scarabaeinae for other ephemeral resources.

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The use of veterinary medical products and herbicides is a common practice in intensified livestock systems. These compounds affect nontarget organisms that perform important ecosystem functions, such as dung beetles. The assessment of body condition allows us to determine how individuals respond to changes in the environment. However, assessments of how contamination associated with cattle farming affects coprophagous insects such as dung beetles have not been conducted in natural systems. In the present study, we evaluated the effect of ivermectin (an antiparasitic drug) and herbicides on the body condition of 3 species of dung beetles collected in the field: Copris incertus, Euoniticellus intermedius, and Digitonthophagus gazella. We recorded 3 condition indicators (body size, lipid mass, and muscle mass) of beetles collected from 19 livestock ranches in northeastern Mexico. In general, the use of ivermectin had adverse effects on C. incertus and E. intermedius whereas the effects were positive for D. gazella. Conversely, the use of herbicides had adverse effects on D. gazella and positive effects on C. incertus. The different effects of ivermectin and herbicides found in males and females show that sex can be important in determining individual responses to environmental contamination. Importantly, we provide the first evidence under natural conditions that native and exotic species of dung beetles are highly sensitive to different types of livestock management, with veterinary medications and herbicides having the ability to alter body condition. Changes in dung beetle condition can reduce the ecosystem services that dung beetles provide in livestock systems. Environ Toxicol Chem 2019;38:2392-2404. © 2019 SETAC.

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Understanding the mechanisms underpinning spatiotemporal diversity patterns of biological communities is a major goal of ecology. We aimed to test two ecological hypotheses: (i) temporal patterns of ß-diversity will mostly be driven by nestedness, with a loss of species from summer to winter, and (ii) nestedness values will correlate with climatic variables instead of turnover values, indicating either a loss of species during winter or a gain of species during summer. We sampled dung beetles using standardized sampling protocols along a year in four Atlantic forest sites: two at the northwest and two at the central region of Rio Grande do Sul state, southern Brazil. We partitioned temporal patterns of ß-diversity into turnover and nestedness in order to investigate if community changes are driven by species substitution or gain/loss across time. Our results highlighted five main findings: (i) dung beetle composition varied more with sites than site geographic position; (ii) there was almost one and a half 'true' dung beetle assemblages regarding the spatial distribution of species weighed by abundance; (iii) we found a positive influence of mean temperature and a negative influence of relative humidity on both species richness and abundance; (iv) both spatial and temporal dissimilarity among sites were dominated by species replacement, while the relative importance of nestedness was higher in temporal than spatial patterns; (v) there was an effect of precipitation and relative humidity on temporal patterns of ß-diversity components, but these effects were site-dependent. Contrary to our expectations, the ß-diversity component of turnover dominated both spatial and temporal patterns in dung beetle dissimilarity among sites and months. Distinct climatic variables affected differently the α-diversity and ß-diversity components of dung beetle assemblages. Partitioning ß-diversity into temporal components is a promising approach to unveil patterns of the community dynamics and to produce insights on mechanisms underlying such patterns.

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In this paper we describe Canthidium quercetorum new species (Coleoptera: Scarabaeidae: Scarabaeinae), a species that inhabits dry oak forest in the Mexican state of Oaxaca, between 2100 and 2300 m above sea level. Photographs and an illustration of the habitus and a distribution map are provided. The unusual distribution and ecology of this species are discussed. An updated key for the genus in Mexico and the United States of America is also presented.

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Ivermectin is a powerful antiparasitic drug commonly used in cattle. Ivermectin residues are excreted in dung, threatening non-target coprophagous fauna such as dung beetles. This can have severe ecological and economic consequences for dung degradation and soil fertility. Even though the negative effects of direct ivermectin exposure on dung-degrading organisms are well known, effects could extend across generations. Here, we tested the effects of paternal or maternal exposure to ivermectin on offspring in the dung beetle Euoniticellus intermedius. This species is a classic study subject in ecotoxicology and sexual selection because males have a cephalic horn that is under intense selection via male-male competition. After confirming a negative effect of ivermectin on the number of emerged beetles, we found trans-generational effects of ivermectin exposure on the horn size of male offspring. Surprisingly however, this trans-generational effect only occurred when only the father was exposed. We detected no trans-generational effects of ivermectin exposure on offspring number, sex ratio or body size. Our results confirm that ivermectin not only has a strong effect on exposed individuals but also in their progeny. Our study opens new questions about the mechanisms responsible for parental effects and their long-term fitness consequences in contaminated habitats.

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β-diversity is a key measure to understand biodiversity patterns across spatial and temporal scales.In this study, two published datasets on dung beetle (Coleoptera: Scarabaeinae) from Brazilian Pampa arere-analyzed aiming to investigate the role of β-diversity process-related components based on compositionandabundance-based approaches for both spatial (grassland-forest ecotone) and temporal (samplings along ayear) scales. Dung beetles were sampled in a grassland-forest ecotone in October 2006 and in a grassland areamonthly during an entire year (December 2006 to November 2007), using baited pitfall traps. β-diversity wasdecomposed into turnover and nestedness-resultant components based on Jaccard dissimilarity coefficient,and also into balanced variation in abundance and abundance gradients based on Bray-Curtis dissimilaritycoefficient. Both environmental (spatial scale) and climatic (temporal scale) differences affected dung beetlessimilarly in terms of species replacement and nestedness patterns, and similarly in terms of variation in abundanceand abundance gradients. For both spatial and temporal approach, the species turnover and the variationin species abundances were higher, while nestedness patterns and abundance gradients were of minorrelative importance.(AU)

A diversidade β é uma medida chave para compreenderos padrões de biodiversidade em escalas espaciais e temporais. Neste estudo, são reanalisados dois conjuntosde dados publicados sobre escarabeíneos (Coleoptera: Scarabaeinae) do Pampa Brasileiro, com o objetivode investigar o papel dos componentes da diversidade β relacionados a processos com base em abordagensbaseadas em composição e abundância, tanto para escala espaciais (ecótono campo-floresta) e temporais(amostragens ao longo de um ano). Os escarabeíneos foram amostrados em um ecótono de campo-florestaem outubro de 2006 e em uma área de campo mensalmente durante um ano inteiro (dezembro de 2006 anovembro de 2007), usando armadilhas de queda iscadas. A diversidade β foi decomposta em seus componentesde turnover e aninhamento com base no coeficiente de dissimilaridade de Jaccard e também em variaçãobalanceada de abundância e gradientes de abundância com base no coeficiente de dissimilaridade de Bray--Curtis. As diferenças ambientais (escala espacial) e climáticas (escala temporal) afetaram os escarabeíneos similarmente em termos de substituição de espécies e padrões de aninhamento, e similarmente em termosde variação de abundância e gradientes de abundância. Tanto para a abordagem espacial quanto temporal, asubstituição das espécies e a variação na abundância das espécies foram maiores, enquanto que os padrões deaninhamento e os gradientes de abundância foram de menor importância relativa.(AU)

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