One elephant may sustain 2 million dung beetles in East African savannason any given day.

In East African savannas, in the rainy season, an elephant dung bolus is usually transformed into a flat mat of dung residue within a few hours. We extracted the coprophilous beetles of a dung mat from a 1 kg bolus after a one-night exposure and counted 13,699 specimens, most of them aphodiine dung beetles. This is the largest number of dung beetles per kilogram of mammal dung ever counted. Given that an elephant produces an average of 160 kg of feces per day, we extrapolate that one adult elephant provides food for 2.12 million dung beetles on any given day. The elephant population in the Laikipia-Samburu ecosystem in central Kenya, an elephant-rich environment, can sustain, by sheer extrapolation, 14.3 billion dung beetles in an area of 55,000 km2, which translates to ca. 260,000 dung beetles/km2. The decline or extinction of elephants, at least in East African grasslands, may have a massive cascade effect on the populations of coprophagous beetles and the biota dependent on or gaining an advantage from them.

Taking advantage of opportunistically collected historical occurrence data to detect responses to climate change: The case of temperature and Iberian dung beetles.

This study introduces a novel approach to leverage high-resolution historical climate data and opportunistically collected historical species occurrence data for detecting adaptive responses to global change. We applied this procedure to the temperature data and the most comprehensive Iberian dataset of dung beetle occurrences as an illustrative example. To understand how populations of different species are responding, we devised a procedure that compares the temporal trend of spatial and temperature variables at the locations and times of all the occurrence data collection (overall trend) with the specific temporal trends among the occurrences of each species. The prevalence of various species responses is linked to life history or taxonomic characteristics, enabling the identification of key factors influencing the propensity to experience different effects from climate change. Our findings suggest that nearly half of the Iberian dung beetle species may be adversely affected by temperature increases, with a geographic shift being the most common response. The results generated through the proposed methodology should be regarded as preliminary information, serving to formulate hypotheses about the diverse responses of species to climate change and aiding in the selection of candidate species capable of coping with challenges posed by changing temperatures.

Ecological relationships between coprophagous insects and livestock production: a review.

The ecological function played by the coprophagous insects is an important issue in livestock production contexts. The role of this fauna, specially dung beetles, provides benefits to both rangelands and production performance. This interaction has been studied and reported in many scientific articles, in very different places and with diverse production contexts. However, a comprehensive review of the relationship between coprophagous insects and livestock production is still lacking. We reviewed the research studies on this topic during the past five decades, with a focus in Scarabaeidae taxon and livestock production, in order to identify further research priorities. We analysed 435 research articles. The main results were: (I) studies were mostly located in temperate broadleaf forest biome, whereas arid environments were less studied; (II) Production practices impacts category was the most studied, for which the effects produced by antiparasitic products on the coprophagous insects (n = 93; 21% of total revised articles) was the topics with major number of articles. Followed was Biology category (n = 69; 16%), then in Ecosystem function category the most frequent studies were on dung removal (n = 40; 9%), whereas in the Ecosystem Services category the most frequent studies were on biological control (n = 28; 6%); (III) Australia, Mexico, Brazil, and United States were the countries with most research articles. We identified some knowledge gaps on relevant ecological functions of this fauna, in relation to benefits to livestock production. There is a need for future research on nutrient cycling, bioturbation, effects on primary production and vegetation diversity.

Forest conversion into pasture selects dung beetle traits at different biological scales depending on species pool composition.

The conversion of forests into open areas has large effects on the diversity and structure of native communities. The intensity of these effects may vary between regions, depending on the existence of native species adapted to open habitats in the regional pool or the time since habitat change.We assess the differences in species richness and functional diversity of dung beetle communities (Coleoptera: Scarabaeinae) between native forests and novel pasturelands of the Atlantic Forest and the Cerrado, two biomes with contrasting histories of human occupation in Brazil. We conducted standardized surveys in seven forest fragments and adjacent pastures in each region and measured 14 traits in individuals collected in each type of habitat at each particular site. We calculated functional richness, functional evenness, functional divergence, and community-weighted mean of traits for each area, and analyzed individual variation through nested variance decomposition and Trait Statistics.Communities were richer and more numerous at the Cerrado. We did not find any consistent relationship between functional diversity and forest conversion beyond the changes in species diversity. Although landscape changes were more recent at the Cerrado, the colonization of the new habitat by native species already adapted to open habitats lessens the functional loss in this biome. This indicates that habitat change's effects on trait diversity depend on the regional species pool rather than on time since land conversion.Forest conversion effects were primarily due to internal filtering. The effects of external filtering only appear at the intraspecific variance level, with contrasting differences between the Cerrado, where traits related to relocation behavior and size are selected, and the Atlantic Forest, where selection operates for traits related to relocation behavior and flight. These results evidence the importance of considering individual variance to address the responses of dung beetle communities to forest conversion.

A conversão de florestas em áreas abertas tem grandes efeitos sobre a diversidade e estrutura das comunidades nativas. A intensidade desses efeitos pode variar entre regiões, dependendo da existência de espécies nativas adaptadas a habitats abertos no pool regional ou do tempo de mudança de habitat.Avaliamos as diferenças na riqueza de espécies e diversidade funcional de comunidades de rola­bosta (Coleoptera: Scarabaeinae) entre florestas nativas e pastagens da Mata Atlântica e do Cerrado, dois biomas com histórias contrastantes de ocupação humana no Brasil. As comunidades foram amostradas em sete fragmentos florestais e pastagens adjacentes de cada região. Medimos quatorze caracteres de indivíduos coletados em cada ponto amostral de cada habitat e região. Posteriormente, calculamos a riqueza funcional, a equidade funcional, a divergência funcional e a média dos caracteres ponderada pela comunidade (CWM) para cada ponto amostral e analisamos a variação individual por meio de decomposição de variância aninhada e estatística T.As comunidades do Cerrado foram mais ricas e numerosas. Não encontramos nenhuma relação consistente entre diversidade funcional e conversão florestal além das mudanças na diversidade de espécies. Surpreendentemente, embora as mudanças na paisagem tenham sido mais recentes no Cerrado, a colonização do novo habitat por espécies nativas já adaptadas a habitats abertos diminuiu a perda funcional nos novos habitats deste bioma em comparação com a Mata Atlântica, onde as pastagens foram colonizadas apenas por espécies florestais generalistas e invasores exóticos. Isso indica que os efeitos da mudança de habitat na diversidade de caracteres dependem do conjunto regional de espécies e não do tempo desde a conversão da paisagem.Além disso, os efeitos da conversão florestal foram principalmente devidos à efeitos de filtros internos. Os efeitos de filtros externos apareceram apenas no nível de variância intraespecífica, com diferenças contrastantes entre o Cerrado, onde são selecionados caracteres relacionados ao comportamento de realocação e tamanho (Comprimento da Metatíbia, Comprimento, Volume e Largura do Pronoto) e a Mata Atlântica, onde a seleção opera em caracteres relacionadas ao comportamento de realocação e voo (Metatibia Length e Wing Load). Esses resultados evidenciam a importância de se considerar a variância individual para abordar as respostas das comunidades de rola­bostas à conversão florestal.

A Taxonomic Revision of the Dichotomius reclinatus (Felsche, 1901) Species Group (Coleoptera: Scarabaeidae: Scarabaeinae).

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.

Dung beetles from two sustainable-use protected forests in the Brazilian Amazon.

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.

Effects of habitat loss on three insect assemblages in modified ecosystems of foothills of the Colombian Orinoquia / Efectos de la pérdida de hábitat en tres ensambles de insectos en ecosistemas modificados de Piedemonte en la Orinoquia colombiana

Abstract Introduction: The effects of habitat transformation have been widely studied and the effects are well-known at different levels of biological organization. However, few studies have focused on responses to this process at the level of multiple taxa in diverse taxonomic and functional groups. Objective: Determine the variations in taxonomic and functional diversity of ants, butterflies, and dung beetles, at a spatial and temporal level in a landscape mosaic of the ecoregion of the Colombian foothills. Methods: We assessed amount of natural habitat and landscape composition in four types of vegetation, during the highest and lowest rain periods. We collected butterflies with hand nets and used baited pitfall traps for dung beetles and ants. Results: Habitat loss positively affected ant and butterfly species richness, and negatively affected dung beetles. The abundance of ants and butterflies had a positive effect on the dominance of species in the transformed vegetation, for dung beetles the abundance was negatively affected by the absence of canopy cover. Habitat loss had no negative effect on functional diversity as there is no difference between natural and transformed vegetation. Conclusions: The amount of habitat, habitat connectivity and different types of vegetation cover were important factors in the maintenance of insect diversity in the modified ecosystems of foothills of the Colombian Orinoquia. The lack of a common spatial and temporal pattern shows that studies of multiple insect taxa should be carried out for biodiversity monitoring and conservation processes.

Resumen Introducción: Los efectos de la transformación del hábitat han sido ampliamente estudiados y son bien conocidos los efectos a diferentes niveles de organización biológica. Sin embargo, pocos estudios se han centrado en las respuestas a este proceso a nivel de múltiples taxones en diversos grupos taxonómicos y funcionales. Objetivo: Determinar las variaciones en la diversidad taxonómica y funcional de hormigas, mariposas y escarabajos coprófagos, a nivel espacial y temporal en un mosaico paisajístico de la ecorregión del piedemonte colombiano. Métodos: Evaluamos la cantidad de hábitat natural y la composición del paisaje en cuatro tipos de vegetación, durante los períodos de mayor y menor lluvia. Recolectamos mariposas con redes de mano y usamos trampas de caída con cebo para escarabajos coprófagos y hormigas. Resultados: La pérdida de hábitat afectó positivamente la riqueza de especies de hormigas y mariposas y afectó negativamente a los escarabajos peloteros. La abundancia de hormigas y mariposas tuvo un efecto positivo sobre la dominancia de especies en la vegetación transformada, para los escarabajos coprófagos la abundancia se vio afectada negativamente por la ausencia de cobertura de dosel. La pérdida de hábitat no tuvo un efecto negativo sobre la diversidad funcional ya que no hay diferencia entre la vegetación natural y la transformada. Conclusiones: La cantidad de hábitat, la conectividad del hábitat y los diferentes tipos de cobertura vegetal fueron factores importantes en el mantenimiento de la diversidad de insectos en los ecosistemas modificados del piedemonte de la Orinoquia colombiana. La falta de un patrón espacial y temporal común muestra que se deben realizar estudios de múltiples taxones de insectos para los procesos de monitoreo y conservación de la biodiversidad.

Negative effects of forest gaps on dung removal in a full-factorial experiment.

Ecosystem functioning may directly or indirectly-via change in biodiversity-respond to land use. Dung removal is an important ecosystem function central for the decomposition of mammal faeces, including secondary seed dispersal and improved soil quality. Removal usually increases with dung beetle diversity and biomass. In forests, dung removal can vary with structural variables that are, however, often interrelated, making experiments necessary to understand the role of single variables on ecosystem functions. How gaps and deadwood, two main outcomes of forest management influence dung removal, is unknown. We tested if dung removal responds to gap creation and deadwood provisioning or if treatment effects are mediated via responses of dung beetles. We expected lower removal rates in gaps due to lower dung beetle biomass and diversity. We sampled dung beetles and measured dung removal in a highly-replicated full-factorial forest experiment established at 29 sites in three regions of Germany (treatments: Gap, Gap + Deadwood, Deadwood, Control). All gaps were experimentally created and had a diameter of around 30 m. Dung beetle diversity, biomass and dung removal were each lower in gaps than in controls. Dung removal decreased from 61.9% in controls to 48.5% in gaps, irrespective of whether or not the gap had deadwood. This treatment effect was primarily driven by dung beetle biomass but not diversity. Furthermore, dung removal was reduced to 56.9% in the deadwood treatment. Our findings are not consistent with complementarity effects of different dung beetle species linked to biodiversity-ecosystem functioning relationships that have been shown in several ecosystems. In contrast, identity effects can be pronounced: gaps reduced the abundance of a large-bodied key forest species (Anoplotrupes stercorosus), without compensatory recruitment of open land species. While gaps and deadwood are important for many forest organisms, dung beetles and dung removal respond negatively. Our results exemplify how experiments can contribute to test hypotheses on the interrelation between land use, biodiversity and ecosystem functioning.

Effects of Avermectins on the Environment Based on Its Toxicity to Plants and Soil Invertebrates-a Review.

Avermectins are pharmaceutical drugs widely used mainly in livestock to combat both ectoparasites and endoparasites. Drugs belonging to this family include ivermectin, abamectin, doramectin, selamectin, eprinomectin, and emamectin benzoate, and they share similar chemical characteristics. When administered to livestock, between 80 and 98% of the drug is estimated to leave the body without being metabolized in feces, thus reaching the soil. For this reason, concern for avermectin contamination in soil is increasing, and researchers are focused on estimating the effects on non-target organisms, such as plants and soil invertebrates. This review aimed to compile and discuss updated data of avermectin toxicity on non-target organisms to better comprehend its effect on the environment. Effects on plants are scarcely studied, since they were not believed to absorb these drugs. However, recent studies suggest that plants can be negatively affected. Regarding soil invertebrates, negative effects such as increased mortality and reduced reproduction are best known to dung-beetles. Recently, some studies have also suggested that earthworms, springtails, and enchytraeids can be adversely affected by avermectin exposure. Since ivermectin was the first avermectin marketed, most of the data refers to this product. According to new data on scientific literature, avermectins can now be considered harmful to non-target organisms, and its prudent use is recommended in order to reduce negative effects on the environment. For future investigations, inclusion of avermectins other than ivermectin, as well as field and "omics" studies is suggested.

Presence of pesticides and biocides at Dutch cattle farms participating in bird protection programs and potential impacts on entomofauna.

In spite of meadow bird protection programs, a severe decline of meadow birds is taking place in the Netherlands. It is hypothesized that pesticides and other agrochemicals may contribute to this decline through a negative impact on the entomofauna; a very important food source of meadow birds and especially of their chicks. The present study analysed the presence of 664 pesticides (including biocides and some metabolites) in soil, concentrated feed, manure and some fodder samples from 23 cattle farms in the province of Gelderland (the Netherlands). Furthermore, the presence of 21 anti-parasitic medicines in manure from storage facilities was analysed. For farms practicing field grazing, the number of dung beetles in field samples of fresh manure was determined and a potential relationship with the presence of pesticide residues was explored. Of the 23 farms included in present study, 22 participated in meadow bird protection schemes. A total of 129 different pesticides (including biocides and metabolites) was detected, of which 115 at the 15 conventional farms and 69 at the 8 certified organic farms. The average total amount of pesticide residues detected tended to be lower at organic cattle farms than at conventional farms; for organic concentrated feed this difference was significant at a factor of 3.7. A significant negative correlation was found between the estimated daily intake of insecticides by cattle through the consumption of concentrated feed and hay, and the numbers of dung beetles detected in fresh manure samples in the field. We discuss the most important insecticides detected in concentrated feed and hay, and conclude that their quantities in manure and feed, if compared with LR50 values, give a reason for concern. More research is needed to establish the role of agrochemicals in the decline of meadow birds.

Efectos colaterales del uso de la ivermectina en ganadería: comunidad de las boñigas en Colombia / Side effects of ivermectin use in livestock: dung community in Colombia / Efeitos colaterais do uso de ivermectina na pecuária: comunidade boñigas na Colômbia

Resumen La ivermectina es el antiparasitario más usado en veterinaria a nivel mundial desde que entró al mercado en 1981. La U.S. Food and Drug Administration (FDA) americana en su valoración de riesgos determinó que, si bien es muy tóxica para organismos acuáticos, es improbable que, con las aplicaciones registradas para uso animal y por sus propiedades fisicoquímicas, se lleguen a contaminar cursos de agua. Sin embargo, los efectos de la ivermectina (IVM) sobre la fauna de invertebrados no blanco si pueden tener gran repercusión en la ecología de los pastizales por los costes asociados a la presencia de las boñigas no degradadas. De hecho, las pérdidas económicas por disminuir la calidad de los pastizales y reducir la superficie de los pastos disponible y apetecibles al ganado se han calculado en hasta 380 millones de dólares para la economía americana. La ivermectina afecta a un grupo muy beneficioso y diverso taxonómicamente que habita las boñigas, incluyendo a moscas coprófagas, avispas parasíticas, y escarabajos coprófagos y depredadores. Algunos estudios muestran que las boñigas de animales tratados con IVM pueden permanecer en los pastizales sin muestras apreciables de degradación hasta 340 días, mientras que las de animales no tratados son degradadas casi totalmente después de 80 días. Además, estudios de campo y laboratorio han mostrado que la sensibilidad de muchos insectos ocurre a concentraciones muy por debajo de las que se excretan con las heces de bovinos tratados con IVM. Los efectos sobre la reproducción y desarrollo de larvas de coleópteros ocurren incluso a concentraciones que son de hasta 10 veces por debajo de las que producen mortalidad. En Colombia se han identificado al menos 68 especies de la subfamilia Scarabaeinae que integran la comunidad de las boñigas del bovino. La mayor diversidad de escarabajos estercoleros se ha asociado a bosques y sistemas silvopastoriles que incorporan arboles nativos y proveen hábitats favorables para su supervivencia.

Abstract Ivermectin (IVM) has been the world most widely used antiparasitic agent in veterinary medicine since it came to the market in 1981. The U.S. Food and Drug Administration (FDA) in its risk assessment determined that, although it is very toxic to aquatic organisms, it is unlikely to contaminate water courses from current applications registered for animal use. However, the effects of IVM on non-target invertebrate fauna can have great impact on grassland ecology due to the costs associated with the presence of undegraded dung. In fact, the economic losses from lowering the quality of pastures and reducing the area of pasture available and palatable to livestock have been estimated in $380 million for the American economy. Ivermectin affects a highly beneficial and taxonomically diverse group that inhabits dung, including dung flies, parasitic wasps, and coprophilus and predatory dung beetles. Some studies show that dung from IVM-treated animals can remain in pasture without appreciable signs of degradation for up to 340 days, while those from untreated animals are almost completely degraded after 80 days. In addition, field and laboratory studies have shown the susceptibility of many insects to occur at concentrations well below those excreted in the feces of cattle treated with IVM. Effects on reproduction and development of coleopteran larvae occur at concentrations that can be 10 times lower of those causing mortality. In Colombia, at least 68 species of the subfamily Scarabaeinae have been identified in dung communities. The greater diversity of dung beetles has been associated with forests and silvopastoral systems that incorporate native trees and provide favorable habitats for their survival.

Resumo A ivermectina (IVM) tem sido o agente antiparasitário mais utilizado no mundo na medicina veterinária desde que chegou ao mercado em 1981. A US. Food and Drug Administration (FDA) em sua avaliação de risco determinou que, embora seja muito tóxico para organismos aquáticos, é improvável que contamine cursos d'água a partir de aplicações atuais registradas para uso animal. No entanto, os efeitos do IVM na fauna de invertebrados não-alvo podem ter grande impacto na ecologia das pastagens devido aos custos associados à presença de esterco não degradado. De fato, as perdas econômicas decorrentes da redução da qualidade das pastagens e da redução da área de pastagem disponível e palatável para o gado foram estimadas em US$ 380 milhões para a economia americana. A ivermectina afeta um grupo altamente benéfico e taxonomicamente diverso que habita o esterco, incluindo moscas do esterco, vespas parasitas e coprófilos e escaravelhos predadores. Alguns estudos mostram que o esterco de animais tratados com MIV pode permanecer no pasto sem sinais apreciáveis de degradação por até 340 dias, enquanto os de animais não tratados são quase completamente degradados após 80 dias. Além disso, estudos de campo e de laboratório mostraram que a suscetibilidade de muitos insetos ocorre em concentrações bem abaixo daquelas excretadas nas fezes de bovinos tratados com MIV. Os efeitos sobre a reprodução e desenvolvimento de larvas de coleópteros ocorrem em concentrações que podem ser 10 vezes menores daquelas que causam mortalidade. Na Colômbia, pelo menos 68 espécies da subfamília Scarabaeinae foram identificadas em comunidades de esterco. A maior diversidade de escaravelhos tem sido associada a florestas e sistemas silvipastoris que incorporam árvores nativas e proporcionam habitats favoráveis à sua sobrevivência.

Dung beetle community composition affects dung turnover in subtropical US grasslands.

An important service in many ecosystems is the turnover and degradation of dung deposited by cattle. Dung beetles are the primary group of insects responsible for dung turnover, and factors affecting their abundance and distribution thus impact dung degradation. Lands lost to grazing due to dung buildup and pasture contamination total millions of acres per year in US pastures.We evaluated the structural differences in dung beetle assemblages in natural grasslands versus a managed agroecosystem in subtropical southeastern Florida (USA). We measured the direct effect of dung longevity when dung beetle fauna normally inhabiting dung pats were excluded.Our results indicate dung beetle abundance, functional diversity, and species richness have a substantial impact on the rate of dung turnover in subtropical pastoral lands with ~70% of dung removed from the soil surface after three months. Functional diversity and evenness did not have a significant positive effect on dung removal in managed, versus natural grasslands demonstrating a strong relationship between dung beetle assemblage composition and delivery of a key ecological process, dung degradation.We suggest the importance of trees, which provide a thermal refuge for beetles, should be dispersed within matrixes of open pasture areas and within proximity to adjacent closed-canopy hammocks to facilitate the exchange of dung beetles between habitats and therefore maintain the provisioning of dung degradation services by dung beetle assemblages.

The Dung Beetle Oxyomus of Taiwan (Coleoptera: Scarabaeidae): Review of the Fauna, a New Species and its Larva Associated by DNA Barcoding.

The Taiwanese fauna of the dung beetle genus Oxyomus Dejean, 1833 (Coleoptera: Scarabaeidae: Aphodiinae) is reviewed based on museum specimens and newly collected material. Four species, all endemic to Taiwan, are recognized, one of which is newly described here: O. alligator sp. nov. Remaining species are diagnosed, compared with similar relatives from outside of Taiwan, and their distribution is mapped. We show that Taiwanese Oxyomus species form three distinct morphological groups, similar to species from Japan, SE Asia and Malay Archipelago, respectively, indicating a possible composite origin of Taiwanese fauna. The species occur in submontane and montane forests at altitudes of 700-2550 m including the secondary Cryptomeria ones. Available data confirm their association with dung of various forest mammals (monkeys, muntjacs and serows), although the discovery of larvae in sifted forest leaf litter may indicate they can also develop in nutrient-rich substrate around the dung. The larva of O. alligator sp. nov. is described in detail, based on the larval specimens associated with adults by DNA barcodes. Larvae of Oxyomus alligator sp. nov. are similar to those of the European O. sylvestris (Scopoli, 1763), with important differences only found on maxilla and abdominal apex.

Cold-induced anesthesia impairs path integration memory in dung beetles.

Path integration is a general mechanism used by many animals to maintain an updated record of their position in relation to a set reference point.1-11 To do this, they continually integrate direction and distance information into a memorized home vector. What remains unclear is how this vector is stored, maintained, and utilized for successful navigation. A recent computational model based on the neuronal circuitry of the insect central complex suggests that home vector memories are encoded across a set of putative memory neurons and maintained through ongoing recurrent neural activity.12 To better understand the nature of the home vector memory and experimentally assess underlying mechanisms for maintaining it, we performed a series of experiments on the path integrating dung beetle Scarabaeus galenus.13 We found that, while the directional component of the home vector was maintained for up to 1 h, the distance component of the vector memory decreased gradually over time. Using cold-induced anesthesia, we disrupted the neural activity of beetles that had stored a home vector of known length and direction. This treatment diminished both components of the home vector memory, but by different amounts-the homing beetles lost their distance memory before their directional memory. Together, these findings present new insights into the functional properties of home vector memories and provide the first empirical evidence that a biological process that can be disrupted by cold-induced anesthesia is essential to support homing by path integration.

Extinct before discovered? Epactoidesgiganteus sp. nov. (Coleoptera, Scarabaeidae, Scarabaeinae), the first native dung beetle to Réunion island.

We describe a new species of dung beetle, Epactoidesgiganteus sp. nov., from a single female specimen allegedly collected in the 19th century on Réunion island and recently found at the Muséum national d'Histoire naturelle, Paris. This species differs from other species of Epactoides by larger size and a set of other distinctive morphological characters. Epactoidesgiganteus sp. nov. is the first native dung beetle (Scarabaeinae) of Réunion, and its discovery expands the known area of distribution of the genus Epactoides, which was hitherto believed to be endemic to Madagascar. Like other taxa from Madagascar and peripheral islands (e.g., Comoro, Seychelles, Mascarenes), E.giganteus sp. nov. may have reached Réunion by over-water dispersal. Given the rapid loss of biodiversity on Réunion island and the fact that no additional specimens were re-collected over the last two centuries, it is very likely that E.giganteus sp. nov. has gone extinct. However, we have unconfirmed evidence that the holotype of E.giganteus sp. nov. might be a mislabeled specimen from Madagascar, which would refute the presence of native dung beetles on Réunion. We discuss both hypotheses about the specimen origin and assess the systematic position of E.giganteus sp. nov. by examining most of the described species of Madagascan Epactoides. Additionally, we provide a brief overview of the dung beetle fauna of Mascarene Archipelago.

Novel antimicrobial cecropins derived from O. curvicornis and D. satanas dung beetles.

Antibiotic resistance is an increasing global problem and therapeutic alternatives to traditional antibiotics are needed. Antimicrobial and host defense peptides represent an attractive source for new therapeutic strategies, given their wide range of activities including antimicrobial, antitumoral and immunomodulatory. Insects produce several families of these peptides, including cecropins. Herein, we characterized the sequence, structure, and biological activity of three cecropins called satanin 1, 2, and curvicin, found in the transcriptome of two dung beetle species Dichotomius satanas and Onthophagus curvicornis. Sequence and circular dichroism analyses show that they have typical features of the cecropin family: short length (38-39 amino acids), positive charge, and amphipathic α-helical structure. They are active mainly against Gram-negative bacteria (3.12-12.5 µg/mL), with low toxicity on eukaryotic cells resulting in high therapeutic indexes (TI > 30). Peptides also showed effects on TNFα production in LPS-stimulated PBMCs. The biological activity of Satanin 1, 2 and Curvicin makes them interesting leads for antimicrobial strategies.

Two mitochondrial genomes of Taiwanese rhinoceros beetles, Oryctes rhinoceros and Eophileurus chinensis (Coleoptera: Scarabaeidae).

Two mitochondrial genomes of the dynastine beetles, Oryctes rhinoceros (Linnaeus, 1758) and Eophileurus chinensis (Faldermann, 1835), were assembled via high-throughput sequencing (HTS). Each of the mitogenomes has 37 genes, showing standard gene order and annotation as the other insects, except for the transfer genes, presenting tQ-tI-tM order. To examine their phylogenetic positions, 118 public mitogenomes of Scarabaeidae were used to infer a ML tree. Overall, our scarabaeid phylogeny reveals clear relationships with high nodal supports, and the two rhinoceros beetles are both grouped with the subfamily Dynastinae. The feeding habit of the two clades seems to represent coprophagous and phytophagous types. However, polyphyletic relationships were observed in the subfamily Melolothinae and in the tribes of Onthophagini and Oniticellini. Further systematic revision is needed.

Can Sexual Selection Drive the Evolution of Sperm Cell Structure?

Sperm cells have undergone an extraordinarily divergent evolution among metazoan animals. Parker recognized that because female animals frequently mate with more than one male, sexual selection would continue after mating and impose strong selection on sperm cells to maximize fertilization success. Comparative analyses among species have revealed a general relationship between the strength of selection from sperm competition and the length of sperm cells and their constituent parts. However, comparative analyses cannot address causation. Here, we use experimental evolution to ask whether sexual selection can drive the divergence of sperm cell phenotype, using the dung beetle Onthophagus taurus as a model. We either relaxed sexual selection by enforcing monogamy or allowed sexual selection to continue for 20 generations before sampling males and measuring the total length of sperm cells and their constituent parts, the acrosome, nucleus, and flagella. We found differences in the length of the sperm cell nucleus but no differences in the length of the acrosome, flagella, or total sperm length. Our data suggest that different sperm cell components may respond independently to sexual selection and contribute to the divergent evolution of these extraordinary cells.

[Effects of dung beetles on decomposition of cattle dung in spring and autumn in a Seriphi-dium-dominated desert, China.] / ç²ªç”²è™«å¯¹ç»¢è’¿è’æ¼ æ˜¥ç§‹ä¸¤å­£ç‰›ç²ªåˆ†è§£çš„å½±å“.

To understand the decomposition of cattle dung in Seriphidium-dominated desert, the changes of dung physical and chemical properties were determined by setting different stacking times (0, 7, 29, 48, 58 h) in May (spring) and September (autumn), respectively. Mesh cage with different openings (no mesh cage, opening up and down, opening up, totally enclosed) were set up to explore the effects of different ecological functional groups of dung beetles on decomposition. The results showed that species richness of dung beetles in spring was significantly higher than that in autumn, and that the abundance of dung beetles in autumn was significantly higher than that in spring. The losses of moisture, total carbon, total nitrogen and total phosphorus in dung were mainly concentrated during 0-29 h in spring, being decreased by 39.4%, 13.9%, 32.1% and 26.7% at 29 h, respectively. Neutral detergent fiber and acid detergent fiber of the dung stacked for 58 h decreased significantly by 8.0% and 16.0% respectively. In autumn, moisture, neutral detergent fiber and acid detergent fiber decreased most rapidly during 0-7 h, being decreased by 85.6%, 10.2% and 20.2% at 7 h, respectively. The concentrations of neutral detergent fiber and acid detergent fiber increased during 7-58 h by 20.0% and 13.7%, respectively. The decomposition of total carbon, total nitrogen and total phosphorus mainly concentrated during 0-29 h, being reduced by17.5%, 55.0% and 64.8%, respectively. The mesh cage with different openings effectively prevented the entering of dung beetles from the corresponding ecological functional groups. With the increases of functional groups of dung beetles, the decomposition rate accelerated, with cattle dung of no mesh cage being significantly higher than other treatments. The species richness and abundance of dung beetles and the stacking time of dung significantly affected the decomposition of cattle dung.

First report of Spirocerca lupi larva in dung beetles (Scarabaeus armeniacus) in the central region of Iran: A morphological and molecular identification.

Dung beetles as detritivores insects, naturally use feces of vertebrates as foods and reproduction beds. This leads to frequent contacts between dung beetles and parasitic helminths. The current study was carried out to assess infections of dung beetles with larval stages of helminths in rural areas of Taleqan County, Alborz Province, Iran. A total number of 200 dung beetles were collected randomly in June 2017 from the highlands of Taleqan County. Beetles were dissected in normal saline and carefully studied using a stereomicroscope. Morphological characteristics of the recovered larvae were drawn using a camera lucida equipped microscope at 400× magnification. Then, genomic DNAs of the recovered larvae extracted and PCR amplifications of the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene were carried out and the amplicons were sequenced. All collected dung beetles identified as Scarabaeus armeniacus from the Scarabaeidae family (55.5 % were male and 44.5 % female). Three females of the beetles have been found to be naturally infected with the third stage larvae of Spirocerca lupi. The average length and width of the larvae were 2.95 (2.81-3.15; CI 95 %) and 0.12 (0.1-0.15; CI 95 %) mm, respectively. The phylogenetic analysis showed that S. lupi belonged to a clade within the Spirocercidae family. In the current study, S. armeniacus introduced as a potential biological vector for transmission of S. lupi to vertebrates in the region. To the best of the authors' knowledge, this is the first report on the larval stages of S. lupi in S. armeniacus.