Scarabaeidae Research Articles

Dual identity: the ecology and behaviour of the robber fly Mallophora ruficauda, a pest of honeybees and parasitoid of Scarab beetles

Dual identity: the ecology and behaviour of the robber fly Mallophora ruficauda, a pest of honeybees and parasitoid of Scarab beetles

Morphological differences on the mouthparts among six species of cockchafer (Coleoptera: Melolonthinae), with discussions on their feeding habits

Melolonthinae represent a megadiverse assemblage of scarab beetles, exhibiting dramatic diversity of feeding habits on the tribal or generic level. As the core feeding apparatus, mouthparts have been relatively underexplored morphologically among genera or tribes within Melolonthinae. In this study, we conducted a detailed dissection and scanning electron microscopic (SEM) analysis of the adult mouthparts from six species across four tribes within Melolonthinae, to provide new morphological characters. The mouthparts exhibit considerable morphological diversity, including variations in labral notches, invaginations on epipharynx, mandibular structures, and the arrangement of setae on the labia. Using SEM, we observed paired invaginations on the epipharynx in Brahmina faldermanni, Hilyotrogus bicoloreus, Polyphylla laticollis and Melolontha incana, which are absent in the Miridiba trichophora, and Apogonia niponica. The structural diversity may be linked to the different feeding habits of these beetles, a relationship that is briefly discussed in the study.

Antennal sensilla of Cyclocephala barrerai (Coleoptera: Melolonthidae): morphology, sexual dimorphism, allometric relationships, and function.

Scarab beetles use pheromones and volatiles to search for their partners and host plants. The perception of these compounds occurs in the beetle antennae, particularly in the sensilla. Relatively few studies have morphologically and physiologically characterized the sensilla of scarab beetles. Cyclocephala barrerai Martínez is a beetle distributed in Mexico. Male beetles have larger antennal lamellae than females, and in both cases, the size of this structure is related to their weight. Previous studies have reported that both sexes are attracted to bacterial volatiles isolated from the female genital chambers. Female cuticular hydrocarbons may act as a sexual contact pheromone. However, antennal sensilla and their electrophysiological responses to behaviorally relevant compounds remain to be investigated. Here, we describe and report the types, allometric relationships, and functions of sensilla found in the lamellae of both C. barrerai sexes. Sensilla were identified, classified, measured, and counted to identify intra and intersexual relationships. The single sensillum recordings showed that plant volatiles, hydrocarbons, and heat stimulated receptor neurons. We identified 2 new types of sensilla basiconica in the scape. Males have more and larger antennal sensilla placodea IV, which specializes in detecting pheromones, plant volatiles, and heat. Females have a greater diversity of sensilla.

New observations on prey scarab beetles and host plants of the green lynx spider, Peucetia viridans (Hentz, 1832) (Araneae: Oxyopidae) in Oaxaca, Mexico

ABSTRACT Peucetia viridans (Hentz), commonly called the lynx spider, is an important predator with a diet that encompasses a wide variety of insects and arachnids, including cannibalism. Although several studies that address aspects related to its ecology and behaviour have been carried out, there is a notable lack of studies focused on the recording of its prey and hosts. This information gap is particularly evident regarding the interaction of the spider with beetles belonging to the family Scarabaeidae. To contribute to the knowledge of the feeding habits and host preferences of P. viridans, observations were made in two localities of the Valles Centrales region of Oaxaca, Mexico. Lynx spiders were observed on Croton ciliatoglandulifer Ortega, Lantana camara Linnaeus, Solanum mitlense Dunal, and Wigandia urens (Ruiz and Pav.) Kunth. Spiders utilise these plants as shelter and to ambush their prey, thereby reducing herbivore populations and protecting the plants. In return, the plants provide the spiders with prey and floral and extrafloral nectaries as food sources. Therefore, spiders and plants have a facultative mutualistic relationship, whereas the relationship between spiders and herbivores is antagonistic. For the first time Diplotaxis trapezifera Bates, Macrodactylus fulvescens Bates, Paranomala discoidalis (Bates), Strigoderma costulipennis Bates, Strigoderma sulcipennis Burmeister, and Euphoria pulchella (Gory and Percheron) as prey, and Wigandia urens, Lantana camara and Solanum mitlense as host plants are recorded. A checklist of host plants for P. viridans is given. Overall, these new observations highlight the importance that tritrophic interactions (plant–herbivore–natural enemy) have in wild systems, which are essential for maintaining ecological balance.

Identification and field verification of the aggregation pheromone components produced by male Holotrichia parallela Motschulsky (Coleoptera: Scarabaeidae).

The chafer beetle, Holotrichia parallela, causes damage to numerous economically significant crops worldwide. Adult beetles exhibit aggregation behavior likely mediated by a male-produced pheromone. Advancements in biological research technology have facilitated the identification of insect aggregation pheromones and promoted their applications as bait for trapping and monitoring pests. Currently, only a few active components of aggregation pheromones from Holotrichia species have been identified. However, the specific components of aggregation pheromones produced by H. parallela remain unknown. In this study, we initially observed from Y-tube olfactometer assays that both male and female H. parallela were significantly attracted to volatiles emitted by males, but not to those from females. We then collected hindgut crude extracts of male adults and carried out gas chromatography-mass spectrometry analysis to identify potential aggregation pheromone components. Pentadecyl acetate, cis-13-docosenol, and behenic acid were identified as male-specific compounds in comparison to female extracts, serving as components of the aggregation pheromone in H. parallela. We further evaluated their attractiveness to H. parallea in both laboratory and field experiments. In laboratory settings, pentadecyl acetate, cis-13-docosenol, and behenic acid evoked significant responses to both males and females at specific concentrations, as evidenced by both electroantennography tests and behavioral bioassays. Under field conditions, traps baited with these three compounds captured significantly more H. parallela adults compared to control traps. In this study, we found that pentadecyl acetate, cis-13-docosenol, and behenic acid are specifically present in male H. parallela, serving as aggregation pheromones. Both laboratory and field-trapping experiments suggest their potential as monitoring and controlling tools against H. parallela adults. © 2024 Society of Chemical Industry.

Museomics reveal origins of East African Pleophylla forest chafers and Miocene forest connectivity

Here we present a nearly complete species-level phylogeny including 23 of the 25 known species of the forest-dwelling herbivorous scarab chafer beetle genus Pleophylla (Coleoptera: Scarabaeidae: Sericinae), based on the analysis of 950 nuclear genes (metazoan-level universal single-copy orthologs; mzl-USCOs). DNA sequences were obtained from freshly collected, ethanol-preserved samples and from dried museum specimens by target enrichment or genome shotgun sequencing. Alignment completeness of mzl-USCOs newly obtained here by target DNA enrichment of ethanol samples were very heterogenous and lower (29–62 %) than in Dietz et al. (2023a), while that of sequences recovered from dried samples was even lower (∼19 %). Alignment completeness of the sequences obtained from low coverage shotgun sequencing was highest (∼92 %), although the average coverage was much lower than for the target enrichment samples. We used the resulting phylogeny to reconstruct the historical biogeography of the group. To estimate a time-calibrated tree, we combined the mzl-USCO data of Pleophylla with a nucleotide alignment from an available transcriptomic dataset of Scarabaeoidea and used two different sets of secondary calibration points. Despite the problems associated with the capture rate of mzl-USCO sequences from museum specimens, we were able to infer a well-resolved phylogeny of the genus Pleophylla that also provided reliable estimates of the phylogenetic position of species for which we had little sequence data. Our study clearly identified South Africa as the geographic origin of Pleophylla. Timing and biogeographic history confirm a persistent fragmentation of forests since the Eocene. The occurrence of only one long-distance dispersal event from southern Africa to the Eastern African Arc even during the Miocene highlights the limited dispersal possibilities for these forest-adapted chafers, which do not seem to have had important northerly range expansions along hypothetical forest corridors during the Pleistocene.

How to control nasty scarabs? Effectiveness of the generalist entomopathogenic fungus Metarhizium brunneum against garden chafer larvae

Several scarab beetles (Scarabaeidae) cause major damage in agriculture, horticulture, and forestry. Especially root feeding scarab larvae cause substantial economic losses on crops, forage plants and recreational areas. In Europe, the entomopathogenic fungi (EPF) Beauveria brongniartii and Metarhizium brunneum are applied against the most problematic, native scarabs, the common cockchafer (Melolontha melolontha) and the garden chafer (Phyllopertha horticola). While the control of cockchafer larvae with B. brongniartii is well-researched, conclusive results from field applications for the control of the garden chafer with M. brunneum remain elusive. We therefore assessed the performance of commercially available fungal strains of M. brunneum against garden chafer larvae in pot and large-scale field experiments.The application of M. brunneum significantly increased the abundance of fungal propagules in the soil by approximately a factor of ten, irrespective of high levels of naturally occurring Metarhizium spp. Furthermore, the applied strains infected and propagated on the larvae and the mortality of garden chafer larvae was slightly increased due to the fungal treatments. We found three other EPF species frequently infecting garden chafer larvae (mean infection rates: 13–25%), including B. brongniartii which is considered to be a specific pathogen of the cockchafer. Thus, the applied fungal strains were only part of a consortium of natural enemies which reduces garden chafer populations strongly as a whole. Hence, we suggest that the application of EPF may be advisable on areas with reduced natural enemies such as golf courses but is probably redundant on meadows harboring a diverse consortium of antagonists.

Variation and functional profile of gut bacteria in the scarab beetle, Anomala dimidiata, under a cellulose-enriched microenvironment

This study utilized cultivable methods and 16 S amplicon sequencing to compare taxonomic profiles and functional potential of gut bacteria in the scarab beetle, Anomola dimidiata, under cellulose-enriched conditions. Eight culturable cellulolytic gut bacteria were isolated from the midgut and hindgut of the scarab larvae, respectively. 16 S amplicon sequencing evinced that the most represented taxonomic profiles at phylum level in the fermentation chamber and midgut were Bacillota (71.62 and 56.76%), Pseudomonadota (22.66 and 36.89%) and Bacteroidota (2.7 and 2.81%). Bacillota (56.74 and 91.39%) were significantly enriched in the midgut with the addition of cellulose. In contrast, Bacillota and Psedomonadota were significantly enriched in the fermentation chamber. Carbohydrate metabolism was up-regulated in the midgut, while nitrogen and phosphorus metabolism were up-regulated in the fermentation chamber, suggesting these symbionts’ possible metabolic roles to the host. An analysis of total cellulases as well as amplicon sequence variants indicated that the gut bacteria belonging to Acinetobacter, Bacillus, Brucella, Brevibacillus, Enterobacter, Lysinibacillus and Paenibacillus are involved in nutrition provisioning. These results have provided additional insights into the gut bacteria associated with cellulose digestion in A. dimidiata and created a platform for bioprospecting novel isolates to produce biomolecules for biotechnological use, besides identifying eco-friendly targets for its management.

The first report of complete mitogenomes of two endangered species of genus Propomacrus (Coleoptera: Scarabaeidae: Euchirinae) and phylogenetic implications.

To understand the mitochondrial genome structure of two endangered and long-armed scarab beetles, Propomacrus davidi and Propomacrus bimucronatus, their complete mitogenomes were sequenced for the first time in this study. The complete mitogenomes of P. davidi and P. bimucronatus were 18, 042 bp and 18, 104 bp in length, respectively. The gene orders of their mitogenomes were highly consistent with other Coleopteran species, and the typical ATN was used as the start codon in most protein coding genes. The incomplete stop codon T was used in cox1, cox2, and nad5, and TAN was used as a complete stop codon in most protein coding genes. All predicted tRNAs could form a typical cloverleaf secondary structure, except that trnS1 lacked the dihydrouridine arm. Based on the maximum likelihood and the Bayesian inference methods, phylogenetic trees of 50 species were reconstructed. The results showed that P. davidi, P. bimucronatus, Cheirotonus jansoni and Cheirotonus gestroi clustered in the same branch, and were the most closely related. The results supported that subfamily Euchirinae is a monophyletic group of Scarabaeidae, which was consistent with the morphological classification. These molecular data enriched the complete mitogenome database of Euchirinae, and improved our understanding of the phylogenetic relationship and evolutionary characteristics of these two endangered species.

Transcriptomic and Gene Expression Analysis of Chemosensory Genes from White Grubs of Hylamorpha elegans (Coleoptera: Scarabaeidae), a Subterranean Pest in South America.

Olfaction and gustation processes play key roles in the life cycle of insects, such as finding and accepting food sources, oviposition sites, and mates, among other fundamental aspects of insect development. In this context, chemosensory genes found in sensory organs (e.g., antennae and maxillary palps) are crucial for understanding insect behaviour, particularly the phytophagous behaviour of insect pests that attack economically important crops. An example is the scarab beetle Hylamorpha elegans, which feeds on the roots of several crops important for livestock in its larval stage. In this study, chemosensory gene candidates of H. elegans white grubs identified through the head transcriptome and phylogenetic and tissue-biased gene expression (antennae, head without antennae, and legs) have been reported. Overall, 47 chemosensory genes were identified (2 ORs, 1 GR, 11 IRs, 9 CSPs, and 24 OBPs). Gene expression analysis revealed the predominant presence of IRs in the legs, whereas ORs and the GR were present in the heads and/or antennae. Particularly, HeleOBP9 and HeleCSP2 were significantly expressed in the head but not in the antennae or legs; these and other genes are discussed as potential targets in the context of H. elegans management.

Seven new species of Spatulaphorus Rack (Acari: Pygmephoridae) phoretic on scarab beetles (Coleoptera: Scarabaeidae)

Seven new species of Spatulaphorus (Acari: Pygmephoridae) are described from female mites phoretic on scarab beetles (Coleoptera: Scarabaeidae), as follows: Spatulaphorus incisus sp. nov. and S. spinisetus sp. nov. from Brazil on Sulcophanaeus faunus and Dichotomius buqueti, respectively; S. brevisetosus sp. nov. from the USA on Phanaeus igneus; S. longisetosus sp. nov. from the USA on Phanaeus difformis and Ph. vindex; S. madagascariensis sp. nov. from Madagascar on Helictopleurus corruscus; S. reductus sp. nov. from Argentina on Ataenius picinus, A. platensis, and A. clavatus, and Parataenius simulator, and S. venezuelaensis sp. nov. from Venezuela from Phanaeus prasinus. Spatulaphorus imbricatipes (Mahunka, 1980) comb. nov. is moved from Pygmephorellus. A key to the world species of the genus Spatulaphorus is also provided.

Species composition of phytophages on ornamental plants

Goal. Monitoring the phytosanitary status and determining the species composition of phytophages on decorative coniferous and deciduous plants. Methods. Field — determination of the species composition of pests and the dynamics of the number of main species; laboratory — determination of pests selected on experimental plots. Research was conducted in accordance with generally accepted methods in entomology and plant protection. Results. In the industrial plant nursery of open soil «Megaplant» located in the Kyiv region, Fastiv district, village The monitoring of the phytosanitary state of ornamental plant plantations was carried out in Trilys. The natural saturation of harmful organisms and the level of their harmfulness were studied. Conclusions. It has been established that plants in industrial nurseries in open ground are damaged by a large number of insects and mites. The most dangerous and widespread on conifer ornamental plants were 8 pests from the following families coccids (Coccidae), bark beetles (Scolytidae), adelgids (Adelgidae), snout beetles (Curculionidae) and spider mites (Tetranychidae); 9 most harmful species from the following families were noted on decorative leafy plants: crambid Snout Moths (Crambidae), mealybugs (Pseudococcidae) and аrmored scales or diaspidids (Diaspididae), eriophyidae mites (Eriophyidae), aphids (Aphididae), snout beetles (Curculionidae), scarab beetles (Scarabaeidae).

Comparison of different attract-and-kill device densities to control the adult population of Popillia japonica (Coleoptera: Scarabaeidae).

Popillia japonica Newman is a scarab beetle native to Japan that is considered a serious pest outside its native range. It can feed on more than 400 host plants and spread about 10 km per year in invaded territories, therefore it is considered the second most important quarantine pest in Europe. Both chemical and biological insecticides have been used for control, with variable results. Despite ongoing efforts, P. japonica remains a threat in invaded countries, and it is necessary to test more effective and sustainable solutions in the context of integrated pest management. Here we present a study on long-lasting insecticide-treated nets (LLINs) assembled in semiochemical-baited attract-and-kill devices (A&Ks) as a means to control adults of P. japonica with low environmental impact. This study complements previous ones in which we first evaluated the effectiveness of the LLINs in the laboratory and then tested both effectiveness and duration in field-exposed A&Ks against P. japonica. In the present work we compared the effectiveness of three different densities of A&Ks per hectare in areas where the population of P. japonica was numerically homogeneous. The different densities of A&K (1, 2, 4 A&Ks per ha) resulted in an overall reduction of the population of P. japonica by about two thirds in comparison to the control area. This study suggests that the use of one A&K per hectare, requiring minimal management effort, is an effective ratio for reducing local populations of P. japonica. © 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

New data on distribution of the pleurosticti endemic scarab beetles (Coleoptera: Scarabaeidae: Melolonthinae) and a new pest from Goa, India

Abstract The white grubs are cosmopolitan in distribution and a major pest of several economically important crops. A study was conducted to assess the diversity of these phytophagous beetles in and around South Goa in 2023. The adult beetles were collected by installing light traps in the field. The study resulted in new pest records from Goa. The two new records are Holotrichia fissa Brenske, 1894 and Sophrops karschi (Brenske, 1892). Keywords: Holotrichia, Sophrops, light trap, white grubs, new record.

Dung-beetles (Coleoptera, Scarabaeidae, Aphodiinae, Scarabaeinae) feeding on faeces of steppe marmots Marmotabobak (Rodentia, Sciuridae) in Middle Volga territory.

In open terrestrial biomes of Holarctic realm, ground squirrels are recognised as keystone species inhabiting steppes. They shape the plant species composition and diversity and support a fauna of species associated with their burrows. Ground squirrels and associated dung-beetles are important elements of the steppe food webs, yet the trophic associations between species are still poorly studied. The area in the northern outskirts of Obshchy Syrt plateau, on the border of Samara and Orenburg Provinces of Russia was surveyed and scarab beetles (Scarabaeidae) feeding on steppe marmot (Marmotabobak (Müller, 1776)) faeces were collected from six localities. Twenty eight species of two subfamilies - Aphodiinae and Scarabaeinae, - were identified with the majority of species belonging the genus Aphodius Hellwig, 1798. Seven species are recorded as consumers of marmot faeces for the first time. Only two nidicolous specialist species were found which suggests that the studied population of steppe marmots is as result of the recent secondary colonisation and not all the associated scarab beetle faunas were re-established.

Gymnetis litigiosa Gory & Percheron, 1833 (Coleoptera: Scarabaeidae: Cetoniinae: Gymnetini): first occurrence of this exotic species in Chile

The subfamily Cetoniinae, the genus Gymnetis MacLeay, and the species Gymnetis litigiosa Gory & Percheron are recorded for the first time in Chile, based on specimens collected in the cities of San Felipe de Aconcagua, Los Andes (Valparaíso Region) and Santiago (Metropolitan Region). This new record increases to four the number of exotic scarab beetles introduced and established in the country and extends the known distribution area of the species to the western slope of the Andes mountain range. A brief diagnosis for recognition of the species, adult photographs, distribution, and natural history data are provided. The possible route of entry of this cetoniid into Chile is discussed.

Updating checklist of family scarabaeidae (Coleoptera) in Egypt

Updating checklist of family scarabaeidae (Coleoptera) in Egypt

Multifactorial structuring in a local guild of coprophilic scarab beetles from theMexicantransition zone: Analyses of ecological hypotheses

AbstractDifferent hypotheses have been proposed to explain the environmental gradients‐biotic structuring relationship. Nevertheless, several inconsistencies have arisen when only one hypothesis is chosen to explain the biological diversity patterns. Our aim is to test a multiple hypotheses approach to explain the structure of a coprophilic scarab local guild.Coprophilic Scarabaeoidea beetles were sampled for 33 sites along the study region (Los Chimalapas, Oaxaca, Mexico). Several environmental variables were used to test four hypotheses for geographic gradients: Productivity, ambient energy, habitat heterogeneity and temporal heterogeneity. Generalised linear mixed models were used to test the relationship of the hypotheses on the abundance, species richness and Shannon‐Wiener diversity of the local guild. Moreover, canonical correspondence analysis was performed to analyse the effects on species composition.Abundance was negatively affected by the simultaneous effect between two habitat heterogeneity factors, while both species richness (positive effect) and Shannon‐Wiener diversity (negative effect) were mainly related to productivity, and species composition was mainly explained by habitat heterogeneity.We conclude that multiple hypotheses, both based on species‐energy and heterogeneity, need to be considered to explain biotic setting of communities, ensembles, assemblages, local guilds and other complex biotic systems.

A Study on Scarabaeoidea (Insecta:Coleoptera) Fauna of Yavşan Plateau Nature Park (Kahramanmaraş-Türkiye)

It is of great significance to reveal the insect fauna of Kahramanmaraş, which has different ecosystems and climatic conditions, in terms of biological diversity. This study investigated the Scarabaeoidea fauna of Yavşan Plateau which is located in Kahramanmaraş and which was declared as a nature park in 2009. The present study examined adult Scarabaeoidea specimens collected between March and October 2016. The specimens were obtained throughpitfall the trap method and field search method (using tools such as forceps, etc.).The findings demonstrated that 28 species and 5 subspecies belonging to 25 genera from the Scarabaeoidea superfamily were identified in the study area. 31 of them belong to the family Scarabaeidae, while two species are included in the family Hybosoridae amongst them. Elaphocera dilatata (Erichson, 1840) was recorded for the first time from Türkiye. 14 of the recorded species and subspecies were reported for the first time for fauna of Kahramanmaraş province. The study covers the distribution of the identified species in Türkiye and throughout the world as well as their chorotype information, locality and history. This study is expected to shed light onto the ever-decreasing biodiversity due to various reasons such as global climate change, habitat degradation etc.

Can we manage alien invasive insects without altering native soil faunal communities? A field trial on Popillia japonica

Biological and integrated pest control are key assets to environmentally friendly management of cropland. Use of entomopathogens against target pests is common, yet the effects of such released organisms on native, non-target invertebrates are currently poorly known. This is particularly true for relatively inconspicuous components of agroecosystems such as soil biological biota. Popillia japonica, a polyphagous alien invasive scarab beetle native to Japan, is now present in Europe where huge efforts are being conducted to control the pest and slow its spread. In particular, entomopathogenic nematodes and fungi have been used for larval control. Here we test the effects of those agents on both P. japonica larvae and non-target soil biota by comparing soil arthropod assemblages before and after treatment of field plots in an irrigated perennial meadow.Application of an indigenous strain of the nematode Heterorhabditis bacteriophora resulted in significant reduction in numbers of P. japonica larvae. In contrast, an indigenous strain of the entomopathogenic fungus Metarhizium robertsii failed to provide significant control. We found no evident effect on non-target edaphic arthropods under either treatment in comparison to untreated control plots. Some taxa, namely Collembola and Acarina, showed a disproportionate increase in treated plots, suggesting that some changes may occur in the long term, at least in particular arthropod groups. Our results suggest the selected strain of H. bacteriophora is an excellent candidate for managing P. japonica larvae with minimal adverse impact on non-target species and ecosystem functioning.