Beetle Larvae Research Articles

First Data on the Investigation of Gut Yeasts in Hermit Beetle (Osmoderma barnabita Motschulsky, 1845) Larvae in Lithuania.

In this study, yeasts from the gut of O. barnabita larvae were isolated and molecularly identified. It is worth noting that this research provides the first analysis of the gut yeast community in O. barnabita larvae in Lithuania, which is a significant contribution to the field. Two hermit-like L3-praepupa instars were collected from a decaying oak log in Lithuania. The isolation, morphology, biochemistry, and physiology of the yeast isolates were characterized using standards commonly employed in yeast taxonomy studies. The isolates were identified by sequencing the large subunit (26S) rDNA (D1/D2 domain of the LSU). All gut compartments were colonized by the yeast. A total of 45 yeast strains were obtained from the gut of both O. barnabita larvae, with 23 strains originating from Larva 1, 16 strains from Larva 2, and 6 strains from the galleries. According to our identification results of the 45 yeast strains, most of the species were related to Ascomycota, with most of them belonging to the Saccharomycetales order. Yeasts of the genera Candida, Debaryomyces, Meyerozyma, Priceomyces, Schwanniomyces, Spencermartinsiella, Trichomonascus, and Blastobotrys were present in gut of O. barnabita larvae. Species of the Trichosporonales order represented the Basidiomycota phylum.

Plant metabolic responses to soil herbicide residues differ under herbivory in two woodland strawberry genotypes

The use of glyphosate-based herbicides (GBHs) to control weeds has increased exponentially in recent decades, and their residues and degradation products have been found in soils across the globe. GBH residues in soil have been shown to affect plant physiology and specialised metabolite biosynthesis, which, in turn, may impact plant resistance to biotic stressors.In a greenhouse study, we investigated the interactive effects between soil GBH residues and herbivory on the performance, phytohormone concentrations, phenolic compound concentrations and volatile organic compound (VOC) emissions of two woodland strawberry (Fragaria vesca) genotypes, which were classified as herbivore resistant and herbivore susceptible. Plants were subjected to herbivory by strawberry leaf beetle (Galerucella tenella) larvae, and to GBH residues by growing in soil collected from a field site with GBH treatments twice a year over the past eight years.Soil GBH residues reduced the belowground biomass of the susceptible genotype and the aboveground biomass of both woodland strawberry genotypes. Herbivory increased the belowground biomass of the resistant genotype and the root–shoot ratio of both genotypes. At the metabolite level, herbivory induced the emission of several VOCs. Jasmonic acid, abscisic acid and auxin concentrations were induced by herbivory, in contrast to salicylic acid, which was only induced by herbivory in combination with soil GBH residues in the resistant genotype. The concentrations of phenolic compounds were higher in the resistant genotype compared to the susceptible genotype and were induced by soil GBH residues in the resistant genotype.Our results indicate that soil GBH residues can differentially affect plant performance, phytohormone concentrations and phenolic compound concentrations under herbivore attack, in a genotype-dependent manner. Soil GBH altered plant responses to herbivory, which may impact plant resistance traits and species interactions. With ongoing agrochemical pollution, we need to consider plant cultivars with better resistance to polluted soils while maintaining plant resilience under challenging environmental conditions.

How to Overcome a Snail? Identification of Putative Neurotoxins of Snail-Feeding Firefly Larvae (Coleoptera: Lampyridae, Lampyris noctiluca).

The larvae of some lampyrid beetles are highly specialized predators of snails. They have been observed to climb on the shells of their prey and use this exposed position to bite and inject secretions potentially originating from the midgut. Besides serving the purpose of extra-oral digestion (EOD), injected compounds also seem to have a paralyzing effect. Up to now, the toxins causing this paralyzing activity have not been identified. In the current study, we provide a first compositional analysis of the midgut secretion from lampyrid larvae, with a focus on identifying putative neurotoxins causing the observed paralyzing effect. For this purpose, we utilized a combined proteo-transcriptomic approach to characterize the compounds present in the midgut secretion of larval stages of Lampyris noctiluca. In terms of the absolute numbers of identified compounds, the midgut secretion is dominated by hydrolyzing enzymes comprising peptidases, carboxylesterases, and glycosidases. However, when considering expression levels, a few rather short cysteine-rich peptides exceed all other compounds. Some of these compounds show moderate similarity to putative neurotoxins identified in the venom of other arthropods and could be responsible for paralyzing effects. In addition to these potential toxins, we provide a list of peptides typical of the midgut secretion of L. noctiluca, supplemented by the corresponding precursor sequences.

Environment-Mediated Vertical Transmission Fostered Uncoupled Phylogenetic Relationships between Longicorn Beetles and Their Symbionts.

The Coleoptera Cerambycidae (longicorn beetles) use wood under different states (living healthy, freshly snapped, completely rot, etc.) in a species-specific manner for their larval diet. Larvae of some Cerambycidae groups have mycetomes, accessory organs associated with the midgut that harbor fungal symbiont cells. The symbionts are thought to improve nutrient conditions; however, this has yet to be shown experimentally. To deduce the evolutionary history of this symbiosis, we investigated the characteristics of the mycetomes in the larvae of longicorn beetles collected in Japan. Lepturinae, Necydalinae, and Spondylidinae are the only groups that possess mycetomes, and these three groups' mycetomes and corresponding fungal cells exhibit different characteristics between the groups. However, the phylogenetic relationship of symbiont yeasts does not coincide with that of the corresponding longicorn beetle species, suggesting they have not co-speciated. The imperfect vertical transmission of symbiont yeasts from female to offspring is a mechanism that could accommodate the host-symbiont phylogenetic incongruence. Some Lepturinae species secondarily lost mycetomes. The loss is associated with their diet choice, suggesting that different conditions between feeding habits could have allowed species to discard this organ. We found that symbiont fungi encapsulated in the mycetomes are dispensable for larval growth if sufficient nutrients are given, suggesting that the role of symbiotic fungi could be compensated by the food larvae take. Aegosoma sinicum is a longicorn beetle classified to the subfamily Prioninae, which does not possess mycetomes. However, this species contains a restricted selection of yeast species in the larval gut, suggesting that the symbiosis between longicorn beetles and yeasts emerged before acquiring the mycetomes.

Nutritional composition of edible wood borer beetle larvae in Kenya

Nutritional composition of edible wood borer beetle larvae in Kenya

Mitogenome architecture supports the non-monophyly of the cosmopolitan parasitoid wasp subfamily Doryctinae (Hymenoptera: Braconidae) recovered by nuclear and mitochondrial phylogenomics.

Mitochondrial DNA gene organisation is an important source of phylogenetic information for various metazoan taxa at different evolutionary timescales, though this has not been broadly tested for all insect groups nor within a phylogenetic context. The cosmopolitan subfamily Doryctinae is a highly diverse group of braconid wasps mainly represented by ectoparasitoids of xylophagous beetle larvae. Previous molecular studies based on Sanger and genome-wide (ultraconserved elements, UCE; and mitochondrial genomes) sequence data have recovered a non-monophyletic Doryctinae, though the relationships involved have always been weakly supported. We characterised doryctine mitogenomes and conducted separate phylogenetic analyses based on mitogenome and UCE sequence data of ~100 representative doryctine genera to assess the monophyly and higher-level classification of the subfamily. We identified rearrangements of mitochondrial transfer RNAs (tRNAs) that support a non-monophyletic Doryctinae consisting of two separate non-related clades with strong geographic structure ('New World' and 'Old World' clades). This geographic structure was also consistently supported by the phylogenetic analyses preformed with mitogenome and UCE sequence data. These results highlight the utility of the mitogenome gene rearrangements as a potential source of phylogenetic information at different evolutionary timescales.

Protein complexes from edible mushrooms as a sustainable potato protection against coleopteran pests.

Protein complexes from edible oyster mushrooms (Pleurotus sp.) composed of pleurotolysin A2 (PlyA2) and pleurotolysin B (PlyB) exert toxicity in feeding tests against Colorado potato beetle (CPB) larvae, acting through the interaction with insect-specific membrane sphingolipid. Here we present a new strategy for crop protection, based on in planta production of PlyA2/PlyB protein complexes, and we exemplify this strategy in construction of transgenic potato plants of cv Désirée. The transgenics in which PlyA2 was directed to the vacuole and PlyB to the endoplasmic reticulum are effectively protected from infestation by CPB larvae without impacting plant performance. These transgenic plants showed a pronounced effect on larval feeding rate, the larvae feeding on transgenic plants being on average five to six folds lighter than larvae feeding on controls. Further, only a fraction (11%-37%) of the larvae that fed on transgenic potato plants completed their life cycle and developed into adult beetles. Moreover, gene expression analysis of CPB larvae exposed to PlyA2/PlyB complexes revealed the response indicative of a general stress status of larvae and no evidence of possibility of developing resistance due to the functional inactivation of PlyA2/PlyB sphingolipid receptors.

Sublethal effects of a commercial Bt product and Bt cotton flowers on the bollworm (Helicoverpa zea) with impacts to predation from a lady beetle (Hippodamia convergens).

Insecticidal Bacillus thuringiensis Berliner (Bt) toxins produced by transgenic cotton (Gossypium hirsutum L.) plants have become an essential component of cotton pest management. Bt toxins are the primary management tool in transgenic cotton for lepidopteran pests, the most important of which is the bollworm (Helicoverpa zea Boddie) (Lepidoptera: Noctuidae) in the United States (U.S.). However, bollworm larvae that survive after consuming Bt toxins may experience sublethal effects, which could alter interactions with other organisms, such as natural enemies. Experiments were conducted to evaluate how sublethal effects of a commercial Bt product (Dipel) incorporated into artificial diet and from Bt cotton flowers impact predation from the convergent lady beetle (Hippodamia convergens Guérin-Méneville) (Coleoptera: Coccinellidae), common in cotton fields of the mid-southern U.S. Sublethal effects were detected through reduced weight and slower development in bollworm larvae which fed on Dipel incorporated into artificial diet, Bollgard II, and Bollgard 3 cotton flowers. Sublethal effects from proteins incorporated into artificial diet were found to significantly alter predation from third instar lady beetle larvae. Predation of bollworm larvae also increased significantly after feeding for three days on a diet incorporated with Bt proteins. These results suggest that the changes in larval weight and development induced by Bt can be used to help predict consumption of bollworm larvae by the convergent lady beetle. These findings are essential to understanding the potential level of biological control in Bt cotton where lepidopteran larvae experience sublethal effects.

Elateriform beetle larvae preserved in about 100-million-year-old Kachin amber

Beetle larvae show high diversity in forms and ecological roles. Beetle larvae are often roughly categorised into certain larval types, for example: campodeiform, onisciform, scarabeiform, or elateriform. Larvae of the latter type are virtually absent from the fossil record. Here, we report three amber pieces from Cretaceous Kachin amber, Myanmar (about 100 million years old) that together include nine elateriform beetle larvae. One of the amber pieces has a single specimen included. The specimen is interpreted as a larva of Elateridae, the group of click beetles, possibly of the ingroup Elaterinae; yet accessible details are limited. Eight specimens within the other two amber pieces show certain similarities with larvae of Elateridae, but show significant differences in the trunk end, which bears two lobes armed with hooks in these fossils. This very specific structure is well known in modern larvae of Ptilodactylidae (toed-winged beetles). Therefore, the fossils are interpreted as larvae of Ptilodactylidae. Both types of here reported elateriform larvae represent the first fossil record of larvae of their respective groups. It is well known that larval morphology does not evolve in concert with adult morphology, and a modern-type morphology of the one may precede that of the other. Hence, the new fossils are important indicators of the appearance of the modern larval morphologies of their respective lineages. We also briefly discuss the fossil record of larvae of Elateriformia (of which Elateridae and Ptilodactylidae are ingroups) in general.

Exposure of Beauveria bassiana from different sites to changes in behaviour and mortality of oil palm beetle larvae: Oryctes rhinoceros

The potential of Beauveria bassiana as a biological control agent for Oryctes rhinoceros is still rarely reported. The objective of the research was to analyse the behaviour and mortality of O. rhinoceros larva due to exposure to several of B. bassiana. The research method used the Completely Randomized Design and analysis with 5% Tukey’s test. The results showed that B. bassiana form different sites had the potential to be developed as an effective biological control product in controlling O. rhinoceros as a part of novelty to explore the biodiversity of native biological control in Indonesia. Larvae of O. rhinoceros that were exposed to and infected with B. bassiana experienced changes in movement activity and decreased appetite as well as differences in cuticle colour, the initially limp body will turn stiff while the cuticle colour will change and the next symptom will be white mycelium growth which was proven by the SEM. The B. bassiana from Jember 1 had the highest mortality rate of 37.5% at 30 days after application even though it had the lowest spore density. These results indicate something new and require further study regarding the toxin content of each B. bassiana from different sites.

Assessment of Boll Weevil Susceptibility to Isocycloseram and Ethiprole and Differential Toxicity to Natural Enemies.

Insecticides efficient against the target species while conserving natural enemies in the agroecosystem are required for IPM. With the imminent discontinuation of fipronil, a broad-spectrum insecticide, ethiprole, which belongs to the same group as phenylpyrazole (2B), and isocycloseram, a novel isoxazoline insecticide with distinct mode of action (30), provide options for controlling boll weevil. The susceptibility of the boll weevil, Anthonomus grandis grandis (Boh.), and two natural enemies [Eriopis connexa (Germar) and Bracon vulgaris Ashmead] to these insecticides were studied. Furthermore, the survival and biological traits of the lady beetle, E. connexa, exposed to fipronil, isocycloseram, and ethiprole were assessed. The LC50s values for fipronil, ethiprole, and isocycloseram for A. grandis grandis were 2.71, 0.32, and 0.025mg a.i./L, respectively; 0.86, > 200, and 3.21mg a.i./L for E. connexa; and 2.31, 592.94, and 0.18mg a.i./L for B. vulgaris, respectively. The recommended rates of ethiprole did not cause mortality in adult lady beetles, although fipronil and isocycloseram were highly toxic. Lady beetle larvae and adults survived more than 80% when exposed to dried residues of ethiprole, but less than 10% when exposed to fipronil and isocycloseram. Lady beetle larvae development, reproduction, and predation rates of adults were similar between ethiprole and the control group. Although fipronil and ethiprole belong to the same insecticide group, the difference in toxicity to boll weevils and natural enemies is presented and discussed. Ethiprole was more toxic to boll weevils than to its parasitoid and lady beetle, and isocycloseram was highly toxic to all three species.

Ethnoentomology: socio-cultural aspects of the acceptability of insects as food by the urban population of Brazzaville city in Republic of the Congo

The present article addresses an aspect of entomophagy for the current urban population of Brazzaville city, capital of the Republic of the Congo. It recalls, firstly, the interest in entomophagy, which was emphasised by the FAO in 2013. Concerning the Brazzaville city, cultural and religious practices of the current inhabitants attract attention and have in particular been analysed, as well as their sociodemographic and dietary characteristics. Caterpillars, orthopterans, termites and beetle larvae were discussed in particular. In this study, the questionnaire was used as a data collection tool. The results showed that the acceptability or not of insects as food by the non-native populations of Brazzaville depends on their country of origin, their ethnicity and their length of residence (p<0.001). Insect consumption is highly positively correlated with the presence of preferred insects from the country of origin on the market (r=0.837; p<0.001). There is a very significant negative correlation between the number of years of residence in Brazzaville and the consumption of insects by non-native populations (r=-0.306; p<0.001). People who consumed insects in their country of origin either maintained the habit of insects’ consumption (59.50%), or lost this habit (13.90%). The others (3.00%) who do not consume insects in their region have integrated entomophagy into their eating habits following cultural contact with entomophagous populations. Therefore, cultural contact has a negative or positive influence on entomophagy.

The freeze-avoiding mountain pine beetle (Dendroctonus ponderosae) survives prolonged exposure to stressful cold by mitigating ionoregulatory collapse.

Insect performance is linked to environmental temperature, and surviving through winter represents a key challenge for temperate, alpine and polar species. To overwinter, insects have adapted a range of strategies to become truly cold hardy. However, although the mechanisms underlying the ability to avoid or tolerate freezing have been well studied, little attention has been given to the challenge of maintaining ion homeostasis at frigid temperatures in these species, despite this limiting cold tolerance for insects susceptible to mild chilling. Here, we investigated how prolonged exposure to temperatures just above the supercooling point affects ion balance in freeze-avoidant mountain pine beetle (Dendroctonus ponderosae) larvae in autumn, mid-winter and spring, and related it to organismal recovery times and survival. Hemolymph ion balance was gradually disrupted during the first day of exposure, characterized by hyperkalemia and hyponatremia, after which a plateau was reached and maintained for the rest of the 7-day experiment. The degree of ionoregulatory collapse correlated strongly with recovery times, which followed a similar asymptotical progression. Mortality increased slightly during extensive cold exposures, where hemolymph K+ concentration was highest, and a sigmoidal relationship was found between survival and hyperkalemia. Thus, the cold tolerance of the freeze-avoiding larvae of D. ponderosae appears limited by the ability to prevent ionoregulatory collapse in a manner similar to that of chill-susceptible insects, albeit at much lower temperatures. Based on these results, we propose that a prerequisite for the evolution of insect freeze avoidance may be a convergent or ancestral ability to maintain ion homeostasis during extreme cold stress.

Coccinellid predation efficiency on Aphis gossypii (Hemiptera: Aphididae) under laboratory conditions.

In this study, we investigated the biological aspects and predation efficiency of 3 aphidophagous ladybird beetles, Coccinella novemnotata, Hippodamia variegata, and Coccinella septempunctata, on the cotton aphid, Aphis gossypii, reared on cucumber plants (Cucumis sativus L. cultivar barracuda) under laboratory conditions. The developmental periods of C. novemnotata, H. variegata, and C. septempunctata were observed to be 16.00 ± 0.25, 16.00 ± 0.25, and 20.58 ± 0.40 days, respectively. The larvae of these ladybird beetles consumed an average of 218.93 ± 8.86, 254.77 ± 8.86, and 537.36 ± 10.49 aphids, respectively. Fourth-instar larvae were particularly efficient, consuming 53.68%, 52.68%, and 52.64% of total aphids for C. novemnotata, H. variegata, and C. septempunctata, respectively. Adult emergence rates were promising, with 91.67%, 100.00%, and 92.86%, accompanied by sex ratios of 63.64%, 53.84%, and 61.54%, respectively. Notably, a single female of C. novemnotata, H. variegata, and C. septempunctata consumed an average of 2,215.30, 2,232.00, and 3,364.50 aphids, respectively, over its lifespan. Coccinella septempunctata demonstrated the highest predation efficiency among the 3 species, suggesting its potential for biological control of A. gossypii in both open fields and greenhouses, promoting sustainable agricultural practices.

A new fungal entomopathogen has potency as a biocontrol agent of longhorn beetle larva, Osphranteria coerulescencs

A new fungal entomopathogen has potency as a biocontrol agent of longhorn beetle larva, Osphranteria coerulescencs

Food web structures of irrigated rice fields estimated from carbon and nitrogen stable isotopes: Special reference to the role of filamentous green algae as a food resource of aquatic consumers

AbstractRice fields are characterized by high algal production and dense mats of filamentous green algae, and they function as habitats for various aquatic organisms. However, how algal production supports the secondary production of aquatic consumers in rice fields has not been assessed. Herein, aquatic food web structures in two adjacent rice fields in northeastern Japan were examined using carbon and nitrogen stable isotope analyses. Filamentous algae often showed higher δ13C values (mean, −23.1‰ to −21.4‰) than other organic matter sources, including particulate organic matter, benthic microalgae, and soil organic matter (−30.1‰ to −25.4‰). A δ13C‐based isotopic mixing model estimated that among 19 taxa of herbivores and omnivores, most taxa depended on filamentous algae‐derived carbon (ca. >30%). Particularly, Peltodytes intermedius larvae, a specialist feeder for filamentous algae, showed the highest reliance (mean, 66.7%–80.0%). The microcrustacean, Ostracoda sp. also utilized a diet consisting of a substantial proportion of filamentous algae‐derived carbon (57.6%). Seven out of 10 carnivorous taxa showed reliance on filamentous algae‐derived carbon by >30%. Particularly, larvae of beetles (Berosus sp., Enochrus sp., and Hydrochara affinis) showed the highest reliance (40.2%–44.3%). They could assimilate filamentous algae‐based carbon by consuming herbivores, such as P. intermedius. Because fresh filamentous green algae were eaten less by aquatic consumers, the herbivores could consume decomposed filamentous algae rather than fresh ones. Our results suggest that filamentous algae are one of the major organic matter sources supporting secondary production in rice field food webs.

Harnessing the potential of Citrus natsudaidai: An attractant for Melanotus senilis larvae

AbstractClick beetle larvae have been observed to cause crop damage in various regions worldwide; however, accurate prediction of plant damage is hindered by their subterranean life cycle and the associated challenges in sampling. Melanotus senilis, a beetle belonging to the subfamily Elaterinae (tribe Melanotini) within the family Elateridae, is a destructive agricultural pest that harms maize, hops, and ginger. Our study presents novel evidence indicating the attraction of M. senilis larvae to Citrus natsudaidai (Japanese name “Natsumikan” or “Natsudaidai”). Through a field experiment involving different citrus fruits, namely natsumikan, oranges, and grapefruits, we found that C. natsudaidai attracted the highest number of M. senilis larvae. Furthermore, in a separate experiment in which C. natsudaidai and potatoes were placed in the field, C. natsudaidai significantly outperformed potatoes in attracting M. senilis larvae. These findings suggest that C. natsudaidai fruit placed on the soil surface attracts M. senilis larvae. C. natsudaidai fruits used in this study were sourced from those that remained unharvested until August. Therefore, it is possible that the C. natsudaidai fruits used for comparison were more mature than the citrus fruits used in this study. It is possible that the ripening of C. natsudaidai may have led to changes in CO2 and ethylene emissions, potentially attracting a greater number of M. senilis larvae. Further research is required to explore these aspects in detail.

Physicochemical and Functional Properties of Edible Dung Beetle Larvae (Scarabaeus satyrus) Flours and Oils and their Significance in Human Nutrition

The potential of edible insects in alleviating the nutritional challenges facing humans has led to an increased interest in their utilization. Edible insects contain substantial amounts of protein and fats, which are very important macronutrients that confer useful functional and physicochemical properties to foods. However, the functional properties of these nutrients have not been given sufficient attention, limiting their use as ingredients in diets and food products. Processing of insects converts them into an ingredient that can be added to various foods, improving their acceptability in terms of flavor, taste, and nutritional content. Popular processing methods for edible insects include frying, boiling, oven drying, roasting, smoking, and toasting. These thermal treatments reduce the insect water content, enabling them to be milled into powders. This study set out to investigate the fatty acid profile, protein digestibility, and physicochemical and functional properties of powders and oils of edible dung beetle (Scarabaeus satyrus). The dung larvae were collected from three counties in Western Kenya. They were cleaned and subjected to drying and milling, then analyzed. Results indicated that protein digestibility ranged between 64.27-70.03%. The dominant unsaturated fatty acid was Oleic (45.71±2.45%), while the main saturated fatty acid was Lauric (45.43 ±0.8%). The saponification value of the oils ranged between 127.94 -130.17 mgKOH/g oil, Acid value (41.96-44.11 mg KOH/g oil), peroxide value (4.23-3.8 Meq.thio / kg sample), refractive index (1.41-1.44/25ºC) and Iodine value (77.89-88.02 g I/100g). Functional properties of the powders showed high lipophilic (332.45±19.73%) and moderate (1.11±0.14 ml/g) hygroscopic tendencies in toasted samples from Bungoma and Siaya Counties, respectively. Emulsifying capacity varied between 80.85%-82.53%, while emulsifying stability ranged from 80.85%-81.33%. These findings show that the edible Scarabaeus satyrus can provide unsaturated fatty acids and can be a good ingredient in foods as an alternative to conventional cuisines

Screening and Isolation of Xylanolytic Filamentous Fungi from the Gut of Scarabaeidae Dung Beetles and Dung Beetle Larvae.

Research on renewable biotechnology for renewable biofuel applications has reached new heights. This is highlighted by extensive biomining for novel enzymes to reduce the production costs from animal and insect gut microbiomes. This study explored the diversity and composition of hemicellulolytic fungi in the gut microbiota from dung beetles of the family Scarabaeidae (Pachylomerus femoralis, Anachalcos convexus and Euoniticellus intermedius). Two hundred and twenty-two filamentous fungi were isolated, purified and identified using rDNA sequencing of the ITS and D1/D2 regions. The fungal isolates were assigned to 12 genera and 25 species. Fungi associated with the genus Aspergillus was in abundance, with Hypocrea lixii predominantly isolated. Isolates that produced more than 3 U/mL of xylanase activity were evaluated further. The highest xylanase activity was of 23.6 and 23.5 U/mL for L1XYL9 (E. intermedius larvae) and Hypocrea lixii AB2A3 (A. convexus), respectively. Phylogeny of the fungal strains with xylanolytic activity was analysed using ITS rDNA sequences and revealed close genetic relatedness between isolates from the different dung beetle species. Fungal genera commonly found in the gut of both adult beetles and larvae included Aspergillus, Hypocrea, Talaromyces and Penicillium. The results obtained in this study suggest that the gut of Scarabaeidae dung beetles in South Africa is a rich source of xylanolytic fungi.

Redescription of three pinworms of the genus Cephalobellus Cobb, 1920 (Nematoda: Oxyuridomorpha: Thelastomatidae) from scarab beetle grubs from Hungary

Larvae of European rose chafer Cetonia aurata (Linnaeus, 1758) and cockchafer Melolontha sp. beetles were collected in Hungary for parasitological study. Intestinal examination revealed the presence of three well-known thelastomatid nematodes belonging to the genus Cephalobellus Cobb, 1920. We report for the first-time Cephalobellus cuspidatum (Rudolphi, 1814) Leibersperger, 1960, C. osmodermae Leibersperger, 1960, and C. potosiae Leibersperger, 1960 in Hungary, all found in scarab beetle larvae. Due to incomplete original descriptions, a comprehensive redescription with detailed morphological data is presented. Additionally, an identification key for closely related Cephalobellus, Thelastoma and Severianoia species infesting scarab beetles worldwide is provided. Newly generated 18S and 28S rDNA gene sequences of C. osmodermae place it as one of the early branches within Thelastomatidae.