Xylotrupes Gideon Research Articles

Chitosan Xylotrupes gideon encapsulated lemongrass leaf ethanol extract reduce H2O2‐induced oxidative stress in human dermal fibroblast

During phagocytosis, phagocyte cells discharge reactive oxygen species referred to as respiratory bursts, inducing a rise in pro‐oxidants and subjecting the cell to oxidative stress. Such stress is a biological mechanism related to an imbalance in pro‐oxidant/antioxidant homeostasis, which generates toxic reactive oxygen. Encapsulation is a coating process to improve the stability of bioactive compounds from lemongrass extract. Therefore, this study aims to determine the encapsulation activity of lemongrass leaf extract with chitosan X. gideon (LEChXg) to reduce the oxidative stress of fibroblasts. The research used the human dermal fibroblast (HDF) cell line, comprising negative and positive controls and use of LEChXg 100, 200, 300, 400, and 500 µg/mL. HDF cell migration was evaluated by employing the scratch wound healing method and the wound closure was oberseved at 0, 2, 4, 6, and 24 h intervals. The cell proliferation was observed at 24, 48, and 72 h using CCK‐8 at a 450 nm wavelength. The results showed that the observations at 0, 2, and 4 h did not demonstrate any significant difference on the cell migration (p > 0.05) among the groups. However, the wound closure at 4 and 6 h showed a significant difference (p < 0.05) with LEChXg 300 µg/mL. Despite the lack of any significant variation observed up to 24 h, fibroblast subjected to the stressor did not achieve complete closure. The groups treated with LEChXg were more stable in maintaining fibroblast proliferation up to the end of the observation than those with stressors at 24, 48, and 72 h. Fibroblast induced with a stressor was also more stable in maintaining migration and proliferation in groups receiving LEChXg 300 µg/mL.

Struktur umur dan kelimpahan kumbang badak dan kumbang tanduk (Coleoptera: Scarabaeidae) pada perkebunan kelapa sawit di PTPN VIII Unit Parakan Salak, Kabupaten Sukabumi

Kumbang badak (Oryctes rhinoceros L.) dan kumbang tanduk (Xylotrupes gideon L.) (Coleoptera: Scarabaeidae) merupakan dua spesies serangga hama yang biasa ditemukan di perkebunan kelapa sawit di Indonesia. Ketersediaan tempat perkembangbiakan merupakan salah satu faktor yang dapat meningkatkan populasi kedua jenis kumbang tersebut. Penelitian ini bertujuan untuk mengetahui kelimpahan dan struktur umur populasi kumbang badak dan kumbang tanduk pada tempat perkembangbiakan yang ada di perkebunan kelapa sawit. Penelitian dilakukan pada perkebunan kelapa sawit belum menghasilkan dan yang sudah menghasilkan. Hasil penelitian menunjukkan bahwa di perkebunan kelapa sawit PTPN VIII Parakan Salak, Kabupaten Sukabumi, kelimpahan kumbang badak lebih rendah dibandingkan dengan kumbang tanduk (4,47 ± 13,56 berbanding 25,23 ± 16,48 individu/plot). Struktur umur populasi kumbang badak pada breeding site yang berada di lokasi dengan tanaman kelapa sawit yang sudah menghasilkan didominasi oleh larva instar I dan instar II, sedangkan pada lokasi dengan tanaman yang belum menghasilkan tidak ditemukan individu kumbang badak. Sementara, struktur umur populasi kumbang tanduk pada breeding site didominasi oleh fase larva, baik larva instar I, instar II, dan instar III pada kedua lokasi pengamatan. Hasil analisis korelasi menunjukkan rendahnya keterkaitan antara sifat kimia tanah pada breeding site dan kelimpahan kumbang. Karakter kimia tanah yang relatif sama pada breeding site yang ada pada kedua lokasi pengamatan menyebabkan kelimpahan dan struktur umur populasi kumbang badak dan kumbang tanduk pada kedua lokasi pengamatan tersebut tidak jauh berbeda.

The Effect of Horn Beetle Nano Chitosan (<i>Xylotrupes gideon</i>) on the Surface Roughness of Glass-Ionomer Cement

The purpose of this study was to evaluate the effect of adding horn beetle nano chitosan (NCH) to Glass Ionomer Cement (GIC) liquid on surface roughness. The evaluation was done before and after the addition of NCH and from the length of time soaking in artificial saliva. The disc sample with a diameter of 6 mm and a height of 3 mm of total 40 samples were divided into four groups: the GIC control group, GIC modified NCH 0.5%, 1%, and 2%. Each sample was immersed for 24 hours and seven days in artificial saliva. Surface roughness before and after immersion was measured using the Surtronic S-100 Series Surface Roughness Tester. Data analysis was performed using a one-way ANOVA test to determine the effect of adding horn beetle NCH and paired t-test to determine the effect of immersion time on the surface roughness of GIC. Although the highest surface roughness values were found in sample GIC modified NCH 1% (2.51±0.86 for 24 hours) and in sample GIC modified NCH 2% (2.64±0.84 for 7 days), there was no significant differences for both the surface roughness with the addition of NCH (p > 0.05) and the length of immersed time (p > 0.05). As the conclusion, there is no effect of horn beetle nano chitosan to GIC surface roughness. However, the addition of horn beetle NCH presented rougher surfaces after immersion. These experiments can help predict the performance of these materials under clinical conditions.

The Effect of Horn Beetle Nanochitosan (Xylotrupes gideon) Addition on The Hardness of Glass-ionomer Cement


 Introduction: Glass ionomer cement (GIC) is a tooth-colored restorative material that is often used by clinical practitioners because it can release fluoride, is easy to apply to teeth and has minimal preparation techniques. The erosion and moisture-sensitive nature of GIC becomes a problem for a long-lasting aesthetic restoration. Therefore, modifications were made to improve its mechanical properties by adding nanochitosan (NCH) from horn beetle (Xylotrupes gideon).
 Objective: This study aimed to evaluate the effect of adding horn beetle nanochitosan to GIC liquid on the surface hardness and compared with conventional GIC.
 Methods: Forty cylindrical samples of GIC (GC Fuji® IX Extra, Tokyo-Japan, Lot 1912201) with a diameter of 4 mm and a thickness of 6 mm were divided into 4 groups, namely the GIC control group, GIC modified with 0.5wt%, 1wt%, 2 wt% nanochitosan. Each sample was immersed in artificial saliva for 24 hours and 7 days. Surface hardness before and after immersion was tested using a Vickers Microhardness tester (Shimadzu, Japan). The data were analyzed using the Kruskal Wallis test to determine the effect of horn beetle nanochitosan addition and the Wilcoxon Signed-Ranked test to determine the effect of immersion time on GIC surface hardness.
 Results: The Kruskal Wallis statistical test showed significant difference (p<0.05) between the control group and the 24 hours treatment group with the addition of 2wt% nanochitosan, which was the highest surface hardness value (133.1 ± 49.0 HV), followed by 1wt% (127.4 ± 25.5 HV) and 0.5wt% (117.7 ± 22.5 HV). The Wilcoxon Signed-Ranked test statistic also showed a significant difference (p<0.05) between the 24-hour and 7-day immersion time with the surface hardness value at 24 hours immersion greater than 7 days.
 Conclusion: The addition of 0.5wt%, 1wt% and 2wt% horn beetle nanochitosan can increase the GIC surface hardness value.
 
 ABSTRAK
 Pendahuluan: Glass ionomer cement (GIC) merupakan bahan restorasi sewarna gigi yang sering digunakan oleh praktisi klinis karena dapat melepaskan fluor, mudah diaplikasikan pada gigi, dan memiliki teknik preparasi yang minimal. Erosi dan sifat sensitif kelembaban dari GIC menjadi masalah untuk restorasi estetika yang tahan lama. Oleh karena itu, dilakukan modifikasi untuk meningkatkan sifat mekaniknya dengan menambahkan nanokitosan (NCH) dari kumbang tanduk (Xylotrupes gideon).
 Tujuan: Penelitian ini bertujuan untuk mengevaluasi pengaruh penambahan nanokitosan kumbang tanduk ke dalam cairan GIC terhadap kekerasan permukaan dan dibandingkan dengan Semen Ionomer Kaca (SIK) konvensional.
 Metode: Empat puluh sampel silinder GIC (GC Fuji® IX Extra, Tokyo-Japan, Lot 1912201) dengan diameter 4 mm dan ketebalan 6 mm dibagi menjadi 4 kelompok, yaitu kelompok kontrol GIC, GIC dimodifikasi dengan nanokitosan 0,5wt%, 1 wt%, 2wt%. Setiap sampel direndam dalam saliva buatan selama 24 jam dan 7 hari. Kekerasan permukaan sebelum dan sesudah perendaman diuji menggunakan Vickers Microhardness tester. Data dianalisis menggunakan uji Kruskal Wallis untuk mengetahui pengaruh penambahan nanokitosan kumbang tanduk dan uji Wilcoxon Signed-Ranked untuk mengetahui pengaruh waktu perendaman terhadap kekerasan permukaan GIC.
 Hasil: Uji statistik Kruskal Wallis menunjukkan perbedaan bermakna (p<0,05) antara kelompok kontrol dan kelompok perlakuan perendaman 24 jam dengan penambahan nanokitosan 2wt% yang merupakan nilai kekerasan permukaan tertinggi (133,1 ± 49,0 HV), diikuti sebesar 1wt% (127,4 ± 25,5 HV) dan 0,5% (117,7 ± 22,5 HV). Statistik uji Wilcoxon Signed-Ranked juga menunjukkan perbedaan yang nyata (p<0,05) antara lama perendaman 24 jam dan 7 hari dengan nilai kekerasan permukaan pada perendaman 24 jam lebih besar dari 7 hari.
 Kesimpulan: Penambahan nanokitosan kumbang tanduk 0,5wt%, 1% , dan 2wt% dapat meningkatkan nilai kekerasan permukaan GIC.

Bimodal frequency distribution as a criterion for dimorphism in male rhinoceros beetles (Coleoptera: Scarabaeidae: Dynastinae)

AbstractBateson & Brindley (1892) reported that males of the rhinoceros beetle Xylotrupes gideon are dimorphic (i.e. occurring in two distinct forms) with respect to size of the prominent cephalic horn. This claim was based on a comparison of frequency distributions for size of the horn (bimodal) and size of the body (unimodal). Bateson and Brindley did not realize, however, that a bivariate plot of horn length against body size follows a steep, S-shaped trajectory, or that steepness of such a curve—and not dimorphism—underlies the bimodal frequency distribution for size of the horn. The bivariate distribution for horn size vs. body size is continuous and without breaks or interruptions, so the beetles merely exhibit a pattern of allometric variation that went unrecognized at the time. Other species of dynastine beetle also display patterns of sigmoid allometry, but only those with the steepest slopes for the allometric curve also have bimodal frequency distributions for size of the horn. The concept of male dimorphism in X. gideon and other dynastine beetles needs to be reconsidered in the light of findings reported here and elsewhere.

THE EFFECT OF NANOCHITOSAN FROM RHINOCEROS BEETLE (Xylotrupes gideon) TOWARDS GIC SURFACE ROUGHNESS ON CRITICAL pH OF THE SALIVA

Background: Xylotrupes gideon is a harmful insect because it damages the shoots of coconut trees. Xylotrupes gideon has begun to be used in the form of nanochitosan as an alternative in dentistry. The addition of nanochitosan to Glass Ionomer Cement (GIC) material is a modification to improve the properties of GIC, such as surface roughness caused by acidic conditions (critical saliva pH). Nano-sized chitosan is able to increase stability and better absorption, thus inhibit demineralization and increase tooth hardness. This research aimed to investigate the effect of nanochitosan from Xylotrupes gideon on the surface roughness of GIC at critical saliva pH. Method: This research type conducted is an experimental laboratory. Samples of 10 mm (height) x 2 mm (diameter) divided into 2 groups, (A) Unmodified GIC (control group), (B) GIC modified with 10% nanochitosan solution. Samples of the treatment and control group are stored in the incubator at 370C for 1 hour before early surface roughness testing and continued in critical saliva pH (5,5) for 7 days in the incubator before the final test. The surface roughness tester using sutrotonic s-100 series. Result: There was an increase in the surface roughness of conventional GIC by 0.133 µm and GIC nanochitosan by 0.122 µm. The results of the paired t-test before and after immersion in the two groups showed that there was a significant difference (p <0.05) between conventional GIC and nanochitosan GIC. The independent t-test results showed that there was no significant difference (p> 0.05) between the nanochitosan GIC and conventional GIC. Conclusion: Nanochitosan can reduce the surface roughness value of GIC at critical saliva pH, although there is no significant difference to conventional GIC.

The Coexistence of Oryctes rhinoceros L. and Xylotrupes gideon L. (Coleoptera: Scarabaeidae) on Immature Plant in Oil Palm Plantation

Oryctes rhinoceros L. and Xylotrupes gideon L. (Coleoptera: Scarabaeidae) are known to attack palms. O. rhinoceros is a major pest in oil palm while X. gideon is a minor pest found in certain areas with a relatively few numbers. Collecting these beetles by hand picking and trapping are intended to reduce their population. Objectives of this study were to describe an intimacy of shared existence of O. rhinoceros and X. gideon in the oil palm plantation, and to determine the effect of manual collection of the beetles from the decomposing trunks compared to those that were collected using attractant traps. The study was conducted in Asahan Regency, North Sumatera, in Sei Silau PTPN III oil palm plantation. Five traps (2 Ha/trap) containing the pheromone ethyl-4-methyloctanoate were installed randomly at a replanting area of immature palm. Beetle collection was performed daily for 30 consecutive days using two methods, i.e. (a) hand-picking of beetles on the decomposed trunks at surrounding the trap for 2 hour per day, and (b) using pheromone traps. Simple regression and correlation model was used for data analysis. Results showed that coexistence of O. rhinoceros and X. gideon was observed at the breeding sites of decomposing trunks, but not in the traps, and their coexistence showed a weak relationship (r = 0.12). Number of collected O. rhinoceros (221 beetles) was much more than X. gideon (82 beetles). Natural sex ratio (male: female) was approximately 0.5 for O. rhinoceros and 0.4 for X. gideon. Collection of the beetles in the decomposed trunks showed a moderately positive relationship (r = 0.43) with, and significantly influenced (18.73%) to the collection of beetles using pheromone traps.

Pretreatment Of Nano Chitosan And Nano Calcium (X. gideon) In The Application Of Acetic Acid To Enamel Hardness

Background:Chitosan and Calcium are one of the natural polymeric materials obtained from the exoskeleton of Xylotrupes gideon through demineralization, deproteinization and deacetylation processes. Nano chitosan and calcium can inhibit the demineralization process, which is caused by the consumption of acetic acid. This study aims to determine the effect of nano chitosan pretreatment and nano calcium X. gideon on the application of acetic acid toward tooth enamel hardness.Methods:The study used 36 upper teeth premolars divided into 4 groups; the first group was artificial saliva control, the second group was acetic acid application without pretreatment with nano chitosan and nano calcium, the third group was given pretreatment with nano chitosan and the fourth group was given pretreatment with nano chitosan and nano calcium (5:1).Results:The results showed that there were significant differences in all groups both without or with nano chitosan pretreatment and combination nano chitosan and nano calcium X.gideon on the application of acetic acid to hardness of tooth enamel (p

Nutritional Composition of Five Soil-Dwelling Scarab Beetles (Coleoptera: Scarabaeidae) of Assam, India

Proximate and elemental compositions of five soil-dwelling scarabs, Lepidiota mansueta Burmeister, Lepidiota albistigma Burmeister, Xylotrupes gideon (Linnaeus), Catharsius molossus (Linnaeus), and Sophrops iridipennis (Brenske), were assessed. Nutrient content varied widely, and the ranges of proximate contents were as follows: moisture (2.04–2.55%), crude protein (68.54–79.33%), crude fat (4.00–5.50%), crude fibre (5.16–8.28%), total mineral (0.80–4.98%), and carbohydrate (5.28–11.84%). Caloric content was greater in L. mansueta (379.29 kcal) compared to the other four species. The caloric contents of X. gideon (375.54 kcal) and C. molossus (375.19 kcal) were at par but significantly higher than those of L. albistigma (371.04 kcal) and S. iridipennis (361.55 kcal). Sodium content ranged 23.16–35.91 mg/100 g; potassium 14.20–44.33 mg/100 g; calcium 23.33–33.37 mg/100 g; iron 1.41–37.05 mg/100 g; copper 2.01–16.13 mg/100 g; zinc 2.38–15.86 mg/100 g; and manganese 1.09–19.66 mg/100 g. The phenol, flavonoid, and antioxidant activities of L. mansueta and L. albistigma were 4.00 and 6.42 mg catechol equivalent/g, 1.59 and 3.71 mg quercetin equivalent/g, 22.60, and 28.20%(DPPH activity), respectively. Tannin content was higher in L. albistigma (13.30 mg/g) than in L. mansueta (3.24 mg/g). Based on our study, these scarab species can be explored as food supplements and nutraceutical resources in ensuring food security.

Aggregation pheromones for monitoring the coconut rhinoceros beetle (Oryctes rhinoceros) in Jerukwangi Village, Jepara, Indonesia

Oryctes rhinoceros (Coleoptera: Scarabaeidae) is the most serious pest of coconut plantations in Indonesia. Jerukwangi Village is O. rhinoceros attacked one of the coconuts producing villages with more than 75% of the coconut plant population O. rhinoceros. The study aimed to monitor the population and analyze the sex ratio of O. rhinoceros that were attracted to aggregation pheromones in the field. Aggregation pheromones is a chemical compound containing Ethyl 4-methyl octanoate. The pheromone compounds were placed in traps (buckets), hung 2 meters above the ground. The traps were observed, and the beetles trapped were counted every week. In 12 weeks of monitoring, the traps captured 101 insects consist of 90.1% O. rhinoceros and 9.9% other insect species (Rhynchophorus ferrugineus and Xylotrupes gideon). This result indicates the high population of O. rhinoceros in the field. Aggregation pheromone is useful for attracting females. Rhinoceros by 61% and the males by 39%. The advantage of research is it can be used in integrated pest management (IPM) packages for monitoring of beetle population, and removal of beetles.

Efficacy of Rhinoceros Beetle (Xylotrupes gideon) nano chitosan and calcium mouthwash in reducing quantity oral cavity bacteria among elementary school age children

Objective: The level of dental and oral hygiene on elementary school age children is very low, so it can be increasing the incidence of dental and oral diseases which caused by various microorganisms. Mouthwash can keeping dental and oral hygiene, but many commercial mouthwash is still used alcohol as their ingredients, which can be giving side effects, therefore, we still needed used alternative mouthwash, which made from nano chitosan and nano calcium, derived from nature Xylotrupes Gideon. Methods: This is a experimental study with pre and post test control group design using total plate count method. Total is 27 subjects, aged 9 years. Processing data is done by statistical test Chi Square, and one way ANOVA with software of SPSS 23. Results: Results showed that serum concentration of glucose, cholesterol and triglyceride were significantly higher (p ≤ 0.05) when compared with the fluid from three follicles size categories (Small, Medium and large follicles in CL+ and CL- ovaries). The differences between follicle size categories in CL- ovaries were only significant for concentrations of glucose and triglyceride. The FF concentration of glucose and cholesterol in same follicle size categories (Small, Medium and large follicles in CL+ and CL- ovaries) were significant (P ≤ 0.05). Conclusions: Measurement results the quantity of bacteria suggested that decreased of bacteria colonies before and after gargle, on negative control 30%-73%, positive control 33%-100%, the 250ppm concentration is 95% -100%, 500ppm and 750 ppm concentration is 100%. Nanoparticles of chitosan and calcium-based mouthwash formulation from X. gideon has the ability to reduce oral bacterial colonies quantity among elementary school age children. More high concentrations of mouthwash formulations which are used more low quantity of oral bacteria colonies.

Root damage by insects reverses the effects of elevated atmospheric CO2 on Eucalypt seedlings.

Predicted increases in atmospheric carbon dioxide (CO2) are widely anticipated to increase biomass accumulation by accelerating rates of photosynthesis in many plant taxa. Little, however, is known about how soil-borne plant antagonists might modify the effects of elevated CO2 (eCO2), with root-feeding insects being particularly understudied. Root damage by insects often reduces rates of photosynthesis by disrupting root function and imposing water deficits. These insects therefore have considerable potential for modifying plant responses to eCO2. We investigated how root damage by a soil-dwelling insect (Xylotrupes gideon australicus) modified the responses of Eucalyptus globulus to eCO2. eCO2 increased plant height when E. globulus were 14 weeks old and continued to do so at an accelerated rate compared to those grown at ambient CO2 (aCO2). Plants exposed to root-damaging insects showed a rapid decline in growth rates thereafter. In eCO2, shoot and root biomass increased by 46 and 35%, respectively, in insect-free plants but these effects were arrested when soil-dwelling insects were present so that plants were the same size as those grown at aCO2. Specific leaf mass increased by 29% under eCO2, but at eCO2 root damage caused it to decline by 16%, similar to values seen in plants at aCO2 without root damage. Leaf C:N ratio increased by >30% at eCO2 as a consequence of declining leaf N concentrations, but this change was also moderated by soil insects. Soil insects also reduced leaf water content by 9% at eCO2, which potentially arose through impaired water uptake by the roots. We hypothesise that this may have impaired photosynthetic activity to the extent that observed plant responses to eCO2 no longer occurred. In conclusion, soil-dwelling insects could modify plant responses to eCO2 predicted by climate change plant growth models.

Special K: testing the potassium link between radioactive rubidium (86Rb) turnover and metabolic rate

The measurement of (86)Rb turnover recently has been suggested as a useful method for measuring field metabolic rate in small animals. We investigated a proposed mechanism of (86)Rb turnover, its analogy to K(+), by comparing the turnover of (86)Rb in a model insect, the rhinoceros beetle Xylotrupes gideon, fed a diet of plum jam or plum jam enriched with K(+) or Rb(+). The turnover of (86)Rb in the beetles on the K(+) and the Rb(+) diets was higher than that for beetles on the jam diet (F2,311=32.4; P=1.58×10(-13)). We also exposed the beetles to different ambient temperatures to induce differences in metabolic rate ( ) while feeding them the jam and K(+) diets. was higher at higher ambient temperature (Ta) for both jam (F1,11=14.56; P=0.003) and K(+) (F1,8=15.39; P=0.004) dietary groups, and the turnover of (86)Rb was higher at higher Ta for both jam (F1,11=10.80; P=0.007) and K(+) (F1,8=12.34; P=0.008) dietary groups. There was a significant relationship between (86)Rb turnover and for both the jam (F1,11=35.00; P=1.0×10(-3)) and the K(+) (F1,8=64.33; P=4.3×10(-5)) diets, but the relationship differed between the diets (F1,19=14.07; P=0.001), with a higher (86)Rb turnover in beetles on the K(+)-enriched than on the jam diet at all Ta. We conclude that (86)Rb turnover is related to K(+) metabolism, and that this is the mechanism of the relationship between (86)Rb turnover and . Studies relating (86)Rb turnover to should maintain dietary [K] as close as possible to that of natural diets for the most accurate calibrations for free-ranging animals.

Male horn dimorphism, phylogeny and systematics of rhinoceros beetles of the genus Xylotrupes (Scarabaeidae : Coleoptera)

Male horns in several groups of beetles represent a special class of secondary sexual characters in which condition-dependent, alternate developmental programs produce not only a bimodal horn-size distribution, but also discrete male mating behaviours correlated with these alternate phenotypes. While these intrasexual dimorphisms have recently received theoretical and experimental attention concerning how they are produced and modified, less has been focussed on the macroevolutionary behaviour of the ontogenetic mechanism that produces them. The developmental program that produces alternate male morphologies is manifested by a non-linear horn-size allometry that has been noted to vary within and among various taxa according to its shape and position. The purpose of the present study is to produce a preliminary measure of the macroevolutionary behaviour of these allometric characters as a function of defined phylogenetic scale among the rhinoceros beetles of the widespread genus Xylotrupes.A phylogenetic analysis performed herein suggests that Xylotrupes is monophyletic and is composed of six lineages, which are treated as discrete species. The taxon Xylotrupes gideon of previous literature is shown to constitute five species. Explicit rationale, including morphological diagnoses and evidence of reproductive isolation, supports a new, readily testable taxonomic scheme that recognises the following species: Xylotrupes florensis in the Lesser Sunda and Tanimbar Islands, Indonesia; X. meridionalis in Sri Lanka and India; X. ulysses in Sulawesi, Moluccas, Australia, Papua New Guinea and Melanesia; X. pubescens in the Philippines, Sumatra and Sulawesi; X. mniszechi in south-central and south-east Asia and China; and X. gideon in west Malaysia, Borneo and the Indonesian archipelago from Sumatra through the Lesser Sunda Islands. Subspecies are recognised in some of these taxa and are based upon geographic and phylogenetic partitioning.As in other groups of beetles, the sigmoidal allometric relationship of horn size to body size produces bimodal horn-size distributions in the males of all the species of Xylotrupes in which adequate samples were obtained. The present data show that there is more variation in allometric shape but less variation in allometric position in Xylotrupes than in dung beetles of the genus Onthophagus. Moreover, the phylogenetic patterns of variation in horn allometry among the taxa of Xylotrupes indicate that as much variation in allometric position and shape occurs among the subspecies of a single species, X. ulysses, as occurs among the remainder of the species in this genus.Evidence is provided that allometric position in Xylotrupes is responsive to interspecific competition inasmuch as character displacement of body size relative to horn size occurs in newly discerned sympatric populations of X. gideon and X. pubescens zideki. Further, major evolutionary modifications in allometric shape in two subspecies of X. ulysses have apparently occurred independently and involve fundamentally different adaptive mechanisms.These results suggest that modifications in the developmental program that controls male horn dimorphism are a principal feature of diversification in the beetles of the genus Xylotrupes.

Simplified Field Key to Identify Larvae of Some Rhinoceros Beetles and Associated Scarabs (Coleoptera: Scarabaeoidea) in Papua New Guinea Coconut Developments

Abstract In Papua New Guinea, Coleoptera associated with coconuts share or have similar larval breeding sites, which has led to some confusion with their identity. Conclusive identification of these larvae is important before deciding whether it is possible to use biological control measures against them. The available keys are complex and do not take into account simple observable characters that can be used in the field with live specimens. Specimens of the following species were examined: Xylotrupes gideon (L.), Trichogomphus vicinus Dechambre, Oryctoderus latitarsis Boisduval, Oryctes centaurus Sternberg, Oryctes rhinoceros (L.), Scapanes australis Boisduval (Coleoptera, Scarabaeidae, Dynastinae), Dermolepida sp. (Coleoptera, Scarabaeidae, Melolonthinae), Cetoniinae (Coleoptera, Scarabaeidae) and Lucanidae (Coleoptera Scarabaeoidea). A simple key to distinguish 2 important pest species, O. rhinoceros and S. australis, from allied Coleoptera directly in the field is presented, together with drawings an...

Seasonal flight activity of scarab beetles (Coleoptera: Scarabaeidae) associated with sugarcane in southern Queensland

AbstractLight traps were run at six sites for up to 5 years to determine the seasonal flight activity of 14 scarab beetles associated with sugarcane in the Bundaberg, Queensland, district. Four patterns of seasonal activity were detected: brief spring activity by Antitrogus consanguineus and Lepidiota noxia; brief summer activity by Antitrogus parvulus, Lepidiota crinita, Lepidiota frenchi and Lepidiota negatoria; prolonged summer activity by Anoplognathus boisduvalii, Anoplognathus pallidicollis, Anoplognathus porosus, Dasygnathus trituberculatus, Repsimus aeneus and Xylotrupes gideon; and prolonged spring– autumn activity by Metanastes vulgivagus and Neodon pecuarius. The different flight patterns reflect different life cycle strategies to cope with environmental adversity. Females of Antitrogus spp. and L. crinita were rarely caught in traps, while in Anop. boisduvalii, Anop. pallidicollis, Anop. porosus, D. trituberculatus and X. gideon females outnumbered males. Differences between years in numbers of some species with 2‐year life cycles point to large differences in sizes of the two allochronic populations of these species. Differences in species composition between sites reflect differences in soil type.

Morphological variation in adultXylotrupes gideon australicus (Scarabaeidae, Coleoptera, Insecta)

Variation in horn and body size of both sexes of Xylotrupes gideon australicus is normally distributed with no evidence of dimorphism in either sex. This contrasts with that of X. gideon gideon, in which males are dimorphic for horn length, but horn size varies within morphs. Males of X. gideon australicus are generally larger than females, but the distributions of all characters, except tarsal length, overlap considerably. Males have longer legs, presumably to facilitate mating.

Xylotrupes gideoneating bark of apple and pear trees in Northern Thailand

Abstract The occurrence of Xylotrupes gideon on apple and pear in the highlands of Northern Thailand is described. Only the bark of these trees was damaged by X. gideon adults. Initial possibilities for control rely on local Lahu highlanders collecting the beetles for food.

Description of the larva of Chalcosoma atlas (L.) (Coleoptera, Scarabaeidae, Dynastinae) from Malaysia

AbstractThe third-stage larva of Chalcosoma atlas (L.) collected in Malaysia is described, with illustrations, and a key is provided to distinguish larvae of this species from those of Oryctes rhinoceros (L.) and Xylotrupes gideon beckeri Schaufuss, all of which occur in similar breeding sites.

Heteronychus krombeini n.sp. und Eophileurus decatenatus Arrow, neue Arten für die Fauna Ceylons (Coleoptera: Melolonthidae)

AbstractA collection of Melolonthidae: Dynastinae in coll. Nat. Mus., Washington was found to contain the following species: Phyllognathus dionysius Fabr. Dipelicus daedalus Fabr., Oryctes rhinoceros (L.), Blabephorus pinguis Fairm., Xylotrupes gideon meridionalis Prell, Eophileurus singalensis Arrow, E. decatenatus Arrow, which is new for the this fauna, and Heteronychus krombeini n.sp. - Blabephorus pinguis was earlier known from Ceylon in one specimen, a female, only which was described as B. p. ceylonicus Miksic. The only specimen, a male, contained in this collection does not support the idea of a special subspecies in Ceylon.