Entomologi forensik dapat ditakrifkan sebagai pengetahuan mengenai serangga yang berkait rapat dengan bangkai terutamanya manusia, dengan tujuan ia dapat digunakan dalam penentuan jangka masa pascakematian. Jangka masa pascakematian (PMI) dapat ditentukan dengan mengambil kira spesies serangga dan peringkat perkembangan setiap spesies tersebut. Oleh kerana penentuan jenis spesies memerlukan serangga berkembang ke peringkat dewasa dan ini mengambil masa yang lama, maka objektif utama kajian ini adalah untuk mengoptimumkan suhu dan kelembapan terhadap perkembangan serangga dengan menggunakan larva Chrysomya megacephala sebagai spesimen. Larva C. megacephala dipindahkan ke dalam bekas khas, kemudiannya dimasukkan ke dalam pengeram yang telah dilaraskan suhunya kepada 27, 30, 33, 36 dan 39°C. Selepas menentukan suhu optimum perkembangan larva, aras kelembapan relatif ditentukan. Ini dilakukan dengan menentukan tempoh masa yang diperlukan untuk mengembangkan telur C. megacephala hingga ke peringkat dewasa. Untuk itu aras kelembapan relatif dalam pengeram tersebut dilaraskan kepada 54.2, 57.6, 76.0 dan 67.5% (kawalan). Peringkat perkembangan C. megacephala direkodkan. Hasil yang diperolehi menunjukkan perkembangan C. megacephala lebih pantas pada suhu 33oC berbanding suhu-suhu lain yang digunakan. Aras kelembapan relatif yang optimum juga telah dikenal pasti iaitu pada 76.0%. Dengan menggunakan keduadua data didapati keseluruhan peringkat perkembangan C. megacephala iaitu daripada peringkat telur hingga dewasa dapat dipendekkan daripada 8 hingga 9 hari kepada 5 hari.
The net-winged beetle genus Alyculus Kasantsev is reported from Peninsular Malaysia for the first time and a new species, A. malaypeninsularis sp. nov., is described and illustrated. An expanded identification key to Alyculus males is provided and the biology and distribution of the species are discussed.
Three species have been recognized in the genus Geoparnus Besuchet, 1978, all collected by sifting ground debris from tropical rainforests of Malaysia. The new species Geoparnus loebli sp. nov. is described; morphological similarities to known species G setifer Besuchet, 1978 and G rhinoceros Kodada, Jach, Ciampor Jr & (Camporova-Zat'ovicova, 2007 are discussed. Habitus of adult, male and female genitalia as well as other diagnostic characters are illustrated.
The diversity of beetle assemblages in different habitat types (primary forest, logged forest, acacia plantation and oil palm plantation) in Sabah, Malaysia was investigated using three different methods based on habitat levels (Winkler sampling, flight-interception-trapping and mist-blowing). The overall diversity was extremely high, with 1711 species recorded from only 8028 individuals and 81 families (115 family and subfamily groups). Different degrees of environmental changes had varying effects on the beetle species richness and abundance, with oil palm plantation assemblage being most severely affected, followed by acacia plantation and then logged forest. A few species became numerically dominant in the oil palm plantation. In terms of beetle species composition, the acacia fauna showed much similarity with the logged forest fauna, and the oil palm fauna was very different from the rest. The effects of environmental variables (number of plant species, sapling and tree densities, amount of leaf litter, ground cover, canopy cover, soil pH and compaction) on the beetle assemblage were also investigated. Leaf litter correlated with species richness, abundance and composition of subterranean beetles. Plant species richness, tree and sapling densities correlated with species richness, abundance and composition of understorey beetles while ground cover correlated only with the species richness and abundance of these beetles. Canopy cover correlated only with arboreal beetles. In trophic structure, predators represented more than 40% of the species and individuals. Environmental changes affected the trophic structure with proportionally more herbivores (abundance) but fewer predators (species richness and abundance) in the oil palm plantation. Biodiversity, conservation and practical aspects of pest management were also highlighted in this study.
The synchronous firefly genus Pteroptyx Olivier is reassessed from morphological, molecular, and habitat perspectives in Malaysia, and includes some reliably associated females described from morphological features and internal female reproductive anatomy. Phylogenetic analyses using combined morphological and molecular data (where available) for 158 taxa supported all the major features of the existing taxonomic categories within the Indopacific Luciolinae. They revealed a distinct Pteroptyx clade as a morphologically variable genus with Poluninius selangoriensis Ballantyne being newly synonymised with Luciola testacea Motschulsky, the type species, which is redescribed from the type series. Pteroptyx gelasina Ballantyne was shown to be distinct and three of the four morphological subdivisions within Pteroptyx malaccae (Gorham) considered useful. A new species Pt. balingiana Jusoh sp. nov. is described from Sarawak. A second specimen of Pt. gombakia Ballantyne is described and figured. Some females were reliably associated with identified males by molecular data, but investigation of their morphology showed consistent features that were for the most part not useful for species delineation, which still relies on association with the males and colour patterns. All females investigated had bursa plates.Habitat details for most Pteroptyx revealed an association with a riparian environment likely to support mangroves but not necessarily an obligatory association with mangroves or any particular species. Pteroptyx galbina Jusoh was found up to 30 km from the sea, and Pt. bearni Olivier displays in a variety of flowering plants alongside rivers, including mangroves.Keys to species and diagnoses of all species with coloured plates are given.
A new species of firefly (Coleoptera: Lampyridae) Pygoluciola dunguna Nada sp. nov. is described from males and reliably associated females, collected mainly from lowland dipterocarp forests of Peninsular Malaysia at elevations below 300 m a.s.l. This species is found to be terrestrial, flying at low heights between 10-15 m above ground in between the herbaceous plants. Males are intermediate between the two types of Pygoluciola Wittmer known until now. A list of species, and a key to males and known females of Pygoluciola is given. The female bursa has paired elongate hook like bursa plates.
The pselaphine genus Sathytes Westwood is represented in Borneo by a single species. In this paper we describe four new species: S. borneoensis sp. nov., S. liuyei sp. nov., S. larifuga sp. nov., and S. shihongliangi sp. nov. All new species were collected by light traps in Sabah, and show unique combinations of male sexual characters that lead to ready species discriminations. A key to Sathytes species from Borneo is appended.
Four new species of Grouvellinus Champion, 1923 with very long median pronotal carina are described from China: G. hongkongensis sp. nov. (Guangdong, Guangxi, Hong Kong), G. longiusculus sp. nov. (Jiangxi), G. mediocarinatus sp. nov. (Fujian, Guangdong), and G. robustus sp. nov. (Anhui). These species are obviously closely related to G. bishopi Jäch, 1984 described from Malaysia (Selangor). The latter is here recorded for the first time from Kedah and Perak (Malaysia). Habitus photographs, detailed line drawings of the male genitalia, as well as a key to the males of the species of Grouvellinus with very long median pronotal carina are provided.
The Agrilus purpurifrons species-group comprising twelve species from the Oriental region is defined and revised. A key to species is provided and complemented with illustrations of habitus and genitalia. Three new species are described: Agrilus cameronius sp. nov. (Malaysia); A. puncak sp. nov. (Indonesia); and A. vendibilis sp. nov. (Indonesia). The following taxonomic changes are proposed: the specific names lacroixi Obenberger, 1936 syn. nov. and chapaensis Descarpentries Villiers, 1967 syn. nov. are junior synonyms in the synonymy of A. morio Kerremans, 1895; the name rousselatae Baudon, 1968 stat. rev. is removed from the synonymy of A. lacroixi Obenberger, 1936 and revalidated as the specific name of A. rousselatae Baudon, 1968.
The monotypic genus Chandleriella Hlaváč, 2000 is reported from China for the first time, and a new species, C. yunnanica Yin, sp. nov. (type locality: Lincang, Yunnan), is described. It can be readily separated from C. termitophila (Bryant, 1915) of Sarawak by possessing a conspicuously modified antennomere 11 of the male.
The phylogenetic relationships of 26 Australian species of Scirtes Illiger, Ora Clark and Exochomoscirtes Pic (Scirtidae) were investigated using adult morphology, particularly male and female genitalia, larval morphology and molecular data from the mitochondrial cytochrome c oxidase subunit I (COI) gene and the nuclear genes elongation factor 1-alpha (EF1- a) and topoisomerase I (TOP1). Four species of Scirtes and one of Ora from Europe, Southeast Asia and Japan were included. The genus Scirtes is shown to be paraphyletic with respect to the genera Ora and Exochomoscirtes. Australian Scirtes were shown to belong to four species groups: Scirtes elegans group (Yoshitomi 2009); S. helmsi group (Watts 2004); S. japonicus group (Nyholm 2002); and S. haemisphaericus group (Yoshitomi 2005). The prehensor and bursal sclerite of 15 species are illustrated as well as habitus illustrations of S. zwicki sp. nov. and S. albamaculatus Watts. Three new species from Australia are described: Scirtes lynnae, S. zwicki and S. serratus spp. nov. Scirtes nehouensis Ruta & Yoshitomi 2010 is synonymised with S. emmaae Watts 2004. Scirtes pygmaeus Watts, 2004 is synonymised with S. pinjarraensis Watts, 2006. Scirtes rutai nom. nov. is proposed as a replacement name for S. beccus Ruta, Kiałka & Yoshitomi, 2014 from Sabah as it is preoccupied by S. beccus Watts, 2004 from Australia.
Palpoxena hajeki sp. nov. from continental Malaysia, characterised by completely reddish brown body and deeply excavated anterior of male head with a pair of large twisted tufts of setae, is described and compared with the similar species. Colour photos of habitus, body details and penis are presented.
A partially skeletonized human corpse was found in bushes in Selangor, Malaysia in June 2020. Entomological evidence was collected during the autopsy and sent to the Department of Medical Microbiology and Parasitology, Faculty of Medicine, Universiti Teknologi MARA (UiTM) for minimum postmortem interval (PMImin) analysis. Standard protocols were applied when processing preserved and live insect specimens of both larval and pupal stages. Entomological evidence revealed that the corpse was colonized by Chrysomya nigripes Aubertin, 1932 (Diptera: Calliphoridae) and Diamesus osculans (Vigors, 1825) (Coleoptera: Silphidae). Chrysomya nigripes was chosen as the PMImin indicator as this fly species is an earlier colonizer compared to D. osculans beetle larvae which their presence is the indicative of late stage of decomposition. For the present case, the pupae of C. nigripes were the oldest insect evidence collected and based on the available developmental data, the estimated minimum PMI was established between 9 and 12 days. It is noteworthy to highlight that this is the first record of D. osculans colonization on a human corpse.
The species of the genus Coeligetes Jacoby, 1884 distributed in Malaysia and Indonesia are revised, illustrated and keyed. New species, C. howardi sp. nov. from Borneo is described. New synonymy Coeligetes submetallica Jacoby, 1884 = C. wilcoxi Mohamedsaid, 1994 (syn. nov.) is proposed. New genus and species Coeligetoides trifurcatus gen. nov., sp. nov. (Malaysia, Brunei, Indonesia and Thailand) is described, illustrated and compared with related genera.
A new genus and species of the subtribe Batrisina from western Sarawak, Bryantinus matangus gen. et sp. n., is described, illustrated, and compared with related taxa. In addition, examination of a small series of batrisine material from Thailand revealed a new country record for Cerochusa cilioceps Yin & Nomura, which was previously known only from the island of Hainan in southern China.
A new species, Megatyrus femoralis sp. n., is described from the Koshi Zone, East Nepal, with major diagnostic features illustrated. Megatyrus masumotoi Nomura, Sakchoowong & Chanpaisaeng, originally described from southwestern Thailand, is recorded from the Noring Timur Mountain, West Malaysia. The above data extends the known range of Megatyrus about 1,200 km to the west, and 870 km to the south.
The effect of sexual selection on species persistence remains unclear. The cost of bearing ornaments or armaments might increase extinction risk, but sexual selection can also enhance the spread of beneficial alleles and increase the removal of deleterious alleles, potentially reducing extinction risk. Here we investigate the effect of sexual selection on species persistence in a community of 34 species of dung beetles across a gradient of environmental disturbance ranging from old growth forest to oil palm plantation. Horns are sexually selected traits used in contests between males, and we find that both horn presence and relative size are strongly positively associated with species persistence and abundance in altered habitats. Testes mass, an indicator of post-copulatory selection, is, however, negatively linked with the abundance of species within the most disturbed habitats. This study represents the first evidence from a field system of a population-level benefit from pre-copulatory sexual selection.
Pselaphinae is a species-rich beetle subfamily found globally, with many exhibiting myrmecophily-a symbiotic association with ants. Pselaphine-ant associations vary from facultative to obligate, but direct behavioral observations still remain scarce. Pselaphines are speciose and ecologically abundant within tropical leaf litter invertebrate communities where ants dominate, implying a potentially important ecological role that may be affected by habitat disturbances that impact ants. In this study, we measured and analyzed putative functional traits of leaf litter pselaphines associated with myrmecophily through morphometric analysis. We calculated "myrmecophile functional diversity" of pselaphines at different sites and examined this measure's relationship with ant abundance, in both old growth and logged rainforest sites in Sabah, Borneo. We show that myrmecophile functional diversity of pselaphine beetles increases as ant abundance increases. Old growth rainforest sites support a high abundance of ants, which is associated with a high abundance of probable myrmecophilous pselaphines. These results suggest a potential link between adult morphological characters and the functional role these beetles play in rainforest litter as ecological interaction partners with ants.
The life history characteristics of the rove beetle Paederus fuscipes Curtis were studied under laboratory conditions using three field strains from Malaysia: Desa Wawasan (DW), Sri Pinang (SP), and Ampang Jajar (AJ). The total development time of immature stages differed significantly among the three strains, especially between DW (17.43 +/- 0.16 d), SP (18.60 +/- 0.19 d), and AJ (18.68 +/- 0.22 d). Adult females and males from DW also exhibited a shorter life span, although the difference among strains was not significant. In terms of fecundity, the numbers of eggs laid per female for DW, SP, and AJ were 121.28 +/- 15.98, 127.30 +/- 18.01, and 147.45 +/- 17.12, respectively. Additionally, because of the shorter life span in DW strain, two apparent peaks in age-stage specific fecundity were detected. The beetles compensated for their shorter life span by increasing their reproductive activity to sustain the progeny in the population. The intrinsic rates of increase (r) of P. fuscipes from DW, SP, and AJ were 0.0773 +/- 0.0046 d(-1), 0.0788 +/- 0.0051 d(-1), and 0.0873 +/- 0.0054 d(-1), respectively; and the net reproduction rates (R0) were 40.09 +/- 7.39 offspring, 45.29 +/- 8.74 offspring, and 42.34 +/- 8.25 offspring, respectively. The mean generation time of P. fuscipes from AJ was 43.08 +/- 1.07 d, which was significantly higher than that from DW (47.95 +/- 1.36 d) and SP (48.57 +/- 1.43 d). The total immature development time of P. fuscipes in this study was shorter than values reported in previous studies.
In view of the increasing and devastating damage by rhinoceros beetle (Oryctes rhinoceros) to coconut palms in the middle of last century, many efforts were made to find an efficient natural control factor against this pest, which could not be controlled by pesticides. The basic procedures of these monitoring programmes are outlined together with the final detection of a virus disease in oil palm estates in Malaysia in 1963. In extensive laboratory studies, the virus was isolated and identified as the first non-occluded, rod-shaped insect virus, morphologically resembling the baculoviruses. Infection experiments clarified the pathology, histopathology, and virulence of the virus and demonstrated that the virus was extremely virulent to larvae after peroral application. These findings encouraged the first pilot release of virus in 1967 in coconut plantations of Western Samoa where breeding sites were contaminated with virus. Surprisingly, the virus became established in the Samoan rhinoceros beetle populations and spread autonomously throughout the Western Samoan islands. As a consequence, there was a drastic decline of the beetle populations followed by a conspicuous recovery of the badly damaged coconut stands. This unexpected phenomenon could only be explained after it was shown that the adult beetle itself is a very active virus vector and thus was responsible for the efficient autodissemination of the virus. The functioning of the beetle as a 'flying virus factory' is due to the unique cytopathic process developing in the midgut after peroral virus infection. Pathological details of this process are presented. Because of the long-term persistence of the virus in the populations, rhinoceros beetle control is maintained. Incorporation of virus into integrated control measures and successful virus releases in many other countries are recorded.