ABSTRACT
Beetles (Coleoptera) are known to constitute forensic evidence in medico-legal investigations as their presence can be used to date human remains in almost all decomposition stages. Many forensic studies focus on the successional colonization pattern of flies (Diptera); however, beetles have not so far been studied extensively for this aspect. A beetle of the genus Afromorgus Scholtz, 1986, A. chinensis (Boheman, 1858) (Scarabaeoidea: Trogidae), was found beneath a late decaying rabbit carcass at Paya Indah Wetland, Dengkil, Malaysia, for the first time. Both genus and species are already known to occur in Malaysia from literature.
Subject(s)
Coleoptera , Diptera , Forensic Entomology , Animals , Rabbits , Humans , Postmortem Changes , Forensic Sciences , Entomology , Cadaver , Feeding BehaviorABSTRACT
Simulium takahasii (Rubtsov), which was originally described from Japan, and recorded from Korea and China, is the first among the 19 species of the subgenus Wilhelmia Enderlein recorded from East Asia. It is striking in mating, blood-feeding and ovipositing in captivity and in experimentally transmitting Dirofilaria immitis (Leidy) and Brugia pahangi (Buckley & Edeson), and it is a severe biter of cattle and horses, rarely of humans. Nevertheless, updated information about its morphological characteristics was lacking, making comparisons with related species described from China difficult, since species of the subgenus Wilhelmia are almost indistinguishable from one another, in particular, in their female terminalia, male genitalia and most of larval features. In this study, as many morphological characteristics as possible of S. takahasii based on specimens from Japan are redescribed. New information about many features of this species including the length of the female sensory vesicle against the third palpal segment, number of male upper-eye (large) facets, arrangement of the eight pupal gill filaments, presence or absence of tiny dark setae on the dorsum of the larval abdomen and the number of rows and hooklets of the larval posterior circlet will be useful in evaluating the species status of several Wilhelmia species in China including the species regarded as S. takahasii.
Subject(s)
Simuliidae , Humans , Female , Male , Animals , Cattle , Horses , Asia, Eastern , China , Japan , LarvaABSTRACT
Simulium (Gomphostilbia) okinawense Takaoka and S. (G.) tokarense Takaoka, both from the Nansei Islands, Japan, were morphologically reexamined and genetically analysed by using the COI gene sequences. The female, male, pupa and mature larva of the two species are redescribed. Morphological reexamination shows that both species are more similar to species in the S. asakoae species-group than to those in the S. ceylonicum species-group, by having a medium-long female sensory vesicle, yellow tuft hairs (S. (G.) okinawense) or yellow tuft hairs mixed with a few to several dark hairs (S. (G.) tokarense) at the base of the radial vein in the female and male, and medium-long larval postgenal cleft. However, the body of the male ventral plate (viewed ventrally) is parallel-sided (S. (G.) okinawense) or parallelsided or slightly narrowed (S. (G.) tokarense) and not emarginated basally, differing from those of most species in the S. asakoae species-group. Our genetic analysis shows that S. (G.) tokarense is in the S. asakoae species-group, and S. (G.) okinawense formed a separate sister clade with other members of the S. asakoae species-group with high bootstrap support. From the results of morphological and genetic analysis combined, S. (G.) okinawense and S. (G.) tokarense are transferred from the S. ceylonicum species-group to the S. asakoae species-group.
Subject(s)
Simuliidae , Animals , Female , Male , Simuliidae/anatomy & histology , Japan , Islands , Larva/genetics , Pupa/geneticsABSTRACT
@#Simulium (Gomphostilbia) okinawense Takaoka and S. (G.) tokarense Takaoka, both from the Nansei Islands, Japan, were morphologically reexamined and genetically analysed by using the COI gene sequences. The female, male, pupa and mature larva of the two species are redescribed. Morphological reexamination shows that both species are more similar to species in the S. asakoae species-group than to those in the S. ceylonicum species-group, by having a medium-long female sensory vesicle, yellow tuft hairs (S. (G.) okinawense) or yellow tuft hairs mixed with a few to several dark hairs (S. (G.) tokarense) at the base of the radial vein in the female and male, and medium-long larval postgenal cleft. However, the body of the male ventral plate (viewed ventrally) is parallel-sided (S. (G.) okinawense) or parallelsided or slightly narrowed (S. (G.) tokarense) and not emarginated basally, differing from those of most species in the S. asakoae species-group. Our genetic analysis shows that S. (G.) tokarense is in the S. asakoae species-group, and S. (G.) okinawense formed a separate sister clade with other members of the S. asakoae species-group with high bootstrap support. From the results of morphological and genetic analysis combined, S. (G.) okinawense and S. (G.) tokarense are transferred from the S. ceylonicum species-group to the S. asakoae species-group.
ABSTRACT
@#Simulium takahasii (Rubtsov), which was originally described from Japan, and recorded from Korea and China, is the first among the 19 species of the subgenus Wilhelmia Enderlein recorded from East Asia. It is striking in mating, blood-feeding and ovipositing in captivity and in experimentally transmitting Dirofilaria immitis (Leidy) and Brugia pahangi (Buckley & Edeson), and it is a severe biter of cattle and horses, rarely of humans. Nevertheless, updated information about its morphological characteristics was lacking, making comparisons with related species described from China difficult, since species of the subgenus Wilhelmia are almost indistinguishable from one another, in particular, in their female terminalia, male genitalia and most of larval features. In this study, as many morphological characteristics as possible of S. takahasii based on specimens from Japan are redescribed. New information about many features of this species including the length of the female sensory vesicle against the third palpal segment, number of male upper-eye (large) facets, arrangement of the eight pupal gill filaments, presence or absence of tiny dark setae on the dorsum of the larval abdomen and the number of rows and hooklets of the larval posterior circlet will be useful in evaluating the species status of several Wilhelmia species in China including the species regarded as S. takahasii.
ABSTRACT
@#Beetles (Coleoptera) are known to constitute forensic evidence in medico-legal investigations as their presence can be used to date human remains in almost all decomposition stages. Many forensic studies focus on the successional colonization pattern of flies (Diptera); however, beetles have not so far been studied extensively for this aspect. A beetle of the genus Afromorgus Scholtz, 1986, A. chinensis (Boheman, 1858) (Scarabaeoidea: Trogidae), was found beneath a late decaying rabbit carcass at Paya Indah Wetland, Dengkil, Malaysia, for the first time. Both genus and species are already known to occur in Malaysia from literature.
ABSTRACT
The taxonomy of ticks of the subgenus Boophilus has been extensively debated and is often complicated by the high intraspecific variation of morphological features between species. Notably, the cattle tick Rhipicephalus microplus is a species complex consisting of Rhipicephalus annulatus, Rhipicephalus australis and the three mitochondrial clades (A-C) of R. microplus. To gain insight into the taxonomic status of this species complex, we performed morphological and molecular analyses on these cattle ticks across four states in peninsular Malaysia. We morphologically identified 60 males and 104 females of R. microplus, 298 males and 374 females of R. australis, and one R. annulatus male in our field collection, of which the latter two species have never been recorded in Malaysia. However, all three morphologically identified species were molecularly assigned as R. microplus clade A based on the barcoding cytochrome oxidase subunit I (COI) analysis. The discrepancy between morphological and genetic data highlights an urgent need for further exploration and in-depth research into the taxonomic status of these sympatric tick species.
Subject(s)
Cattle Diseases , Coleoptera , Rhipicephalus , Tick Infestations , Animals , Cattle , Cattle Diseases/genetics , Female , Malaysia , Male , Phylogeny , Rhipicephalus/anatomy & histology , Tick Infestations/veterinaryABSTRACT
Simulium (Gomphostilbia) ogatai (Rubtsov) from Japan, the only Palaearctic species in the S. ceylonicum species-group, is morphologically revised. Its female is described for the first time and its male and pupa are redescribed based on specimens from Gifu, Honshu. It is characterized in the female and male by the base of the radius with a tuft of yellow hairs, in the female by the head slightly wider than the thorax, 5.89 times as wide as the greatest width of the frons, and short sensory vesicle 0.21-0.24 times as long as the third palpal segment; in the male by the number of upper-eye (large) facets in 15 vertical columns and 16 horizontal rows, and hind basitarsus spindle-shaped, enlarged, 3.79 times as long as wide, and 0.83 and 1.00 times as wide as the greatest width of the hind tibia and femur, respectively; and in the pupa by the terminal hooks simple and cone-like, and the cocoon with an anterodorsal projection. Taxonomic notes for this species are given relevant to several related species in the Oriental Region, and its assignment to the S. ceylonicum species-group is confirmed.
Subject(s)
Simuliidae , Animals , Female , Japan , Larva , Male , Pupa , Simuliidae/anatomy & histologyABSTRACT
@#The Plasmodium knowlesi secreted protein with an altered thrombospondin repeat (PkSPATR) is an important protein that helps in the parasite’s invasion into the host cell. This protein has been regarded as one of the potential vaccine candidates against P. knowlesi infection. This study investigates the genetic diversity and natural selection of PkSPATR gene of P. knowlesi clinical isolates from Malaysia. PCR amplification of the full length PkSPATR gene was performed on 60 blood samples of infected P. knowlesi patients from Peninsular Malaysia and Malaysian Borneo. The amplified PCR products were cloned and sequenced. Sequence analysis of PkSPATR from Malaysia showed higher nucleotide diversity (CDS p: 0.01462) than previously reported Plasmodium vivax PvSPATR (p = 0.0003). PkSPATR from Peninsular Malaysia was observed to have slightly higher diversity (CDS p: 0.01307) than those from Malaysian Borneo (CDS p: 0.01212). Natural selection analysis on PkSPATR indicated significant purifying selection. Multiple amino acid sequence alignment revealed 69 polymorphic sites. The phylogenetic tree and haplotype network did not show any distinct clustering of PkSPATR. The low genetic diversity level, natural selection and absence of clustering implied functional constrains of the PkSPATR protein.
ABSTRACT
@#Simulium (Gomphostilbia) ogatai (Rubtsov) from Japan, the only Palaearctic species in the S. ceylonicum species-group, is morphologically revised. Its female is described for the first time and its male and pupa are redescribed based on specimens from Gifu, Honshu. It is characterized in the female and male by the base of the radius with a tuft of yellow hairs, in the female by the head slightly wider than the thorax, 5.89 times as wide as the greatest width of the frons, and short sensory vesicle 0.21–0.24 times as long as the third palpal segment; in the male by the number of upper-eye (large) facets in 15 vertical columns and 16 horizontal rows, and hind basitarsus spindle-shaped, enlarged, 3.79 times as long as wide, and 0.83 and 1.00 times as wide as the greatest width of the hind tibia and femur, respectively; and in the pupa by the terminal hooks simple and cone-like, and the cocoon with an anterodorsal projection. Taxonomic notes for this species are given relevant to several related species in the Oriental Region, and its assignment to the S. ceylonicum species-group is confirmed.
ABSTRACT
The efficacy of three groups of insect growth regulators, namely juvenile hormone mimics (methoprene and pyriproxyfen), chitin synthesis inhibitors (diflubenzuron and novaluron), and molting disruptor (cyromazine) was evaluated for the first time, against Aedes albopictus Skuse (Diptera: Culicidae) larvae from 14 districts in Sabah, Malaysia. The results showed that all field populations of Ae. albopictus were susceptible towards methoprene, pyriproxyfen, diflubenzuron, novaluron, and cyromazine, with resistance ratio values ranging from 0.50-0.90, 0.60-1.00, 0.67-1.17, 0.71-1.29, and 0.74-1.07, respectively. Overall, the efficacy assessment of insect growth regulators in this study showed promising outcomes and they could be further explored as an alternative to conventional insecticides.
Subject(s)
Aedes , Juvenile Hormones/pharmacology , Mosquito Control/methods , Aedes/drug effects , Aedes/growth & development , Animals , Diflubenzuron/pharmacology , Insect Vectors/drug effects , Insect Vectors/growth & development , Insecticides/pharmacology , Larva/drug effects , Larva/growth & development , Malaysia , Methoprene/pharmacology , Phenylurea Compounds/pharmacology , Pyridines/pharmacologyABSTRACT
Simulium ( Simulium) rufibasis Brunetti originally described from India was once considered a geographic generalist widely distributed in the Oriental Region. In this study, the species previously regarded as S. (S.) rufibasis in Taiwan was morphologically re-evaluated and found to be distinguished in the male and pupa from true S. (S.) rufibasis from India. This new species is described as S. ( S.) hehuanense sp. nov. based on a female, a male and their pupal exuviae in Taiwan. This new species is placed in the S. rufibasis subgroup of the S. tuberosum species-group, and is similar to S. (S.) yamatoense Takaoka, Adler & Fukuda from Japan and Korea, but it is barely distinguished by the slenderer forebasitarsi of the female and male. Another new, related species, S. (S.) xiulinense sp. nov., is described based on a male and its pupal exuviae. This new species is distinguished from S. (S.) hehuanense sp. nov. by the number of male upper-eye (large) facets in 20 or 21 vertical columns and 22 horizontal rows (19 vertical columns and 19 horizontal rows in the latter species), and presence of a pair of dorsolateral shiny spots on male abdominal segment 5 (absence in the latter species). Both new species inhabit streams at high elevations (ca, 2,600 m). They differ from S. (S.) sp. (probably S. (S.) arisanum Shiraki) from Taiwan, of the same subgroup, which breeds in streams at low elevations (433-685 m), by the pupal head and thorax covered with tubercles (bare in the latter species).
Subject(s)
Simuliidae , Animals , Female , Larva , Male , Pupa , Simuliidae/anatomy & histology , Simuliidae/classification , TaiwanABSTRACT
This study aims to examine the efficacy of mosquito mat vaporizers on Aedes aegypti and their associated metabolic detoxication mechanisms. For this purpose, Aedes aegypti (Linnaeus) was collected from nine districts in Selangor, Malaysia and tested with mosquito vaporizing mat bioassays. The same populations were also subjected to biochemical assays to investigate activities of detoxifying enzymes, namely non-specific esterase (EST), glutathione-S-transferase (GST) and mixed function oxidase (MFO). The efficacy of Ae. aegypti on the active ingredients tested in decreasing order were d- allethrin > dimefluthrin > prallethrin with PBO > prallethrin. The results further indicated significant enhancement mean levels of EST, GST and MFO in pyrethroid-resistant populations. The mortality rate of Ae. aegypti in response to pyrethroid active ingredients was associated with MFO activity, suggesting it is an important detoxification enzyme for the populations tested. In view of the presence of resistance against household insecticide products, pyrethroid efficacy on Ae. aegypti populations needs to be monitored closely to ensure the implementation of an effective vector control program in Malaysia.
Subject(s)
Aedes , Insecticides , Mosquito Control/instrumentation , Nebulizers and Vaporizers , Pyrethrins , Animals , Glutathione Transferase , Insecticide Resistance/drug effects , Insecticides/pharmacology , Malaysia , Mosquito Vectors , Pyrethrins/pharmacologyABSTRACT
Susceptibility status of Aedes albopictus (Skuse) sampled from residential areas in Interior, Sandakan and Tawau divisions of Sabah, Malaysia, was evaluated based on the WHOrecommended doses of organochlorine and organophosphate larvicides. To determine susceptibility status, larval bioassays were carried out and post 24-hour mortalities based on WHO resistance classifications were adopted. The results demonstrated that Ae. albopictus larvae were resistant toward 5 out of the 8 larvicides tested. Larvae from all populations were resistant against bromophos, fenitrothion, malathion, temephos and dichlorodiphenyltrichloroethane (DDT), with mortalities ranging from 0.00 to 89.33%. Dieldrin, on the other hand, could induce 100.00% mortalities in all populations, followed by fenthion and chlorpyrifos, with mortalities ranging from 97.33 to 100.00% and 81.33 to 100.00% respectively. Despite most populations exhibiting similitude in their resistance status, larvae from Sandakan exhibited the highest resistance level whereas the lowest level was observed in Keningau. In view of the inadequacy of some larvicides in controlling Ae. albopictus in this study, integrated management such as insecticide rotation or combination of interventions is warranted.
Subject(s)
Aedes , Chlorpyrifos , Insecticide Resistance , Insecticides , Animals , Insecticides/pharmacology , Larva , Malaysia , World Health OrganizationABSTRACT
Canine vector-borne diseases (CVBDs) are increasingly becoming a cause for global concern because of their high morbidity and mortality rates in dogs. However, information on their occurrence in Malaysia is still scanty. In this study, a total of 103 dog blood samples were collected from two animal shelters in central Peninsular Malaysia and tested for the antibodies against Ehrlichia spp., Anaplasma spp., Borrelia burgdorferi, and the antigen of Dirofilaria immitis. Of the 103 tested dogs, 44.7% (46) were found to be seropositive for Ehrlichia spp., 30.1% (31) for Anaplasma spp. and 13.6% (14) for D. immitis. Co-infections of Anaplasma spp. + Ehrlichia spp. (18.5%, 19) were most prevalent, followed by Anaplasma spp. + D. immitis (1.9%; two) and D. immitis + Ehrlichia spp. (1.0%; one). Furthermore, three dogs (2.9%) were also found to have triple infection, testing seropositive for Ehrlichia spp., Anaplasma spp. and D. immitis. The dogs which were found to be seropositive with at least one pathogen were 66.7% (32/51) at shelter A, and 55.8% (29/52) at shelter B. Serological evidence showed that the exposure of major vector-borne diseases in dogs in shelters was relatively high in the surveyed areas. Routine detection and control of vector-borne diseases are of paramount importance for reducing the risk of CVBDs transmission in dogs and humans.
Subject(s)
Antibodies, Bacterial/blood , Antibodies, Helminth/blood , Dogs , Anaplasma , Animals , Borrelia burgdorferi , Dirofilaria immitis , Dogs/microbiology , Dogs/parasitology , Ehrlichia canis , Housing, Animal , Malaysia/epidemiology , Seroepidemiologic Studies , Vector Borne DiseasesABSTRACT
@# Susceptibility status of Aedes albopictus (Skuse) sampled from residential areas in Interior, Sandakan and Tawau divisions of Sabah, Malaysia, was evaluated based on the WHOrecommended doses of organochlorine and organophosphate larvicides. To determine susceptibility status, larval bioassays were carried out and post 24-hour mortalities based on WHO resistance classifications were adopted. The results demonstrated that Ae. albopictus larvae were resistant toward 5 out of the 8 larvicides tested. Larvae from all populations were resistant against bromophos, fenitrothion, malathion, temephos and dichlorodiphenyltrichloroethane (DDT), with mortalities ranging from 0.00 to 89.33%. Dieldrin, on the other hand, could induce 100.00% mortalities in all populations, followed by fenthion and chlorpyrifos, with mortalities ranging from 97.33 to 100.00% and 81.33 to 100.00% respectively. Despite most populations exhibiting similitude in their resistance status, larvae from Sandakan exhibited the highest resistance level whereas the lowest level was observed in Keningau. In view of the inadequacy of some larvicides in controlling Ae. albopictus in this study, integrated management such as insecticide rotation or combination of interventions is warranted.
ABSTRACT
@#This study aims to examine the efficacy of mosquito mat vaporizers on Aedes aegypti and their associated metabolic detoxication mechanisms. For this purpose, Aedes aegypti (Linnaeus) was collected from nine districts in Selangor, Malaysia and tested with mosquito vaporizing mat bioassays. The same populations were also subjected to biochemical assays to investigate activities of detoxifying enzymes, namely non-specific esterase (EST), glutathione-S-transferase (GST) and mixed function oxidase (MFO). The efficacy of Ae. aegypti on the active ingredients tested in decreasing order were d- allethrin > dimefluthrin > prallethrin with PBO > prallethrin. The results further indicated significant enhancement mean levels of EST, GST and MFO in pyrethroid-resistant populations. The mortality rate of Ae. aegypti in response to pyrethroid active ingredients was associated with MFO activity, suggesting it is an important detoxification enzyme for the populations tested. In view of the presence of resistance against household insecticide products, pyrethroid efficacy on Ae. aegypti populations needs to be monitored closely to ensure the implementation of an effective vector control program in Malaysia.
ABSTRACT
@#Simulium (Simulium) rufibasis Brunetti originally described from India was once considered a geographic generalist widely distributed in the Oriental Region. In this study, the species previously regarded as S. (S.) rufibasis in Taiwan was morphologically re-evaluated and found to be distinguished in the male and pupa from true S. (S.) rufibasis from India. This new species is described as S. (S.) hehuanense sp. nov. based on a female, a male and their pupal exuviae in Taiwan. This new species is placed in the S. rufibasis subgroup of the S. tuberosum species-group, and is similar to S. (S.) yamatoense Takaoka, Adler & Fukuda from Japan and Korea, but it is barely distinguished by the slenderer forebasitarsi of the female and male. Another new, related species, S. (S.) xiulinense sp. nov., is described based on a male and its pupal exuviae. This new species is distinguished from S. (S.) hehuanense sp. nov. by the number of male upper-eye (large) facets in 20 or 21 vertical columns and 22 horizontal rows (19 vertical columns and 19 horizontal rows in the latter species), and presence of a pair of dorsolateral shiny spots on male abdominal segment 5 (absence in the latter species). Both new species inhabit streams at high elevations (ca, 2,600 m). They differ from S. (S.) sp. (probably S. (S.) arisanum Shiraki) from Taiwan, of the same subgroup, which breeds in streams at low elevations (433–685 m), by the pupal head and thorax covered with tubercles (bare in the latter species).
ABSTRACT
@#Canine vector-borne diseases (CVBDs) are increasingly becoming a cause for global concern because of their high morbidity and mortality rates in dogs. However, information on their occurrence in Malaysia is still scanty. In this study, a total of 103 dog blood samples were collected from two animal shelters in central Peninsular Malaysia and tested for the antibodies against Ehrlichia spp., Anaplasma spp., Borrelia burgdorferi, and the antigen of Dirofilaria immitis. Of the 103 tested dogs, 44.7% (46) were found to be seropositive for Ehrlichia spp., 30.1% (31) for Anaplasma spp. and 13.6% (14) for D. immitis. Co-infections of Anaplasma spp. + Ehrlichia spp. (18.5%, 19) were most prevalent, followed by Anaplasma spp. + D. immitis (1.9%; two) and D. immitis + Ehrlichia spp. (1.0%; one). Furthermore, three dogs (2.9%) were also found to have triple infection, testing seropositive for Ehrlichia spp., Anaplasma spp. and D. immitis. The dogs which were found to be seropositive with at least one pathogen were 66.7% (32/51) at shelter A, and 55.8% (29/52) at shelter B. Serological evidence showed that the exposure of major vector-borne diseases in dogs in shelters was relatively high in the surveyed areas. Routine detection and control of vector-borne diseases are of paramount importance for reducing the risk of CVBDs transmission in dogs and humans.
ABSTRACT
@#Simulium (Simulium) contractum Takaoka from Sulawesi, Indonesia was known only as the pupa. Its female, male and mature larva are described for the first time. The tentative assignment of this species in the Simulium dumogaense species-group is confirmed by the adult characters including the female and male genitalia. The female and male of this species are similar to those of Simulium (Simulium) tumpaense Takaoka & Roberts but are distinguished by the yellowish femora.