Despite the public health importance of Culex pipiens pipiens, their resistance to pirimiphos-methyl insecticides has not been explored enough. Late third and early fourth larvae of Culex pipiens pipiens were collected from three localities between 2003 and 2005 in Northern and Southern Tunisia. All bioassays were carried out using pirimiphosmethyl and propoxur insecticides. Populations of Culex pipiens pipiens were susceptible, moderate and resistant to pirimiphos-methyl insecticide. Resistance to this compound ranged from 2.62 in sample # 2 to 19.9 in sample # 1. The moderate resistance (5.25) was recorded in sample # 3. Synergist's tests showed that the resistance to pirimiphos-methyl was not affected by detoxification enzymes. However, biochemical assays showed the involvement of both metabolic (esterases) and target site (insensitive acetylcholinesterase) resistance mechanisms. The highest frequencies of the resistant phenotypes ([RS] and [RR]) (<0.74) were detected in the most resistant samples (#1). Four esterases enzymes including C1 encoded by the Est-1 locus and three esterases encoded by the Ester super locus: A2-B2, A4-B4 (or A5-B5, which has the same electrophoretic mobility) and B12 were detected. The highest (0.61) and the lowest (0.22) frequencies of these esterases were recorded in samples # 1 (Sidi Hcine) and # 2 (El Fahs) which recorded the highest and the lowest level of resistance, respectively. Monitoring of insecticide resistance should be evaluated regularly for management of vector control.
Studies on parasite populations in Antarctic soils are scarce and thus little is known about the threat of these parasites towards either the natural fauna or human visitors. However, human presence in Antarctica, mainly through research and tourism, keeps increasing over time, potentially exposing visitors to zoonotic infections from Antarctic wildlife and environment. Most available literature to date has focused on faecal samples from Antarctic vertebrates. Therefore, this study addressed the possible presence of parasites in Antarctic soil that may be infectious to humans. Soil samples were obtained from five locations on Signy Island (South Orkney Islands, maritime Antarctic), namely North Point and Gourlay Peninsula (penguin rookeries), Pumphouse (relic coal-powered pump house), Jane Col (barren high altitude fellfield) and Berntsen Point (low altitude vegetated fellfield close to current research station). Approximately 10% of the soil samples (14/135) from 3 out of the 5 study sites had parasites which included Diphyllobotridae spp. eggs, Cryptosporidium sp., an apicomplexan protozoa (gregarine), Toxoplasma gondii, helminths (a cestode, Tetrabothrius sp., and a nematode larva) and mites. The presence of parasites in the 3 sites are most likely due to the presence of animal and human activities as two of these sites are penguin rookeries (North Point and Gourlay Peninsula) while the third site (Pumphouse Lake) has human activity. While some of the parasite species found in the soil samples appear to be distinctive, there were also parasites such as Cryptosporidium and Toxoplasma gondii that have a global distribution and are potentially pathogenic.
This paper reports total nematode anthelmintic resistance towards albendazole, fenbendazole, levamisole and ivermectin in a commercial sheep farm located in Terengganu, Malaysia. Faecal Egg Count Reduction Test (FECRT) was conducted on 25 sheep, where five sheep in each group were treated with the respective four anthelmintics based on live bodyweight. The balance of five sheep placed in the control group were not treated with any anthelmintics. At day 13 post-treatment, faecal egg count was conducted and nematode worm egg count reduction percentage was calculated to determine the resistance status towards the respective anthelmintics tested. Results showed that nematodes were resistant to all the anthelmintics tested, namely albendazole, fenbendazole, levamisole and ivermectin with reduction percentage of 87%, 46%, 94% and 68%, respectively. Subsequently, the third stage larvae of Haemonchus contortus and Trichostrongylus colubriformis recovered from post-treatment faecal cultures were subjected to allele-specific polymerase chain reaction (AS-PCR) assay to determine the presence of the benzimidazole resistance gene. This study reports the occurrence of the classical F200Y mutation in the isotype 1 βtubulin gene, for the first time in Malaysia.
Megaselia scalaris (Loew) is a cosmopolitan polyphagous small fly with the ability of exploiting variety of ecological niches. Different life history stages act as detritivore, parasite, and parasitoid of wider spectrum of plant and animal matter under natural and laboratory conditions. Here, for the first time we present the opportunistic parasitism of M. scalaris on Otobius megnini, which act as a vector of Q fever and is capable of causing paralysis, toxic conditions, otoacariasis and otitis in humans and other animals. Tick samples from the ear canals of 14 thoroughbred horses were brought to the laboratory and several days later, larvae of M. scalaris were found feeding on immature stages of O. megnini. When the development was completed pupae were found attached to adult ticks and all nymphs were found dead. This context reveals the capability of M. scalaris surviving on O. megnini and the risk of their invading ear canals of horses.
To characterize the production and larvicidal activity of Xenorhabdus stockiae KUT6 Petroleum ether extracts from Luria Broth and induced Quorum sensing medium containing N-3- oxododecanoyl Homoserine Lactone inducer against dengue vector Aedes aegypti. The Galleria mellonella larvae were reared for the isolation of Steinernema saimkayi symbiont Xenorhabdus stockiae KUT6 from Cucumber field soil sample in NBTA. Then for the extraction of compounds the KUT6 strains were cultured in Luria Broth and Quorum Sensing optimized media using N-3-oxododecanoyl homoserine lactone inducer. The larvicidal activity of Xenorhabdus stockiae KUT6 of petroleum ether extracts were bioassayed against 4th instar Aedes aegypti dengue vector. The maximum rate of mortality were recorded of the samples A-24h, B-48h, C-72h, A1-24h, B1-48h, C1-72h at different concentrations 50 µg/ml, 100 µg/ml and 150 µg/ml respectively for 24h to 72h of exposure treatment. The morphological characteristics of Xenorhabdus stockiae KUT6 in NBTA were red core colonies with blue background surrounded by zone of inhibition. After 24h exposure maximum rate of 100% mortality of Aedes aegypti 4th instar larvae was attained when treated with sample C1-72h 50 µg/ml of the petroleum ether extracts of quorum sensed medium whereas the sample C 72h petroleum ether extracts of KUT6 cultured in Luria broth recorded 100% mortality at 150 µg on 24h exposure indicates enhancement in the product yield. The study assures the use of Xenorhabdus stockiae KUT6 petroleum ether extracts as biocontrol agent could be beneficial for the control of dengue vectors.
Mutant lethal giant larvae (lgl) flies (Drosophila melanogaster) are known to develop epithelial tumors with invasive characteristics. The present study has been conducted to investigate the influence of melatonin (0.025 mM) on behavioral responses of lgl mutant flies as well as on biochemical indices (redox homeostasis, carbohydrate and lipid metabolism, transaminases, and minerals) in hemolymph, and head and intestinal tissues. Behavioral abnormalities were quantitatively observed in lgl flies but were found normalized among melatonin-treated lgl flies. Significantly decreased levels of lipid peroxidation products and antioxidants involved in redox homeostasis were observed in hemolymph and tissues of lgl flies, but had restored close to normalcy in melatonin-treated flies. Carbohydrates including glucose, trehalose, and glycogen were decreased and increased in the hemolymph and tissues of lgl and melatonin-treated lgl flies, respectively. Key enzymes of carbohydrate metabolism showed a significant increment in their levels in lgl mutants but had restored close to wild-type baseline levels in melatonin-treated flies. Variables of lipid metabolism showed significantly inverse levels in hemolymph and tissues of lgl flies, while normalization of most of these variables was observed in melatonin-treated mutants. Lipase, chitinase, transaminases, and alkaline phosphatase showed an increment in their activities and minerals exhibited decrement in lgl flies; reversal of changes was observed under melatonin treatment. The impairment of cognition, disturbance of redox homeostasis and metabolic reprogramming in lgl flies, and restoration of normalcy in all these cellular and behavioral processes indicate that melatonin could act as oncostatic and cytoprotective agents in Drosophila.
The reproductive and developmental characteristics of the nereidid polychaete, Neanthes glandicincta Southern, 1921, commonly recorded in tropical estuaries in the Indo-West Pacific, were examined from Malaysia (the mangrove area of Kuala Ibai, Terengganu) and Thailand (the Lower Songkhla Lagoon) on the east coast of the Malay Peninsula. Epitokous metamorphosis of fully mature males and females and their reproductive swimming behaviour were recorded based on ten Malaysian epitokous specimens, which were collected at night during spring tides in a period of January 2018 to March 2019. Six Thailand epitokes were obtained in February and March 2006 by the laboratory rearing of immature worms. Epitokous metamorphosis is characterised by the enlargement of eyes in both sexes, division of the body into three parts and modification of parapodia with additional lobes in the mid-body of males, and replacement of atokous chaetae in the mid-body by epitokous natatory chaetae, completely in males and incompletely in females. The diameter of coelomic unfertilised eggs in females was 100-140 µm. After fertilisation, each egg formed a jelly layer, inside which embryonic development progressed. Trochophores hatched out of the jelly layer, entering a short free-swimming larval phase followed by demersal life at the early stage of 3-chaetiger nectochaeta one day after fertilisation. Then, the larvae entered benthic life as juveniles, crawling on the bottom, at the late stage of 3-chaetiger nectochaeta two days after fertilisation. The results indicate that N. glandicincta has an annual life cycle, which is usually completed within an estuary with limited larval dispersal ability.
Due to their unusual life cycle that includes parasitic larval and free living adult stages, gnathiid isopods are typically overlooked in biodiversity surveys, even those that focus on parasites. While the Philippines sits within the region of highest marine biodiversity in the world, the coral triangle, no gnathiid species have been identified or described from that region. Here we present the first records of two gnathiid species collected from the Visayas, central Philippines: Gnathia malaysiensis Müller, 1993, previously described from Malaysia, and G. camuripenis Tanaka, 2004, previously described from southern Japan. This paper provides detailed morphological redescriptions, drawings and scanning electron microscope images as well as the first molecular characterisation of both species, Furthermore, a summary of the Central-Indo Pacific Gnathia species is provided.
Goat Warble Fly Infestation (GWFI) is also known as subcutaneous myiasis caused by Przhevalskiana silenus (Diptera: Oestridae). It is widely distributed in tropical and sub-tropical areas of the world. In goats, WFI is usually detected through conventional procedure which underestimated the infestation. The current study was designed to determine the serodiagonsis of GWFI (through IDEXX Hypodermosis serum antibody test) and also aimed to investigate its seroepizootiological profile in Pothwar region, Pakistan from 2013-14. The results showed that average seropositivity (ELISA kit) of GWFI was 18.5% whereas, it was 11% by using conventional procedure (Palpation method) depicting a significant difference (p<0.05). Higher seropositivity (30.8%) was observed in Jhelum district as compared to e Attock district (6%). The L1 larvae were found in September, while nodules start appearing in October to December and last until the end of February. The month wise peaks of optical density (OD) was higher in December which gradually decrease along with the end of winter season. The prevalence of GWFI revealed no significant difference among three host breeds (Jattal, Beetal and Tedy). According to the results, high infestation rate (28%) was observed in young animals of age group < 1 year as compared to old animals (> 2 years). Topographically, hilly areas (33%) provide favourable climatic conditions for the propagating of larval stages. Sex difference showed no significant difference. The seroprevalence varied significantly with respect to age, month, districts and topographical location. The current study proved that serologic diagnosis (commercial ELISA kit) as more sensitive and accurate for timely diagnosis of GWFI than traditional method. The information on the epizootiology of P. silenus in goats of Pothwar region would help in devising effective control strategies.
A field study was conducted at two localities on Pulau Pinang, Malaysia, during two consecutive mango flowering seasons in 2009 to identify variations in the species composition of thrips infesting treated and untreated mango (Mangifera indica L.) orchards. The CO2 immobilisation technique and the cutting method were used to recover different thrips species from mango panicles and weed host plants, respectively. The mango panicles and various weed species within the treated orchard were found to harbour four thrips species from the family Thripidae. These species were identified as Thrips hawaiiensis (Morgan), Scirtothrips dorsalis (Hood), Frankliniella schultzei (Trybom) and Megalurothrips usitatus (Bagnall). The weed species Mimosa pudica, Cleome rutidosperma, Echinochloa colonum, Borreria laevicaulis, Veronia cinerea and Asystasia coromandeliana served as additional hosts to these thrips. Six thrips species were found in the untreated orchard. These species included Thrips palmi (Karny), Haplothrips sp. (Amyot and Serville) and the four thrips species found in the treated orchard. A brief description of the larvae for each genus is provided.
Discarded cigarette butts (DCB) waste occurs worldwide, pollutes landscapes, is unsightly, and results in added debris removal costs. There is, therefore, a great deal of current interest in making use of DCBs in beneficial ways. Despite evidence that DCBs are harmful to water fleas (Daphnia magna), which breed in aquatic environments as do mosquito larvae, their impact on dengue vectors is unknown. We examined whether Aedes albopictus alters its ovipositional responses, larval eclosion, and development in response to presence of DCBs in its habitats. We found oviposition activity in DCB-treated water similar to that of control water and that ovipositional activity in DCB solutions steadily increased over time as those solutions aged to 10 days. Larval eclosion was initially suppressed on day 1 in DCB solution, but increased thereafter to levels similar to control larval eclosion rates. The DCB-water solutions produced significantly higher mortality in both 1st and 2nd instars over control larvae for several days after initial exposure. Mortality rates decreased sharply 3 to 5 days postexposure as DCBs continued to decompose. We found increased survival rates during late development, but daily input of fresh DCBs prevented most young larvae from completing development. Taken together, these observations suggest that decomposing did not deter gravid Ae. albopictus females from ovipositing in treated containers and that DCB solutions had larvicidal effects on early instars. Our results are discussed in the context of DCB use to control container-breeding Ae. albopictus, a competent dengue vector in Asia and other parts of the world.
We conducted the world's first experiments under semi-field conditions (ACL-2 field house) to assess the mating competitiveness of genetically sterile RIDL male mosquitoes (513A strain). The field house is a state-of-the-art, fully-contained trial facility, simulating the living space for a household of 2-4 people in Peninsular Malaysia. Ten genetically sterile RIDL male A. aegypti mosquitoes competed with ten wild type males inside this field house to mate with ten wild type females. Hatched larvae from mated females were screened under a fluorescent microscope for genetic markers to determine if they were fathered by RIDL male or wild type male, and all results were cross-checked by PCR. Two such experiments were conducted, each repeated sufficient number of times. All strains were on a Malaysian lab strain background for the first experiment, while the RIDL males alone were on a recently-colonised Mexican strain background for the second experiment. A total of 52 % of the matings were with RIDL males in the first experiment, while 45 % of the matings were with RIDL (Mexican) males in the second experiment. Statistically, this is not significantly different from 50 % of the matings expected to take place with RIDL males if the latter were as competitive as that of the wild type males. This shows that A. aegypti RIDL-513A has excellent mating competitiveness under semi-field conditions, verifying earlier trends obtained in small lab cages. We also observed high mating compatibility between recently-colonised Mexican RIDL males and lab-reared Malaysian wild type females.
Observation on predation activities of guppies (Poecilia reticulata) on the larvae of three species of mosquito, namely Aedes albopictus, Aedes aegypti, and Culex quinquefasciatus was carried out under laboratory conditions. Male and female guppies were used as predators for predation experiments on the 4th instars of mosquito larvae. The daily feeding rates comparing male and female guppies on mosquito larvae were different; the female guppies consumed more mosquito larvae than male guppies did. The daily feeding rates of female guppies were 121.3 for Ae. aegypti, 105.6 for Ae. albopictus, and 72.3 for Cx. quinquefasciatus. The daily feeding rates of male guppies were 98.6 for Ae. aegypti, 73.6 for Ae. albopictus, and 47.6 for Cx. quinquefasciatus. In terms of prey preference, there was greater preference towards mosquito larvae of Ae. aegypti, followed by Ae. albopictus, and the least preferred was Cx. quinquefasciatus. Male and female guppies consumed more mosquito larvae during lights on (day time) compared with lights off (night time). The water volume, prey species, number of fish predators available, prey densities, and prey's sex also influenced the predation activities.
This revision completes a taxonomic survey of fireflies (Coleoptera: Lampyridae) in the area encompassed by Australia, the Republic of Palau, Federated States of Micronesia, Papua New Guinea, Indonesia (West Irian/Papua), Solomon Islands, New Caledonia, Vanuatu and Fiji. It finalises the taxonomic issues arising from the 1969–70 voyage of the scientific vessel Alpha Helix to New Guinea. The firefly fauna of this area is exclusively Luciolinae. The scope of the revision was extended to include all known Luciolinae genera and certain species from SE Asia, and a phylogenetic analysis of 436 morphological characters of males, females, and associated larvae includes 142 Luciolinae species (Ballantyne & Lambkin 2009, and Fu et al. 2012a). The phylogenetic analyses infer four major groups within the Luciolinae. The monotypic Missimia Ballantyne is sister to all remaining Luciolinae and forms a grade to Aquatica Fu etBallantyne. The large clade of Curtos Motschulsky, Photuroluciola Pic, Colophotia Motschulsky, Poluninius gen. nov., Pyrophanes Olivier, Pteroptyx s. str. Olivier, Medeopteryx gen. nov., Trisinuata gen. nov., and Australoluciola gen. nov.forms a grade to the clade of Luciola s. str. Laporte (including Bourgeoisia Olivier). The monotypic Emeia Fu et al.forms a grade with a clade of Luciola and Pygoluciola Wittmer, sister to a large clade of Convexa Ballantyne, Pacifica gen. nov., Magnalata Ballantyne, Lloydiella Ballantyne, Asymmetricata Ballantyne, Pygatyphella s. str. Ballantyne, Atyphella Olliff, Aquilonia Ballantyne, and Gilvainsula Ballantyne. Luciola is paraphyletic, found in up to six clades across the tree. Together with Luciola, Magnalata, Aquilonia, and Gilvainsula render Atyphella paraphyletic. The new genera described here are all monophyletic and supported in the phylogenetic analyses that also provide evidence for the inclusion of taxa within them. Twenty-three genera including five new ones, and ten new species, are recognised and keys are presented for the males and females. Certain females are characterised by the nature of their bursa plates. Australoluciola gen. nov. is proposed for ten species from Australia and New Guinea, seven transferred from Luciola and three new, with species keyed from males, all of which have an entire light organ in ventrite 7. Aus. anthracina (Olivier), Aus. aspera (Olivier), Aus. australis (F.), Aus. flavicollis (MacLeay), Aus. foveicollis (Olivier), Aus. nigra (Olivier) and Aus. orapallida (Ballantyne) are transferred from Luciola with males assigned to Aus. aspera(Olivier), and a lectotype designated for Luciola foveicollis Olivier; Aus. baduria sp. nov., Aus. fuscamagna sp. nov.,Aus. fuscaparva sp. nov., Aus. japenensis sp. nov. and Aus. pharusaurea sp. nov. are described. Females of Aus. australis and Aus. flavicollis have two pairs of wide bursa plates. The bent-winged fireflies of New Guinea and Australia are removed from Pteroptyx Olivier and assigned to Medeopteryx gen. nov. and Trisinuata gen. nov. Medeopteryx gen. nov. is erected for 17 species including two new; all have ventrite 7 with an entire light organ, trisinuate posterior margin and short posterolateral projections; the following 14 species in which males have deflexed elytral apices are transferred from Pteroptyx Olivier: M. amilae (Satô), M. antennata (Olivier), M. corusca (Ballantyne), M. cribellata (Olivier), M. effulgens (Ballantyne), M. elucens (Ballantyne), M. flagrans (Ballantyne), M. fulminea (Ballantyne), M. hanedai (Ballantyne), M. platygaster (Lea), M. similisantennata(Ballantyne), M. sublustris (Ballantyne), M. tarsalis (Olivier), and M. torricelliensis (Ballantyne). M. clipeata sp. nov. is described. Two species without deflexed elytral apices include M. pupilla (Olivier) which is transferred from Luciola, and M. similispupillae sp. nov. A Lectotype is designated for Luciola pupilla (Olivier). Females of M. corusca(Ballantyne), M. cribellata (Olivier), M. effulgens (Ballantyne), and M. similispupillae sp. nov. have two pairs of wide bursa plates. The second genus including species in which the males have deflexed elytral apices is Trisinuata gen. nov., where all males have light organ in ventrite 7 bipartite and posterolateral projections expanded; it is proposed for eight New Guinean species: T. microthorax (Olivier), T. minor (Ballantyne), T. papuae (McDermott) and T. similispapuae(Ballantyne) are transferred from Pteroptyx Olivier, T. papuana (Olivier) previously known only from a female, has males associated and is transferred from Luciola, and T. caudabifurca sp. nov., T. dimidiata sp. nov. and T. apicula sp. nov. are described. Females of T. similispapuae (Ballantyne) have two pairs of wide bursa plates. Luciola s. str. is defined by scoring the type species L. italica (L), Bourgeoisia Olivier and Lampyroidea (based on its type species syriaca Costa) both of which are submerged into Luciola; Luciola s. str is addressed here from four Pacific Island species: L. hypocrita Olivier, L. antipodum Bourgeois both transferred from Bourgeoisia; L. aquilaclarasp. nov. and L. oculofissa sp. nov. are described. L. oculofissa sp. nov. is the only Luciolinae male known to lack light organs. Females of L. italica and L. hypocrita lack bursa plates.Pacifica gen. nov. is proposed for five species from the Solomon Islands transferred from Pygatyphella(Ballantyne), and which the phylogenetic analysis shows to be distinctive viz. P. limbatifusca (Ballantyne), P. limbatipennis (Pic), P. plagiata (Blanchard), P. russellia (Ballantyne), and P. salomonis (Olivier). A monotypic genus Poluninius gen. nov. is proposed for Pol. selangoriensis sp. nov. from Selangor, Malaysia. The genera Colophotia, Pteroptyx, Pyrophanes, and Pygoluciola are treated in an abbreviated fashion with generic diagnoses, lists of, and keys to, species. Pteroptyx bearni Olivier and P. tener Olivier are characterised from type specimens and female bursae and P. similis Ballantyne is synonymised with P. bearni. Luciola semilimbata Olivier is transferred to Pyrophanes, and Luciola cowleyi Blackburn to Pygoluciola. The following species are treated as species incertae sedis: L. melancholica Olivier, L. ruficollis Guérin-Ménéville. The New Guinean records of Luciola tenuicornis Olivier, L. timida Olivier and Photinus cinctellus Motschulsky are suspect. Fifteen of the species treated here are recognised by flashing patterns. The functions of the terminal abdominal modifications, origins of the Australopacific firefly fauna, and use of female and larval characters in interpretations of relationships are considered.
The likelihood of dipteran maggots colonizing a corpse due to nocturnal oviposition can be used to challenge the postmortem interval (PMI) estimated assuming diurnal oviposition. Earlier experiments tested nocturnal oviposition behavior by exposing fresh baits once during a single night. In this pilot study, oviposition behavior was studied using beef baits, which, simulating the decay of the body seen in case situations, decomposed inside cages designed to open and close at scheduled intervals during consecutive night or twilight periods. Freshly hatched maggots from diurnally oviposited eggs emerged in control baits on the third day, while a limited number of maggots attributable to nocturnal or twilight oviposition were observed in experimental baits only on the fifth or sixth day, indicating a categorical delay. These results suggest that such delayed and limited nocturnal oviposition is not forensically significant since the larger maggots deriving from diurnal oviposition would be the ones considered when estimating PMI.
Simulium (Nevermannia) maeaiensesp. n. is described on the basis of female, male, pupal and larval specimens collected from Chiang Mai Province, Thailand. This species is assigned to the feuerborni species-group of the subgenus Simulium (Nevermannia), and is distinctive among this species-group in having the female cibarium furnished with numerous dark minute conical processes on the lower part, the female genital fork with a strongly sclerotized horizontal bar on each arm, and six long pupal gill filaments arising nearly at the same level from the common basal stalk and lying in a horizontal plane. Identification keys to seven species of the feuerborni species-group reported from Thailand are provided for females, males, pupae and mature larvae.
In Penang, Malaysia, the Oriental and Afrotropical Megaselia curtineura (Brues) and the Oriental and Japanese Megaselia spiracularis Schmitz are reported from human corpses, these being the first reports of these species in such forensic cases.
A new microhylid, Kalophrynus yongi, Is described from the Cameron Highlands of Peninsular Malaysia. Morphologically, the new species differs from all known congeners by having a very stout forelimb with a humeral spine in males. Acoustically, it resembles K. baluensis and K. heterochirus and sharply differs from K. interlineatus, K. pleurostigma, K. palmatissimus, and K. nubicola.
Studies were carried out on the residual efficacy of Bacillus thuringiensis H-14 (water dispersible granule, VectoBac ABG 6511) as direct application in the control of Aedes larvae in the field. Field Aedes sp populations in the earthen and glass jars were predetermined before initiation of the trial. On confirmation of the presence of Aedes species in the designated area, Sungai Nibong Kecil, Penang Island, Malaysia, Bti was introduced in the 55L earthen and 3L glass jars). Two test designs were carried out. The first design had treated water replenished daily with 6L of seasoned water and the second design is without the replenishment of water but evaporated water was replenished. Bti was effective in the field for at least 35 days with more than 80% reduction in the Aedes larvae in the treated containers. For earthen jars with daily replenishment of water, 100% reduction was recorded for the first 3 days, while more than 80% reduction was recorded up to day 40. At day 60, Bti still provided an efficacy of 54.32 +/- 4.61 (%) of reduction. Whilst for earthen jars without daily replenishment of water, 100% reduction was recorded for the first 5 days, while more than 80% of reduction was recorded up to day 40. For the glass jars studied, similar efficacy was observed. In jars with daily replenishment of water a better larval control was observed. Percentage of reduction from day 50 to 60 for replenishment of water was between 50 to 70% compared to without replenishment of water with less than 40%.
The caste composition and sex ratio in a mature and an incipient colony of Cryptotermes dudleyi Banks (Isoptera: Kalotermitidae) was studied. Biometric descriptors of both immature and sexual castes were developed. Morphometric analysis revealed that there are four larval instars, a pseudergate, and three nymphal instars in the development of C. dudleyi. To differentiate between the fourth larval instars and the pseudergate, pronotal width and tibial length must be taken into account, because the head width overlaps between the two groups. The number of antennal segments increases in parallel with instar development. The mature colony was headed by a pair of physogastric nymphoid neotenics; the colony also contained multiple pairs of nonphysogastric de-alates and wing-torn alates. The majority of eggs and larvae were confined to galleries that connected to locations where nymphoid neotenics were found, whereas in general only pseudergates and nymphs were found together with de-alates and wing-torn alates. In contrast, the incipient colony contained only a pair of primary reproductives. Nymphs formed a major group in both mature and incipient colonies, as did pseudergates. The sex ratio of the mature colony was slightly but significantly biased in favor of females, whereas it was skewed toward males in the incipient colony. The data also suggested that the soldier caste was female skewed.