Allozyme analysis reveals six species within the Anopheles punctulatus complex of mosquitoes in Papua New Guinea

Abstract. Among samples collected from nineteen localities in Papua New Guinea, we have identified six species within the Anopheles punctulatus complex of mosquitoes, by means of cellulose acetate allozyme electrophoresis. An.punctulatus Dönitz sensu stricto was collected from seven villages in the Madang area and from Buksak, Sausi Mission and an area 18 km SW of Tari; An.koliensis Owen from eight villages in the Madang area, from Popondetta and Brown River near Karema; and An.farauti No. 1 from ten coastal areas including Madang, Lorengau, Popondetta, Port Moresby, Rabaul and Wewak. Three newly recognized species, reported here for the first time, are designated as An.farauti No. 4 from Gonoa and Hudini, Madang area; An.farauti No. 5 from Ketarabo near Goroka; and An.farauti No. 6 from Hiwanda near Tari. Three other known members of the complex, An.clowi Rozeboom & Knight, An.farauti No. 2 (Bryan, 1973) and An.farauti No. 3 (Mahon & Meithke, 1982) were not detected in Papua New Guinea. Problems arising with morphological characters for the identification of species in this group are discussed.     

The effect of permethrin-impregnated bednets on a population of Anopheles farauti in coastal Papua New Guinea

The effect of introducing bednets impregnated with 0.4 g/m2 permethrin on local populations of the malaria vector mosquitoes Anopheles farauti Laveran and An. koliensis Owen was monitored in a coastal village of Papua New Guinea. Whole-night landing collections were undertaken for 25 consecutive nights before and 21 nights after the introduction of the nets. Capture-recapture experiments and resting collections were also performed before and after the introduction of the nets. Following the introduction of treated nets, the biting population of An. farauti, the predominant vector, dropped from an average of 689 to 483 per man-night and the oviposition cycle became irregular, although survival rates (determined by time series analysis of the landing catches and log regression of recapture rates) were not significantly affected. The densities of An. farauti resting in and around houses and the human blood index of the engorged females also decreased significantly after introduction of the treated bednets. The population of An. koliensis dropped prior to the introduction of the nets. However, the number of nulliparous females in the landing catches remained more or less constant which implies that, in this species, survival rates were affected by the nets but that recruitment to the population was not.     

Evidence for a ''memorized'' home range in Anopheles farauti females from Papua New Guinea

Evidence is presented that female Anopheles farauti Laveran released in an alien village dispersed more, in their first oviposition cycle after release, than females released in their village of capture. In a subsidiary experiment transporting the mosquitoes did not affect dispersal; wind speed or direction was not sufficient to account for the phenomenon. It is hypothesized that these permanent-pool breeding mosquitoes make appetitive long-range flights to oviposition sites. Mosquitoes blood-fed before midnight had a shorter oviposition cycle than those fed just before dawn. Nulliparous females, and those with well-defined ovariolar dilatations, predominated in the early evening whereas females that had oviposited recently were largely collected in the middle and later parts of the night.     

The Anopheles punctulatus group of mosquitoes in the Solomon Islands and Vanuatu surveyed by allozyme electrophoresis

Abstract. Four species within the Anopheles punctulatus group of mosquitoes (Diptera: Culicidae) were identified by allozyme analysis of samples collected from thirty-three localities in Guadalcanal, Makira, Malaita, Temotu and Western Provinces in the Solomon Islands and six localities on Efate, Espiritu Santo, Maewo and Malekula Islands in Vanuatu. Three of these species are members of the An. farauti complex. A key is given to identify five species of the An. punctulatus group known to occur in the Solomon Islands using their isoenzyme characteristics.
An. farauti No. 1 was widespread in coastal areas of the Solomon Islands and was the only species detected in Vanuatu, including Efate Island (where Faureville is the type locality of An. farauti Laveran sensu stricto). An. farauti No. 2 and An. punctulatus were common in the Solomon Islands in more inland areas. An. farauti No. 7, reported here for the first time, was found as larvae in freshwater at six localities on north Guadalcanal. Three other members of the An. punctulatus group which have been reported previously from the Solomon Islands: An. koliensis, An. renellensis and an electrophoretic variant of An. farauti sensu lato, were not found in our samples.
Previously recognized vectors of malaria and bancroftian filariasis in the Solomon Islands are An. farauti No. 1 (i.e. An. farauti s.s. ), An. koliensis and An. punctulatus s. s. Adult females of An. farauti No. 2 and An. farauti No. 7 were not attracted to human bait in areas where their larvae occurred, indicating that these two species are not anthropophilic and therefore unlikely to transmit human pathogens.     

Differential ecology of Anopheles punctulatus and three members of the Anopheles farauti complex of mosquitoes on Guadalcanal, Solomon Islands, identified by PCR-RFLP analysis

From a series of larval collections made across northern Guadalcanal during the dry season, October–November 1997, four members of the Anopheles punctulatus group of mosquitoes (Diptera: Culicidae) were identified using PCR‐RFLP analysis. Anopheline larvae were found in 54/57 (95%) of the sites sampled, comprising An. farauti Laveran sensu stricto (32 sites), An. farauti species no. 2 (39 sites), An. farauti no. 7 (36 sites) and An. punctulatus Dönitz (10 sites). Anopheles punctulatus occurred only on the coastal plain, where it was associated with the more transient sites. Anopheles farauti sensu lato was more widespread throughout the survey region, with similar proportions of all three sibling species in both transient and permanent sites. Two members of the An. farauti complex, An. farauti s.s. and species no. 2, were found in brackish water. All breeding sites of An. punctulatus were cohabited by An. farauti s.l., sometimes by all three sibling species. Anopheles farauti s.s. was the only species collected on human bait, with a much higher biting rate early in the evening (57 bites/human/hour at 18.30–20.00 hours) than later (0.8 bites/human/hour at 21.00–24.00 hours).     

DNA probes to identify members of the Anopheles farauti complex

DNA probes have been constructed to distinguish between the members of the Anopheles farauti complex of mosquitoes known as species numbers 1, 2 and 3. Partial genomic libraries of the three known species were exposed to labelled total genomic DNA from each species. Colonies showing differential hybridization were selected for further testing. These probes were found which allow identification of the three known species: probe pAf1 (160 bp fragment) hybridizes to DNA from An. farauti nos. 1 and 2; probe pAf2 (95 bp fragment) hybridizes to DNA from An. farauti no. 2 only; and probe pAf3 (1.3 kb fragment) hybridizes strongly to DNA from An. farauti no. 3, less to no. 1 and faintly to no. 2. Increasing the stringency of hybridization reduced the cross-hybridization of probes pAf1 and pAf3. Only radioactively labelled probes were tested. Males and females and individuals from diverse habitats and localities showed the same species/probe hybridization characteristics. This technique allows faster identification of the sibling species than previous methods, and has the added advantage that it allows air-dried and alcohol stored specimens to be identified.     

Impact of untreated bednets on prevalence of Wuchereria bancrofti transmitted by Anopheles farauti in Papua New Guinea

Abstract Despite the growing evidence that insecticide‐treated mosquito nets reduce malaria morbidity and mortality in a variety of epidemiological conditions, their value against lymphatic filariasis infection and disease is yet to be established. The impact of untreated bednets on the prevalence of Wuchereria bancrofti (Cobbold) (Nematoda: Filarioidea) infection and disease was investigated on Bagabag island in Papua New Guinea, where both malaria and filariasis are transmitted by the same vector mosquitoes of the Anopheles punctulatus Dönitz group (Diptera: Culicidae). Community‐wide surveys were conducted recording demographic characteristics including bednet usage. Physical examinations for hydrocoele and lymphoedema were performed and blood samples assessed for filarial and malaria parasites. Mosquitoes were sampled using the all‐night landing catch method and individually dissected to determine W. bancrofti infection and infective rates. Bednet usage among residents was 61% and the mean age of users (25.6 years) was similar to non‐users (22.5 years). Anopheles farauti Laveran was the only species were found to contain filarial larvae: 2.7% infected (all stages), 0.5% infective (L3). The overall W. bancrofti microfilaraemia and antigenaemia rates were 28.5% and 53.1%, respectively. Bednet users had lower prevalence of W. bancrofti microfilaraemia, antigenaemia and hydrocoele rates than non‐users. In comparison, untreated bednets had no effect on the prevalence and intensity of Plasmodium falciparum and P. vivax infections. The impact of bednet usage on rates of microfilaraemia and antigenaemia remained significant even when confounding factors such as age, location and sex were taken into account, suggesting that untreated bednets protect against W. bancrofti infection.     

Mass treatment with ivermectin for filariasis control in Papua New Guinea: impact on mosquito survival

Field studies were carried out to determine the impact of mass human treatment with ivermectin on the survival of anthropophagic mosquitoes of the Anopheles punctulatus complex (Diptera: Culicidae), the vectors of lymphatic filariasis and malaria in Papua New Guinea. In a village where mass treatment had been given, using 400 microg/kg ivermectin plus 6 mg/kg diethylcarbamazine citrate (DEC), we performed pre- and post-treatment collections of freshly blood-engorged mosquitoes from the same nine bedrooms. All blood-fed mosquitoes collected less than 4 days after mass treatment died within 9 days, whereas 67% of those collected before treatment survived for >9 days. Comparison (using the log-rank test) of the survival curves for mosquitoes collected (i) before treatment, (ii)<4 days after treatment, and (iii) 28 days after treatment, showed the survival rate of group (ii) to be significantly lower than the other two (chi2=176, df=2, P<0.0001). Pre- and post-treatment all-night landing catches showed no reduction in human biting rates in the experimental village. In another village, where people were mass treated with ivermectin (400 microg/kg) only, the survival rates of freshly blood-engorged An. punctulatus collected from bedroom resting-sites less than 1 day after treatment, were compared to similar collections carried out at the same time in a nearby village where people were not treated with ivermectin. The 48-h survival rate for the ivermectin-treated village was 31% compared to 94% for the other; this difference was highly significant (chi2=32.42, df=1, P<0.0001). Mosquitoes fed 2 months post-treatment with DEC or collected 38 days post-treatment with ivermectin had normal survival rates. We conclude that the duration of the systemic lethal effect of ivermectin on mosquitoes is insufficient to be of epidemiological significance in filariasis control programmes that are based on biannual and annual single-dose treatments, but might reduce vectorial capacity sufficiently to block epidemics of dengue or even malaria.     

Contributions to the Cladocera fauna from Papua New Guinea

Twenty-eight taxa of the Cladocera are identified in collections from Papua New Guinea, 17 being new records for New Guinea, bringing the total number of Cladocera taxa reported for this region to 39. Most of the taxa are circumtropical. One species (Sarsilatona papuana) is endemic to Papua New Guinea and northern Australia. The species list includes two species that are normally listed as Holarctic:Alonella nana andAlona rustica. Widespread genera such asDaphnia, Pleuroxus, Disparalona, Acroperus were strikingly absent from the Papua New Guinean material.     

Responses of mosquitoes of the Anopheles farauti complex to 1-octen-3-ol and light in combination with carbon dioxide in northern Queensland, Australia

Abstract. In northern Queensland, Australia, three experiments were conducted to determine the response of mosquitoes of the Anopheles farauti complex to CDC traps baited with four attractant combinations: octenol + C0₂ and light; octenol and light; CO, and light; or C0₂ and octenol without light. A CDC-modified updraft light-trap was also trialled, but did not significantly enhance collections of An.farauti sensu lato. The combination of light, octenol and C0₂ caught significantly more An.farauti s.l. (both An.farauti No. 1 and No. 2 sibling species) when compared to C0₂ and light alone. Only small numbers of the An.farauti complex were captured when CDC traps were baited with octenol alone, i.e. no light or C0₂.     

Use of rDNA-PCR to investigate the ecological distribution of Anopheles bwambae in relation to other members of the An.gambiae complex of mosquitoes in Bwamba County, Uganda

Abstract Environmental relationships were investigated among three species of the Anopheles gambiae complex of mosquitoes associated with the geothermal springs located in Bwamba County, Uganda. The degree of ecological isolation between An.gambiae and An. bwambae, a sibling species known only from the geothermal springs environment, was assessed on the basis of adult distribution and abundance as well as differences in larval habitats. Field data were gathered during June 1995 without knowing which of the species were being collected. Specimens identified subsequently by rDNA-PCR were used to interpret the ecological data. Ten of twenty aquatic sites sampled were found positive for immature stages of the An.gambiae complex. Larvae of An.bwambae were associated with ‘springwater’ habitats having much higher conductivity, much greater concentrations of dissolved solids and slightly higher temperature and pH than ‘normal’ fresh water sites inhabited by larvae of An.gambiae. Larval habitats of both species were unshaded: An.bwambae occurred among dense sedge (Cyperus laevigatus) whereas those of An.gambiae were almost devoid of vegetation. One mixed sample showed that larvae of both species occur together in peripheral aquatic sites with intermediate physical and ecological characteristics. In water preference tests, free-flying females were reluctant to lay eggs on bowls of water in cages; gravid females (with one wing amputated) placed on the surface of water in a cup laid eggs on seasoned rainwater (12/51 An.bwambae; 2/3 An.gambiae) as well as spring-water (39/51 An.bwambae; 1/3 An.gambiae). All three An.gambiae oviposited on the first water option, whereas 86% of An. bwambae witheld oviposition until being moved to the other type of water after 5–6 h, and 82% (36/44) of these laid eggs on geothermal water in preference to rainwater. Larval and adult collections showed that An.gambiae occurs sympatrically with An.bwambae throughout its range in the humid foothill environment of the geothermal springs, whereas the distribution of An.arabiensis overlaps only slightly with An.bwambae towards the savanna environment north of the springs.     

Caprellids (Crustacea: Amphipoda) from Papua New Guinea,with the description of a new species

This is the first study of caprellid amphipods from the coast of Papua New Guinea. Several collections from Madang Lagoon (north) and Bootless Bay (south) have been studied. Seven species in seven genera are recorded, of which Pseudoproto papua sp. nov. is described as new to science. The genus Pseudoproto Mayer, 1903 has consisted, so far, of only one species, Pseudoproto fallax Mayer, 1903. Although only a single male has been found of Pseudoproto papua sp. nov., differences in antennae, mouthparts, gnathopod 2 and pereopods 3 and 4 have revealed that it represents a new species of Pseudoproto. Lateral view figures of all species, together with a key to species level for the Caprellidea from Papua New Guinea are also included. Communicated by H.-D. Franke     

Impact of permethrin-impregnated mosquito nets compared with DDT house-spraying against malaria transmission by Anopheles farauti and An.punctulatus in the Solomon Islands

Abstract. In villages of northern Guadalcanal in the Solomon Islands, where the predominant malaria vector is An.farauti No. 1 and An. puctulatus is also involved, malaria transmission rates were compared for three zones: (1) non-intervention: 438 people in seventeen villages; (2) residual DDT house-spraying two cycles per year: 644 people in thirty villages; (3) bednets impregnated with permethrin 0.5 g/m² twice per year, used by 580 people in sixteen villages. Regular DDT spraying in zones 1 and 3 had been withdrawn 18 months previously. Malariological blood smear surveys of children aged 1-9 years in August 1986 to January 1987 showed a mean-baseline malaria parasite rate of 38% (32/84). By February 19 88 , 18 months after introduction of impregnated bednets, the Plasmodium falciparum infection rate in children was lowest in the zone using impregnated bednets (21% of 29), intermediate in the untreated zone (29% of 34) and highest in the DDT zone (46% of 53), but these differences were not statistically significant. P.vivax infection rates were 9–14%. Using ELISA tests for malaria circumsporozoite antigen in the vectors, overall positivity rates were 0.7% of 49 ,902 An.farauti and 2.54% of 118 An.punctulatus, comprising 228 P.falciparum and 124 P. vivax infections. In the study zones, vector positivity rates were 0.93% of 31 ,615 An.farauti in the untreated zone; 0.32% of 16, 883 An.farauti in the DDT zone; 0.07% of 1404 An.farauti and 2.54% of 118 An.puctulatus in the impregnated bednet zone. There was no significant correlation between malaria parasite rates in the vectors and the children. Entomological inoculation rates were consistently highest in the untreated zone (1.6–2.8 infective bites/night), intermediate in the DDT zone (0.8– 1.1/night) and significantly lowest in the bednet zone (0.03-0.23/night). Geometric mean densities of P.falciparum sporozoites were also significantly higher in the DDT zone (50% > 10,000 sporozoites/mosquito compared with 20% in untreated zone). The highest individual infection density was an estimated 52,080 sporozoites of P.falciparum in a specimen of An.punctulatus from the bednet zone. P.vivax sporozoite densities were not significantly different between zones, and both species of vector had similar mean sporozoite loads for both species of malaria. It is concluded that permethrin-impregnated mosquito nets exerted significantly more impact on vector infectivity and the inoculation rate than resulted from DDT spraying. Even so, the inoculation rate for people in the bednet zone remained at one infective bite every 4–32 days, an insufficient reduction to control malaria without additional countermeasures. Ineffectiveness of house-spraying and the limited impact of impregnated bednets are attributed to exophily and other behavioural aspects of An. farauti.     

Lactate dehydrogenase allozyme differentiation of species in the Anopheles culicifacies complex

Abstract Genetically controlled enzyme variation exists within and between four sibling species of the Anopheles culicifacies complex of malaria vectors in India. A study on electrophoretic variation of nine enzymes in An.culicifacies sibling species revealed that the lactate dehydrogenase ( Ldh ) locus has Fast (F) and Slow (S) allozymes distinguishing species A+D from species B+C with a probability of c . 95%.     

Parabrosmolus novaeguineae,a new genus and species of the subfamily Brosmophycinae from Papua New Guinea (Bythitidae,Ophidiiformes)

Parabrosmolus novaeguineae, a new genus and species of the subfamily Brosmophycinae (family Bythitidae) is described, based on a single specimen from Papua New Guinea. The genus is unique in the tribe Brosmophycini in having six branchiostegal rays and ten precaudal vertebrae, and is also similarly distinguished from two brosmophycine genera,Melodichthys andBeaglichthys, tribal allocations of the two latter being uncertain.Parabrosmolus also differs from all other genera in the subfamily by the following combination of characters: head scaly, anal fin origin slightly before midpoint of body, eye diameter shorter than snout length, three developed rakers on first gill arch and 16 (14+2) caudal fin rays.     

Introduction: The Politics of Order in Contemporary Papua New Guinea

ABSTRACT

This collection of articles seeks to demonstrate that the concept of order – the intensive and extensive coordination of human action across space and time – is useful for answering some of the most pressing theoretical and practical questions in contemporary Papua New Guinea (PNG) today. Building on existing work in this field [Benda-Beckmann, K., and F. Pirie. 2007. “Introduction.” In Order and Disorder: Anthropological Perspectives, 1–15. New York: Berghahn Books] in this special issue we ask: How do people create enduring, stable, and routinised life in contemporary Melanesia today? We position our work as the next step in a growing movement to study contemporary institutions in PNG as order-making projects, rather than attempting to divide them into legitimate projects like ‘government’ and false or ineffective ones like ‘cargo cults’.     

A multivariate approach to fingerprint variation in Papua New Guinea: Implications for prehistory

Fingerprint data from three Markham Valley populations of Papua New Guinea are presented. Initial comparisons with data from elsewhere in New Guinea by conventional bivariate methods suggest hypotheses regarding prehistory, but these methods are inconclusive. Because of this shortcoming, the application of discriminant analysis to dermatoglyphic data is justified and cautiously demonstrated. Discriminant analysis is a valid approach to the parsimonious study of fingerprint relationships among human populations. Significant discriminating variables are then used with the limited published data to display historical relationships. These marker traits include the separate frequencies of thumb, middle fingers, and little finger patterning, and the complexity of the thenar eminence. With regard to prehistory, it is concluded that fingerprint data support the hypothesis of separate origins and migrations for Papuan- and Melanesian-speaking peoples. Furthermore, it is suggested that these data support the linguistic hypothesis of a second Papuan migration of Trans New Guinea Phylum speakers, up the Markham Valley into the New Guinea Highlands. Finally, gene flow is indicated from Melanesian speakers of the north coast into the interior through the Sepik and Ramu River valleys, affecting both the Trans New Guinea Phylum and other unrelated Papuan groups. Moreover, there are numerous suggestions of recent reciprocal genetic exchange between neighboring Melanesians and Papuans, without obliterating the older, separate origins of these peoples. These results suggest that fingerprints have greater phylogenetic stability than other biological parameters used in the past.     

Revision of the termite family Rhinotermitidae (Isoptera) in New Guinea

Recently, we completed a revision of the Termitidae from New Guinea and neighboring islands, recording a total of 45 species. Here, we revise a second family, the Rhinotermitidae, to progress towards a full picture of the termite diversity in New Guinea. Altogether, 6 genera and 15 species are recorded, among which two species, Coptotermes gambrinus and Parrhinotermes barbatus, are new to science. The genus Heterotermes is reported from New Guinea for the first time, with two species restricted to the southern part of the island. We also provide the first New Guinea records for six species of the genera Coptotermes and Schedorhinotermes. We briefly describe soldiers and imagoes of each species and provide a key based on soldier characters. Finally, we discuss the taxonomic and biogeographical implication of our results. A replacement name, Schedolimulus minutides Bourguignon, is proposed for the termitophilous staphylinid Schedolimulus minutus Bourguignon, to solve a question of secondary homonymy.     

DNA probes for species identification of mosquitoes in the Anopheles gambiae complex

Abstract. Identification of species within the Anopheles gambiae Giles species complex is essential for the correct evaluation of malaria vector ecology studies and control programmes. The development of DNA probes to distinguish species of the An.gambiae complex is described. Genomic libraries were prepared for four members of the An.gambiae complex. These were screened using radiolabeled DNA from different species of An. gambiae sensu lato and a number of clones selected on the basis of their species specificity. These clones could be divided into two groups, each containing homologous sequences. Sequences homologous to group 1 inserts are highly reiterated in the genomes of Anopheles arabiensis Patton and Anopheles merus Dönitz, present in low copy number in Anopheles melas Theobald, but were not detected in Anopheles gambiae sensu stricto. Studies on the organization of this sequence in the genome of An.arabiensis show that homologous sequences are male specific and interspersed within the chromatin. Sequences homologous to group 2 inserts are highly repeated in the genomes of An.merus and An.melas, but present in low copy number in An.gambiae s.s. and An.arabiensis. Group 2 homologous sequences are not sex-specific in the species tested and appear to be tandemly repeated. When used as hybridization probes, these sequences provide a sensitive means for the identification of species within the Anopheles gambiae complex.