bluuebunny/crossref_metadata_2025_split huggingface dataset:
The status of the foreign grain beetle, Ahasverus advena (Waltl) (Col., Silvanidae), as a pest of stored products
Authors: Woodroffe G. E. 
Published: July 2009

The ability of the foreign grain beetle, Ahasverus advena (Waltl), a reputed mould feeder, to breed on various foods under conditions not conducive to mould growth was investigated in a series of culturing experiments. At 25°C., on a diet of rolled oats and dried yeast, the lowest relative humidity at which successful breeding occurred was 65 per cent., although a few adults were produced at 60 per cent. R.H. Wheat germ proved a satisfactory food under these conditions and the addition of yeast or germ to cereal products enabled the species to breed in the absence of visible mould growth, which it failed to do on. the cereal products alone. Although thriving larval cultures developed with crushed, dead grain weevils (Sitophilus granarius (L.)) as food, they invariably died out without producing pupae. On oilseeds at 70 per cent. R.H., moderate breeding occurred on groundnuts, which remained free from visible mould, but little or none on copra, cocoa or palm kernels in the absence of mould.It is concluded that most stored foodstuffs are deficient in some factor, present in adequate quantity in dried yeast or wheat germ, that A. advena requires for successful breeding and that, in the field, this requirement frequently limits the species to mouldy products, although direct damage to groundnuts at 30°C. and 70 per cent. R.H. is possible in the apparent absence of mould.
Age determination for female tsetse flies and the age compositions of samples ofGlossina pallidipesAust.,G. palpalis fuscipesNewst. andG. brevipalpisNewst.
Authors: Saunders D. S. 
Published: July 2009

The age compositions of samples of females ofGlossina pallidipesAust.,G. palpalis fuscipesNewst. andG. brevipalpisNewst., are analysed by means of a method of age determination based upon the changes occurring in the reproductive system during successive gonotrophic cycles. This method of age determination is described in detail.Females were sampled by three main methods: in traps, by catching on a bait-animal, and on a fly-round. Some flies were also found as resting flies in the undergrowth.Trap-caught samples ofG. pallidipeswere older (i.e.), contained a larger proportion of old flies (and a smaller proportion of young flies) than the hand-caught samples. The bait-caught samples were intermediate in age structure. Correlated with the increasing mean age in the hand-caught—bait-caught—trap-caught series was an increase in the proportion of females carrying third-instar larvae and a decrease in the proportion of those carrying eggs. Results with samples ofG. palpalis fuscipesandG. brevipalpiswere not so well defined.The results of dissecting teneral and non-teneral nullipars ofG. pallidipesandG. palpalis fuscipesindicate that females of the latter are inseminated some time before they take their first blood-meal, but teneral females ofG. pallidipesare inseminated when they come to the host to feed or after they have fed.The relation of the ovarian method of age determination to Jackson's (1946) wing-fray categories in females ofG. pallidipes, and the probable epidemiological importance of the samples, are also discussed.
Observations on Toxorhynchites brevipalpis conradti Grünb. (Diptera, Culicidae) in Uganda
Authors: Corbet Philip S. 
Published: July 2009

Observations made in Uganda on eight individuals of the mosquito Toxorhynchites brevipalpis conradti Grünb. reared in captivity from egg to adult are recorded. Larvae of this species are predatory and coexist in tree holes with those of mosquitos of medical importance.The identification of larvae and pupae is discussed, and information provided on the following subjects: the amount of food (living larvae of Aedcs acgypti (L.)) needed for larvae to complete development; the feeding and killing behaviour of fourth-instar larvae; duration of the pupal stage; and the rate of autogenous ovarian development in the unfed female adult.The compulsive killing behaviour shown by a fourth-instar larva about two days before it pupates could be expected to cause the death of all the other mosquito larvae in a tree hole of average size. This species is unusual among mosquitos in that pupae of females developed more rapidly than those of males.
A method of assessing the physical condition of insect-damaged grain and its application to a faunistic survey
Authors: Coombs C. W. 
Published: July 2009

A method of assessing the physical condition of grain residues is described. It consists of utilising data obtained by taking the weight and volume of samples before and after sieving over a 1/10-inch mesh.The application of this method to a survey of the insect population of wheat residues beneath the floor of a small granary in southern England is described. Information from the weight and volume data obtained enabled the samples to be classified in a manner agreeing with visual estimates. It had the advantage of objectivity.Three vertical series of samples were taken and analysed, and the insects present counted and identified. The size, composition and distribution of the insect population is briefly discussed in relation to the condition of the residues and their depth below the surface. The fauna consisted of grain pests (Sitophilus granarius (L.), Oryzaephilus surinamensis (L.), Ptinus tectus Boield., P. fur (L.) and Hofmannophila pseudospretella (Stnt.)) and incidental species (fungus feeders and ground-dwellers) and the two groups differed in their distribution and in their apparent response to the physical conditions.
Simultaneous control of three species of Glossina by the selective application of insecticide
Authors: Maclennan K. J. R. , Aitchison P. J. 
Published: July 2009

An account is given of the simultaneous control of three species of tsetse fly by the selective application of insecticide to vegetation within an area of 16 sq. miles along a seasonal watercourse in Northern Nigeria constituting a permanent habitat of Glossina palpalis (R.-D.) and G. tachinoides Westw. and a hot-season concentration area of G. morsitans Westw. subsp. submorsitans Newst. The ecological zones concerned centred on small lakes fringed, in succession outwards, by open swamp, swamp woodland, swamp forest, riparian forest and riparian woodland, the whole being bounded by savannah woodland populated by G. morsitans in the wet season. All except the forest elements were subject to seasonal fires.Against G. morsitans, insecticide was applied to the principal resting sites of flies in their hot-season concentration habitats, namely, the basal 5 ft. of shaded tree trunks over 9 in. in diameter, or 5 in. where stands were dense, in, chiefly, riparian woodland and forest. Against the other species it was applied to a height of 2½ ft. on stems, trunks and exposed roots in riparian forest and the margins of swamp forest, which were favoured as pupation sites and in which it was therefore believed that adults might rest.A wettable-powder suspension containing 3¾ per cent. DDT was applied by pneumatic knapsack sprayer in quantities short of run-off. Temporary reduction of the strength to 2½ per cent, had no detectable effect on control.Regular fly patrols showed an initial reduction in apparent density of G. morsitans by four-fifths, but spot checks detected a residual population that persisted up to two months in small areas. These were resprayed so as to include trunks of 5 in. diameter and branches over 3 in. in diameter at heights of 6–12 ft. The apparent density of the other species declined after treatment by over nine-tenths, in both treated and untreated zones, but following catches of a few teneral adults, indicating persistent or recurrent populations in limited areas, these were resprayed using an emulsion containing 3¾ per cent, dieldrin.Treatment began in January 1961 and to date (April 1963) no fly has been detected since April 1961, despite repeated re-surveys. The approximate cost of labour, equipment and insecticide was £3,000; an attempt at reclamation in 1926–29 by sheer-felling over seven sq. miles, which achieved only temporary success, had cost £3,000, with recurrent annual re-slashing costs of £250, equivalent to £12,000 and £1,500, respectively, at present-day costs for labour.
Seasonal patterns of age-composition of sylvan mosquito populations in Uganda (Diptera, Culicidae)
Authors: Corbet Philip S. 
Published: July 2009

Fifty-two standardised weekly collections of female mosquitos were made by human catchers at ground-level in lake-side forest near Entebbe, Uganda. The numbers of nullipars and pars in each sample were recorded, in order to determine whether the capacity of these mosquito populations to transmit virus varied seasonally. Methods are described for handling large catches for the purpose of identifying and age-grading. The total sample comprised 31,978 mosquitos belonging to 37 or more species. Results for 15 species are presented in detail.The nulliparous rate (i.e., the number of nullipars as a percentage of total females) differs markedly between species, but relatively little within species. Certain species of Mansonia (Coquillettidia), mainly swamp breeders, have the highest nulliparous rate, and species of Aedes and Eretmapodites, which breed in small containers, have the lowest. In some species, biting females show a lower nulliparous rate than those caught resting.Culex annulioris Theo. and species of Mansonia, which are swamp breeders, have a main peak of abundance between May and July, during the main rains and when lake-level is highest. Species of Aedes (Stegomyia), which are tree-hole or small-container breeders, show small, irregular, short-term fluctuations in numbers.The number of pars, an epidemiologically important parameter, is absolutely highest at or soon after the time of greatest abundance. For certain bird-biting mosquitos, namely, Culex annulioris and species of Mansonia (Coquillettidia), most pars are found during the main rains, when susceptible hosts are also most numerous. Implications of these findings on virus-isolation programmes are briefly discussed.
The spread of apterae of Myzus persicae (Sulz.) and of yellows viruses within a sugar-beet crop
Authors: Ribbands C. R. 
Published: July 2009

Populations of the wingless form of Myzus persicae (Sulz.), infected with severe yellows (SBYV), mild yellows (SBMYV), and both viruses, were introduced to single sugar-beet plants which were growing in a normal crop.The aphids and their progeny walked readily from plant to plant, both along and across the rows, during the following eight weeks. Although they were heavily attacked by ladybirds, their mobility saved the population from total destruction. They carried and transmitted the viruses; within a month patches of sugar beet more than 11 feet in diameter had become infected, and within two months the diameter had extended to about 20 feet.SBMYV spread to more than twice as many plants as SBYV. When introduced alone, either virus spread to twice as many plants as when the two viruses were introduced together. The rate of increase of the infection fell off during the season; it was estimated as eight- to sixteen-fold per month in June—July, about three-fold in August, and 1·5- to 1·9-fold in September. Natural infections-appear to behave similarly.Apterae of M. persicae are considered to be predominantly responsible for yellows virus transmission within the crop, and their mobility, in contrast to the immobility of those of A. fabae Scop., is considered to be the principal reason why M. persicae is a much more important vector than A. fabae.The extent of spread of virus by apterae shown to occur in the root crop must inevitably be much greater in the seed crop, in which aphid populations are much higher. This consideration serves to explain why existing control measures in the seed crop do not protect the root crop from infection. The risk from the seed crop, which is the reservoir of the disease, would be countered if seed crops were grown only in alternate years.
Laboratory studies on dispersion behaviour of adult beetles in grain. II.—The saw-toothed grain beetle, Oryzaephilus surinamensis (L.) (Coleoptera, Silvanidae)
Authors: Surtees Gordon 
Published: July 2009

Dispersion behaviour in adults of the saw-toothed grain beetle, Oryzaephilus surinamensis (L.), was studied under controlled laboratory conditions. The effect of density, temperature and moisture content on surface dispersion was studied using groups of insects in jars of 500 g. grain and vertical dispersion by using groups of insects in thin vertical plates of wheat held between two sheets of glass. The ethological basis of group behaviour was investigated by using isolated individuals.Over the range of conditions used, 1–10 per cent, of the individuals comprising the groups studied appeared on the surface of the grain. In grain at 14 per cent, moisture content, at 25°C., 3·4 per cent, of the group appeared on the surface. A greater proportion was found on the surface of grain at 9 per cent, moisture content than at higher moisture contents at all temperatures tested (15–35°C.). At all moisture contents, surface numbers were relatively high at 15°C.In grain at 14 per cent, moisture content and 25°C., individuals moved vertically and laterally at random but were more active in the evening than in the morning. In grain at 9 per cent, moisture, there was marked irritability, and at 15°C. and 14 per cent, moisture, there was continual but slow movement without any detectable diurnal pattern of activity. Activity was reduced at 30°C., and at 25°C. it was reduced in grain of 17 per cent, moisture content.The significance of these results is discussed in relation to the detection of populations, group formation and the initiation of foci of heating in patches of damp grain.
Studies on mosquitos (Diptera, Culicidae) biting birds, using twenty-four-hour catches, in the Entebbe area, Uganda
Authors: Williams M. C. 
Published: July 2009

Series of 24-hour catches at different levels were made at Zika and Lunyo in the Entebbe area, Uganda, using fowls (White Leghorn cocks) as bait, and some comparative catches were made with man as bait.Thirty-seven different mosquito species (including five species groups) were taken on the avian bait.The vertical distributions and biting cycles of each of nine species (including one species group), Anopheles implexus (Theo.), Mansonia (Coquillettidia) aurites (Theo.) gp., M. (C.) fuscopennata (Theo.), M. (Mansonioides) africana (Theo.), Hodgesia cyptopus Theo., Aedes africanus (Theo.), A. apicoargenteus (Theo.), A. ingrami Edw. and Culex annulioris Theo. were similar on human and avian bait.At Lunyo both A. africanus and C. annulioris had a marked diurnal peak, which had not been described previously.Comparison of the numbers coming to avian and human bait indicate that species of Culex, H. cyptopus and most of the species of Mansonia (Coquillettidia) have a preference for birds.
Ecology and host-relationships of ticks (Ixodoidea) infesting domestic animals in Kassala Province, Sudan, with special reference to Amblyomma lepidum Dönitz.
Authors: Karrar Gaafar , Kaiser Makram N. , Hoogstraal Harry 
Published: July 2009

Amblyomma lepidum Dön., previously incriminated as a vector of heartwater (caused by Rickettsia ruminantium) among sheep and goats, and possibly camels, in southern Kassala Province, Sudan, is apparently the only Amblyomma species in this area. Systematic collections of all ticks infesting domestic animals were carried out in November 1959, just after the rains, in five ecologically differing areas in the region most severely infected with heartwater. Though rare in desert scrub (north of 16°N. latitude) and only moderately numerous in semidesert grassland (Butana area), incidence of A. lepidum is high in wooded savannah (River Atbara) and in the cultivated Gash Delta, and highest (15·5 per host) in the Acacia seyal savannah of the River Gash. Chief hosts of adults are cattle. Sheep are secondary hosts, and camels, donkeys, and goats are less heavily infested. Two males were taken feeding on humans. Mating (breeding) activity is only slight following the rains (November). Few larvae and nymphs were found during this period; those present were mainly on sheep and goats, with a few on cattle, and these were usually feeding on the hoofs of their hosts.Rhipicephalus s. sanguineus (Latr.), the most numerous and widely distributed tick here, infests chiefly sheep and goats, is common on cattle, and also occurs on camels and donkeys. Mating activity of this species is high in November. Hyalomma dromedarii Koch is equally widely distributed and follows R. s. sanguineus in numbers, but is most frequent on camels, common on cattle, and rare on donkeys and sheep; goats were uninfested. Mating is moderately active at this season. The incidence of H. impeltatum Schulze & Schlottke, which occurs in each zone, equalled that of A. lepidum. Cattle are the chief hosts and camels are secondary hosts; donkeys, sheep, and goats are less frequently infested. Mating activity is moderate in November.Other more or less common tick species on these domestic animals are Boophilus decoloratus (Koch), R. e. evertsi Neum., R. simus Koch, H. anatolicum excavatum Koch, H. truncatum Koch and H. marginatum rufipes Koch, evidence for the status of which as a subspecies of H. marginatum Koch is to be presented in a subsequent paper. Several other rare species are also recorded.
An investigation into the behaviour of Anopheles parensis Gillies at Malindi on the Kenya coast
Authors: Gillies M. T. , Furlong M. 
Published: July 2009

In investigations made in January to November 1962, Anopheles parensis Gillies was found biting man in large numbers in a zone near Malindi, Kenya, in which house-spraying with DDT had been carried out between March 1961 and October 1962. Densities were greatest just outside villages, less so on the verandah of a house and least indoors. In one open type of unsprayed house, however, moderately large numbers were caught. The monthly average catch per night by two men was greatest (over 200) outdoors in July and August.Biting activity reached two peaks during the course of the night, catches in all situations being greatest during the two hours following sunset and the three hours preceding sunrise. The evening peak was highest in the outdoor catches, and the late-night peak in the indoor collections. A distinct influence of moonlight on the catches was observed, the early evening peak under certain conditions being greater during the moon's first quarter and the late-night peak during its last quarter.Numbers of examples were caught biting cattle, but owing to the absence of large herds of stock it is believed that most feeding took place on man. The proportion of nulliparous females was 64 per cent, in the sprayed zone and 50 per cent, in an unsprayed village, and in the latter the nulliparous rate in females resembling A. funestus Giles (the majority of which would have been that species) was 24 per cent. No specimen of A. parensis infected with sporozoites was found in the sprayed zone. In the unsprayed village, no infected glands were found in a small series dissected. Thus no evidence was obtained that A. parensis was acting as an exophilous vector of malaria in the sprayed zone. Moreover, in view of the high nulliparous rate observed in the unsprayed area, this species is considered unlikely to be of any importance under normal conditions.
The biting habits of Aedes (Skusea) pembaensis Theo. and some other mosquitos of Faza, Pate Island, East Africa
Authors: van Someren E. C. C. , Furlong M. 
Published: July 2009

Descriptions are given of 24-hour biting catches, made in and around Faza, a village on Pate Island, off the north-east coast of Kenya, East Africa.Aedes pembaensis Theo. was the predominant mosquito in these catches but fair numbers of Aedes mombasaensis Mattingly were also taken; the biting cycles of these two are discussed. Six other species were taken in small numbers.For Ae. pembaensis, biting cycles calculated on catches grouped for site, moon phases, neap tides and spring tides show that both moon and tide and light intensity influence the biting behaviour. Different but recurring patterns occur with various combinations of these factors.For Ae. mombasaensis, the cycles have a very constant biphasic pattern. Catches grouped for moon phases, tides and catch sites, as for Ae. pembaensis, show that more biting females are taken at neap tides than at spring tides. Two patterns of behaviour occur, one associated with spring tides and the other with neap tides. An even level of biting activity occurs during the night with intense and prolonged moonlight; otherwise moon-phase cycles have little effect on biting behaviour.It is felt that 24-hour biting catches can give useful information on behaviour patterns but it is desirable to have a long series of catches to analyse. For the purpose of calculating biting cycles, the results of catches showing similar modifications in behaviour should be treated separately.
Resistance to BHC in the cattle tick Boophillus microplus (Can.) in India
Authors: Chaudhuri R. P. , Naithani R. C. 
Published: July 2009

Cattle kept at the Latoli kraal of the Indian Veterinary Research Institute at Mukteswar in the Kumaon foothills of the Himalayas were heavily infested with the tick Boophilus microplus (Can.). In order to reduce the infestation, the animals were treated with BHC dusts every season for a number of years. In 1960, it was noticed that the treatment was not as effective as in the previous years. A series of concentration/response tests was therefore carried out in 1961–62 to see whether or not the tick had developed any resistance to BHC. Ticks collected from cattle in a village about five miles distant, where no acaricide had ever been applied, were used as the standard for comparison. BHC as a wettable powder was used to provide six different concentrations of γ BHC for engorged females and unfed larvae, respectively. Treatment was by appropriate dipping techniques. Analysis of the results showed that the population of B. microplus infesting cattle at the Latoli kraal had developed resistance to BHC. The LC50's of γ BHC for engorged females and unfed larvae, respectively, of the Latoli population were 0.5164 and 0.0182 per cent., and of the village population 0.0834 and 0.00069 per cent. This seems to be the first record of any species of tick developing resistance to an acaricide in India.It was found that the mean number of eggs laid per tick in the control batches was higher in the village population than in the Latoli population and that the difference was highly significant.
Seasonal changes in populations of phlebotomine sandflies (Dipt., Psychodidae) in Kenya
Authors: Minter D. M. 
Published: July 2009

An account is given of seasonal changes in the incidence and relative abundance of a number of Phlebotomine sandflies which rest in termite hills in two widely separated areas of Kenya.The annual pattern of rainfall distribution is shown to be of greater importance than the total precipitation in influencing the gross distribution and local abundance of many sandflies.Kenya sandflies fall readily into ‘ perennial ’ and ‘ rainy-season ’ groups: the former have a wide distribution and appear to breed throughout the year. The distribution of the ‘ rainy-season ’ sandflies is relatively restricted, since these species are found almost exclusively in areas with a bimodal pattern of annual rainfall; it is suggested that they may survive the intervening dry periods in larval diapause. The length rather than the severity of the dry seasons is thought to be the limiting factor in the distribution of ‘ rainy-season ’ species.Examples are given of the seasonal changes in structure of populations made up of several species sharing, in the adult form, the same termite-hill habitat.