bluuebunny/crossref_metadata_2025_split huggingface dataset:
The population dynamics of the stinging nettle aphid, Microlophium carnosum (Bukt.)
Authors: PERRIN R. M. 
Published: March 2008

Abstract

Populations of Microlophium carnosum on patches of perennial stinging nettle, Urtica dioica increased rapidly during April and May to reach their peaks in June. The decline in numbers was equally rapid and very small populations persisted into autumn; parthenogenetic over‐wintering was recorded.
Suboptimal ambient temperature and mortality due to natural enemies contributed mainly to the post‐peak development of aphid populations.
The combined effects of intraspecific competition and a deterioration in the food quality of the host plant appeared to be the major factors determining the temporal pattern of aphid abundance.
Variation in the size of populations between the three sampled sites was correlated with differences in the food quality of nettles as indicated by aphid mean relative growth rate.
Each nettle patch has a particular ‘carrying capacity’ for aphids, within which a biennial fluctuation between relatively large and small aphid populations appeared to be emerging at most of the sites investigated. A natural or aphid‐induced cycle in host plant quality, or alternatively, the persistent effects of intraspecific competition over several generations, may explain this fluctuation.
The hosts of Nemeritis canescens a problem in the host specificity of insect parasitoids
Authors: SALT GEORGE 
Published: March 2008

Abstract

Published records of the hosts of N.canescens have been collected and critically examined.
It is accepted that canescens has developed on twenty‐three species; on one of them perhaps accidentally, on two with some doubt.
Twelve species were parasitized in nature; nine species in the laboratory. Two species served as hosts when artificially infected.
The natural hosts belong in the Pyralidae, Tinaeidae and Yponomeutidae; the laboratory hosts in the Pyralidae, Oecophoridae and Gelechiidae. One individual was reared from a Tortricid, perhaps accidentally.
The host specificity of N.canescens is not easily explained on either a systematic or an ecological basis. It offers interesting problems for research.
The status of the swallowtail butterfly in Britain
Authors: DEMPSTER J. P. , KING M. L. , LAKHANI K. H. 
Published: March 2008

Abstract

Since the early 1950s, when the British swallowtail butterfly (Papilio machaon britannicus) became extinct at Wicken Fen, this subspecies has been confined to marshes around the Norfolk Broads. Here too, however, its abundance appears to be declining.
The ecology of the butterfly has been studied in Norfolk and at Wicken (by small‐scale introductions) and the main factors determining its abundance are described.
A morphometric study of museum specimens has shown that populations of the butterfly in Norfolk and at Wicken differed in a number of size and shape characters. These differences were most marked between 1890 and 1920, but subsequently were almost lost.
Studies of the status and performance of the butterfly's food plant, Peucedanum palustre have shown that it is smaller, produces less seed, and is shorter‐lived at Wicken than in Norfolk.
In the light of these findings, the possibility of successfully re‐establishing the butterfly at Wicken, and the possible causes of the decline of the species in Norfolk are discussed.
The biology of Microctonus caudatus (Thomson), a braconid parasite of the ground beetle Harpalus rufipes (Degeer)
Authors: LUFF M. L. 
Published: March 2008

Abstract

Microctonus caudatus parasitizes the adults of Harpalus rufipes. It is bivoltine, and its summer generation occurred in up to 27% of the study population of H.rufipes. The mean level of parasitism throughout both 1973 and 1974 was 8.4%.
Many larvae of M.caudatus are found in one host; the maximum number was 92, mean 20.8. There was indirect evidence of competition between larvae within the host, so that about sixty larvae, at most, were able to develop fully.
Larvae of the summer generation of M.caudatus emerged from host beetles between the end of July and mid September, invariably killing their host. The larvae pupated in the soil and adult parasites emerged from the pupal cocoons about 14 days later.
M.caudatus is parthenogenetic, and individuals oviposited readily in adult beetles in the laboratory. A culture of the parasite was maintained for almost a year at 15°C under artificial light of natural outdoor daylength, when four generations developed in the year. Time taken for development within the host was longest under short day conditions.
Aspects of the biology of Staphylinus olens (Müller), Britain's largest Staphylinid beetle
Authors: NIELD C. E. 
Published: March 2008

Abstract

Methods for rearing Staphylinus olens (Müller) (Col., Staphylinidae) are described, and development compared with other species of Coleoptera.
The distribution of S.olens over an area of Manchester is noted, and biological comparisons made with a laboratory population from South Wales. In the area sampled, most individuals live on well‐drained soils, possibly because successful pupation occurs under dry conditions.
‘Courtship’ and mating are described.
Egg‐laying, the egg, and its hatching are described, and compared with other coleopteran eggs.
Headwidths of laboratory larvae were recorded, and are compared with those of other beetle larvae.
Instars I and II lasted 44–45 days, although first instar larvae which eventually pupated had a mean duration of 33.5 days. Instar III averaged 102 days, but this time became shorter with later hatching, roughly synchronizing adult emergence.
Pupation and the obtect pupa are described. Pupal development took 32–37 days, after a 10–14 day prepupation period.
Newly emerged adults may construct winter burrows after autumn breeding. Second season adults may not hibernate, and often fail to survive another winter.
Food is manipulated by mandibles and legs, but no solids are consumed. Adults and larvae will eat many foodstuffs.
The nature of the mimetic patterns of the brassolid genera, Caligo and Eryphanis
Authors: STRADLING D. J. 
Published: March 2008

Abstract

The combination of cryptic and pseudaposematic patterns on the underside of the wings of the genera Caligo and Eryphanis is discussed.
It is suggested that in nature the false warning patterns resemble the profiles of amphibian and reptilian heads.
The possible protective value of these devices is discussed.
Searching by Adalia bipunctata (L.) (Coleoptera: Coccinellidae) and escape behaviour of its aphid and cicadellid prey on lime (Tilia×vulgaris Hayne)
Authors: WRATTEN S. D. 
Published: March 2008

Abstract

The paper describes the behavioural interactions between searching larvae of Adalia bipunctata and its aphid and cicadellid prey on lime (Tilia×vulgaris Hayne).
The frequency with which the predator achieves contact with cicadellid nymphs of differing ages is related to direction of predator approach and predator perception by the cicadellid.
The success of a coccinellid in contacting and capturing its aphid prey is related to the predator's size and direction of approach, the perception of the predator by an aphid and the latter's ability to escape, the effectiveness of which is discussed.
Sperm (ejaculate) competition in Drosophila melanogaster, and the reproductive value of females to males in relation to female age and mating status
Authors: BOORMAN E. , PARKER G. A. 
Published: March 2008

Abstract

In double mating experiments with Drosophila melanogaster in which one male had been irradiated, it was confirmed that sperm displacement is extensive, i.e. the second male to mate displaces most of the previously‐stored sperm.
The predominance of the second ejaculate over the first increases with the interval between the two matings, from about P2= 0.83 (second mating on the first day after the first mating) to about P2= 0.99 (interval between mating = 14 days) where P2 is the proportion of offspring fathered by the second male.
A more accurate method for calculating P2 values is developed for experiments in which sperm are ‘labelled’ by irradiation treatment (equation 1).
Observations of the reducing egg production of the female throughout life were also obtained. A model is examined which incorporates both the sperm competition and egg production data to predict the reproductive value to a male of a mating with a given type of female, varying in age and mating status. The relative value (in terms of probable numbers of progeny gained) of a mating with a virgin or 4 day post‐mating female is about twice that of a 14 day post‐mating female, mainly because of the fecundity difference.
Some evolutionary aspects of sperm competition and multiple mating in insects are reviewed and discussed.
The effect of prey density and host plant characteristics on oviposition and fertility in Anthocoris confusus (Reuter)
Authors: EVANS H. F. 
Published: March 2008

Abstract

Anthocoris confusus females show the greatest egg production when fed on eight adult Aulacorthum circumflexus per day. Prey densities below six result in a marked fall off in egg production.
Low prey densities result in reduced egg fertility and a decrease in oviposition period.
A.confusus females oviposit on those parts of a broad bean plant which support the highest aphid densities. This increases the probability of survival of the emerging nymphs.
Females are also able to distinguish between young, fully turgid, plants and older, more flaccid, plants and oviposit preferentially in the younger ones. Thus the eggs develop before the plant dies.
Design and elevation of sex‐attractant traps for pea moth, Cydia nigricana (Steph.) and the effect of plume shape on catches
Authors: LEWIS T. , MACAULAY E. D. M. 
Published: March 2008

Abstract

Catches of male pea moths in six designs of trap, each containing (E,E)‐8,10‐dodecadienyl acetate as an attractant, were compared; triangular‐shaped traps caught most moths.
The vertical distribution of moths within a pea crop and the size of catches at different levels varied in different wind speeds. Three‐quarter crop height is probably the optimum height for monitoring.
Five trap designs (including the triangular type) captured only 20–30% of individuals landing on them; water traps were slightly more efficient.
There was an eight‐fold range in the number of moths caught depending on the sticky material used. ‘Bird‐Tanglefoot’ was most effective.
Smoke plumes, emitted from different trap designs in the field to simulate plumes of attractant, were photographed and measured. The effect of trap design on plume shape was confirmed in wind tunnel tests.
Field tests showed that the more elongated the mean plume emitted from a trap the greater the catch.
The tracks of individual moths flying to traps are discussed in relation to current views on orientation to odour sources.
Observations on the biology of Subcoccinella vigintiquattuor‐punctata (L.) in southern England
Authors: RICHARDS AOLA M. , POPE R. D. , EASTOP V. F. 
Published: March 2008

Abstract

Subcoccinella 24‐punctata (L.) is exclusively phytophagous, and is widely distributed throughout Britain.
Under laboratory conditions the duration of pre‐adult instars is about 6 weeks. Adults appear from the end of June onwards. Many enter reproductive diapause at the end of July, but remain active till the end of October.
Reproductive diapause is determined by the interaction of photoperiod and temperature.
Hibernation is unstable, and there may be high mortality in overwintering adults. These finally die during May and June.
The cool temperate climate limits the population size, preventing it from reaching pest proportions.
Biology of the Collembola Xenylla grisea Axelson and Lepidocyrtus cyaneus f. cinereus Folsom
Authors: SHARMA G. D. , METZ L. J. 
Published: March 2008

Abstract

Xenylla grisea Axelson and Lepidocyrtus cyaneus f. cinereus Folsom were reared on brown whole wheat flour in culture jars containing a base of plaster of paris and charcoal.
Sexes in X.grisea may be differentiated by the combination of three characters: length, colour and body shape. No parthenogenesis was observed in either species.
At room temperature (25–27°C), females of X.grisea began laying eggs after the fourth moult and required 10–15 days (mean of 12.6) to reach sexual maturity from the day of hatching. With L.cyaneus f. cinereus, average periods from hatching to maturity were 16.8, 27.4 and 43.2 days at temperatures of 26.5, 22 and 15°C, respectively.
The degree of oligophagy in Locusta migratoria (L.)
Authors: BERNAYS E. A. , CHAPMAN R. F. , MACDONALD J. , SALTER J. E. R. 
Published: March 2008

Abstract

Locusta migratoria in the field feeds mainly on grasses, including cultivated species, but there are numerous reports of feeding on other monocotyledons. Feeding on dicotyledons is reported, but in many cases non‐grasses are only accepted in the absence of grasses. Previous laboratory work also indicates that grasses comprise the main food, though other plants are eaten.
Field observations on nymphal bands in Australia show that the insects select grasses within the habitat; dicotyledons are generally rejected.
The feeding response to 209 species of plants from fifty‐six families was tested. The grasses and some Cyperaceae and Juncaceae were generally fully eaten. Some other monocotyledons, such as palms, were also accepted though only small amounts were eaten; orchids and lilies were rejected. Very few dicotyledons were eaten. The dicotyledons which were eaten after 5h without food were rejected after only 1 h; the grasses were readily accepted after the shorter interval
The degree of oligophagy depends on the choice of food available and the time for which the insect has been deprived of food and water. Grass is normally eaten if available; in its absence, insects which have been without food for some hours will feed on a wide range of plants, but the amounts eaten are usually small.
Absolute estimates of larval populations of culicid mosquitoes: comparison of ‘capture‐recapture’, ‘removal’ and ‘dipping’ methods
Authors: CROSET H. , PAPIEROK B. , RIOUX J. A. , GABINAUD A. , COUSSERANS J. , ARNAUD D. 
Published: March 2008

Abstract

Four sets of experiments were devised to evaluate the absolute size of aedine larval populations. Three methods were used and compared: ‘capture‐recapture’, ‘removal’ and ‘dipping’ methods.
The results show that ‘dipping’ gives estimates of population size similar to those obtained with the two other methods, providing that a strict procedure is followed.
Since the ‘dipping’ technique is particularly easy, the results offer new possibilities for the study of population dynamics in Culicidae.
Ecological significance of wing polymorphism in Fulgoroidea which inhabit tidal salt marshes
Authors: DENNO R. F. 
Published: March 2008

Abstract

The vegetation of New Jersey tidal salt marshes is composed primarily of two grasses, Spartina patens, which occupies a narrow elevational zone of high marsh and varies little in structure from site to site, and Spartina alterniflora, an intertidal species which occurs as two spacially separated growth forms (tall and short). Fulgoroids, polymorphic for wing length, inhabit these grasses.
Populations of the common fulgoroid inhabiting short form S.alterniflora were composed of equal numbers of macropters and brachypters. Mesothoracic wings of brachypters were subequal in length to the abdomen allowing for short but inefficient flights compared to macropters.
Fulgoroids residing in S.patens produced mostly brachypters having small meso‐and vestigial metathoracic wings and were incapable of flight.
Brachypter density of all fulgoroids was correlated with the seasonal increase in biomass of the host grass, while macropter density was not.
Peak macropter density occurred shortly before maximum biomass of the host grass was attained.
The production of macropterous forms was correlated with high levels of crowding incurred during nymphal stages.
Spatial and temporal variation in the structure of the host grasses and habitat reliability are suggested as important factors dictating the wing‐polymorphism strategies of fulgoroids.
Species of Culicoides breeding on rocks and riverbanks in Nigeria
Authors: DIPEOLU O. O. , OGUNRINADE A. F. 
Published: March 2008

Abstract

Catches of Culicoides made on a rocky hill and river bank in south‐western Nigeria showed Culicoides grahami and C.distinctipennis to be dominant. The former was most active at dusk and the latter at dawn.
The number of matured eggs in the gravid female Culicoides caught on the hill and riverbank was low compared with those in gravid females of the same species caught around livestock.
The fat bodies of all the dissected nulliparous and newly emerged Culicoides were full and large; those of the parous ones were depleted and inconspicuous except in individuals caught between June and July. The crop of most of the adult Culicoides contained colourless to dark yellowish fluid.
C.grahami was the most numerous of the newly‐emerged species followed by C.distinctipennis.
On the rocky hill, Culicoides bred in rotholes and boggy ground in between the rocks; at the river bank, breeding sites were underneath partially waterlogged canoes, in crabholes and other crevices, and underneath rotten vegetation.
The influence of rainfall on the Culicoides population is discussed. Most of the species had adapted themselves to nectar feeding and autogeny was common. Perhaps some species aestivate during the hot dry season.
Diel periodicity in the adult eclosion of the blackfly, Simulium damnosum Theobald, in the Ivory Coast
Authors: EDWARDS A. J. , TRENHOLME A. A. G. 
Published: March 2008

Abstract

The timing of adult eclosion in forest zone blackflies of the Bandama cytotype of the Simulium damnosum complex in the Ivory Coast was investigated both in the field and laboratory.
An eclosion trap and a simple technique for keeping black‐fly pupae in the laboratory are described.
Hourly collections of newly emerged S.damnosum adults showed that there was an eclosion peak at 05.30–06.30 hours in the field and at 07.00–08.00 hours in the laboratory. Approximately 30% of the blackflies in the field emerged at 06.00–06.30 hours.
S.damnosum kept under natural light‐dark conditions in the laboratory did not show any delay in the timing of the eclosion peak, relative to that of the first day in the laboratory, until the third day of the experiment.
The area of discovery and searching strategy of a primary parasite and two hyperparasites
Authors: KFIR RAMI , PODOLER HAGGAI , ROSEN DAVID 
Published: March 2008

Abstract

Two hyperparasites, Cheiloneurus paralia (Walker) and Marietta exitiosa Compere, of Microterys flavus (Howard), a primary parasite of the brown soft scale Coccus hesperidum L. have been studied.
The area of discovery of the hyperparasites for secondary hosts (scale insects) is greater than that of the primary parasite, indicating higher searching efficiency of the secondary parasites.
Cheiloneurus has a higher searching efficiency measured as its area of discovery for discovering both the secondary (scale insect) and the primary (Microterys) hosts, as compared with Marietta.
The searching efficiency of Cheiloneurus increased in the presence of its own males.
In each species there is a non‐linear relationship between the searching efficiency and female density.
Cheiloneurus and Marietta present two differing searching strategies. Cheiloneurus tends to exploit as many primary hosts as possible in each secondary host encountered, whereas Marietta, tends to disperse its progeny more regularly by avoiding, to a certain extent, the exploitation of more than one host in each scale insect encountered.
Oviposition behaviour and food plant discrimination in leafhoppers of the genus Oncopsis
Authors: CLARIDGE M. F. , REYNOLDS W. J. , WILSON M. R. 
Published: March 2008

Abstract. 1. Field host plants of the six British species of Oncopsis are described. O. avellanae is unusual in being associated with both Corylus and Alnus.2. Laboratory experiments on nymphal feeding preferences, nymphal and adult survival, and adult oviposition preferences are described for all species, using Carpinus, Corylus, Alnus and Betula species as test plants.3. All experiments demonstrated considerable specificity in feeding, and especially oviposition.4. It is suggested that discriminative oviposition behaviour is the major determinant of observed field distribution patterns.
An analysis of the chalcidoid (Hymenoptera) fauna of a sand‐dune system
Authors: COPLAND M. J. W. , ASKEW R. R. 
Published: March 2008

Abstract. (1) 6449 chalcids representing 212 species, ninety‐six genera and eleven families were collected. The frequency of species and individuals did not fit a logarithmic series and Yule's index was chosen as a suitable index of diversity.(2) Species diversity of the total chalcid fauna in a zone was directly related to the number of flowering plants in the zone. However, Jaccard's coefficient of similarity between pairs of zones showed that there was little correlation between the similarity of zones based on the occurrence of plants and the presence of chalcids.(3) The Eulophidae and Pteromalidae showed two peaks of occurrence, the other families had only one. The times of peak occurrence varied on different zones and presumably reflected the main flowering period or some other seasonal aggregating factor.(4) Overall there was a higher female to male ratio. In a majority of the more common species the males were more aggregated than the females.(5) The overall sex ratio varied throughout the year, with a high female ratio at the beginning and end of the season. The Pteromalidae showed a greater fluctuation through the season and over the zones than the other families.(6) Several species were collected on the sand‐dunes although their known hosts were absent.(7) Thirteen rare species were captured.
Ecology of the parasites of a predatory bug, Blepharidopterus angulatus (Fall.)
Authors: GLEN D. M. 
Published: March 2008

Abstract. 1. On lime, Blepharidopterus angulatus is parasitized by a braconid, Peristenus sp., which is attacked by an ichneumonid hyperparasite, Mesochorus sp. The emergence and oviposition behaviour of the adult parasites and the growth of the larvae are described.2. Parasitized B. angulatus are considerably heavier at maturity than normal, and nymphs parasitized by Peristenus consume, during their fifth instar, 2.1 times more in dry weight of prey (lime aphids). The growth efficiency of Peristenus is 30–37%.3. An inverse relationship between percentage parasitism and host density on different trees may have been due to differences in synchronization.