摘要:

Abstract.1. The common cassidid beetle,Stolassp., feeds as both larva and adult on the leaves of the vine,Ipomoea asarifolia, a wild relative of the sweet potato.2. In the region around Manaus (Amazonas State, Brazil) an average of 86% of the egg clutches were completely parasitized by the eulophid,Emersonella niveipes.3. The wasp is phoretic on female beetles. In comparison with field beetles that lacked phoretic wasps, beetles associated with wasps produced eggs sooner, laid more egg clutches, and had a shorter laboratory life expectancy.4. Host discrimination by the wasp is probably an active process rather than a passive association with randomly encountered beetles.5.Emersonella niveipesalso attacksChelymorpha cassidea, a pest of sweet potato. Adults ofStolassp. do not feed on sweet potato foliage nor occur in sweet potato fields, so they could provide a useful innocuous alternate host forEmersonella niveipes.6. As some species in the Convovulaceae are important weeds in field crops, foliage‐feeding cassidid beetles may play a useful role in weed suppression. Any biological control programme for the suppression of sweet potato pests may favour the spread of those noxious weeds that share the herbivore fauna of sweet potatoe

ISSN:0307-6946    

DOI:10.1111/j.1365-2311.1978.tb00906.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

Abstract.1. Insect flotsam was obtained from marine pleuston samples from the English Channel (U. K.), off the Oregon coast (U. S. A.), and in the Gulf of California (Mexico).2. Only ten orders of insects were represented, Coleoptera, Diptera and Homoptera being the most abundant.3. Staphylinidae and Chironomidae were the most abundantly represented families taken from the English Channel, comprising 43% and 18% respectively of total insects sampled.4. Aphididae comprised 39% of the Oregon Coast samples.5. Aphididae (42%) and Cicadellidae (17%) accounted for 59% of the insects in the Gulf of California.6. Fish may feed on surface insects at night and this may account for the lower numbers found in early morning samples.

ISSN:0307-6946    

DOI:10.1111/j.1365-2311.1978.tb00907.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

Abstract.1. Examination of the ovaries of female olive flies (Dacus oleae) from wild populations on Corfu during the summer months of 1975 indicated that all were non‐gravid for a period of several weeks during June and July and the terminal follicles were resorbed.2. Experiments in outdoor cages indicated that olive fruits could stimulate ovarian development during the summer months.3. Experiments in constant temperature cabinets indicated that high temperatures (i. e. 26–29°C) in conjunction with a low humidity (45 ± 5°%) inhibited ovarian maturation.4. Whereas the presence of olive fruits offset the effects of temperature and humidity on ovarian development at 26°C in all flies, at 29°C very few were able to mature their ovaries.5. It is suggested that it is the interaction of temperature, humidity and access to fruit which determine when ovarian maturation ceases and recommences during the summe

ISSN:0307-6946    

DOI:10.1111/j.1365-2311.1978.tb00908.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

Abstract.1. In Seychelles,A. longipesnests on the ground and in trees, underground nests do not occur, possibly because soils are too hard or unstable.2. Nest density approached 700 ha‐1in some areas and nests contained, on average, about 4000 ants. The total population (including foragers) in heavily infested areas may exceed 10 millions ha‐1.3. On average, each nest contained about forty queens and fifty males, although only 50% of nests contained males. A few nests contained up to 300 queens, 1000 males, 36 000 workers and 23 000 brood.4. Production of sexual adults and brood was related to the wet season, most being produced shortly before or after the heavy rains from November to March.5. Natural spread is probably by budding of colonies which, during an expansive period, may advance 1 m day‐1.6. Food collected by the colony included sugary substances from fruits, honey‐dew‐producing insects and plant exudates, and proteinaceous material, mainly in the form of insect prey and carcases. A forager collected, on average, 1.2 mg of liquid or 2.8 mg of solid material on each foraging trip.7. Foraging occurred at fluctuating intensities throughout the day and night, but was limited by heavy rain, strong winds and substrate temperatures above 30°C. Maximum activity occurred at ground temperatures of 25–30°C and ceased about 44°C.8. Availability of food and nest sites proably have the greatest influence on p

ISSN:0307-6946    

DOI:10.1111/j.1365-2311.1978.tb00909.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

Abstract.1.G. spinigerlarvae repaired openings in their cells by excavating dung from the brood‐mass and placing it in the edge of the hole. Thrusting with the head sealed small holes but pushed dung away from larger defects. Sliding and somersaulting movements allowed repair of different parts of a defect. Repair was provoked by contact with the defect, not by changes in humidity.2. Dung excavated at the anterior end of the cell was transferred by somersaulting, and thrust into the posterior end to seal off foreign bodies. Burrowing by the larvae depended on similar behaviour which moved the whole cell within the brood‐mass.3. Larvae were sensitive to surface contact, making a coordinated attack on a source of stimulation. They also moved towards dung and wet soil.4. Fluid regurgitated by disturbed larvae killed blowfly larvae when injected, and repelled earthworms.5. To construct a pupal cell, excavated material was transferred by somersaulting and used to build a transverse partition without the usual vigorous thrusting movements. The ability to re‐initiate pupal cell formation was retained for about 4 days.6. Larvae enclosed in artificial brood‐balls enlarged defects while attempting to repair them, but larvae just prior to pupation taken from recently made pupal cells could repair such defects.7.Aphodius fossorlarvae rarely attempted to repair openings in their cells and usually escaped by burrowing (as above), but opening a recent pupal cell always provoked repair.8. Repair byG. spinigerlarvae is closely related to other larval activities but lacks several features that are important for repair by species developing in freestanding broo

ISSN:0307-6946    

DOI:10.1111/j.1365-2311.1978.tb00910.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

Abstract.1. The various groups of arthropods associated with rodent carrion during decay in temperate woodland and grassland habitats are described in each of four seasons.2. A distinction is drawn between those occurring by chance and those positively associated with the carrion.3. The role of these last in actually assisting the decay of the carcasses with which they are found is discussed. Despite the abundance and diversity of carrion‐frequenting species, few are involved to any significant extent in the release of carrion materials during decompositio

ISSN:0307-6946    

DOI:10.1111/j.1365-2311.1978.tb00911.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

Abstract.1. Population and physiological measurements were made on monarch butterflies in three overwintering colonies along the California coast during the 1975–76 season.2. Mark, release and recapture studies indicated that two northern colonies (Muir Beach and Santa Cruz) stabilized at maxima of about 40000 and 95 000 individuals with little movement in or out of colonies, whereas the southern one at Santa Barbara appeared dynamic with a maximum of about 45 000.3. Initially low, sexual activity builds to a massive mating ceremony in February, followed by rapid colony dispersal. The butterflies deteriorate gradually during the overwintering period, but males do so to a greater extent because of their involvement in frenzied courting flights.4. Changes in several parameters at the Muir Beach colony were measured between 1 November and 2 February. Right forewing length did not change with time, indicating no differential mortality with respect to size. However, both sexes lost about 25% of their total dry weight, and 49–60% of their lipid contents. Minimum fat levels were about 20 mg and some butterflies were as lean on arrival as were the most depleted overwintering survivors.5. The importance of nectaring in restoring lipid reserves is potentially great but remains uninvestigated. The hypothesis is put forward that the distance spring migrants are capable of flying is dependent largely upon their lipid reserves following the overwintering period. This and the intracolony mass‐mating ceremony are seen as randomizing factors which prevent geographic differentiation and allow the maintenance of the generalized, nature of the migration, which in turn enables the monarch to exploit the vast milkweed flora across the North American continent.6. Cardenolides also diminished during the wintering, but to a substantially lesser extent than the lipids. There was no evidence for a change in the proportion of cardenolide‐positive butterflies, suggesting no differential elimination by predation of the poison‐free palatable individuals. This is the first field evidence in support of the theory of automimicry.7. The overwintering behaviour of the monarch butterfly is seen as an integrative force in optimizing foodplant exploitation, reproduction, anti‐predator, and migration

ISSN:0307-6946    

DOI:10.1111/j.1365-2311.1978.tb00912.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

Abstract.1. We have explored the question of whether breadth of diet in moths is associated with adaptations other than host selection behaviour, with particular reference to body size.2. Generalist species in Britain and New York are larger than specialist species.3. This relationship is probably not due to latitudinal clines, nor to higher fecundity in generalist species.4. We suggest that the large bodies of generalists buffer them against environmentally‐induced physiological stres

ISSN:0307-6946    

DOI:10.1111/j.1365-2311.1978.tb00913.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

Book reviewed in this article:THEORY AND PRACTICE OF BIOLOGICAL CONTROL. Edited by C. B. Huffaker and (the late) P. S. MessengerTHE LIFE OF BEETLES. By Glyn Evans

ISSN:0307-6946    

DOI:10.1111/j.1365-2311.1978.tb00914.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY