bluuebunny/crossref_metadata_2025 huggingface dataset:
Who controls the rhythm of tsetse parturition: mother or larva?
Authors: DENLINGER DAVID L.
Published: March 2008

ABSTRACT. In constant light or constant darkness, Glossina morsitans morsitans Westwood were found to exhibit no obvious rhythms of parturition, but in LD 12:12 most larvae were deposited during the photophase. When a divided photoperiod chamber was used to expose the female's head to LD 12:12 and the abdomen (containing the larvae in utero) to constant light, parturition coincided with the photophase of the female's head. But, if the abdomen was exposed to LD 12:12 and the female's head received constant light or was painted with black enamel, parturition coincided with the photophase of the larva. When the female's head and abdomen both received LD 12:12 but 11 h out of phase with each other, parturition was equally frequent in each 12h fraction. The results thus suggest that both the mother and larva are capable of entraining the rhythm, and that in a normal pregnancy both participate in establishing the rhythm.
Wind tunnel studies on the effects of secondary sex pheromone components on the behaviour of male Egyptian cotton leafworm moths, Spodoptera littoralis
Authors: HAINES LINDA C.
Published: March 2008

ABSTRACT. The responses of adult male Spodoptera littoralis (Boisd.) (Noctuidae) to components of the female sex pheromone were examined in a wind tunnel. The responses of male moths from both Egyptian and Cretan stocks to the primary ‘attractant’ (Z, E)‐9,11 tetradecadienyl acetate (III), were compared with the responses to III combined with various percentages of the secondary components tetradecyl acetate (I), (Z)‐9‐tetradecenyl acetate (IIA), (E)‐11‐tetradecenyl acetate (IIB), IIA and IIB combined, and(Z, E)‐9,12‐tetradecadienyl acetate (IV). Analysis of the flight behaviour recorded on videotape showed that with one exception (IV), the secondary components increased the males' success in reaching the source and increased the length of time they spent at the source. In most cases, increasing the relative percentage of the secondary component caused a reduction in the number of males responding. The results are compared with those obtained in field trials with S.littoralis.
Host deprivation influence on response of Rhagoletis pomonella to its oviposition deterring pheromone
Authors: ROITBERG BERNARD D. , PROKOPY RONALD J.
Published: March 2008

ABSTRACT. The response of host‐depibved Rhagoletis pomonella Walsh (Diptera, Tephritidae) females to host fruit (Crataegus viridis L.) marked with R.pomonella oviposition deterring pheromone was measured in the laboratory. A positive correlation was found between length of host deprivation (5, 10, 20, 40 or 80 min) and probability of host acceptance (i.e. oviposition) by flies. The results are discussed in relation to current theories on physiological control of insect feeding and oviposition behaviour.
Ecdysteroid production during caste differentiation in larvae of the ant, Plagiolepis pygmaea
Authors: SUZZONI JEAN‐PIERRE , PASSERA LUC , STRAMBI ALAIN
Published: March 2008

ABSTRACT. Variations in ecdysteroids were measured by radio‐immunoassay in worker‐biased and queen‐biased larvae of the ant Plagiolepis pygmaea Latr. (Hymenoptera, Formicidae) during late larval development, i.e. from the end of winter diapause up to the prepupal period. At the end of diapause, larvae are bipotential and, depending on culture conditions, can become either queens or workers. Ecdysteroid profiles revealed that there are striking differences between the two castes: worker larvae showed high titres during their development, queen larvae had low titres over the same period.
An airflow olfactometer for measuring olfactory responses of hymenopterous parasitoids and other small insects
Authors: VET LOUISE E. M. , LENTEREN J. C. VAN , HEYMANS M. , MEELIS E.
Published: March 2008

ABSTRACT. A new type of airflow olfactometer is described, and results given of experiments using it to measure behavioural olfactory responses of hymenopterous parasitoids. Compared with Y‐tube olfactometers it shows several advantages. In its exposure chamber four separate abutting odour fields are presented so that the test insect can readily enter and re‐enter them. More than one odour (or different concentrations of one odour) can be tested at the same time, thereby providing complex preference test situations. The various behavioural measures that can be assessed in the apparatus are examined and discussed.
Visual course control of escape responses in the cockroach Blaberus craniifer: role of internal and external orientation information
Authors: BELL WILLIAM J. , TOBIN THOMAS R. , VOGEL GREGORY , SURBER JAMES L.
Published: March 2008

ABSTRACT. Nymphs of Blaberus craniifer were exposed to a point source of light while walking on a servosphere apparatus. The initial response was a brief stop followed by running at a rate exceeding that in darkness. Their course was away from the light source and their direction became closer to 180° away from the light, as the light source approached the horizontal. The straightness of the course was controlled by both internal and external orientation information. If the source was overhead the course was more circuitous than with the directional light. Following a temporal switch from darkness to light, abrupt sharp turns of more than 90° led the animals back into a ‘zone of darkness’. Stopping occurs immediately after the onset or offset of the light stimulus, but the duration of stops does not seem to be correlated with the time since a previous stop, nor with the length of the run prior to a stop. Responses to a sudden onset of a light stimulus seem to represent adaptations for re‐locating a ‘zone of darkness’ and for predator avoidance when a cockroach is disturbed during its photophase.
Electronic fraction collector used for insect sampling in the photoperiod‐induced diel emergence of bark beetles
Authors: BYERS JOHN A.
Published: March 2008

ABSTRACT. An electronic timer and fraction collector consisting of CMOS integrated circuits is described. It converts 50‐ or 60‐Hz AC to real‐time pulses in programmable whole‐number increments (1, 10 or 60s) from 3 to 16659, producing timing periods from 3 s to more than 11 days. The fraction collector contains a leaf‐switch feedback circuit that automatically adjusts to various gear motor speeds and sample tube spacings so that proper positioning results. Hourly collections by the device of the bark beetles Ips typographus L. and Pityogenes chalcographus L. (Scolytidae) emerging from logs of Norway spruce, Picea abies, indicated that both species emerged with a diel periodicity. A unimodal emergence peak for both sexes of both species occurred at midday in LD 20:4 at a constant 25°C and 80% r.h.
The role of chemoreception in sex recognition by male crickets: Acheta domesticus and Teleogryllus oceanicus
Authors: HARDY TAD N. , SHAW KENNETH C.
Published: March 2008

ABSTRACT. Contact chemoreception is important in female recognition by Teleogryllus oceanicus (Le Guillou) males. Antennal contact of female conspecifics, body regions, detached antennae and conditioned substrate elicited mostly courtship responses including courtship songs. Aggressive acts were produced only in response to male conspecifics. Male body regions, detached antennae and conditioned substrate elicited very few courtship or aggressive acts and no songs. This suggests that one or several communication modes, in addition to chemical communication, are necessary to elicit aggressive responses. Acheta domesticus (L.) males cannot rely upon chemical cues for recognition of either sex. Responses to conspecifics suggest that A. domesticus males produce aggressive acts immediately after antennal contact with either sex. Aggressive response to males usually persists, but response to females often switches to courtship. Responses to body regions, detached antennae, and conditioned substrate were few, with courtship and aggressive responses elicited by both male‐ and female‐generated stimuli. The importance of contact chemoreception in cricket communication is suggested by (1) failure of hexane‐washed antennae to elicit aggressive or courtship acts, and (2) males spending more time in contact with body regions and conditioned substrates than with corresponding controls. Lack of response to male or female odour‐laden air suggests that chemical signals are used by males only if directly contacted. Chemical and other signals supplement the obvious use of acoustic signals for intra‐ and intersexual communication in these crickets. The importance of multimodal communication in sex recognition is discussed.
Photoperiodic control of reproduction in the milkweed leaf beetle, Labidomera clivicollis
Authors: PALMER JAMES O.
Published: March 2008

ABSTRACT. Photoperiod significantly affected reproduction in a central Texas population of the milkweed leaf beetle Labidomera clivicollis (Kirby) (Chrysomelidae). Laboratory reared beetles responded to a critical photoperiod of LD 12.5: 11.5; longer photoperiods induced reproduction, while shorter photoperiods induced diapause. Both larval and adult stages exhibited sensitivity to photoperiod. Beetles exposed to long days as adults reproduced regardless of photoperiod experienced as larvae. However, exposure to long days, as larvae but short days as adults also induced reproduction in an intermediate portion of the population. No larval instar appeared to be more sensitive than the others, and the proportion of the population responding did not increase with cumulative larval exposure to long days. Larval sensitivity to photoperiod may be ecologically significant to central Texas populations because it permits a substantial portion of the autumn generation to initiate a third generation in favourable years.
Diel organization of behaviour in milkweed bugs, Oncopeltus spp.
Authors: ALDEN BETH , DINGLE HUGH , POSSIDENTE BERNARD
Published: March 2008

ABSTRACT. Daily cyclic activities in various behaviours were similar in three species of tropical Oncopeltus (Heteroptera, Lygaeidae). Opposition in females and general movement in both sexes peaked in the middle to late light period. In contrast, feeding and mating peaked at the end of the light period and the beginning of the dark respectively. Other behaviours also tended to display one or the other of these patterns. The diel timing of behaviour observed in this study essentially duplicated the periodicities of a migratory population of Oncopeltus fasciatus from Iowa. The similarity of results across species and populations suggests a general pattern for the genus which probably serves to synchronize behaviours with environmental cycles and appropriate physiology. This similarity is interesting in view of the broad geographical range of the genus across both temperate zone and tropics and in view of the differences among populations with respect to photoperiodic determination of diapause.
Growth and development of the endoparasitic wasp Apanteles congregatus: dependence on host nutritional status and parasite load
Authors: BECKAGE NANCY E. , RIDDIFORD LYNN M.
Published: March 2008

ABSTRACT. Previously we have shown that the number of Apanteles congregatus Say (Hymenoptera, Braconidae) larvae developing in Manduca sexta (L.) (Lepidoptera, Sphingidae) larvae that are parasitized in the first instar determines the timing of emergence of the parasites from the host. Here we show that the first larval ecdysis of the wasps occurs after the host ecdyses to the terminal stage, regardless of whether that stage is the host's fourth, fifth or supernumerary sixth instar. Starvation of newly ecdysed terminal stage host larvae prevents emergence of the parasites. When starvation is begun at progressively later times, then an increasing proportion of the hosts have parasites that emerge, suggesting a period of indispensable host nutrition exists during which the host must feed to satisfy the developmental requirements of the parasites. In hosts fed ad libitum, the weight of the host plus its parasites at the time of emergence is positively correlated with the number of parasites developing in the host. When the weight of the parasites alone is subtracted from the weight of the host—parasite complex, the data show that heavily parasitized hosts have a larger host mass than lightly parasitized larvae. In contrast, the wasp larvae, and the adult males and females that develop from them, have lower individual weights after development in heavily parasitized hosts.
Circadian rhythm of the locomotor activity in Drosophila melanogaster and its mutants ‘sine oculis’ and ‘small optic lobes’
Authors: HELFRICH CHARLOTTE , ENGELMANN WOLFGANG
Published: March 2008

ABSTRACT. The locomotor activity patterns of wildtype Drosophila melanogaster and the mutants so (sine oculis) and sol (small optic lobes) were investigated. In all strains the proportions showing circadian rhythmicity, arrhythmicity and more complex patterns which could not be thus classified were similar. The occurrence of abnormal activity patterns is thus not a property of the mutation as previously claimed (Mack & Engelmann, 1981). In flies with a distinct circadian rhythmicity, the period lengths (τ) varied between strains, τ for wildtype Italy and the mutant so was longer than for wildtype Berlin and the mutant sol. As different τ's have been reported by others, τ does not seem to be closely determined for Drosophila melanogaster. Many flies exhibited two rhythms simultaneously, one with τ shorter and one with τ longer than 24 h, apparently implying two‐oscillator control of the locomotor activity. The eyeless so mutants were entrained by LD cycles, so the compound eyes are not necessary, and so must possess the relevant photoreceptor(s) elsewhere. This may therefore also be true for the wildtype. Histology of the so adults revealed no correlation between the degree of reduction in the medulla and the occurrence of abnormal activity patterns. Since the only structures common to the medulla of so and sol are known to be large tangential cells, it is concluded that either they are of importance for the rhythmic system, or the oscillator(s) controlling locomotor activity is (are) not located in the medulla.
Ontogeny of the circadian system governing ecdysial rhythms in a holometabolous insect, Diatraea grandiosella (Pyralidae)
Authors: TAKEDA MAKIO
Published: March 2008

ABSTRACT. Three eclosion rhythms of Diatraea grandiosella Dyar (Lepidoptera, Pyralidae) showed different phase relationships to the LD cycle, different degrees of synchronization and different sensitivity to a brief light perturbation. Egg hatching occurred mainly at dawn, whereas pupation and adult emergence occurred mainly at dusk. The egg hatching was the most synchronized rhythm of the three, pupation the least. The egg hatching rhythm was more sensitive to a brief light perturbation than was the adult emergence rhythm. A light pulse in the middle of the night caused greater disturbance in the egg hatching rhythm than did a pulse placed in the early night. The three rhythms persisted in both DD and LL. LL free‐running rhythm gradually became desynchronized and broke down at the third cycle. The phase relationships reveal difficulties in applying the ‘external coincidence model’ to this species' photoperiodic response.
Responsiveness of Pseudaletia unipuncta males to the female sex pheromone
Authors: TURGEON JEAN J. , McNEIL JEREMY N. , ROELOFSt WENDELL L.
Published: March 2008

ABSTRACT. In wind tunnel experiments male response to different concentrations of synthetic pheromone varied with age. At 25°C responsiveness increased up to day 5 and then declined slightly on day 7. For any given age the level of response generally increased with an increase in pheromone concentration. Males held at 15°C (since emergence) showed a continual increase in responsiveness with age; however, overall response levels were less than at 25°C. At 25°C male response to low concentrations of pheromone (10 and 30 μg) varied markedly over a 24 h period but no differences were observed at higher concentrations (100 and 300 μg).
Surface chemistry of Sorghum bicolor and its importance in feeding by Locusta migratoria
Authors: WOODHEAD SUSAN
Published: March 2008

ABSTRACT. Seedling Sorghum bicolor cv.65D was rejected at palpation by nymphs of Locusta migratoria L. unless the surface wax was removed. The wax by itself was unpalatable, and when fractionated chromatographically into constituent chemicals its deterrent effects were attributable to the p‐hydroxybenzal‐dehyde, n‐alkane, and ester fractions. Analysis of these last two fractions showed that they were unusual in that the carbon chain lengths of the molecules were shorter than expected from previous literature, and it was these smaller molecules (tested as pure chemicals) that were repellent to L.migratoria. The short‐chain esters are more volatile than the ineffective longer‐chain ones, and it is proposed that the insect may detect these chemicals by short‐range olfaction and hence reject the plant before biting, thus imparting a more effective defence to the plant.
Influence of femoral chordotonal organ afferences on ecdysis and on the development of motor programmes in locust larvae
Authors: BÄSSLER U.
Published: March 2008

ABSTRACT. The receptor apodemes of the femoral chordotonal organs of hind legs of locust larvae were crossed. This reverses the sign of the chordotonal organ afferences. Animals were operated during the second, third and fourth instars and some could be reared to adults with the receptor apodeme remaining crossed. During walking, the animals did not habituate to the incorrect afference, but those operated at the beginning of the third instar altered their walking programme to some extent. The results from animals operated during the second instar and the first 2 days of the third instar were ambiguous. The jumping generator is not affected by the incorrect afference.
Deuterium oxide alters pupal diapause response in the flesh fly, Sarcophaga crassipalpis
Authors: ROCKEY SARAH J. , DENLINGER DAVID L.
Published: March 2008

ABSTRACT. Deuterium oxide averts pupal diapause in the flesh fly Sarcophaga crassipalpis Macquart when fed to larvae or when applied topically to photosensitive embryos exposed to short daylength. Deuterium oxide was not effective in promoting diapause when presented to embryos or larvae reared at long daylength. The effect of deuterium oxide appears to be cumulative in the larval state: increasing exposure time progressively reduces diapause response. If flies reared on deuterium oxide are exposed to continuous darkness, the diapause response remains high, thus implying that the physiological capacity for diapause is not disrupted. We suggest that deuterium oxide exerts its effect on the circadian rhythm controlling diapause induction.
Ovarian development in mosquitoes: stages of growth and arrest, and follicular resorption
Authors: CLEMENTS A. N. , BOOCOCK M. R.
Published: March 2008

ABSTRACT. Christophers' stages of ovarian development are elaborated and redefined to provide a more useful descriptive tool for mosquito physiology. Vital staining is advocated to help identify the earliest stages of vitellogenic follicles. By use of vital staining it has been confirmed that in Aedes aegypti (L.) early vitellogenic ovaries contain negligible numbers of dormant follicles, and that fecundity is correlated with food intake by regulated resorption of developing follicles. The concept of developmental gates in mosquito oogenesis is discussed.
Innervation of the cercal sensilla on the ovipositor of the Australian sheep blowfly (Lucilia cuprina)
Authors: MERRITT D. J. , RICE M. J.
Published: March 2008

ABSTRACT. The ovipositor of the female sheep blowfly, Lucilia cuprina (Wied.) (Diptera: Calliphoridae), has a complement of cercal sensilla that includes long, medium and short tactile hairs, two campaniform domes, four olfactory pegs, and ten double‐channelled gustatory hairs. This sensory array is suited to assess oviposition site resources, prior to and during the laying of an egg batch.

The tactile hairs and campaniform sensilla are each innervated by a single, tubular body containing dendrite. The olfactory pegs are each innervated by a single, moderately branched dendrite, which gains access to the external environment via pores at the bottom of deep grooves in the peg wall. The gustatory hairs fall into two categories. Four hairs have a single, tubular body containing dendrite at their base, and four unbranched dendrites running up to the hair tip which has a terminal pore. Six of the taste hairs have no tubular body containing dendrite at the base, and three unbranched dendrites running up to a terminal pore.
Characterization of galeal chemosensilla in the adult Colorado beetle, Leptinotarsa decemlineata
Authors: MITCHELL B. K. , HARRISON GLENN D.
Published: March 2008

ABSTRACT. Approximately fifteen gustatory sensilla are present on the galeae of adult Colorado potato beetle, Leptinotarsa decemlineata Say (Coleoptera: Chrysomelidae). In the SEM, these sensilla are not distinguishable morphologically, but some of them differ physiologically. All are sensitive to sucrose, while only a few respond to gamma amino butyric acid (GABA). One, called the alpha sensillum, is significantly more sensitive to GABA than the others. The same sensory cell predominates in the alpha sensillum responses to GABA and sucrose. This example of differential specificity among sensilla, in an apparently uniform sensory field, is discussed.
Venom as an interspecific sex pheromone, and species recognition by a cuticular pheromone in Paper Wasps (Polistes, Hymenoptera: Vespidae)
Authors: POST DAVID C. , JEANNE ROBERT L.
Published: March 2008

ABSTRACT. The venoms of Polistes fuscatus (subspecies fuscatus) (F.) and P. exclamans Viereck from sympatric populations in North Carolina, U.S.A., contain a pheromone which attracts males and stimulates sexual behaviour in both conspecific and heterospecific males. Males of P. fuscatus (subspecies variatus Cresson), a subspecies from Wisconsin, respond to venom of P. fuscatus fuscatus, P. exclamans, and Vespula maculifrons (Buysson) from North Carolina, although the levels of response to P. exclamans and V. maculifrons venom are less than that to P. fuscatus variatus venom.

Caged Wisconsin P. fuscafus males do not attempt to mate with P. exclamans females, but will attempt to mate with conspecifics. A series of bioassays indicates that males discriminate between females of P. fuscatus and P. exclamans on the basis of chemical, rather than behavioural or visual cues. The venom apparently is not important in species recognition. Instead, the results of two sets of bioassays suggest that species recognition is mediated by a surface pheromone on the cuticle of females.
Ultrasonic mate calling in the lesser wax moth
Authors: SPANGLER HAYWARD G. , GREENFIELD MICHAEL D. , TAKESSIAN ALEX
Published: March 2008

ABSTRACT. The lesser wax moth, Achroia grisella (Fabricius) (Pyralidae: Galleriinae), uses an altrasonic communication system for mate calling The male produces a 100 kHz sound by striking its tegula with the forewing. This calling sound induces virgin females to orient toward males. Although the pheromone released from the male's wing glands may stimulate kinesis in females, it does not elicit orientation. Female moths are attracted toward synthetic 40 and 72 kHz sounds which simulate the pulse length and repetition rate of the male's calling signal.
Changing visual responsiveness in pregnant and larvipositing tsetse flies, Glossina morsitans
Authors: ABDELKARIM E. I. , BRADY JOHN
Published: March 2008

ABSTRACT. Direct observations on the spontaneous activity and visually‐evoked responses of pregnant female Glossina morsitans morsitans Westw. were made hourly during the photophase over the 4 days around larviposition. Visual stimulation was by a 5d̀‐wide vertical black stripe moving laterally, 4 times min‐1 at c. 5d̀ s‐1. The numbers of take‐offs and the numbers of females taking off were recorded, both in response to the stimulus and spontaneously in its absence. The visual responsiveness paralled both the day‐to‐day changes and the altered circadian patterns of spontaneous activity reported previously (Brady & Gibson, 1983), being very low for the 48 h before parturition. It did not, however, rise in parallel with the increase in spontaneous activity during the last 3–4 h before parturition, and the proportion of flights oriented towards the moving stripe was also much reduced at that time. The significance of this changing responsiveness to slow movement is discussed, and its potential enhancement of any behavioural avoidance of aerosol, non‐residual insecticide spraying during late pregnancy is noted.
Foliar form influences ovipositional behaviour of the onion fly
Authors: HARRIS M. O. , MILLER J. R.
Published: March 2008

ABSTRACT. When presented with dishes containing a range of ‘foliar’ shapes, the onion fly, Delia antiqua (Meigen), laid the most eggs around narrow (4 mm) vertical cylinders. Response to cylinders diminished when their diameter was increased or decreased, when cylinder height was reduced to less than 2 cm, and when cylinder/substrate angle deviated from 90d̀. Differences in egg numbers on stimulatory and non‐stimulatory forms reflected primarily differences in post‐alighting pre‐ovipositional behaviours. Females alighting on narrow vertical cylinders initiated and completed stem runs rapidly and without interruptions, and frequently went on to probe and oviposit. Females alighting on other shapes, or larger, smaller, or non‐vertical cylinders, either did not initiate or did not complete stem runs, or did not go on to probe after completing a stem run. Such females rarely oviposited. Possible causes of such examining behaviours are discussed.
Increase in respiratory rate during feeding in larvae of the cinnabar moth Tyria jacobaeae
Authors: McEVOY PETER B.
Published: March 2008

ABSTRACT. This study tested the effect of diet and phase of the feeding cycle on oxygen consumption by fifth‐instar larvae of the cinnabar moth Tyria jacobaeae (L.) (Lepidoptera: Arctiidae). There was no significant variation in respiratory rates among larvae fed different diets, which were floral parts, upper, middle and lower leaves of the host plant tansy ragwort, Senecio jacobaea. The respiratory rates (x̄x± 95% Cl μlO2h‐1) of feeding larvae (279.5 ± 30.9) were higher than those of larvae at rest (179.7 ± 12.2), but were not significantly different from those of larvae in the post‐ingestive phase (272.8 ± 35.8).

The respiratory rates of feeding larvae increased linearly with the ingestion rate, such that an additional 21.1 μl O2 were consumed for every mg dry mass of plant material eaten per hour.
Diuretic hormone: another peptide with widespread distribution within the insect CNS
Authors: MORGAN P. J. , MORDUE W.
Published: March 2008

ABSTRACT. Diuretic hormone is a peptide neurohormone of as yet unknown chemical structure. Attempts to characterize the locust hormone have concentrated on the storage lobes of the corpora cardiaca as a source of material. Bioassay data now indicates that the occurrence of diuretic activity is more widespread in the locust CNS. Dose‐response curves indicate that the levels of the diuretic factor(s) in the brain, sub‐oesophageal and thoracic ganglia are remarkably similar to those found in the corpora cardiaca; activity was also detected in the abdominal ganglia (1–5) and terminal abdominal ganglion. Reverse‐phase HPLC has confirmed that the diuretic material found in the various parts of the CNS is chemically similar to at least one of the diuretic factors separated from the corpora cardiaca. The significance of the widespread distribution of this peptide hormone is considered.

Recent evidence of other workers has indicated the possible structural similarity between vertebrate vasopressin and the diuretic factor in the locust sub‐oesophageal ganglion. Chromatographic criteria have been used to demonstrate that the diuretic hormones isolated in our work are not vasopressin‐like molecules, but are chemically distinct entities.
Observations on the effect of photoperiod on the control of polymorphism in Psylla pyricola
Authors: MUSTAFA T. M. , HODGSON C. J.
Published: March 2008

ABSTRACT. Psylla pyricola Forster (Homoptera) occurs as two adult morphs, a summer form (f. typica) and a winter form (f. simulans). The latter is larger, darker and overwinters in ovarian diapause. Eggs laid by either morph under LD 12:12 (short days) or under LD 18:6 or 16:8 (long days) gave f. typica when reared under long days. When reared under short days, almost all were f. simulans. No interforms were recorded. When the photoperiod was switched during the nymphal stage (whether from long to short days, diapause induction; or from short to long days, diapause termination), nymphs were progressively less sensitive with increasing age, with no morph changes when the switch occurred in the fifth instar. Nymphs derived from f. simulans reared under long days tended to be more sensitive to a change to short days in the early instars than when the nymphs were first reared under short days and then switched to long days. Interforms were frequent when the switch occurred during the nymphal stage, particularly in the third instar. Wing lengths varied within morphs depending on the timing of the switch. The largest f. simulans were derived from f. typica when maintained under short days, and the smallest f. typica from either morph when maintained under long days, as would be expected under field conditions. No f. simulans were found under field conditions in the first f. typica generation, but a small percentage were present in the second generation. It is concluded that, even within a given generation, not all P. pyricola are equally sensitive to photoperiod, but that photoperiod is one of the major factors controlling the change to f. simulans in the autumn. Whilst under laboratory conditions photoperiod can also affect the switch to f. typica in the spring, in the field it may be less important than low temperatures.
Insect tracheal taenidia contain a keratin‐like protein*
Authors: BACCETTI B. , BURRINI A. G. , GABBIANI G. , LEONCINI P.
Published: March 2008

ABSTRACT. The presence in insect tracheal taenidia of a protein having an immunochemical determinant common to vertebrate keratins is suggested. Taenidia react positively with a specific anti keratin serum both at the fluorescent and electron microscope level. In tracheal preparations, immunoblotting shows specificity for three polypeptides having molecular weights ranging from 62 to 43 kd, two of them corresponding to prekeratins. In the region of taenidia reacting with the antisera, 7–8 nm thick filaments are present. The occurrence of a keratin‐like protein in insects, and the role played in the tracheal intima are discussed.
Pupal attendance in the crabhole mosquito Deinocerites cancer: the effects of pupal sex and age
Authors: CONNER W. E. , ITAGAKI H.
Published: March 2008

ABSTRACT. Pupal attendance by adult males of the crabhole mosquito, Deinocentes cancer Theobald, was videotaped in the laboratory. The relationship between pupal attendance time and the sex and age of the attended pupa was clarified by quantitative analysis of the videotapes. Male D. cancer distinguish between male and female pupae if the pupae are within approximately 14 h of eclosion and males spend significantly more time attending such female pupae. The attendance time of female but not of male pupae increased exponentially as they approached eclosion.
Changes in haemolymph octopamine levels associated with food deprivation in the locust, Schistocerca gregaria
Authors: DAVENPORT ANTHONY P. , EVANS PETER D.
Published: March 2008

ABSTRACT. Levels of octopamine in the haemolymph and locomotor activity have been measured over 24 h in fed and food‐deprived adult male locusts, Schistocerca gregaria (Forskål). Locusts are predominantly diurnal, the locomotor activity of individuals with continuous access to food was higher during the photophase. The basal level of octopamine in haemolymph sampled during the first quarter of the light cycle was 7.8±1.1 pg/μl (51 nm). Depriving locusts of food at the start of the photophase for 9 h caused an increase in both the speed of movement and total activity compared to fed individuals. There was a corresponding increase in the haemolymph octopamine concentration which continued for as long as the insects were unable to feed, reaching a concentration of 20.7 ± 3.7 pg/μl (135 nM). While declining, the levels of octopamine remained higher in fed locusts for up to 4 h after replacing the food. The results are discussed in relation to the regulation of feeding behaviour and a proposed neurohormonal role of octopamine in insects.
The periodicity of pheromone release and male responsiveness in the artichoke plume moth, Platyptilia carduidactyla
Authors: HAYNES K. F. , BIRCH M. C.
Published: March 2008

ABSTRACT. The periodicity of calling by female Platyptilia carduidactyla (Riley) is influenced by temperature and photoperiod. Both diurnal and nocturnal temperature changes shift the period of nocturnal calling, but in fundamentally different ways; lower daytime temperatures delay activity, while lower night temperatures result in earlier activity. Lengthening photoperiods result in activity earlier in the scotophase, but the period of activity does not maintain a constant phase relationship with either lights‐on or lights‐off. The periodicity of the behavioural response of males parallels that of calling by females, resulting in coordination of reproductive activities in the field. The result of these responses to environmental stimuli is that mating activity can occur throughout the year in coastal California.
The dynamics of height stabilization in Drosophila
Authors: DAVID C. T.
Published: March 2008

ABSTRACT. Frequency analysis of the height stabilizing system in Drosophila hydei Sturtevant was performed by moving a striped pattern sinusoidally up and down around free‐flying flies. The results show that height is controlled by the flies' vertical acceleration which is set linearly by the velocity of image movement past their eyes in the vertical direction, with a lag of 0.05 s at 25d̀C. No evidence was found of any reaction to the position of the striped pattern relative to the eyes. The gain of the vertical acceleration‐controlling reaction decreased with increasing frequency of visual stimulation. The dynamics of this decrease showed that it was not brought about by an integration step in the movement detector, but was due to the flies reaching the limit to the rate at which they could change their acceleration. The reaction time of the flies decreased with increasing temperature from 0.1 s at 15d̀C to 0.04 s at 30d̀C; the gain of the reaction increasing with temperature. When the vertical acceleration and the vertical velocity were determined every 0.02 s, the acceleration rather than the velocity was proportional to the flies' lift, and they took at least 0.3 s to reach their terminal velocity. This means that the acceleration‐controlling response found here is equivalent to the lift‐controlling responses of tethered flies.
Feeding responses of the horsefly, Tabanus nigrovittatus, to physical factors, ATP analogues and blood fractions
Authors: FRIEND W. G. , STOFFOLANO J. G.
Published: March 2008

ABSTRACT. Wild‐caught female horseflies, Tabanus nigrovittatus Macq. (Diptera: Tabanidae), were presented solutions of seven analogues of ATP in 0.15 m NaCl, or various blood fractions, either as free liquids at 22 or 38d̀C or covered with a Parafilm M membrane at 38d̀C. Warming the diet, so that it can stimulate the insects' heat receptors, or presenting it warmed and covered with a membrane, which the flies can pierce and thus deploy their mouthparts as they would when blood‐feeding, enhances the response to gorging stimulants. ADP (ED50 45 μM) was the most potent chemical phagostimulant. There were no significant differences between the potencies of AMP, A(TETRA)P, AMP‐PCP, AMP‐PNP or AMP‐S, which were 3.5‐5 times less potent than ADP. Cyclic AMP had no phagostimulatory activity at concentrations of 400 or 1000 μM. The ED50 for washed red blood cells (RBC) in saline was 4.5% (one tenth the concentration found in blood). RBC‐free plasma caused only 10% gorging but plasma with 0.5% RBC caused 61% gorging, indicating synergism between RBC and plasma.
Effect of plasma components on the feeding response of the mosquito Aedes aegypti L. to adenine nucleotides
Authors: GALUN RACHEL , OREN NAAMA , ZECHARIA M.
Published: March 2008

ABSTRACT. The gorging response of Aedes aegypti to the ATP dissolved in platelet‐poor plasma is greater than that of ATP dissolved in 0.15 m NaCl. The plasma components NaHCO3 and albumin account for the full effect of the potentiation. Phosphate or tris buffers do not duplicate the bicarbonate effect. In 0.15 m NaCl with bicarbonate but lacking albumin the concentrations inducing 50% feeding are 58 μM ATP, 140 μM ADP, 460 μM AMP and 1500 μM cAMP. Non‐adenine nucleotides such as ITP and GTP and phytic acid, and 2,3‐diphosphoglyceric acid had no activity.
Interactions between dietary nitrogen and simulated autumn conditions on diet consumption and reproductive development in the boll weevil, Anthonomus grandis
Authors: HILLIARD RICHARD A. , KEELEY LARRY L.
Published: March 2008

ABSTRACT. Dietary nitrogen content and short‐day, cool scotophase temperature were investigated for effects on diet consumption and reproductive development in the female boll weevil, Anthonomus grandis Boheman (Coleoptera: Curculionidae). Experimental weevils were maintained from the day of adult eclosion on cottonseed flour diets on a LD10:14 h, 27:15d̀C cycle. Control weevils were maintained under long‐day conditions (LD13:11) at a constant 27d̀C.

Diets containing 4% and 1.7% N were labelled with a 14C‐amino acid mixture and fed to individual females for 24 h to permit determinations of diet consumption rate, amino acid absorption, and reproductive allocation of the assimilated amino acids.

Females fed the 1.7% N diet under long‐day, 27d̀C laid 50% fewer eggs than females fed the 4% N diet under the same regimen. Egg production was depressed further by the 1.7% N diet when combined with short‐day, and cool scotophase temperatures. These latter conditions delayed, but did not prevent, attainment of a high rate of egg production by females fed the 4% N diet.

The short‐day, cool temperature regimen also stimulated diet consumption but reduced the allocation of absorbed 14C amino acids towards oogenesis.
Arrestment responses of the predatory mite, Phytoseiulus persimilis, to steep odour gradients of a kairomone
Authors: SABELIS M. W. , VERMAAT J. E. , GROENEVELD A.
Published: March 2008

ABSTRACT. The response of the predatory mite, Phytoseiulus persimilis Athias‐Henriot, to steep gradients of a volatile kairomone emitted by its prey, Tetranychus urticue Koch, was studied in a vertical air flow chamber. The orientation to wind direction was eliminated by using an olfactometer that had an air stream approaching the predator from below a gauze screen upon which the predator walked. The steep gradient of odour was obtained by putting a cylinder filled with prey‐infested leaves vertically below the screen. Starved predators were arrested in the odour patch by walking more slowly and tortuously than well‐fed predators. The latter mites did not show a significant ortho‐ or klinokinetic response to the presence of odour. Both well‐fed and starved predators showed a chemotactic response to steep gradients at the border of the circular odour patch. Predators that happened to walk out of the patch, frequently turned back to it. This response is presumably based on idiothetic information about the predator's immediately previous walking directions, because it occurred in the odour‐free zone after passing the steep gradient of prey odour. Right‐about turns can help the predator to stay in static odour plumes with steep gradients at the borders. This type of plume is present only close to the odour source. Further away from the source the odour plume tends to move to and fro due to variation in wind direction. For the predator to keep track of these snaking plumes the right‐about turns are unlikely to be of any value because the response is of short duration and because the response to a moving plume appeared to be inadequate; by moving the cylinder below the screen (and consequently the odour patch) it was found that the predator turned back even if the odour gradient was made to pass the predator in the same direction as that of the predator's movement.
Phonotaxis and aggression in the coneheaded katydid Neoconocephalus affinis
Authors: BRUSH JEFFREY S. , GIAN VICTOR G. , GREENFIELD MICHAEL D.
Published: March 2008

ABSTRACT. Positive phonotaxis to tape recorded conspecific song by males of the katydid Neoconocephalus affinis (Beauvois) (Orthoptera: Tettigoniidae) was studied in the field, in Puerto Rico. N.affinis males stridulated loudly during evening hours, and most males were territorial. Aggression between neighbours occurred, albeit rarely, and playback experiments using tape recordings of N.affinis song showed that aggressive behaviour, in the form of jumps directed toward a loudspeaker, could be elicited from a male by song broadcast above a threshold sound intensity. Response thresholds for different males varied from 76 to 93 dB, intensities that corresponded to calculated inter‐neighbour distances of 1.6‐0.26 m, respectively. Insects that had lower response thresholds were on average more isolated from neighbours and also stridulated more persistently and at a higher sound intensity than insects with higher response thresholds. N.affinis males displayed no phonotaxis toward the song of Neoconocephalus maxillosus, a sympatric species whose song is similar to that of N.affinis in principal frequency but differs in wingstroke rate. Phonotaxis toward conspecific song could only be elicited from males while they were silent.
Tethered flight of the potato moth, Phthorimaea operculella
Authors: FOLEY DESMOND H.
Published: March 2008

ABSTRACT. The effects of sex, age and mated state on average flight speed, duration and distance were determined for potato moths, Phthorimaea operculella (Zeller) (Lepidoptera, Gelechiidae), tethered to flight mills. Moths were classified as non‐fliers (NFs), good‐fliers (GFs) and remaining‐fliers (RFs) on the basis of their performance over the first two flights. Some moths flew for over 5 h non‐stop, while others tethered overnight flew between 20 and 30 km. Speed, duration and distance flown were greater during the first flight. First flight duration and distance flown by females decreased with age, whereas no trend was evident for males. Mated males and females flew slower first flights with increasing age, whereas virgin moths showed no marked trend. The analysis of fliers and NFs revealed that GFs were heavier than both RFs and NFs, GFs were faster than RFs, the percentage of NFs increased with age especially for mated females, and the percentage of GFs decreased with age. Age and mated state are important factors influencing flight performance especially for female moths. The relevance of these results to the field situation and the possible application of tethered flight to tests of potato moth quality are discussed.
The digestion of dandelion pollen by adult worker honeybees
Authors: PENG YING‐SHIN , NASR MEDHAT E. , MARSTON JERRY M. , FANG YUENZHEN
Published: March 2008

ABSTRACT.The digestion of dandelion (Taraxacum officinale) pollen by adult worker honeybees (Apis melliferaLinn.; Hymenoptera: Apidae) was initiated at the germination pores. 30 min after feeding, pollen had reached the anterior midgut and the germination pores had become swollen. This permitted further removal of protoplasm during the next 2 h of digestion as the pollen passed into the middle portion of the midgut. 3 h after feeding, pollen grains had reached the posterior midgut where some had ruptured to release both ‘naked’ protoplasm and masses of protoplasm but many remained intact or were only partially digested; undigested pollen grains passed unchanged to the rectum. The lipid‐rich pollenkitt layer was removed from the exine during digestion. Our studies indicate that dandelion pollen was not utilized completely by honeybees.
Trophallaxis by temporal subcastes in the fire ant, Solenopsis invicta, in response to honey
Authors: SORENSEN A. ANN , BUSCH TANA M. , VINSON S. BRADLEIGH
Published: March 2008

ABSTRACT. Trophallactic behaviour of temporal subcastes in Solenopsis invicta Buren colonies was studied in two separate experiments. First, radiolabeled honey was presented to small colonies containing larvae, queens and marked workers; radioactivity in the head, thorax and abdomen of each ant was measured after 0.25, 1, 6, 12, 24, 48 and 72 h. The quantity of honey per subcaste was dependent on the total amount of honey collected. As more honey entered the colony, the quantity in foragers, queens and reserves increased more rapidly than that in nurses or larvae. The internal distribution of radioactivity in the head, thorax or abdomen indicated that differences between subcaste members in either the rate of food exchange or digestion existed. In a second experiment behavioural observations were made on marked workers in colonies before and after the presentation of honey. Reserves spent significantly more time engaged in trophallaxis than either foragers or nurses, both as active donors and active receivers. Based on number of encounters, nurses were more likely to receive honey while reserves and foragers were more likely to donate honey. The duration of encounters involving nurses tended to be shorter than those involving reserves or foragers.
Effects of mating, nutritional condition, and mouthpart separation on ingestion and destination of sugar and water by the mosquito Culiseta inornata
Authors: FRIEND W. G.
Published: March 2008

ABSTRACT. ‘Hungry’ tethered female Culiseta inornata (Williston) (Diptera: Culicidae) with their mouthparts separated, respond in the sugar‐feeding mode when the fascicle is immersed in 1 M sucrose, and in the drinking mode when the fascicle is immersed in water. Similarly treated animals that are ‘not hungry’ respond in the drinking mode to water on the fascicle, but when given 1 M sucrose on the fascicle take less than a normal amount and tend to put it in the midgut instead of the crop. ‘Starving’ animals respond in the sugar‐feeding mode to sucrose on the fascicle, but when given water on the fascicle take slightly more than a normal amount, and about 50% put it in the crop. These results occurred whether the labellum was immersed in water, 1 M sucrose, or nothing. Differences in responses by tethered animals with separated mouthparts and non‐tethered intact animals can be attributed to mouthpart deployment. These results do not agree with those of other workers who report that similarly treated female C. inornata require stimulation of both the fascicle and labellar chemoreceptors before they will ingest. These differing results raise interesting questions concerning the range of feeding behaviours available to different demes of this mosquito, and indicate how these behaviours are modified by differences in pre‐test nutritional condition and mouthpart deployment.