The accessory salivary gland as the source of water in the saliva of hemiptera: Heteroptera

Summary Ablation of the accessory salivary glands of a pentatomid and of a coreid reduced quantitatively the flow of alkaline, watery saliva that can be induced by topical application of pilocarpine.     

Centromere nature of the chromosomes ofRanatra (Heteroptera)

Zusammenfassung Histologisch-cytologische Untersuchungen zeigen, dass die Chromosomen vonRanatra monozentrisch sind. Der Befund steht im Gegensatz zu Ergebnissen anderer Autoren an andern Heteroptera-Arten, die polyzentrische Chromosomen haben. Die Natur des Centromers ist also bei verschiedenen Arten der Heteropteren verschieden.     

Instar-specific defensive secretions of stink bugs (Heteroptera: Pentatomidae)

Defensive secretions (allomones) from first-instar nymphs of stink bugs in the subfamily Pentatominae contain (E)-4-oxo-2-decenal as a major constituent, whereas this compound is absent from later instars. In contrast, first instars ofEdessa meditabunda (Edessinae) produce allomones like those of later instars. The C₆ and C₈ (E)-4-oxo-2-alkenals are common, characteristic exocrine compounds of nymphal and adult Heteroptera, but (E)-4-oxo-2-decenal is previously unknown as a major natural product for which a biological role has yet to be established.     

Amino acid and allozyme frequency changes in overwinteringChymomyza amoena (Diptera: Drosophilidae) larvae

Summary Proline is accumulated by overwinteringC. amonea larvae. Mortality averages over 50% by spring. PGM^F in the population shifts from 70% in summer to less than 50% during winter, increasing again in summer. Product synthesis from stored glycogen may be mandated in dipteran larvae also using larval proteins for cold hardiness when completion of development is delayed until spring.Thanks are gratefully extended to Derek Lamport and Patrick Muldoon of the MSU/DOE Plant Biology Laboratory for the amino acid analyses. Thanks are also extended to Jerry Wolfe, Director of Mt. Lake Biological Station in summer, 1985 and Blaine Cole, Director beginning summer, 1986 for research space, to the University of Virginia, Charlottesville for a fellowship for the work at MLBS in summer, 1986 and to all the property owners in Michigan and Virginia who allowed collection at their orchards, farms, gardens or residences. Apples in January and March, 1986 were from a university research orchard. — This paper is dedicated to Hampton L. Carson on his retirement.     

Amino acid composition of crude and germinated guarseed flour protein (Cyamopsis Psoralioides)

Zusammenfassung Untersuchungen über die Aminosäurezusammensetzung des Mehles von ungekeimten und gekeimten Guarsamen (Cyamopsis Psoralioides), die ein billiges, hochproteinhaltiges Nahrungsmittel darstellen, haben ergeben, dass die Aminosäurekombination im gekeimten Samen einer guten Proteinqualität entspricht. Die Prüfungen über den biologischen Wert dieses Mehles sind im Gange.     

3-Methyl-2-hexanone from the triatomine bugDipetalogaster maximus (Uhler) (Heteroptera; Reduviidae)

Summary The occurrence of 3-methyl-2-hexanone as a major component of the secretion and possible alarm substance from the metasternal scent glands in the triatomine bugDipetalogaster maximus is reported.The authors are indebted to Mr B.O.C. Gardiner of the Zoology Department, Cambridge, for a supply of livingDipetalogaster. They would like also to thank Dr D.E. Games for the provision of mass spectral facilities under support from the S.E.R.C.     

Moult inhibition in the insectDysdercus cingulatus (Insecta: Heteroptera) by the cerebral glands of the millipedeJonespeltis splendidus (Myriapoda,Diplopoda)

Summary Implantation of 2 pairs of cerebral glands of the diplopodJonespeltis into the newly-moulted 4th or 5th instar nymphs of the insectDysdercus delayed the moulting of these insects for a fairly long time. Implantation of cerebral glands into 1-day old 5th instars postponed the subsequent moult for a shorter period, whereas implantation of cerebral glands into 2-day old 5th instars had no effect. These observations suggested that a neurosecretory factor from the cerebral glands inhibited moulting in this insect, and in the case of 5th instar nymphs there was a critical period before which implanted glands were effective in moult inhibition.Acknowledgments. Prof. V.K.K. Prabhu is thanked for suggesting the topic and for guidance. The University of Kerala is thanked for the fellowship awarded. The laboratory facilities afforded are also gratefully acknowledged.     

Photoperiodic summation is temperature-dependent inPyrrhocoris apterus (L.) (Heteroptera)

Summary InPyrrhocoris apterus, a low temperature, 15°C, prevented the termination of diapause by long days and, unexpectedly, also the induction of diapause by short days. Both responses were enabled at a higher temperature, 26°C. In contrast to current concepts, it was proved that the summation of photoperiodic signals was temperature-dependent, since the morphogenetic development was prevented by starvation.     

Pulse-train synchronous pair-stridulation by maleSigara striata (Heteroptera,Corixidae)

Summary Two by two, stridulating males ofSigara striata are able to synchronize the time structure of their calls (pulsetrain synchronous stridulation).Supported by Deutsche Forschungsgemeinschaft, SFB 4 Regensburg.     

Observations on the neurosecretory axons in the aortal wall ofHalys dentatus F. (Heteroptera: Pentatomidae)

Zusammenfassung Neurosekretorisches Material kann in der Wand der Aorta eines Insekts nachgewiesen werden. Das Material befindet sich dort ausschliesslich in den sich verzweigenden Axonen der NS-Zellen.     

Secretion of the metathoracic glands of the waterbugNotonecta glauca L. (Heteroptera; Notonectidae)

Zusammenfassung Im Geruchssekret der WasserwanzeNotonecta glauca L. wurdenp-Hydroxybenzaldehyd undp-Hydroxybenzoesäuremethylester eindeutig nachgewiesen. Daneben finden sich noch nicht identifizierte Stoffe ketonischer Natur.     

On the multiple sex-chromosome mechanism inTrapezonotus arenarius L. (Heteroptera,Lygaeidae)

Zusammenfassung Die charakteristische Grundzahl der Chromosomengarnitur beiTrapezonotus arenarius L. wurde mit 12A+2m+X+Y gefunden, wobei ein Individuum mit überzähligem Geschlechtschromosom festgestellt werden konnte.     

Sound communication inNezara viridula (L.) (Heteroptera: Pentatomidae): Further evidence that signal transmission is substrate-borne

We investigated the sound communication associated with mating inNezara viridula (L.) to clarify conflicting reports on the medium through which acoustic signals are borne. Recordings made from virgin pairs ofN. viridula during precopulatory and compulatory behaviour have revealed that signals transmitted as vibrations through the substrate are a more likely means of communication than signals transmitted by a radiation of sound pressure waves through the air (at least in Australian populations). We present evidence (additional to that already in the literature) that air-borne acoustics are an unlikely mechanism of sexual communication in this species. Specifically, the recorded pulse train patterns showed no consistency or repeatability in relation to different stages of mating behaviour. In contrast, frequency spectrograms of substrate-borne signals reveal repeatable patterns that do correspond with the stage of mating behaviour.     

Chromosome numbers in five species of pentatomidae reut (Hemiptera - Heteroptera)

Zusammenfassung Die 5 SchildwanzenartenCoptosoma scutellatum Geoffr.,Elasmucha grisea L.,Legnotus picipes Fall.,Phimodera lapponica Zett. undEurygaster testudinaria Geoffr. wurden während der Spermatogenese karyologisch geprüft. Mit Ausnahme vonLegnotus picipes Fall. wurde die diploide Chromosomenzahl mit 2M+8A+X+Y bestimmt.     

Composition and novel pattern of emission of defensive scent oils in the larva of the contton seed bugOxycarenus hyalinipennis (Costa) (Heteroptera: Lygaeidae)

Summary differences in composition and pattern of eiission in the scent oils from the two abdominal scent glands in the larva ofOxycarenus hyalinipennis are reported. The scent oils contain hex-2-enal, oct-2-enal, dec-2-enal and 4-oxo-oct-2-enal.We thank D. E. Games for access to mass spectral facilities, M. Rossiter for recording the mass spectra, the Bayero University Higher Degrees Committee for providing funds to T. O. Olagbemiro and PPF International for supply of sample materials.     

Dilation of nervi corporis allati 2 (NCA 2) — a neurohaemal structure inChrysocoris stolli wolf. (Heteroptera: Pentatomidae)

Summary The NCA 2 is dilated in about the middle of its length. Neurosecretory material is stored in this dilation. It serves as a secondary neurohaemal organ for lateral neurosecretion.     

Effect of temperature on the neurosecretory activity inNezara viridula Linn. (Heteroptera; pentatomidae)

Zusammenfassung Die neurosekretorischen Zellen und die davon ausgehenden Nerven vonNezara viridula Linn enthalten bei Zucht in niedriger Temperatur bedeutend weniger Neurosekret als in Normaltemperatur.