Sensilla on the aedeagus of the ground beetle Carabus (Ohomopterus) arrowianus arrowianus (Breuning) (Coleoptera: Carabidae)

Sensilla on the aedeagus of the ground beetle Carabus (Ohomopterus) arrowianus arrowianus (Breuning) were investigated by scanning electron microscopy. On the aedeagus, a total of six types of sensillum were confirmed: five basiconic and one coeloconic. The external features and distributional patterns of the sensilla are described.     

Sensory organs inIps typographus (Insecta: Coleoptera) — Fine structure of antennal sensilla

Summary The antennal sensilla inI. typographus are almost exclusively confined to the flattened terminal flagellar segment. The sensillar types have distinct distribution patterns in the three areas where they are found. Judging from the ultrastructural characteristics the following functions can be assigned to the sensillar types: chemoreception, single-walled and double-walled sensilla; chemoreception/mechanoreception, terminal-pore sensillum. Moreover there are two types of mechanoreceptors, one of which is connected to a bristle, whereas the other terminates within the cuticle of the flagellar segment.This study was made within the Swedish project Odour Signals for Control of Pest Insects.     

Tri-trophic effects of transgenic insect-resistant tobacco expressing a protease inhibitor or a biotin-binding protein on adults of the predatory carabid beetle Ctenognathus novaezelandiae

Tri-trophic impacts on adult predatory carabid beetles, Ctenognathus novaezelandiae, of insect-resistant transgenic tobacco plants expressing a serine protease inhibitor, bovine spleen trypsin inhibitor (BSTI), or a biotin-binding protein, avidin, were investigated. Both proteins could potentially affect this beetle, since avidin is known to be insecticidal to many beetle species and C. novaezelandiae midguts were shown to contain high levels of trypsin, a protease powerfully inhibited by bovine pancreatic trypsin inhibitor (a BSTI homologue) in vitro. Newly emerged field-collected adult C. novaezelandiae were fed exclusively for 280 days on Spodoptera litura larvae raised either on non-transgenic control, transgenic avidin (55 ppm) or transgenic BSTI (68 ppm) tobacco. Despite this long-term exclusive diet, there was no treatment effect on survival or fecundity and only minor and transient effects on beetles were observed. Data pooled across time and genders showed control-prey-fed beetles weighed 3% more than BSTI-prey-fed beetles and avidin-prey-fed beetles consumed 3-4% fewer prey than control- or BSTI-prey-fed individuals. Females in all treatments gained more mass and survived longer than males. Low exposure to the proteins because of dilution and deactivation within the prey is the most likely explanation for the lack of tri-trophic effects observed. Aditionally, the presence of a digestive chymotrypsin only partially inhibited by BSTI may provide an alternative path for proteolysis.     

Morphometry and eye morphology in three species of Carabus (Coleoptera: Carabidae) in relation to habitat demands

Morphological features of three common European olfactory hunting carabid beetles, Carabus coriaceus mediterraneus Born, 1906, Carabus lefebvrei Dejean, 1826 and Carabus preslii neumeyeri Schaum, 1856, were compared. According to eye measurements, the three species are nocturnal and/or twilight hunters. They differ, however, in relative length of the antennae, relative surface area of the compound eyes, density of ommatidia and relative head width. These differences can be correlated with the species-specific habitat demands (light intensity, open land or shaded places). In particular, the greater lateral eye protrusion in C. lefebvrei corresponds to its tree-climbing habits, while the larger relative eye surface area and ommatidia density in C. coriaceus correspond to its choice of open habitats.     

Ultrastructure of the antennal sensilla of aphids

Summary An electron microscopical study was made of the coeloconic and placoid sensilla on the antennae of the aphids Aphis pomi, Macrosiphum euphorbiae, Nasonovia ribis-nigri, and Pemphigus bursarius. Scanning electron microscopy revealed some variation in morphology which may be functionally important but is more likely to reflect the evolution of these species.The placoid sensilla were shown by transmission electron microscopy to have the same basic structural pattern. Each group of two or three neurons is surrounded by two ensheathing cells. The ciliary regions of the dendrites pass through a vacuole into a cavity between an outer and an inner cuticle where they may be connected to the dendritic branches although such connections were not seen. Small pores (8 nm diameter) partially penetrate the cuticle implying that these sensilla have an olfactory function. They are suggested to be important in host selection by alate aphids.The coeloconic sensilla are poreless pegs with nonsensory cuticular projections at their tips. The distal portions of their dendrites contain densely packed microtubules and the cellular arrangement of the sensilla is similar to that of the placoid sensilla. It is suggested that they may function as thermoreceptors.The authors thank the Long Ashton Research Station, Bristol for use of the SEM facilities. A.K. Bromley gratefully acknowledges the tenure of a S.R.C. CASE Studentship and thanks Professor L.H. Finlayson for research facilities     

绿步甲的形态特征及其生物学特性

记述绿步甲Carabus(Coptolabrus)smaragdinus Fischervon Waldheim各虫态的形态特征及其生物学特性。在山东嘉祥,该虫1年发生2代,以成虫在土壤中越冬。成虫在4月至10月活动,分别与7月上旬、9月中旬产卵。卵期平均为8d;幼虫共2龄,历期分别为4d,13～15d;预蛹期约为15d;蛹期为7～8d。成、幼虫以蜗牛和多种鳞翅目昆虫为食。     

Ultrastructure of the antennal sensilla of aphids

Summary An electron microscopical study of aphid antennal sensilla has revealed two types of trichoid sensilla. Type I, innervated by a single neuron is mechanoreceptive; type II, innervated by three to five neurons is both mechanoreceptive and chemoreceptive with possibly a third function. Johnston's organ in the pedicel comprises a peripheral ring of scolopidia inserted into the joint with the flagellum; two non-peripheral groups of scolopidia lie in the lumen with attachment points in the wall of the third segment. The fine structure of a campaniform sensillum on the pedicel is described together with two homologous and previously unknown sense organs at the joint between the fifth and sixth antennal segments. An unusually placed scolopidium in the lumen of the sixth segment has also been found. The function of this scolopidium is unknown but Johnston's organ, the campaniform sensillum and joint receptors are suggested to act as antennal proprioceptors.The authors thank the Long Ashton Research Station, Bristol for use of the SEM facilities. A.K. Bromley gratefully acknowledges the tenure of a S.R.C. CASE Studentship and thanks Professor L.H. Finlayson for research facilities     

Sensory biology of Phalangida harvestmen (Arachnida,Opiliones): a review,with new morphological data on 18 species

Phalangida includes three of the four suborders of Opiliones (Arachnida): Eupnoi, Dyspnoi and Laniatores. We review the literature on the sensory structures and capabilities of Phalangida, provide new morphological data for 18 species and discuss the 11 sensory structures that have been described in the group. Based on the published data encompassing both behaviour and morphology, three conclusions are apparent: (1) species of Phalangida appear to have limited abilities to detect stimuli at a distance; (2) close range olfaction probably helps to find foods with strong odours, but (3) they appear to be highly dependent on contact chemoreception to detect live prey, predators and mates. We also highlight the fact that legs I in the three suborders and pedipalps in Dyspnoi and Eupnoi are very important sensory appendages, thus legs II should not be called the ‘sensory appendages’ of harvestmen. In conclusion, we highlight the fact that the sensory capabilities, diet, prey capturing and handling ability, and foraging behaviour of species of Phalangida seem to be different from those of most other arachnids. Finally, we suggest future directions for studies in the field of the sensory system of the group.     

北京东北旺农田景观步甲群落结构的时空动态比较

2000年5～10月在北京海淀区东北旺实验基地,采用陷阱法对林地、农田边界和农田3类生境共14个处理的步甲进行了取样。并在此基础上分析了不同生境和不同季节步甲科昆虫群落的动态分布特征。结果表明,林地和农田边界类生境相对于农田类生境拥有更多的步甲个体数和物种数;无论是优势种还是稀有种都趋向于在林地和边界处生活;边界对相邻农田步甲群落的多样性有积极影响;对边界进行适度的干扰(秋季翻耕)有利于提高步甲群落的个体数量;农田生境中灌溉、施肥和秸秆还田对农田中步甲群落的个体数量和物种数量的空间分布均无显著影响。此外,还结合步甲的时空分布特性对步甲受威胁状况进行了初步的分析。