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The influence of thermal acclimation on the amylolytic activity and microanatomy of the alimentary tract of the oribatid mite Galumna elimata (Acari: Oribatei)SUSTR V., HUBERT J.Eur. J. Entomol. 96 (2): 189-198, 1999 The oribatid mite Galumna elimata was reared under laboratory conditions on algae (Protacoccus spp.) at different temperatures (5, 15 and 20°C). Higher weight-specific amylolytic activity was found in the whole body homogenates of mites exposed to cold acclimation (5°C, 21 days) in comparison with individuals acclimated to 15 and 20°C. Accompanying parameters (live body weight, content of total soluble proteins in the body, protein-specific amylolytic activity, presence and composition of food boluses, activity of mesenteric and caecal wall cells, gregarinid parasitisation, number of glycogen granulae and guanine deposits in mesenchymal tissue, presence of proventricular glands) were investigated at all three acclimation temperatures to explain mechanisms of this change. The acclimation response of weight-specific amylolytic activity was accompanied by elevation of protein-specific amy lolytic activity. Microanatomical features did not confirm any increased secretion activity of mesenteric and caecal cells in cold acclimated animals. Granulation and apocrine secretion of these cells increased with increasing temperature as with food ingestion. The food boluses contained algae or algae mixed with unknown fungal hyphae in individuals acclimated to 15 and 20°C. The concentrated mucoid substances prevailed in animals exposed to cold, indicating lower feeding activity at 5°C. Based on these findigs, Lye hypothesised that specific amylolytic activity reflected passively the different changes in protein composition of the body at different temperatures and its elevation is without direct adaptive importance. |
Temperature and development of central European species of Amara (Coleoptera: Carabidae)Pavel SASKA, Alois HONĚKEur. J. Entomol. 100 (4): 509-515, 2003 | DOI: 10.14411/eje.2003.078 Development rates of the eggs of 9 species, larvae of 6 species and pupae of 6 species of the genus Amara (Coleoptera: Carabidae) were recorded at five constant temperatures between 17 and 28°C, and thermal constants for each development stage calculated. The lower development threshold varied between 9.2-13.5°C for different stages and species. Rate isomorphy, which implies the existence of a common temperature threshold for all development stages, was demonstrated in 5 species. The sum of effective temperatures differed between stages. On average the egg stage took 18%, the first larval instar 13%, second instar 13%, third instar 35% and pupa 21% of the total development time. A poor diet increased the SET of the larvae. The results are compared with published data on Carabidae. |
Habitat of pre-hibernating larvae of the endangered butterfly Euphydryas aurinia (Lepidoptera: Nymphalidae): What can be learned from vegetation composition and architecture?Martin KONVICKA, Vladimir HULA, Zdenek FRICEur. J. Entomol. 100 (3): 313-322, 2003 | DOI: 10.14411/eje.2003.050 Habitats of pre-hibernating gregarious larvae of the endangered Marsh Fritillary butterfly (Euphydryas aurinia) were studied in field in Western Bohemia, Czech Republic. The species inhabits moist seminatural meadows managed by light grazing and haymaking; the only local host plant is Succisa pratensis. The redundancy analyses of the vegetation composition (around 166 nest-bearing and 381 unoccupied host plants) showed that nest presence was positively associated with short cushion-forming grasses (esp. Nardus stricta). It was negatively associated with competitively superior tall grasses (e.g., Deschampsia caespitosa) and tall herbs. Comparison of Ellenberg's indicator values of vegetation in occupied vs. unoccupied plots revealed that the nests were more often found in drier, nitrogen-poorer and more acidic conditions than unoccupied plants. Multiple regressions of nest presence against architecture of the host plants (170 occupied, 1280 unoccupied) revealed that the nests were associated with densely clumped host plants, low to medium height of sward and mechanical disturbance. The patterns agree with our knowledge of the biology of the larvae: short sward (related to low nitrogen, humidity, and low pH) facilitates larval basking; high host density reduces the likelihood of starvation. Sod disturbance facilitates host plant germination. The conditions favourable for the nests were also favourable for the host plant, but the plants grew in broader range of conditions than that occupied by the nests. The abandoning of a site results into a situation when the conditions first become intolerable for the butterfly, and ultimately for the plant. Since grazing and mowing have a different impact on vegetation composition and architecture, we propose that the studied populations have persisted in a semi-dynamic state in the two modes of management. Conservation management should mimic the dynamics of traditional land use on the smaller scales of extant colonies. |
Revision and phylogenetic analysis of the subfamily Platerodinae (Coleoptera: Lycidae)Milada BOCÁKOVÁEur. J. Entomol. 98 (1): 53-85, 2001 | DOI: 10.14411/eje.2001.010 Genus-group taxa of Platerodinae are revised and valid taxa are redescribed. The validity of Plateros Bourgeois, 1879 is reinstated. Libnetomimus Kleine, 1927 is made a junior synonym of Libnetis Waterhouse, 1878. Calleros Gorham, 1881, Calloplateros Pic, 1923, Costatoplateros Pic, 1949, Ditoneces Waterhouse, 1879, Libnetomorphus Pic, 1921, Microplateros Pic, 1921, Planeteros Gorham, 1883, Tolianus Pic, 1921, Melampyrus Waterhouse, 1879, and the subgenus Cautirodes Pic, 1921 are considered to be junior synonyms of Plateros Bourgeois, 1879. The subgenus Pseudeuplectus Pic, 1922 is synonymized to Cavoplateros Pic, 1913, and Pseudoplateros Green, 1951 is made a junior synonym of Falsocalleros Pic, 1933. Macrolibnetis Pic, 1938 formerly classified with Platerodini is synonymized to Platerodrilus Pic, 1921. Samoaneros Blair, 1928 is considered to be a junior objective synonym of Melaneros Fairmaire, 1877, which is excluded from Platerodinae and is kept incertae sedis in Lycidae. Fernandum Pic, 1924 and Subdihammatus Kleine, 1926 are transferred to the subfamily Leptolycinae. Teroplas oculatus sp. n. and Microlycus mexicanus sp. n. are described. Neotype of Plateros brasiliensis (Lucas, 1857) and lectotype of Microlycus minutus Pic, 1922 are designated. In order to understand relationships within the subfamily, included genus-group taxa were cladistically analysed. |
Effects of low temperature on the condition of flight muscles and flight propensity in a water strider, Aquarius paludum (Heteroptera: Gerridae)Tetsuo HARADA, Shizuna INOUE, Masao WATANABEEur. J. Entomol. 100 (4): 481-484, 2003 | DOI: 10.14411/eje.2003.073 Effects of chilling on dispersal characteristics of adults of the water strider, Aquarius paludum were studied in the laboratory. The condition of flight muscles was monitored during overwintering under natural conditions in Kochi (33°N), Japan. For diapause adults kept under 12h light-12h dark (12L : 12D), chilling at 7°C for 48h from the 70th day after emergence caused lower Supercooling Point (SCP) and promoted higher flight propensity than among gerrids not exposed to chilling. For reproductive adults kept under 15.5L : 8.5D, 91.3% of 34 adults retained well-developed flight muscles 1 week after the chilling (49 days after emergence), whereas 67.6% of 49 adults which had not been exposed to 7°C histolysed their flight muscles. According to diapause development, part of the adults which had well developed flight muscles histolysed them during December to February. Chilling in fall might trigger dispersal to overwintering sites by diapause adults and, that in spring could inhibit histolysis of flight muscles by overwintered reproductive adults. |
Descriptions of adults, immature stages and venom apparatus of two new species of Dacnusini: Chorebus pseudoasphodeli sp. n., parasitic on Phytomyza chaerophili Kaltenbach and C. pseudoasramenes sp. n., parasitic on Cerodontha phragmitophila Hering (Hymenoptera: Braconidae: Alysiinae; Diptera: Agromyzidae)Josep TORMOS, Xavier PARDO, Ricardo JIMÉNEZ, Josep Daniel ASÍS, Severiano F. GAYUBOEur. J. Entomol. 100 (3): 393-400, 2003 | DOI: 10.14411/eje.2003.061 The imagines, cast skin of the final larval instar, and venom apparatus of Chorebus pseudoasphodeli sp. n., an endoparasitoid of Phytomyza chaerophylli Kaltenbach, 1856 on Daucus carota L., and Chorebus pseudoasramenes sp. n., an endoparasitoid of Cerodontha phragmitophila Hering, 1935 on Arundo donax L., two new species of Dacnusini from Spain, are described, illustrated, and compared with those of allied species. The immature larvae, mature larva, and pupa of C. pseudoasphodeli sp. n. are also described, illustrated, and compared. Morphological structures of phylogenetic value are discussed, and keys for the discrimination of the imagines are provided. |
Immunohistochemical localization of clock proteins (DBT and PER), and [His7]- and [Arg7]-corazonins in the cerebral ganglia of Bombyx mori: Are corazonins downstream regulators of circadian clocks?Shao QI-MIAO, Seiji TANAKA, Makio TAKEDAEur. J. Entomol. 100 (2): 283-286, 2003 | DOI: 10.14411/eje.2003.044 The brain and subesophageal ganglion (BR-SG) of the commercial silk worm, Bombyx mori, were stained immunohistochemically at the larval stage for circadian clock neurons with antibodies against Doubletime (DBT) of B. mori and Period (PER) of Periplaneta americana. The BR-SGs were also stained with antisera against [Arg7]-corazonin, which has been known to be present in B. mori and co-localized with PER in Manduca sexta, and against [His7]-corazonin, a homolog identified in other species. From co-localization of [Arg7]-corazonin and PER-like reactivities in the pars lateralis, [Arg7]-corazonin is suspected to be a downstream regulator of the circadian clock in M. sexta. DBT- and corazonin-like immunohistochemical reactivities were found in both the neurosecretory cells of the pars intercerebralis (PIC) and pars lateralis (PL) in B. mori. Small numbers of neurons shared both reactivities against anti-DBT and anti-corazonin. The majority of the immunopositive cells were common to both corazonins, but some cells were unique in expressing either reactivity against [His7]-corazonin or [Arg7]-corazonin only. The results suggest that there is a diversity in the clock output pathway among lepidopterans and that [His7]-corazonin may be present in B. mori, as well as [Arg7]-corazonin, although the former has not been chemically identified in this species. Corazonin may be a downstream regulator of circadian clocks in B. mori because of the co-localization of [His7]-corazonin at PIC and [Arg7]-corazonin at PL with anti-DBT. |
Species at the edge of their range: The significance of the thermal environment for the distribution of congeneric Craspedolepta species (Sternorrhyncha: Psylloidea) living on Chamerion angustifolium (Onagraceae)BIRD J.M., HODKINSON I.D.Eur. J. Entomol. 96 (2): 103-109, 1999 There is much current discussion about the factors that control the distribution and abundance of animal species, particularly at the edges of their range. The significance of temperature for survival and development is compared in two closely related psyllid species (Craspedolepta nebulosa and C. subpunctata) living on the same host plant (Chamerion angustifolium) (Onagraceae) but displaying different distributions along latitudinal and altitudinal gradients. The following measurements were made at critical periods during the life cycle (a) winter supercooling points (SCPs), (b) tolerance of short (1 min) and long term (1-25) days exposure to sub-zero temperatures above the SCP, (c) tolerance of short term exposure to high spring/summer temperatures and (d) comparative field development rates among species and sites during the early critical part of the growing season. Successful completion of the life cycle is related to heat availability during the growing season. This appears to limit the distribution of the Craspedolepta species, rather than their survival response to thermal extremes. No significant differences were found between the two species in the supercooling point or in their long and short term survival responses at low or high temperatures. |
Mouthparts, gut contents, and retreat-construction by the wood-dwelling larvae of Lype phaeopa (Trichoptera: Psychomyiidae)Bernd SPÄNHOFF, Ulf SCHULTE, Christian ALECKE, Norbert KASCHEK, Elisabeth Irmgard MEYEREur. J. Entomol. 100 (4): 563-570, 2003 | DOI: 10.14411/eje.2003.085 The larvae of Lype phaeopa (Stephens, 1836) are found on dead wood substrates in streams and lakes. Gut content analyses, scanning electron microscopy of larval mouthparts, and gallery structure revealed characteristics of this habitat preference. The guts of the larvae contained mainly wood fragments whereas other food items (detritus, algae, fungi, inorganic particles) were much rarer. The suitability of the mouthparts to scrape wood surfaces, and the adaptative elongation of the silk-secreting spinneret, which facilitates the construction of retreats consisting of a tunnel-like silken net incorporating mainly wood fragments, are discussed. Retreat-construction under laboratory conditions indicated that larvae exploit new feeding areas by steadily extending their galleries. Tips of the maxillary palps bear five sensilla styloconica and five sensilla basiconica, almost all bearing an apical pore. Three sensilla styloconica, two with an apical peg, and two small inconspicious sensilla basiconica are located on the galea. Possible function of these sensilla is discussed on the basis of studies on the closely related sister-group of Lepidoptera. |
Enhanced expression of genes in the brains of larvae of Mamestra brassicae (Lepidoptera: Noctuidae) exposed to short daylength or fed DopaMasahide URYU, Yohsuke NINOMIYA, Takeshi YOKOI, Seiji TSUZUKI, Yoichi HAYAKAWAEur. J. Entomol. 100 (2): 245-250, 2003 | DOI: 10.14411/eje.2003.039 The cabbage armyworm, Mamestra brassicae, enters diapause in the early pupal stage. Pupal diapause is induced by rearing the larvae under short day lengths. We previously demonstrated that feeding Dopa during last larval instar induces pupal diapause even under long day lengths. In order to elucidate the mechanism by which pupal diapause is induced after experiencing short day lengths or fed Dopa under long day lengths, we analyzed gene expression in the brain of M. brassicae larvae under both of these conditions using a subtractive hybridization technique. After the secondary screen, 49 clones and 28 clones were identified as short day length or Dopa-feeding specific clones, respectively. All of these genes were sequenced and, using the base sequences of these clones, primers were synthesized. To confirm the genes enhanced specifically by these conditions, quantitative real-time PCR was carried out. This quantitative PCR analysis identified 15 and 1 clone whose expression was enhanced by the short day length conditions or Dopa-feeding, respectively. Among these clones, the gene with a high level of identity to receptor for activated protein kinase C (RACK) from Heliothis virescens is the most dramatically up-regulated under both conditions. |
Biology and immature stages of the clam-killing fly, Renocera pallida (Diptera: Sciomyzidae)Jana HORSÁKOVÁEur. J. Entomol. 100 (1): 143-151, 2003 | DOI: 10.14411/eje.2003.024 The larva of the Palaearctic Renocera pallida (Fallén, 1820) is confirmed as a predator of small species of bivalve molluscs of the family Sphaeriidae. To date only the larvae of three Nearctic Renocera species (and larvae of two other species of Sciomyzidae in two genera) are known to have the same food preference. The life cycle, biology, larval feeding and behaviour are described for the first time and compared with that of the Nearctic Renocera. The systematic position and biology of Renocera in general are discussed. Descriptions of the egg, second and third larval instars and the puparium of R. pallida are presented, the main features of the egg and larvae are illustrated by scanning electron micrographs. |
A review of the European planthopper genus Trirhacus and related taxa, with a key to the genera of European Cixiidae (Hemiptera: Fulgoromorpha)Werner E. HOLZINGEREur. J. Entomol. 99 (3): 373-398, 2002 | DOI: 10.14411/eje.2002.048 Ten species of Cixiidae, formerly placed in Trirhacus Fieber, 1875, are redescribed and one additional species is described. They belong to seven genera: Trirhacus s. str. with T. setulosus Fieber, 1876 (type species), T. dubiosus Wagner, 1959, T. biokovensis Dlabola, 1971 and T. peloponnesiacus sp. n., Apartus gen. n. with A. michalki (Wagner, 1948) comb. n. (type species) and A. wagnerianus (Nast, 1965) comb. n., Nanocixius Wagner, 1939 stat. n. with N. discrepans (Fieber, 1876) comb. n., Neocixius Wagner, 1939 stat. n. with N. limbatus (Signoret, 1862) comb. n., Sardocixius gen. n. with S. formosissimus (Costa, 1883) comb. n., Simplicixius gen. n. with S. trichophorus (Melichar, 1914) comb. n. and Sphaerocixius Wagner, 1939 stat. n. with S. globuliferus (Wagner, 1939) comb. n. The phylogenetic relationships of these genera to other Cixiidae are briefly discussed and a key to the genera of European Cixiidae is provided. |
Nymphal and adult cephalic chaetotaxy of the Cydnidae (Hemiptera: Heteroptera), and its adaptive, taxonomic and phylogenetic significanceJerzy A. LIS, Dominique PLUOT-SIGWALTEur. J. Entomol. 99 (1): 99-109, 2002 | DOI: 10.14411/eje.2002.017 Cephalic chaetotaxy of nymphal and adult stages of species from all the subfamilies of Cydnidae s. str. (sensu Froeschner, 1960 and Lis, 1994), namely Garsauriinae, Cephalocteinae, Cydninae, Sehirinae, and Amnestinae, was studied. Two types of setae, primary and secondary, are described, and changes they undergo during ontogeny reviewed. The adaptive, taxonomic and phylogenetic significance of the cephalic setae in the Cydnidae s. str. is discussed. A ground-plan of the original cephalic chaetotaxy of the family, and its evolution within the family Cydnidae s. str. are proposed. |
Effects of different atmospheric CO2 concentrations and soil moistures on the populations of bird cherry-oat aphid (Rhopalosiphum padi) feeding on spring wheatJun ZHANG, Geng-Mei XING, Jian-Xiong LIAO, Zong-Dong HOU, Gen-Xuan WANG, Ya-Fu WANGEur. J. Entomol. 100 (4): 521-530, 2003 | DOI: 10.14411/eje.2003.080 Spring wheat plants were grown in pots at three CO2 concentrations (350, 550 and 700 ppm) and three soil water levels (40, 60 and 80% of field water capacity) in field open top chambers and were infested with bird cherry-oat aphids (Rhopalosiphum padi Linnaeus). Aphid population dynamics were recorded throughout the growing season and analysis of the chemical composition of spring wheat leaves was conducted at the same time. Results showed that: (1) Aphid populations increased with raised atmospheric CO2 concentrations. (2) The aphid populations showed different responses to different CO2 concentrations. The population size, population growth rate and population density found under the 350 ppm CO2 treatment was far less than those recorded under the 550 and 700 ppm CO2 treatments. The population size, population growth rate and population density recorded under the 700 ppm CO2 treatment was slightly higher than those recorded under the 550 ppm CO2 treatment. (3) The effect of CO2 concentration on the aphid population was correlated with soil water level. The highest aphid population size was achieved under the 60% soil water treatment. (4) Atmospheric CO2 and soil moisture had significant effects on the chemical composition of the wheat leaves. (5) Aphid population size correlated positively with the concentration of leaf water content, soluble proteins, soluble carbohydrates and starch, while correlating negatively with the concentration of DIMBOA and tannin. |
Effects of temperature and genetic stress on life history and fluctuating wing asymmetry in Culex pipiens mosquitoesMandla MPHO, Amanda CALLAGHAN, Graham J. HOLLOWAYEur. J. Entomol. 99 (4): 405-412, 2002 | DOI: 10.14411/eje.2002.050 Fluctuating asymmetry (FA) of bilaterally symmetrical organisms has been introduced as a promising indicator of environmental stress. Stress factors reported to contribute to developmental stability include inbreeding and the presence of resistance genes. In the current study we examined the effect of stress derived from high developmental temperatures, resistance genes and low genetic variation on life history variables and wing FA in Culex pipiens mosquitoes. Three strains were compared: two inbred laboratory strains sharing a similar genetic background but differing in that one strain contained organophosphate (OP) resistance genes, and a third strain that was an outbred OP resistant field strain recently collected from India. There were no strong and general trends that suggested that the OP resistant lab strain was less fit than the OP susceptible strain, although there were some specific among strain differences for some treatments. Fluctuating asymmetry (FA) of wing traits was higher in the laboratory strains than the field strain, suggesting that inbreeding may cause elevated FA in the study species. There was no evidence that the resistance genes were associated with increased wing FA. Wing FA increased with increasing developmental temperature in females, but the association was less strong in males. There was a significant difference between the sexes in this respect. The results are discussed with reference to the value of FA as a biomonitor of environmental stress. |
Generic revision and phylogenetic analysis of the Metriorrhynchinae (Coleoptera: Lycidae)Ladislav BOCAKEur. J. Entomol. 99 (3): 315-351, 2002 | DOI: 10.14411/eje.2002.043 The subfamily Metriorrhynchinae is the most species-rich clade of Lycidae (Coleoptera). A recent proposal suggests that the Erotinae is a sister group of the Metriorrhynchinae. Within the Metriorrhynchinae, evidence is presented for the monophyly of the Conderini and Metriorrhynchini and their sister group position. The Trichalina, Hemiconderina and Metriorrhynchina form the tribe Metriorrhynchini. The relationships between the basal lineages of this group are poorly understood. Several clades are distinguished within the Metriorrhynchina, but there is only weak evidence supporting a relationships between them. The distribution of individual clades is discussed. Carathrix Kleine, 1926 (= Pseudodontocerus Pic, 1921), Dilolycus Kleine, 1926 (= Metriorrhynchus Gemminger et Harold, 1869), Flabelloporrostoma Pic, 1923 (= Metriorrhynchus Gemminger et Harold, 1869), Rossioptera Kasantsev, 1988 (= Xylobanellus Kleine, 1930), Samanga Pic, 1921 (= Broxylus C.O. Waterhouse, 1879), Strophicus C. O. Waterhouse, 1879 (= Enylus C.O. Waterhouse, 1879), and Tapromenoeus Bocak et Bocakova, 1989 (= Prometanoeus Kleine, 1925) are proposed as junior synonyms. Pseudosynchonnus Pic, 1922 is transferred to the Erotinae (Taphini) and Pseudosynchonnus Pic, 1922, Protaphes Kleine, 1926, and Parapyropterus Kleine, 1926 are proposed to be junior subjective synonyms of Lycoprogenthes Pic, 1915. Redescriptions of Metriorrhynchinae genera and a key to genera are provided. |
Photoperiodic clock of diapause termination in Pseudopidorus fasciata (Lepidoptera: Zygaenidae)Aiqing LI, Fangsen XUE, Ai HUA, Jianjun TANGEur. J. Entomol. 100 (2): 287-293, 2003 | DOI: 10.14411/eje.2003.045 Photoperiodic control of diapause termination was systematically investigated in Pseudopidorus fasciata. In 24 h light-dark cycles, the rate of diapause termination in this species depended on photoperiod. The critical night length (CNL) for diapause termination was 10 h, 0.5 h shorter than that for diapause induction. Night-interruption experiments with T = 24 showed that diapause was effectively terminated when the scotophases separated by light pulse were shorter than the critical night length (10 h); no developing individuals were found if the duration of the pre-interruption scotophase or the post-interruption scotophase exceeded the CNL. A 15-min light pulse was sufficient to reverse the effect of long night when it was placed 8 h after lights-off. Resonance experiments with a constant photophase of 12 h or 16 h and various scotophases of 4-80 h showed an hourglass-type photoperiodic response, where no rhythmicity was found. In another resonance experiment with constant scotophase of 8 h and various photophases of 4-72 h, all individuals developed into cocoons. In the Bünsow experiment, the response curve showed two apparent peaks for diapause termination, one being 8 h after lights-off, and another 8 h before lights-on. However, there was no periodic rhythmicity, which again indicates an hourglass principle. The results lead to the conclusion that the same photoperiodic clock mechanism (a long-night measuring hourglass) is involved in both diapause induction and termination. |
Pedicellar structures in Reduviidae (Heteroptera) - comments on cave organ and trichobothriaChristiane WEIRAUCHEur. J. Entomol. 100 (4): 571-580, 2003 | DOI: 10.14411/eje.2003.086 Sensillar structures of the antennal pedicel are investigated in Reduviidae and Pachynomidae. The cave organ, a presumably chemoreceptive structure, previously reported only for haematophagous Triatominae, is described here also for representatives of Peiratinae, Reduviinae and Stenopodainae. The systematic implication of the occurrence of this sensillar structure is discussed. Further, four sclerites located in the membrane between pedicel and preflagelloid are described and used as landmarks for the recognition of individual trichobothria in Reduviidae and Pachynomidae. Characters of the trichobothrial socket are studied and discussed systematically. Homology of the distalmost trichobothrium of Reduviidae with the single trichobothrium in Pachynomidae is proposed. This hypothesis is based on the structure of the cuticle surrounding the trichobothria and on the trichobothrial position relative to the four sclerites of the pedicello-flagellar articulation. The single trichobothrium present in most nymphs corresponds to the distalmost trichobothrium in adult Reduviidae in position and structural detail. A reasonable hypotheses on the homology of individual trichobothria of the proximal row or field seen in most Reduviidae can so far only be formulated for Peiratinae. |
Larval omnivory in Amara aenea (Coleoptera: Carabidae)Karel HŮRKA, Vojtěch JAROŠÍKEur. J. Entomol. 100 (3): 329-335, 2003 | DOI: 10.14411/eje.2003.052 The duration of development, survivorship and adult size were compared for the larvae of Amara aenea reared in the first generation on pure diets of seeds (Stellaria media, Capsella bursa-pastoris, Tussilago farfara, Plantago major, Urtica dioica, or Potentilla argentela), or a pure diet of yellow mealworms (Tenebrio molitor larvae), and on a mixed diet of seeds and mealworm larvae (T. molitor, S. media and C. bursa-pastoris). To ascertain any long-term effects of pure diets, the beetles were reared on the same pure diet for several generations, or on different pure diets in different generations. The hypothesis that the larvae are primary omnivorous was tested. The evidence that the larvae of A. aenea are primary omnivorous was obtained by revealing that the larvae reared on the mixed diet of insects and seeds survived better, and developed faster in larger adults than those reared on the pure diets of seeds or insects. When the beetles were reared on the same pure diet for several generations, survivorship, and in most cases also the duration of development, did not change. However, when the beetles were reared on a different pure diet each generation, survivorship significantly decreased in successive generations. |
Presence of [His7]- corazonin in the central nervous system of a newly isolated albino strain of Schistocerca gregaria (Orthoptera: Acrididae) - mass spectrometric and immunocytochemical evidenceMazibur M. RAHMAN, Geert BAGGERMAN, Liliane SCHOOFS, Arnold DE LOOF, Michael BREUEREur. J. Entomol. 100 (3): 455-458, 2003 | DOI: 10.14411/eje.2003.068 An inbred strain of a newly isolated spontaneous albino mutant of Schistocerca gregaria (Forsk.) was examined for the presence of the neuropeptide [His7]-corazonin by immunocytochemical and mass spectrometric methods. It was concluded that this peptide is definitely present in a limited number of neurosecretory cells in the pars lateralis as well as in the corpora cardiaca (CC). Injection of either synthetic [His7]-corazonin or of extracts of CC of the normal coloured phenotype of S. gregaria failed to induce darkening of the cuticle, while albino Locusta migratoria, used as a positive control, turned dark. The conclusion is that the cause of albinism in the new S. gregaria albino is probably due to a defect in the receptor system for [His7]-corazonin or in the biosynthetic pathway of melanin. |
Adaptive preferential selection of female coccinellid hosts by the parasitoid wasp Dinocampus coccinellae (Hymenoptera: Braconidae)Dexter S. DAVIS, Sarah L. STEWART, Andrea MANICA, Michael E.N. MAJERUSEur. J. Entomol. 103 (1): 41-45, 2006 | DOI: 10.14411/eje.2006.006 Females of the parasitoid wasp Dinocampus coccinellae are known to parasitise both male and female coccinellid hosts. It is suggested that female hosts provide more resources for developing wasp larvae because they tend to be larger than male hosts, and female coccinellids have a much greater food intake than males. Thus the wasp's lifetime reproductive success should be increased by ovipositing preferentially in female rather than male hosts when given a choice. Laboratory experiments, using Coccinella septempunctata as a host, show that such a preference does exist. Wasps preferentially oviposit in females, and this preference is not simply a result of the larger mean size of females compared to males. These results corroborate higher rates of prevalence in female compared to male hosts reported previously. |
Females of the specialist butterfly Euphydryas aurinia (Lepidoptera: Nymphalinae: Melitaeini) select the greenest leaves of Lonicera implexa (Caprifoliaceae) for ovipositionConstantí STEFANESCU, Josep PEÑUELAS, Jordi SARDANS, Iolanda FILELLAEur. J. Entomol. 103 (3): 569-574, 2006 | DOI: 10.14411/eje.2006.077 In Mediterranean habitats, the specialist butterfly Euphydryas aurinia oviposits on Lonicera implexa. Previous work has shown that ovipositing females select and lay a higher number of egg clusters on certain plants. In this paper the results of a field study aimed at assessing whether females use plant size and/or plant or leaf greenness (i.e., chlorophyll concentrations) as cues for oviposition are described. Size of plants did not appear to be an important factor in determining host plant selection, probably because even small plants provide enough resources for the young larvae to reach the diapausing stage and because last instar larvae, the most likely to face resource depletion, can move great distances in search of food. Measurements of both spectral reflectance and chlorophyll concentration of plants failed to reveal differences between host and non-host plants. On the other hand, reflectance and chlorophyll concentration of leaves were found to be important in oviposition choice as egg clusters were generally located on the greenest leaves with the highest chlorophyll contents. This suggests that females use visual cues to select the leaves that will provide optimal growth opportunities for newly hatched larvae. Although there was some indication that plants receiving a greater number of egg clusters also had more leaves of high chlorophyll content, multiple egg batches on single plants could also be a consequence of females being attracted by the presence of conspecific egg clusters. |
Diapause development and cold hardiness of Pectinophora gossypiella (Lepidoptera: Gelechiidae) larvae in GreeceOlga P. KALTSA, Panagiotis G. MILONAS, Matilda SAVOPOULOU-SOULTANIEur. J. Entomol. 103 (3): 541-545, 2006 | DOI: 10.14411/eje.2006.072 Larval diapause development and termination and some characteristics of cold hardiness in Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae) were studied under field conditions in northern Greece. P. gossypiella overwintering larvae were sampled at 20 to 30 day intervals and subjected to two photoperiodic regimes at 20°C. In larvae kept under a long-day photoperiod (16L : 8D) diapause development was accelerated compared to those kept under a short-day photoperiod (8L : 16D). There was no difference in response to the two photoperiods after February. Mean number of days to pupation of P. gossypiella overwintering larvae decreased progressively through the sampling period, from November to April. Chilling is not a prerequisite but does accelerate diapause development. Supercooling points for P. gossypiella overwintering larvae ranged from -14 to -17°C with the majority dying after freezing. |
Diagnostic molecular markers and the genetic relationships among three species of the Cheilosia canicularis group (Diptera: Syrphidae)Vesna MILANKOV, Jelena STAMENKOVIĆ, Jasmina LUDOŠKI, Gunilla STÅHLS, Ante VUJIĆEur. J. Entomol. 102 (2): 125-131, 2005 | DOI: 10.14411/eje.2005.020 To re-evaluate the taxonomic status of Cheilosia canicularis (Panzer, 1801), C. himantopus (Panzer, 1798) and C. orthotricha Vujić & Claussen, 1994, variation in the mitochondrial DNA (mtDNA) sequence of the cytochrome c oxidase subunit I (COI) gene and 18 nuclear allozyme genes were surveyed in allopatric and sympatric populations from Serbia and Montenegro. Genetic relationships among five populations of these species from the Fruška Gora (Serbia), Kopaonik (Serbia) and Durmitor (Montenegro) mountains were analyzed. Seven allozyme loci (Aat, Aco, Fum, Idh-1, Idh-2, Mdh-2 and Sdh) were diagnostic for delineating C. orthotricha from the other two species, while only a low, but consistent, genetic differentiation was observed between C. canicularis and C. himantopus. Differentiating all three species was possible based solely on the species-specific alleles at the Est-? locus. Sequence comparisons of 738 bp of the COI gene from eleven specimens was consistent with the variability in nuclear allozymes. Sequence data revealed variation in 5% of the nucleotide sites among C. orthotricha and the C. canicularis/C. himantopus pair, while less variation (0.68%) was observed within the pair C. canicularis/C. himantopus. However, the presence of one diagnostic allozyme locus and five consistently variable nucleotide sites in sympatric populations of C. canicularis and C. himantopus (Durmitor, Montenegro) suggest that these two species have separate gene pools. |
BOOK REVIEW: Grimaldi D. & Engel M. 2005: Evolution of the Insects.B. HEMINGEur. J. Entomol. 103 (1): 273-275, 2006 | DOI: 10.14411/eje.2006.034 Cambridge University Press, New York and Cambridge, xv + 755 pp., 41 tables, 862 figs, glossary, index. ISBN 0-521-82149-5 Cloth. Price USD 75.00. |
BOOK REVIEW: Laštůvka Z. & Laštůvka A.: The Sesiidae of Europe.J. JAROŠEur. J. Entomol. 98 (3): 294, 2001 | DOI: 10.14411/eje.2001.049 Apollo Books, Stenstrup, 2001, 245 pp. |
BOOK REVIEW: Ben-Dov Y. & German V.: A Systematic Catalogue of the Diaspididae (Armoured Scale Insects) of the World, Subfamilies Aspidiotinae, Comstockiellinae and Odonapidinae. Ben-Dov Y.: A Systematic Catalogue of the Scale Insect Family Margarodidae (Hemiptera: Coccoidea) of the World. Miller D.R., Gimpel M.E. & Rung A.: A Systematic Catalogue of the Cerococcidae, Halimococcidae, Kermesidae, Micrococcidae, Ortheziidae, Phenacoleachiidae, Phoenicococcidae, and Stictococcidae (Hemiptera: Coccoidea) of the World.J. HAVELKAEur. J. Entomol. 103 (2): 354, 2006 | DOI: 10.14411/eje.2006.046 Ben-Dov Y. & German V.: A Systematic Catalogue of the Diaspididae (Armoured Scale Insects) of the World, Subfamilies Aspidiotinae, Comstockiellinae and Odonapidinae. Intercept, Andover, UK, 2003, 1111 pp. ISBN 1-898298-93-9. Price GBP 80.00. |
BOOK REVIEW: Basset Y., Novotný V., Miller S.E. & Kitching R.L. (eds): Arthropods of Tropical Forests: Spatio-temporal Dynamics and Resource Use in the Canopy.A. AIELLOEur. J. Entomol. 103 (1): 253-254, 2006 | DOI: 10.14411/eje.2006.029 Cambridge University Press, Cambridge, 2003, xvi + 474 pp. ISBN 0-521-82000-6 (hard cover). Price USD 110.00. |
BOOK REVIEW: Drosopoulos S. & Claridge M.F. (eds) 2005: INSECT SOUNDS AND COMMUNICATION. Physiology, Behaviour, Ecology and Evolution.J. ŽĎÁREKEur. J. Entomol. 103 (4): 778, 2006 | DOI: 10.14411/eje.2006.105 CRC Press, Taylor & Francis Group, Boca Raton, London, New York, 532 pp. ISBN 0-8493-2060-7 (hardback). Price: USD 139.95. |