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Vindobonella leopoldina gen. n., sp. n. from Austria (Protura: Acerentomidae s. l.)Andrzej SZEPTYCKI, Erhard CHRISTIANEur. J. Entomol. 98 (2): 249-255, 2001 | DOI: 10.14411/eje.2001.041 A new genus, Vindobonella gen. n. (Acerentomidae s. l.), and a new species, Vindobonella leopoldina sp. n., are described from Vienna. The new genus belongs to a group characterized by a reduced labial palp and a non-modified striate band on abdominal segment VIII. |
Oviposition strategy of the green lacewing Chrysoperla rufilabris (Neuroptera: Chrysopidae) in response to extraguild prey availabilityBruno FRÉCHETTE, Daniel CODERREEur. J. Entomol. 97 (4): 507-510, 2000 | DOI: 10.14411/eje.2000.078 The capacity of the green lacewing Chrysoperla rufilabris (Burmeister) to modify its oviposition strategy in response to extraguild prey availability in an oviposition site was studied. Gravid females were placed in presence and absence of aphids. Fecundity, fertility, dispersion and hatching synchrony were compared. Results indicate a statistical difference in the hatching synchrony of eggs. However, no statistical differences were observed in the proportion of infertile eggs and in egg dispersion. We suggest that C. rufilabris can alter hatching synchrony of eggs in condition of food scarcity in order to favour intra-clutch egg cannibalism by newly hatched larvae and thus increase its overall reproductive success. |
Host-instar selection in the aphid parasitoid Monoctonus paulensis (Hymenoptera: Braconidae, Aphidiinae): a preference for small pea aphidsAmanda CHAU, Manfred MACKAUEREur. J. Entomol. 97 (3): 347-353, 2000 | DOI: 10.14411/eje.2000.052 Monoctonus paulensis is a solitary parasitoid of several species of aphids, including the pea aphid, Acyrthosiphon pisum. We evaluated host-instar selection by comparing the parasitoid's preference for the four nymphal instars of the pea aphid, presented two at a time in dichotomous choice tests. Females parasitized more, and laid more eggs in, the relatively smaller aphids among those available. This preference was independent of aphid instar: L1 > L2 > L3 > L4. Preference was not influenced by female size or age. Normal and anaesthetized aphids were accepted equally. The total time needed by a female to capture, position, and parasitize an aphid varied among host instars, with fourth instars requiring nearly twice as much time as first, second, and third instars. The probability of an attacked aphid escaping or avoiding parasitism increased with aphid instar, from ~10% in first and second instars to ~50% in fourth instars. Although fourth-instar pea aphids contain more resources for offspring development than smaller counterparts, it may not be profitable for a female to invest opportunity time in attacks on large aphids. |
Cold hardiness of Pyrrhocoris apterus (Heteroptera: Pyrrhocoridae) from central and southern EuropePlamen KALUSHKOV, Oldřich NEDVĚDEur. J. Entomol. 97 (2): 149-153, 2000 | DOI: 10.14411/eje.2000.027 The cold hardiness of individuals from overwintering populations of a freeze susceptible bug Pyrrhocoris apterus from central and southern Europe differed significantly. Supercooling point (SCP) correlated well with both lethal temperature (LT50) and lethal time (Lt50), and is agood index of cold hardiness of adults during and after diapause. In January, diapause terminated, but cold hardiness was similar to that recorded in November; cold hardiness decreased slightly in March and markedly in May. Short exposure (less than a week) to higher temperatures before termination of diapause did not reduce the cold hardiness. Cold hardiness did not closely follow air temperatures.The Bulgarian bugs retained lower cold hardiness regardless of acclimation to harsh field conditions in the Czech Republic. The interpopulation difference is therefore a heritable character representing an adjustment to local climates. |
The relationship between water content and cold tolerance in the arctic collembolan Onychiurus arcticus (Collembola: Onychiuridae)WORLAND M.R.Eur. J. Entomol. 93 (3): 341-348, 1996 The arctic collembolan Onychiurus arcticus is freezing intolerant and experiences temperatures below -25°C during winter periods of low air temperatures and only light snow cover. Summer-collected individuals have a mean (±SE) supercooling point of -6.1 ± 0.1°C. This study was designed to measure the desiccation resistance and subsequent recovery of O. arcticus from partial dehydration and relate these to its cold-hardiness in terms of changes in the supercooling point (SCP) and solute concentration. Drying curves measured with a recording microbalance showed two distinct phases characteristic of the loss of free and chemically bound (osmotically inactive) water. Rates of water loss at 0°C and low relative humidity (< 5%) were similar to those measured for Antarctic Collembola (5% h-1 of the initial total water content). O. arcticus survived losses of 40% of its total body water content and recovered within 36 h but could not survive losses of 50% of its original water content. Differential scanning calorimetry was used to investigate the nature of the body water, i.e. the proportion of freezable to unfreezable water and the nucleation temperature. The melt onset temperature correlated positively with the body water content. But no clear relationship was seen between the water content and the SCP, either because the springtails had low levels of cryoprotectants or because the ice nucleation activity was unaffected. However, long periods (7 months) at -2.5°C reduced the water content from 74 ± 10.1 to 43 ± 7.2% of fresh weight and lowered the SCP from -6.1 ± 2.1 to -15.5 ± 2.3°C. When given access to water these individuals re-gained their body weight within 24 h. During periods of desiccation water losses were attributed to the loss of freezable water with the unfreezable portion remaining almost constant at 16.5 ± 2.0%. It appears that O. arcticus may experience a reduction of body water during winter periods of sub-zero temperatures, which may lower its SCP and enhance its cold tolerance but that it can rapidly return to summer levels given access to free water during the spring melt. |
Dorsal sex pheromone glands in female Geometridae (Lepidoptera: Geometroidea): a new apomorphy of the familyAmel BENDIBEur. J. Entomol. 98 (2): 195-199, 2001 | DOI: 10.14411/eje.2001.036 The female Geometridae are characterized by the presence of saccular pheromone glands. They are paired structures, invaginated anteriorly and located dorso-laterally to the rectum. The opening of dorsal saccular glands varies from wide to narrow and opens up on the 9th abdominal segment. These saccular glands are widely distributed in the family. Morphological variability of these glands can be observed. In certain species of Geometridae, the paired glands vary from short to long. Pheromone production is an established function of these glands, in the case of Rheumaptera hastata. |
Functional anatomy of the spermatheca and its duct in the seed bug Lygaeus simulans (Heteroptera: Lygaeidae)Robert GSCHWENTNER, Andreas TADLEREur. J. Entomol. 97 (3): 305-312, 2000 | DOI: 10.14411/eje.2000.047 Female genitalia of lygaeid bugs are characterized by a tube-shaped ductus receptaculi (spermathecal duct) connecting the bursa copulatrix with the highly coiled receptaculum seminis (spermatheca). In this study the morphology and functional anatomy of these structures in Lygaeus simulans were examined by light-, fluorescence- and electron microscopy. In addition, copulating animals were freeze fixed and their interconnected genital structures observed using light microscopy. The ductus receptaculi is separated from the receptaculum seminis by a complicated valve. The valve is nearly surrounded by the spermathecal muscle, which controls its opening. The ductus receptaculi leads into the proximal convoluted tube of the receptaculum seminis. Both the ductus receptaculi and the convoluted tube are composed of a single layer of epithelial cells lined by a thick electron dense apical cuticle. The distal part of the receptaculum seminis is a brownish, irregularly coiled, blind ending canal made of small epithelial cells covered with cuticle. Big glands are present in the epidermal layer. The cuticle of this distal part is much thinner and features concentric lamellae. The lumen of the receptaculum seminis cannot be expanded. For transfering sperm into the receptaculum the male aedeagus is equipped with a long, tube-like, sclerotized appendix (processus gonopori), which enlarges the ductus receptaculi considerably during copulation. For successful insemination the tip of the processus gonopori has to pass the valve. The convoluted tube, the valve and the surrounding spermathecal muscle may enable females to control insemination and egg fertilization. |
African-Arabian and Asian-Pacific "Mocis frugalis": Two distinct species (Lepidoptera: Noctuidae)Alberto ZILLIEur. J. Entomol. 97 (3): 419-426, 2000 | DOI: 10.14411/eje.2000.064 It is shown that under the name Mocis frugalis (F., 1775), considered to represent a widespread pest of graminaceous crops in the Eastern hemisphere and the Pacific, two species have been hitherto confused. Populations from Africa and Arabian Peninsula are described as Mocis proverai sp. n. The main characters which distinguish the African-Arabian M. proverai from M. frugalis of Asia and the Pacific are found in the genitalia, especially the configuration of the male vesica and female bursa copulatrix. |
Hyperparasitoid volatiles as possible foraging behaviour determinants in the aphid parasitoid Aphidius uzbekistanicus (Hymenoptera: Aphidiidae)Gert PETERSEN, Christin MATTHIESEN, Wittko FRANCKE, Urs WYSSEur. J. Entomol. 97 (4): 545-550, 2000 | DOI: 10.14411/eje.2000.084 The foraging behaviour of individual females of Aphidius uzbekistanicus Luzhetski (Hymenoptera: Aphidiidae) on oat plants with one colony of the grain aphid Sitobion avenae F. (Homoptera: Aphididae) was examined in laboratory experiments. Patch time allocation was analysed under semi-natural conditions when individual hyperparasitoid females, Alloxysta victrix Westwood (Hymenoptera: Alloxystidae) or their volatiles 6-methyl-5-hepten-2-one or a mixture of iridoid substances soaked on vermiculite dummies were present simultaneously. Patch residence times of foraging primary parasitoid females were significantly reduced in all analysed treatment groups. Attack numbers on aphids and resulting aphid mummies were also significantly reduced. The presence of hyperparasitoids or their volatiles had no influence on the proportion of time spent engaged in different behaviour by the primary parasitoid. After encounters with hyperparasitoid females or vermiculite dispensers, which had been soaked with the synthetical iridoids, A.uzbekistanicus females changed their behaviour more frequently, and they left the aphid colony at a higher rate than in the controls, where dispensers had been soaked with only pure pentane. The identification of the associated iridoid substances, produced in the hyperparasitoid mandibular glands, is briefly described and their biological significance is discussed. |
Experimental hybridisation between Aphis grossulariae and Aphis triglochinis (Sternorrhyncha: Aphididae)Rimantas RAKAUSKASEur. J. Entomol. 97 (3): 377-386, 2000 | DOI: 10.14411/eje.2000.058 Aphis triglochinis and A. grossulariae clones from southern Poland produced fertile hybrid eggs under experimental conditions. Established hybrid clones expressed normal parthenogenetic reproduction but bisexual generations were obtained only in three hybrid clones out of twenty six. Fertile F1 hybrid eggs were obtained in one hybrid clone. Morphological and host-specificity features of A. grossulariae dominated in the majority of hybrid clones. The present results do not exclude the possibility of natural hybridisation of studied aphid species. Natural hybrids may be difficult to detect because of their "pure" morphological and host-specificity features. |
Fecundity and survival of Anagyrus kamali (Hymenoptera: Encyrtidae) under different feeding and storage temperature conditionsLaurent A. SAGARRA, Charles VINCENT, Robin K. STEWARTEur. J. Entomol. 97 (2): 177-181, 2000 | DOI: 10.14411/eje.2000.034 The parasitoid, Anagyrus kamali Moursi (Hymenoptera: Encyrtidae), has been recently introduced into the Caribbean as a biological control agent against the hibiscus mealybug (HMB), Maconellicoccus hirsutus Green (Homoptera: Pseudococcidae). Storage of A. kamali that is essential for its use in biological control did not affect the longevity of female and male parasitoids (40.3 ± 14.07 and 31.7 ± 9.57 days, respectively) when kept at 20 ± 2°C in absence of hosts and fed ad libitum with droplets of pure honey. At a storage temperature of 27 ± 2°C the longevity decreased by about 10 days. Fed females did not resorb eggs during the first two weeks of storage at 20 ± 2°. Parasitoid ovogenesis ceased when ovarioles/lateral oviducts were full. The lifetime fecundity was not significantly affected by a storage at 20 ± 2°C of up to 14 days. Foraging activities and oviposition were the main factors influencing the lifespan of female A. kamali. |
The first species of Myrocheini (Hemiptera: Pentatomidae: Pentatominae) from the Palaearctic regionAHMAD I., SCHAEFER C.W., ONDER F.Eur. J. Entomol. 93 (2): 255-262, 1996 Lodosia Ahmad & Önder, gen. n., and Lodosia gonocoxa Ahmad & Önder, sp. n. are described. The single female specimen was collected some 900 km east of Ankara, Turkey, and is the westernmost representative of the pentatomine tribe Myrocheini; it is distinguished in particular by the raised tips of both pairs of the gonocoxae. Our cladistic hypothesis is that Laprius Stål is the sister group of Lodosia, and that Dollingiana Ahmad & Kamaluddin is the sister group of Lodosia + Laprius. The three genera all have remarkably wide interocular distances; and Lodosia and Laprius each has an unusually wide anteocular distance. Autapomorphies of the three genera are discussed. |
Chemotaxonomical characterisation of males of Bombus lucorum (Hymenoptera: Apidae) collected in the Czech RepublicKlára URBANOVÁ, Irena VALTEROVÁ, Oldřich HOVORKA, Jiří KINDLEur. J. Entomol. 98 (1): 111-115, 2001 | DOI: 10.14411/eje.2001.017 Labial gland secretions of 26 males of the bumblebee Bombus lucorum (L.), collected in the Czech Republic, were analysed. The secretions consisted of 60 compounds; ethyl (Z)-9-tetradecenoate was the main component (average 53%). Although the males varied in colour, their labial gland secretions were similar in composition, which indicated they belonged to one species. Chemically the B. lucorum occurring in the Czech Republic correspond to the earlier described "blonde form" of this species. |
Development of the solitary larval endoparasitoid Glyptapanteles porthetriae (Hymenoptera: Braconidae) in its host Lymantria dispar (Lepidoptera: Lymantriidae)Christa NUSSBAUMER, Axel SCHOPFEur. J. Entomol. 97 (3): 355-361, 2000 | DOI: 10.14411/eje.2000.053 The development of the solitary endoparasitic braconid Glyptapanteles porthetriae in gypsy moth larvae of different ages was studied. Host larvae were parasitized during the premolt to the 2nd instar (A-larvae), to the 3rd instar (B-larvae) or to the 4th instar (C-larvae), respectively. The percentage of successfully parasitized larvae decreased markedly with the age of the host at the time of parasitization. When parasitization occurred at the premolt to the second or third instar, parasitoid larvae successfully emerged at rates of 68% and 57%, respectively, in contrast to the 17% from larvae parasitized in the premolt to the fourth instar. In all three groups of parasitized larvae the final host instar was significantly longer than the corresponding instar of unparasitized control larvae of the same age. However, the growth and growth rate of parasitized larvae were reduced compared to control larvae. Due to the extremely low rate of successful development of G. porthetriae in C-larvae, parameters of parasitoid development were only recorded in A and B-host larvae. In both the parasitoid growth was slow during the first instar but rapidly increased during the second instar. Total developmental time of the parasitoid was significantly longer in B-host larvae, and the resultant cocoons were heavier than those that developed in A-host larvae, but proportionally fewer of the offspring were females. Within both groups the female wasps took significantly longer to develop than the males. |
BOOK REVIEW: Leather S.R. & Bland K.P.: Insects on Cherry Trees.F. KOCOUREK, A. HONĚKEur. J. Entomol. 97 (2): 154, 2000 | DOI: 10.14411/eje.2000.028 Naturalists' Handbooks 27. The Richmond Publishing, Slough, 1999, 82 pp. |
The water conserving physiological compromise of desert insectsZACHARIASSEN K.E.Eur. J. Entomol. 93 (3): 359-367, 1996 Insects living in arid tropical areas may spend long periods without access to free water, and at the end of the dry season they may be severely dehydrated. To survive under such conditions insects have developed a highly restrictive water economy, and tenebrionid beetles from arid tropical areas may lose water at a rate which is a hundred-fold lower than those of insects from humid habitats. |
Influence of host plants on specialist / generalist aphids and on the development of Adalia bipunctata (Coleoptera: Coccinellidae)Frédéric FRANCIS, Eric HAUBRUGE, Charles GASPAREur. J. Entomol. 97 (4): 481-485, 2000 | DOI: 10.14411/eje.2000.074 The aim of this work was to determine the impact of allelochemicals (glucosinolates/isothiocyanates) from Brassicaceae (Brassica napus and Sinapis alba) at two trophic levels in relation to biological control efficacy. The impact of these plants on aphid Myzus persicae (Sulzer) and Brevicoryne brassicae (L.) and ladybird Adalia bipunctata (L.) biology can be assessed by observation of several developmental parameters: mortality, development duration and adult weight. Sub-lethal toxicity can also be measured through the reproductive parameters of fecundity and/or egg viability. While both specialist and generalist aphids were positively influenced by Brassicaceae species, mixed effects are recorded in ladybird performances following the aphid species/host plant combinations. Significant differences appeared according to aphid host plant and aphid species. This work enhanced the influence of Brassicaceae plants either as cultivated species (B. napus) or as set-aside (S. alba) on both pests and beneficial insects. The allelochemical presence in plants must be taken into account in programs of integrated pest management due to their direct influence on biological control agents. |
The use of Harmonia axyridis larvae (Coleoptera: Coccinellidae) against Macrosiphum rosae (Hemiptera: Sternorrhyncha: Aphididae) on rose bushesFERRAN A., NIKNAM H., KABIRI F., PICART J.L., DE HERCE C., BRUN J., IPERTI G., LAPCHIN L.Eur. J. Entomol. 93 (1): 59-67, 1996 Third and fourth instar larvae of Harmonia axyridis were released in spring into rose beds infested by the aphid Macrosiphum rosae. These biological treatments induced stabilization or a decrease of the aphid populations. Their efficiency is comparable with that of chemical treatments performed in neighbouring rose beds and the subsequent development of aphid populations was the same after these two types of treatments. The rearing condition of H. axyridis, particularly its feeding on a substitute prey (lepidopteran eggs), the climate, particularly the rainfall and low temperatures, sometimes near the development threshold of the coccinellid, and possibly the rose bush variety did not seem to affect its potential predatory efficiency. An aphid density of more than thirty aphids per rose bush appears to be necessary for the larvae to remain on the plants, when fifty larvae were released per four bushes. |
Sexual activity in Coccinellidae (Coleoptera): a reviewIvo HODEK, Piotr CERYNGIEREur. J. Entomol. 97 (4): 449-456, 2000 | DOI: 10.14411/eje.2000.069 Although there are few studies of the sexual life of coccinellids these phenomena have attracted the interest of isolated groups of coccinellidologists. Probably the most important finding is that at least some coccinellid species (Adalia bipunctata and Harmonia axyridis) do not mate at random with the females prefering certain males. This phenomenon was first observed in Adalia bipunctata by Lusis and then studied in detail by Majerus, O'Donald, de Jong and others. In Japan, Harmonia axyridis was similarly studied by Osawa and Ueno. While the former author found that in this species (as in A. bipunctata) the colour of the elytra is most important in mate choice by females, the latter stresses that size and activity are important. Sperm competition is another interesting phenomenon, most often the sperm of the last male fertilizes the eggs (Ueno, Katakura). Obata and Hidaka have contributed in an important way to elucidating the function of the spermatophore in mating. The studies by Hodek and Ceryngier recorded the maturation and regression of testicular follicles and the relation of mating activity to diapause in four coccinellid species. In contrast to females, where induction of diapause prevents maturation of ovaries, in diapausing males the tissue of testicular follicles remains active until the temperatures decrease in late autumn. Dissection of spermathecae revealed principal difference in autumn mating activity between Coccinella septempunctata, in which 40-60% of the beetles mated before hibernation and Ceratomegilla (syn. Semiadalia) undecimnotata, which does not mate in autumn. |
Effects of conspecific and heterospecific larval tracks on the oviposition behaviour of the predatory ladybird, Harmonia axyridis (Coleoptera: Coccinellidae)Hironori YASUDA, Takumi TAKAGI, Kazunobu KOGIEur. J. Entomol. 97 (4): 551-553, 2000 | DOI: 10.14411/eje.2000.085 The effect of the oviposition deterring pheromone (ODP) in the larval tracks of conspecific and heterospecific ladybirds on oviposition in Harmonia axyridis Pallas was studied in semi natural conditions. Gravid females of H. axyridis were deterred from ovipositing on plants contaminated with conspecific larval tracks, but not on those with heterospecific tracks. H. axyridis females spent significantly less time on plants contaminated with conspecific ODP than on those with heterospecific ODP. This behaviour may account for why fewer eggs were laid on plants contaminated with conspecific ODP. |
Application of ubiquitin SSCP analysis in taxonomic studies within the subgenus Orinocarabus (Coleoptera: Carabidae: Carabus)Dieter SEDLMAIR, Roland GERSTMEIER, Ralf EINSPANIEREur. J. Entomol. 97 (3): 387-394, 2000 | DOI: 10.14411/eje.2000.059 SSCP (single-strand conformation polymorphism) analyses of ubiquitin genes were used to investigate evolutionary relationships within the subgenus Orinocarabus of the genus Carabus. After SSCP electrophoresis of PCR-amplified ubiquitin copies, population-specific band patterns were obtained. Ubiquitin-SSCP-analyses of the six central European Orinocarabus species, including three subspecies and thirteen populations, resulted in a dendrogram that differed from that based on morphology. Phylogenetic analysis of mitochondrial DNA (mtDNA) did not support the SSCP dendrogram, but was in good accordance with the taxonomy based on morphological characters. The reason for the discrepancies seems to be evolutionary conservation of the ubiquitin genes. The time that elapsed since the evolution of the closely related Orinocarabus species is too short for concerted evolution of the ubiquitin genes. |
Fitness of two phenotypes of Harmonia axyridis (Coleoptera: Coccinellidae)Antonio O. SOARES, Daniel CODERRE, Henrique SCHANDERLEur. J. Entomol. 98 (3): 287-293, 2001 | DOI: 10.14411/eje.2001.048 The coccinellid H. axyridis shows considerable intraspecific variability of elytral patterns. In this paper, we suggest that a genotype that confers a specific pattern of elytra could also confer other specific autecological attributes. The aim of this paper is to compare fitness parameters of two phenotypes (aulica and nigra). Aulica is a common morph characterized by two light red areas that nearly cover the whole elytra, leaving a narrow black border, whereas nigra is completely black; the latter is a rare morph that was naturally obtained from mass cultures. Intraspecific differences occur between H. axyridis phenotypes. The aulica phenotype is more voracious than nigra. Consumption rate of males is higher in aulica than in nigra, but there is no difference for females. Larval biomass of aulica is generally higher than that of nigra. The maximum body-weights reached by larval instars and adults are significantly higher for aulica. Aulica also has greater longevity and reproductive capacity. Only life stage duration of eggs and pre-pupae differ between the two phenotypes. Nigra shows lower fecundity and fertility. Our study showed that the strong differences in phenotype traits of the coccinellid H. axyridis could affect its fitness. |
Olfactory orientation of the seven-spot ladybird beetle, Coccinella septempunctata (Coleoptera: Coccinellidae): Attraction of adults to plants and conspecific femalesMara SCHALLER, Wolfgang NENTWIGEur. J. Entomol. 97 (2): 155-159, 2000 | DOI: 10.14411/eje.2000.029 The olfactory orientation of the aphidophagous ladybird Coccinella septempunctata L. was assessed in a Y-tube olfactometer and a choice arena. The response of the predator to 22 plants, aphid prey and conspecifics was tested. The ladybird was attracted to the odour of chopped Berberis vulgaris L. leaves, and of Tripleurospermum inodoratum (L.) Sch.-Bip. flowerheads, and males were attracted to females. Methanol extracts of B. vulgaris leaves were also attractive. |
Book Review: The Economics of Non-Human Societies.FRYNTA D.Eur. J. Entomol. 93 (2): 222, 1996 Tullock G.: The Economics of Non-Human Societies. Pallas Press, Tuscon, 1994, 87 pp. |
Overwintering of Coccinella septempunctata (Coleoptera: Coccinellidae) at different altitudes in the Karkonosze Mts, SW PolandPiotr CERYNGIEREur. J. Entomol. 97 (3): 323-328, 2000 | DOI: 10.14411/eje.2000.049 The body length variation, sex ratio, ovarian development and natural enemies (parasitoids and entomopathogenic fungi) of Coccinella septempunctata were studied during two dormancy seasons in three hibernation sites in the Karkonosze mountains: the top of Mt. ¦nieżka (1,600 m a.s.l.), the top of Mt. Szrenica (1,360 m a.s.l.) and Karpacz, the village at the foot of Mt. ¦nieżka (800 m a.s.l.). The proportion of females and mean body length increased with the altitude of the hibernaculum. Post-diapause maturation of ovaries occurred earlier in spring in females from Karpacz than from the mountain tops. The rate of parasitization of C. septempunctata by its most common parasitoid, the braconid Dinocampus coccinellae, in both seasons exceeded 70% at Karpacz and was 14-28% in the mountain top hibernacula. In contrast, the incidence of fungal infection (mainly by Paecilomyces farinosus and Beauveria bassiana) was higher in beetles overwintering on the two mountain tops. |
Galaicodytes caurelensis gen. n., sp. n., the first troglobitic species of Platynini (Coleoptera: Carabidae: Pterostichinae) from the western Palaearctic regionVicente M. ORTUÑO, José M. SALGADOEur. J. Entomol. 97 (2): 241-252, 2000 | DOI: 10.14411/eje.2000.041 This study describes Galaicodytes (gen. n.) caurelensis (sp. n.) which was captured in a limestone cave in the lower Cambric of NW Spain. It is the first known cave-dwelling Platynini in the western Palaearctic region and shows unique morphological adaptations to cave life. The taxonomic position is based on comprehensive character analysis, including external anatomical, male genitalic, and female genitalic and reproductive tract characters. Certain problems concerning its taxonomic position in relation to other genera are discussed and different ecologic and biogeographic aspects are analysed. |
Field observations, laboratory rearing and descriptions of immatures of the planthopper Hyalesthes obsoletus (Hemiptera: Cixiidae)SFORZA R.*, BOURGOIN T., WILSON S.W., BOUDON-PADIEU E.Eur. J. Entomol. 96 (4): 409-418, 1999 The cixiid planthopper Hyalesthes obsoletus Signoret is an efficient vector of the stolbur phytoplasma, the cause of various crop diseases. In the field, this monovoltine species feeds on a wide variety of woody and herbaceous plants. It overwinters as larvae on the roots of its host plants. During this study, we collected adults mainly from lavender (Lavendula angustifolia Miller), bindweed (Convolvulus arvensis L. and C. sepium L.), hoary cress (Cardaria draba L.), and occasionally from plantain (Plantago cynops L.), toadflax (Linaria striata L.), bedstraw (Galium verum L.), and mountain savory (Satureia montana L.). Fertility of field collected females from sites at two different elevations differed significantly. Fertility at 300 m (50.6 eggs per female; N = 28) was more than twice that at 900 m (22.8 eggs per female; N = 19). Only one specimen of the species was found to be parasitized by an undetermined species of Dryinidae (Hymenoptera). H. obsoletus was reared in controlled conditions on lavender. Unlike in the field, larvae developed in the laboratory at the base of the host plant and on basal shoots. Egg incubation averaged 7 ± 1.2 weeks (N = 10). Total development time from egg to adult averaged 27 ± 4 weeks (N = 5) on lavender. A morphological description of the five instars is provided. The study was supplemented by scanning electron microscopy. Particular attention was paid to the structure of the wax-plates and the absence of compound eyes in the early larval stages. |
The influence of plant structure on searching behaviour in the ladybird, Scymnus nigrinus (Coleoptera: Coccinellidae)VOHLAND K.Eur. J. Entomol. 93 (2): 151-160, 1996 The foraging behaviour of all developmental stages of the ladybird, Scymnus nigrinus, when searching for its prey, Schizolachnus pineti, on pine trees was examined. Foraging was characterized by a high inter-individual variability but patterns did not differ significantly between larvae and adults. All stages spent most of their time searching on needles, on which their prey feeds, and remained mainly in the upper and outer parts of the plant which have a higher needle density in comparison with the interior plant parts. Older stages showed a higher voracity than those younger, but all had a similar predation success when attacking an individual prey. All stages spent a high amount of observation time feeding on honeydew from S. pineti. |
Life history of Adalia bipunctata (Coleoptera: Coccinellidae) in JapanYasuyuki SAKURATANI, Yoshihito MATSUMOTO, Motoki OKA, Takahiko KUBO, Atsushi FUJII, Minatsu UOTANI, Toru TERAGUCHIEur. J. Entomol. 97 (4): 555-558, 2000 | DOI: 10.14411/eje.2000.086 Adalia bipunctata is a well-known predaceous ladybird distributed in Europe, Central Asia and North America. This species has not been recorded in Japan. Recently, we found this species in the Osaka Bay area in central Japan, and assume that it was imported with goods such as timber by ships. We studied the life history and the distribution in the Osaka Bay area since the initial discovery. The larvae and adults preyed on aphids (mainly, Periphyllus viridis) on trees such as Acer buergerianum and Rhaphiolepis umbellata. The over-wintered adults appeared in March and laid eggs. The adults emerged in spring, and were in the rolled leaves throughout the rest of the year. Thus, in Japan this ladybird is univoltine with long inactivity in adult. The life history of Japanese population of A. bipunctata differs considerably from other areas where populations are multivoltine. The developmental threshold was estimated to be 6.3°C and the sum of effective temperatures was 322.6 day-degrees for the period from egg to adult emergence. Predation on prepupae of A. bipunctata by the larvae of native species such as Harmonia axyridis was observed occasionally. |
Larval morphology and biology of two species of Aphodius (Plagiogonus) from the Iberian Peninsula (Coleoptera: Scarabaeidae: Aphodiinae)José R. VERDÚ, Eduardo GALANTEEur. J. Entomol. 97 (3): 395-401, 2000 | DOI: 10.14411/eje.2000.060 The larval morphology of Aphodius (Plagiogonus) nanus Fairmaire, 1860 and A. (P.) arenarius (Olivier, 1789) are described and redescribed, respectively. The common characters of both species, and the specific diagnostic characters are provided and discussed. The most important morphological characters of the larvae of Plagiogonus Mulsant, 1842 are the longitudinal alignment of the anterior setae of the stipes, the spatulate form of the posterior-lateral setae of the glossae of the hypopharynx, the slight development of the anal lobe slit, the form of the epitorma of the epipharynx, the slight sclerotization of the pternotormae and the relative length of second antennal segment. A key to the larvae of both species of Plagiogonus is presented along with life history data and the preferred food of these species. This study shows that A. arenarius and A. nanus feeding habits are closer to saprophagy than to coprophagy. |