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Results 1171 to 1200 of 2340:

Effectiveness of two sampling methods used for collecting Ichneumonidae (Hymenoptera) in the Cabañeros National Park (Spain)

Marina MAZÓN, Santiago BORDERA

Eur. J. Entomol. 105 (5): 879-888, 2008 | DOI: 10.14411/eje.2008.116

When estimating the species richness of a taxonomic group in a specific area, the choice of the trapping method is extremely important. In this study the effectiveness of Malaise and Moericke yellow pan traps for collecting flying Ichneumonidae was compared. Samples were collected in 5 habitats in the Cabañeros National Park: pastureland, shrubland and three types of woodland. Two traps of each type were placed in each habitat, and samples collected over a period of one year, replacing the pots every 20 days. The study focused on eleven subfamilies of Ichneumonidae. The results showed that the composition of the Ichneumonidae in the catches of the two traps differed. Malaise traps were more effective in collecting Ichneumonidae in all habitats, but especially in the ash woodland. Moericke traps yielded the most abundant catches in open areas with a wider field of vision. The subfamily Orthocentrinae occurred more frequently in the Moericke yellow traps. The Ichneumonidae caught by both trapping methods differed, especially in the relative abundance of the most common species. When compiling an inventory of species it is extremely important to use a combination of both trapping methods.

Flower visiting Neuroptera: Mouthparts and feeding behaviour of Nemoptera sinuata (Nemopteridae)

Harald W. KRENN, Barbara-Amina GEREBEN-KRENN, Bernhardt M. STEINWENDER, Alexi POPOV

Eur. J. Entomol. 105 (2): 267-277, 2008 | DOI: 10.14411/eje.2008.037

The mouthparts of the spoon-winged lacewing Nemoptera sinuata are adapted for the uptake of pollen and nectar. Form and function of the mouthparts are described, and the technique of food uptake is discussed in context with flower-visiting behaviour and floral architecture of the preferred flowers. The maxillae are the main organs for food uptake. The brush-shaped laciniae, galeae and maxillary palpi form a functional unit which can be extended by the action of the cardo-stipes joint. Video analyses of the mouthpart movements distinguished different patterns of maxillary motions which occur in nectar feeding or pollen collecting. The flower-visiting behaviour and the specialised mouthparts of the Nemopteridae are derived traits which probably evolved from predatory and biting/chewing mouthparts within the Neuroptera.

Phylogeny of European Dolichopus and Gymnopternus (Diptera: Dolichopodidae) and the significance of morphological characters inferred from molecular data

Marco Valerio BERNASCONI, Marc POLLET, Manuela VARINI-OOIJEN, Paul IRVINE WARD

Eur. J. Entomol. 104 (3): 601-617, 2007 | DOI: 10.14411/eje.2007.075

Dolichopodidae (over 6000 described species in more than 200 genera) is one of the most speciose families of Diptera. Males of many dolichopodid species, including Dolichopus, feature conspicuous ornaments (Male Secondary Sexual Characters) that are used during courtship. Next to these MSSCs, every identification key to Dolichopus primarily uses colour characters (postocular bristles; femora) of unknown phylogenetic relevance. The phylogeny of Dolichopodidae has rarely been investigated, especially at the species level, and molecular data were hardly ever involved. We inferred phylogenetic relationships among 45 species (57 samples) of the subfamily Dolichopodinae on the basis of 32 morphological and 1415 nucleotide characters (810 for COI, 605 for Cyt-b). The monophyly of Dolichopus and Gymnopternus as well as the separate systematic position of Ethiromyia chalybea were supported in all analyses, confirming recent findings by other authors based purely on morphology. Within Dolichopus, stable species groups could be assigned to four distinct categories on the basis of their statistical support in 7 phylogenetic analyses: (i) clades significantly supported in all analyses, (ii) clades supported in trees based on DNA and combined data, but only partly in morphological trees, (iii) clades significantly supported in trees based on DNA and combined data, but not in morphological trees, and (iv) clades consistently supported only in morphological trees. The phylogeny generated here provides a better understanding of the phylogenetic relevance of some debated morphological characters used for species and species-group characterizations in the most commonly used identification keys. In this respect, postocular bristle colour proved of little phylogenetic relevance since every group with species featuring black bristles also included species with partly yellow bristles. Entirely or partly infuscated femora explained the nodes of three stable species groups and even revealed an incorrect polarity of this morphological character in three species. Four of 6 complex MSSCs and 5 of 8 more common MSSCs were found consistently in further species groups.

Do covers influence the capture efficiency of pitfall traps?

Sascha BUCHHOLZ, Karsten HANNIG

Eur. J. Entomol. 106 (4): 667-671, 2009 | DOI: 10.14411/eje.2009.083

Pitfall traps are widely used in terrestrial ecology to capture ground-dwelling arthropods. In order to determine the effect of covers placed over pitfall traps on their efficiency at capturing of spiders, carabid beetles and ants, four types of pitfall trap were sunk into the ground at dry grassland sites: three pitfall traps were not covered, three were covered with white, three with green and three with black plastic covers. The total catch was 9,364 spiders, 4,352 carabid beetles and 4,157 ants. The distribution of species of spiders and carabid beetles, and the total catch of spiders, carabid beetles and ants did not differ significantly among the four types of trap. Therefore, covers do not appear to affect the capture efficiency of pitfall traps.

Distribution and diversity of Wolbachia in different populations of the wheat aphid Sitobion miscanthi (Hemiptera: Aphididae) in China

Zhe WANG, Zuo-Rui SHEN, Yue SONG, Hong-Yue LIU, Zheng-Xi LI

Eur. J. Entomol. 106 (1): 49-55, 2009 | DOI: 10.14411/eje.2009.007

Wolbachia is a widely distributed intracellular symbiont in the reproductive tissues of arthropods. The wheat aphid Sitobion miscanthi (Takahashi) is an important agricultural pest worldwide. Wolbachia was detected in different populations of S. miscanthi in China using 16s rDNA and wsp-specific primers. Of eighteen populations eleven were infected with Wolbachia. Several strains of Wolbachia infected these S. miscanthi populations. Of the eleven infected populations, four were infected with only one Wolbachia strain and seven with double infections. This is the most systematic survey of the distribution of Wolbachia in the wheat aphid.

Changes in the volatile profile of Brassica oleracea due to feeding and oviposition by Murgantia histrionica (Heteroptera: Pentatomidae)

Eric CONTI, Claudia ZADRA, Gianandrea SALERNO, Benedetta LEOMBRUNI, Daniela VOLPE, Francesca FRATI, Cesare MARUCCHINI, Ferdinando BIN

Eur. J. Entomol. 105 (5): 839-847, 2008 | DOI: 10.14411/eje.2008.111

The mixture of volatile compounds emitted by Brassica oleracea var. sabauda changed significantly in response to feeding and/or oviposition by Murgantia histrionica (Heteroptera: Pentatomidae). Volatiles were collected from (1) healthy plants and those with (2) feeding punctures, (3) a combination of feeding punctures and oviposition, (4) feeding punctures and one hatched egg mass and (5) plants bearing only an egg mass. In the case of plants with feeding punctures or feeding punctures plus an egg mass, the volatiles were also collected at different time intervals after plants were subjected to these two treatments (0-24 h, 24-48 h and 48-72 h). Gas chromatographic and gas chromatograph-mass spectrometric analysis showed that the percent emission of several compounds changed significantly from plants subjected to the feeding and oviposition or just oviposition. Percentage of terpenes generally decreased after feeding and oviposition, although the percentage emission of (E)-β-caryophyllene from these plants and those with just feeding punctures significantly increased. Plants with just an egg mass emitted linalool de novo but not (E)-β-ocimene. The emission of jasmonates, mainly methyl jasmonate, increased from plants with feeding punctures plus an egg mass compared to those with only an egg mass. Higher percentages of the volatile glucosinolate derivatives (VGSs), mainly 4-methoxy-3-indolylacetonitrile, were emitted by plants with feeding punctures and an egg mass. The percentage emission of most of these compounds increased during the first 24 h after the treatment and then decreased over the next 24 h, except for methyl jasmonate, which remained high also 48-72 h later. The possible ecological roles of such volatiles in plant interactions with the second and third trophic levels are discussed.

Orthopteran communities in the conifer-broadleaved woodland zone of the Russian Far East

Thomas FARTMANN, Martin BEHRENS, Holger LORITZ

Eur. J. Entomol. 105 (4): 673-680, 2008

We investigate orthopteran communities in the natural landscape of the Russian Far East and compare the habitat requirements of the species with those of the same or closely related species found in the largely agricultural landscape of central Europe. The study area is the 1,200 km2 Lazovsky State Nature Reserve (Primorsky region, southern Russian Far East) 200 km east of Vladivostok in the southern spurs of the Sikhote-Alin Mountains (134°E/43°N). The abundance of Orthoptera was recorded in August and September 2001 based on the number present in 20 randomly placed 1 m2 quadrates per site. For each plot (i) the number of species of Orthoptera, (ii) absolute species abundance and (iii) fifteen environmental parameters characterising habitat structure and microclimate were recorded. Canonical correspondence analysis (CCA) was used first to determine whether the Orthoptera occur in ecologically coherent groups, and second, to assess their association with habitat characteristics. In addition, the number of species and individuals in natural and semi-natural habitats were compared using a t test. A total of 899 individuals of 31 different species were captured, with numbers ranging between 2 and 13 species per plot. Species diversity was higher in semi-natural habitats than natural habitats. There was a similar but non-significant pattern in species density. Ordination analysis indicated four orthopteran communities, which were clearly separable along a moisture and vegetation density gradient. The natural sites in the woodland area of the Lazovsky Zapovednik are characterized by species-poor and low-density orthopteran assemblages compared to the semi-natural sites. But, the natural sites have a higher diversity of habitat specialists. Our findings corroborate the hypothesis that intermediate habitat disturbance levels support particularly species-rich animal communities at high densities. Under such regimes, orthopterans presumably mostly profit from the high diversity in plant species, which generates great structural and microclimatic heterogeneity.

Sycophila pistacina (Hymenoptera: Eurytomidae): A valid species

Hosseinali LOTFALIZADEH, Gérard DELVARE, Jean-Yves RASPLUS

Eur. J. Entomol. 105 (1): 137-147, 2008 | DOI: 10.14411/eje.2008.019


Sycophila pistacina
(Rondani), which was previously synonymized with Sycophila biguttata (Swederus), is revalidated. Morphological, morphometric and molecular data confirm its status as a separate species. Diagnostic characters are provided for distinguishing it from S. biguttata. The nomenclature of the S. biguttata complex is updated.

The influence of environmental factors on the supranivean activity of flies (Diptera) in Central Poland

Agnieszka SOSZYÑSKA

Eur. J. Entomol. 101 (3): 481-489, 2004 | DOI: 10.14411/eje.2004.068

More than half of the insects collected on snow in Central Poland were flies (Diptera). Altogether 83 species of Diptera from 27 families were identified, of which 9 families were recorded for the first time. Two thirds of the Diptera belonged to the Mycetophilidae and Trichoceridae, which were also very species-rich. Other families with many species were the Heleomyzidae, Sphaeroceridae and Phoridae.
The peak activity was in the first part of December. Flies were most active on snow when the humidity ranged from 80 to 100%, temperatures between -1 to 5°C and the snow was from 20 to 40 cm deep. The occurrence of Trichoceridae was strictly associated with high humidities, in contrast to Drosophilidae and Heleomyzidae, which were most active at lower humidities. The activity of the flies of the most frequently recorded families was displaced towards either lower (Heleomyzidae and Limoniidae) or higher temperatures (Trichoceridae, Mycetophilidae). In contrast to other families, the supranivean activity of Phoridae was strictly associated with thin snow cover.

The biological characteristics and distribution of the greenbug, Schizaphis graminum, and Russian wheat aphid, Diuraphis noxia (Hemiptera: Aphididae), in Argentina and Chile

Ariel CLUA, Ana M. CASTRO, Silvia RAMOS, Daniel O. GIMENEZ, Araceli VASICEK, Hugo O. CHIDICHIMO, Anthony F.G. DIXON

Eur. J. Entomol. 101 (1): 193-198, 2004 | DOI: 10.14411/eje.2004.024

The aphids Schizaphis graminum (Rondani) (greenbug) and Diuraphis noxia (Mordvilko) (Russian wheat aphid, RWA) were collected from several localities in Argentina and Southern Chile. Clones were established from aphids collected at each location. The host preferences were studied in free choice tests. Biotypes were characterized on the basis of aphid antibiosis and host plant tolerance. The production of sexuals was assessed under natural conditions, from March to November in 1997-2001, at La Plata (34°55' S, 57°57' W). The greenbug distribution ranged from 24°40' to 43°28' S, and was bounded between isothermals 18-20°C and 8-10°C, and isohyets 400-600 mm and greater than 1200 mm. The aphids at all localities were collected from a wide range of cultivated and wild hosts. The biotypes in ten out of thirty-four populations were identified. One population was obligatorily parthenogenetic, the remainder cyclically parthenogenetic. No correlation was found between the region they came from and the period required for the induction of sexuals. RWA was found between 26°50' and 43°28' S, bounded by the isothermals 20-22°C and 8-10°C, and isohyets 400-600 mm and 2000 mm. In Chile, this aphid was only found in Osorno County, which lies on isothermal 8-10°C and is bounded by the isohyets 1000 mm and 2000 mm. Only a few RWA genotypes (clones) produced sexuals irrespective of the host they were collected from, period of the year, region, current host, or the day length and average temperature of the rearing conditions. For the first time, RWA was found infesting cultivated as well as wild oats in South America. At low latitudes, populations of both aphid species were found only infesting wild Sorghum halepensis (L).

Predation of Bradysia sp. (Diptera: Sciaridae), Liriomyza trifolii (Diptera: Agromyzidae) and Bemisia tabaci (Hemiptera: Aleyrodidae) by Coenosia attenuata (Diptera: Muscidae) in greenhouse crops

Maria Del Mar TELLEZ, Gervasio TAPIA, Manuel GAMEZ, Tomas CABELLO, Helmut F. van EMDEN

Eur. J. Entomol. 106 (2): 199-204, 2009 | DOI: 10.14411/eje.2009.025

We studied the predation behaviour of the "hunter fly" (Coenosia attenuata Stein) in the laboratory and greenhouse. In the laboratory, which was conducted at 25°C at 60-80% RH, with a 16L : 8D photoperiod, we examined the functional response of this species to three different pests, namely the sciarid fly (Bradysia sp.), the tobacco whitefly (Bemisia tabaci) and the leaf miner Liriomyza trifolii. In the greenhouse, we studied the population dynamics of the predator and its prey on pepper and water melon crops grown in southern Spain. Adult hunter flies were found to exhibit a type I functional response to adult sciarid flies and whiteflies, but a type II response to adult leaf miners. The type II response was a result of the greater difficulty in capturing and handling leaf miners compared to the other two species. The dynamics of the predator-prey interaction in the greenhouse revealed that the predator specializes mainly on adult sciarids and that the presence of the other prey can be supplemental, but is never essential for survival of the predator; this, however, is crop-dependent. The results on the dynamics of the predator-prey systems were obtained through a known population dynamics model with modifications.

Revision of Phaeochiton Kerzhner, 1964 (Heteroptera: Miridae: Phylini)

Fedor V. KONSTANTINOV

Eur. J. Entomol. 105 (4): 771-781, 2008

The genus Phaeochiton Kerzhner, 1964 is revised and P. alenae sp. n. from Mongolia is described. Differential diagnoses are provided for the genus and its three species. Illustrations of male and female genitalia, tarsus and pretarsus, photographs of the dorsal habitus, hosts, and distributional records of the species discussed are given.

Geographical patterns of chromosomal differentiation in the brachypterous grasshopper Podisma sapporensis (Orthoptera: Acrididae)

Elżbieta WARCHA£OWSKA-ĤLIWA, Haruki TATSUTA, Shin-Ichi AKIMOTO, Anna MARYAÑSKA-NADACHOWSKA, Marek KOWALCZYK, Alexander BUGROV

Eur. J. Entomol. 105 (2): 185-196, 2008 | DOI: 10.14411/eje.2008.027

The distribution patterns of the X0/XX and neo-XY/neo-XX chromosome races, subraces, and "hybrids" between subraces of the grasshopper P. sapporensis were analyzed. The origin of the observed variation is Robertsonian translocations between a sex chromosome and an autosome, and chromosome rearrangements. The fixation levels of inversions varied depending on geographic regions. No hybrid population is known implying that a strong reproductive isolation system exists in hybrids between the different chromosomal races. The probable reasons for the purity of X0 and neo-XY chromosome races and high chromosome polymorphism in contact zones between chromosomal subraces are discussed. The presence of isolating barriers between chromosome races indicates a review of the taxonomic structure of P. sapporensis is required. It is proposed to divide P. sapporensis into two sibling species, which differ in the chromosome mechanisms of the sex determination system.The analysis of the distribution of chromosomal races and subraces of P. sapporensis allows a reconstruction of the history of this species in the Okhotsk sea region.

Revision of the subgenus Lampetis (Spinthoptera) (Coleoptera: Buprestidae) of North and Central America, and the West Indies

Angélica M. CORONA

Eur. J. Entomol. 102 (4): 737-776, 2005

The species of Lampetis (Spinthoptera) Casey, 1909 of Central America, North America and the West Indies are revised and 31 species are recognized. Six species from the West Indies [L. aurata (Saunders, 1871), L. aurifera (Olivier, 1790), L. bahamica (Fisher, 1925), L. guildini (Laporte & Gory, 1836), L. straba (Chevrolat, 1867), and L. torquata (Dalman, 1823)], eight species from Mexico [L. auropunctata (Kerremans, 1893) (new record for the USA), L. chalconota (Waterhouse, 1882), L. christophi Théry, 1923, L. dilaticollis (Waterhouse, 1882), L. geniculata (Waterhouse, 1889), L. granulifera (Laporte & Gory, 1837), L. mexicana Théry, 1923, and L. obscura Thomson, 1879], three species from Mexico and Central America [L. cortesi (Laporte & Gory, 1837), L. monilis (Chevrolat, 1834), L. simplex (Waterhouse, 1882)], and three from Central America [L. hirtomaculata (Herbst, 1801) = L. insularis (Casey, 1909) syn. n.; L. lesnei (Kerremans, 1910); and L. srdinkoana (Obenberger, 1924)] are redescribed. Seven new species (L. chamela sp. n., L. colima sp. n., L. cyanitarsis sp. n., L. hondurensis sp. n., L. tigrina sp. n., L. viridicolor sp. n., and L. viridimarginalis sp. n.) are described. Three species from Mexico and the United States [L. cupreopunctata (Schaeffer, 1905), L. drummondi (Laporte & Gory, 1836), and L. webbii (LeConte, 1858)], and one species from Mexico (L. chiapaneca Corona, 2004) are not described here, because they were (re)described recently. The diagnosis, distribution, host plants and phenology data of L. chiapaneca, L. cupreopunctata, L. drummondi, and L. webbii are given. Lampetis famula Chevrolat, 1838 and L. variolosa (Fabricius, 1801) are not recognized herein as Mexican species, because they are from South America according to the literature and specimens studied. Information on variation, distribution, and host plants are given for each species. Photographs of dorsal habitus and male genitalia are included.

Aristolochic acids affect the feeding behaviour and development of Battus polydamas archidamas larvae (Lepidoptera: Papilionidae: Troidini)

Carlos F. PINTO, Alejandra J. TRONCOSO, Alejandro URZÚA, Hermann M. NIEMEYER

Eur. J. Entomol. 106 (3): 357-361, 2009 | DOI: 10.14411/eje.2009.044

The feeding behaviour of specialist butterflies may be affected by the mechanical and chemical characteristics of the tissues of their host-plants. Larvae of the butterfly, Battus polydamas archidamas feed only on Aristolochia chilensis, which contains aristolochic acids. We studied the oviposition pattern of adults and the foraging of larvae of B. polydamas archidamas over time in relation to variations in hardness of the substrate and concentration of aristolochic acids in different plant tissues. We further tested the effect of two artificial diets containing different concentrations of aristolochic acids on larval performance. B. polydamas archidamas oviposited mostly on young leaves and the larvae fed on this tissue until the second instar. Third instar larvae fed also on mature leaves and fourth and higher instars fed also on stems. Young leaves are softer and contain higher concentrations of aristolochic acids than mature leaves, and stems are both harder and contain a high concentration of aristolochic acids. Larvae reared on artificial diets containing a high concentration of aristolochic acids suffered less mortality and were heavier than those reared on a diet with a lower concentration of aristolochic acids, which suggests they are phagostimulatory. A strategy of host use regulated by aristolochic acid content and tissue hardness is discussed.

Rapid discrimination of the common species of the stored product pest Liposcelis (Psocoptera: Liposcelididae) from China and the Czech Republic, based on PCR-RFLP analysis

Meng QIN, Zhi-Hong LI, Zuzana KUÈEROVÁ, Yang CAO, Václav STEJSKAL

Eur. J. Entomol. 105 (4): 713-717, 2008

Psocids of the genus Liposcelis (Psocoptera: Liposcelididae) are stored product pests that are difficult to identify morphologically. A molecular method based on Restriction Fragment Length Polymorphism (RFLP) of the PCR-amplified 16S rDNA gene was developed for the rapid discrimination of four common species (L. bostrychophila, L. entomophila, L. decolor, and L. paeta). Different developmental stages and populations (P.R. China and Czech Republic) were tested. One DNA fragment of about 500 bp in length was amplified from genomic DNA and the fragment was then digested using the restriction endonuclease DraI. Identification of the relevant banding pattern allowed all the developmental stages and both sexes to be discriminated in the species tested. The banding patterns of L. entomophila from all populations were identical, while the relevant restriction digests and sequence analysis confirmed that the Chinese and Czech populations of L. bostrychophila, L. decolor, and L. paeta differed. In conclusion, PCR-RFLP with one pair of primers (16Sar and 16Sbr) and one restrictive endonuclease, DraI, proved a reliable method for rapidly discriminating the Liposcelis species tested.

Revision of New World Loxocera (Diptera: Psilidae), with phylogenetic redefinition of Holarctic subgenera and species groups

Matthias BUCK, Stephen A. MARSHALL

Eur. J. Entomol. 103 (1): 193-219, 2006 | DOI: 10.14411/eje.2006.022

The New World species of Loxocera Meigen are revised including two new species, L. (Imantimyia) ignyodactyla Buck sp. n. from Costa Rica (first record of the genus from the Neotropical region) and L. (Imantimyia) ojibwayensis Buck sp. n. from Ontario, Canada. Loxocera californica Capelle is synonymized with L. collaris Loew and lectotypes are designated for L. pleuritica Loew and L. cylindrica var. obsoleta Johnson (both synonyms of L. cylindrica Say). The New World species are diagnosed and a key to species is provided. The male and female terminalia of Loxocera are described in detail for the first time, and their functional morphology is discussed. Eggs of most species are described and a key to the known eggs of Loxocera is provided. A phylogenetic framework for the Holarctic subgenera and species groups of Loxocera is developed based on morphological characters of the adult flies. The Old World subgenus Platystyla Macquart is synonymized with Loxocera s. str., and Imantimyia Frey is reinstated as a valid subgenus including all Holarctic species previously placed in Loxocera s. str. except the L. aristata species group. This leads to the following new subgeneric combinations: L. (L.) malaisei Frey comb. n., L. (L.) matsumurai Iwasa comb. n., L. (L.) monstrata Iwasa, comb. n., and L. (L.) omei Shatalkin comb. n. The species groups of Imantimyia are redefined, i.e. the L. achaeta-group (7 spp.), the L. fulviventris-group (4 spp.), and the L. albiseta-group (1 sp.). The Oriental subgenus Asiopsila Shatalkin is referred to Psila Meigen s. l. as a subgenus based on characters of the egg, resulting in fourteen new generic combinations: Psila (Asiopsila) brevibuccata (Shatalkin) comb. n., P. (A.) burmanica (Frey) comb. n., P. (A.) decorata (de Meijere) comb. n., P. (A.) derivata (Shatalkin) comb. n., P. (A.) formosana (Hennig) comb. n., P. (A.) freidbergi (Shatalkin) comb. n., P. (A.) humeralis (de Meijere) comb. n., P. (A.) kambaitensis (Frey) comb. n., P. (A.) limpida (Shatalkin) comb. n., P. (A.) maculipennis (Hendel) comb. n., P. (A.) michelseni (Shatalkin) comb. n., P. (A.) pleuralis (Frey) comb. n., P. (A.) primigena (Shatalkin) comb. n., and P. (A.) vittipleura (Shatalkin) comb. n.

Establishment of ant communities in forests growing on former agricultural fields: Colonisation and 25 years of management are not enough (Hymenoptera: Formicidae)

Wouter DEKONINCK, Konjev DESENDER, Patrick GROOTAERT

Eur. J. Entomol. 105 (4): 681-689, 2008

Ants are often considered as good indicators of change of management in different habitats. They have been used sporadically to evaluate large scale transformations involving reafforestation. In the present study, the ant assemblages at 15 forest sites are compared. The sites differ in history, age and forest management. Our results show that there are clear changes in ant assemblages with developmental stage but even after 25 years not all forest species are present. Natural succession and planting of trees with or without any other management, resulted in only open country species, and some from forest and wet grassland colonizing these new forests. Sometimes gynes of target forest species arrived in new forests from nearby mature forest, but apparently were unable to start a colony. We attribute this findings to the lack of appropriate vegetation structure and litter characteristics, which determines the forest ant fauna, more than the dispersal of ant gynes. Further investigations should enable us to predict if these conditions can be produced by 50-100 or more years of forest succession and adequate management.

Plant architecture and vegetation structure: Two ways for insect herbivores to escape parasitism

Elisabeth OBERMAIER, Annette HEISSWOLF, Hans Joachim POETHKE, Barbara RANDLKOFER, Torsten MEINERS

Eur. J. Entomol. 105 (2): 233-240, 2008 | DOI: 10.14411/eje.2008.033

Interactions between herbivorous insects and their parasitoids occur in highly structured and complex environments. Habitat structure can be an important factor affecting ecological interactions between different trophic levels. In this study the influence of plant architecture and surrounding vegetation structure on the interaction between the tansy leaf beetle, Galeruca tanaceti L. (Coleoptera: Chrysomelidae) and its egg parasitoid, Oomyzus galerucivorus Hedqvist (Hymenoptera: Eulophidae), was investigated at two small spatial scales in the field. It was expected that high and structurally complex plants or vegetation represent an enemy free space for the herbivore by making host search more difficult for the parasitoid. At the scale of individual plants, plant height had a positive influence on herbivore oviposition and egg clutch height a negative impact on parasitism. In addition, the beetle was more likely to oviposit on simple plants than on plants with branches, while the parasitoid remained unaffected by the degree of branching. At the microhabitat scale (r = 0.1 m around an oviposition site), both height and density of the vegetation affected beetle oviposition positively and egg parasitism negatively. The herbivore and its parasitoid, therefore, were influenced in opposite ways by habitat structure at both spatial scales investigated, suggesting the existence of an enemy free space for the herbivores' eggs on tall plants and in tall and complex vegetation. This study indicates that structural components of the environment are important for interactions among organisms of different trophic levels.

Redescription of a weevil Paramecops sinaitus (Coleoptera: Curculionidae: Molytinae) from the Sinai and an ecological study of its interaction with the Sinai milkweed Asclepias sinaica (Gentianales: Asclepiadaceae)

Tim NEWBOLD, Massimo MEREGALLI, Enzo COLONNELLI, Maxwell BARCLAY, Shereen ELBANNA, Nancy ABU FANDUD, Frank FLEGG, Rasha FOUAD, Francis GILBERT, Vanessa HALL, Claire HANCOCK, Mona ISMAIL, Samr OSAMY, Isra'a SABER, Fayez SEMIDA, Samy ZALAT

Eur. J. Entomol. 104 (3): 505-515, 2007 | DOI: 10.14411/eje.2007.071

We collected specimens of Paramecops sinaitus (Pic, 1930) (Curculionidae: Molytinae) from south Sinai in Egypt, which enabled us to make the first complete description of this species. We also include some taxonomic remarks on the genus. Paramecops solenostemmatis (Peyerimhoff, 1930) is a synonym of Paramecops sinaitus. We propose the new combination Paramecops sogdianus (Nasreddinov, 1978), based on Perihylobius sogdianus Nasreddinov, 1978, which would make Perihylobius and Paramecops synonymous. Like other Paramecops species, P. sinaitus appears to share a close interaction with Asclepiads, in this case the Sinai milkweed Asclepias sinaica (Boiss.) Muschl., 1912 (Asclepiadaceae). We investigated the oviposition behaviour of female weevils to test whether it is linked to larval performance, as predicted by coevolutionary theory. We found that female oviposition preference was positively related to plant size and to the volume of the seed follicles in which the eggs were laid. The survival of eggs was negatively related to plant size, perhaps due to plant differences in the production of defensive cardenolides. Larval survival was not related to plant size but increased with follicle volume, probably as a result of competition for food. Paramecops is relatively sedentary and nocturnal in its behaviour. Night-time observations of behaviour showed that weevils were more active at lower temperatures.

Revision of the bee genus Capicola (Hymenoptera: Apoidea: Melittidae) distributed in the Southwest of Africa

Denis MICHEZ, Connal EARDLEY, Michael KUHLMANN, Sébastien PATINY

Eur. J. Entomol. 104 (2): 311-340, 2007 | DOI: 10.14411/eje.2007.048

The bee family Melittidae (Hymenoptera: Apoidea) includes 14 genera. Most have been reviewed but not the small African genus Capicola. The present work aims to fill this gap. Based on the revision of the type material and 1272 additional specimens, we provide a comprehensive synonymic and annotated catalogue of the 12 Capicola species sensu Michener (1981). Lectotypes are designated for the previously established species Capicola braunsiana (= C. obscura syn. n.), C. cinctiventris, C. femorata, C. flavitarsis and C. rufiventris. Moreover, C. danforthi sp. n., C. flavicara sp. n., C. gessorum sp. n., C. micheneri sp. n., and C. richtersveldensis sp. n., are newly described, as well as the previously unknown female of C. nanula, male of C. nigerrima and male of C. rhodostoma. New synonymies are proposed for C. braunsiana (= C. obscura) and C. flavitarsis (= C. cinctiventris). An original dataset of 20 morphological characters is used for the inference of the 12 species' phylogenetic relationship. A key to species is provided. In addition, the ranges of the 12 taxa are mapped and discussed. This paper contributes to a global revision of the Melittidae.

The Empis (Coptophlebia) hyalea-group from Thailand, with a discussion of the worldwide distribution of this species group (Diptera: Empididae: Empidinae)

Christophe DAUGERON, Patrick GROOTAERT

Eur. J. Entomol. 100 (1): 167-179, 2003 | DOI: 10.14411/eje.2003.026

The Empis (Coptophlebia) hyalea-group is especially diversified in the Oriental region and is here partly reviewed. Twelve new species from Thailand are described and keyed, namely Empis (Coptophlebia) atratata sp. n., E. (C.) kosametensis sp. n., E. (C.) lamruensis sp. n., E. (C.) miranda sp. n., E. (C.) nahaeoensis sp. n., E. (C.) nganga sp. n., E. (C.) pakensis sp. n., E. (C.) pseudospinotibialis sp. n., E. (C.) pulchra sp. n., E. (C.) ratburiensis sp. n., E. (C.) spinotibialis and E. (C.) thapensis sp. n. The group is recorded for the first time from the Nearctic and Neotropical regions, and is presently known to be distributed in tropical and subtropical regions of Central America, Africa, Southeast Asia and Australasia, and Southwestern North America.

Patterns of morphometric variation among species of the genus Cicada (Hemiptera: Cicadidae) in the Mediterranean area

Paula Cristina SIMÕES, José Alberto QUARTAU

Eur. J. Entomol. 106 (3): 393-403, 2009 | DOI: 10.14411/eje.2009.050

Selected populations of five closely related species of the genus Cicada L. were collected mainly on the Portuguese, Greek and Turkish mainland, as well as on several Aegean islands. Ten morphometric traits of external structures and seven of male genitalia were analysed and the results revealed patterns in morphometric variation for each species. Only C. lodosi was always completely discriminated by both character sets and C. barbara by the male genitalia analysis. For the remaining species there was great overlap between the clusters. Body length, of the external morphological structures, and measurements of the pygophore, of the male genitalia, were the best variables for identifying C. lodosi and C. barbara. The present morphometric analyses revealed that divergence in morphology is much less pronounced than the divergence in acoustic signals and DNA. Thus, the congruence between morphological divergence, namely at the level of the external structures, and both behavioural (acoustic) and genetic divergence is quite low.

Life tables and demographic statistics of Russian wheat aphid (Hemiptera: Aphididae) reared at different temperatures and on different host plant growth stages

Zhanshan (Sam) MA, Edward J. BECHINSKI

Eur. J. Entomol. 106 (2): 205-210, 2009 | DOI: 10.14411/eje.2009.026

Laboratory experiments were used to investigate the influences of 25 combinations of temperature and barley plant growth stage (5 × 5 factorial combination of temperature and barley plant growth stage) on the development, survival and reproduction of the Russian wheat aphid (RWA), Diuraphis noxia (Mordvilko). For each of the 25 treatments, the developmental time and nymphal production of 72 RWA individuals were recorded (1800 RWA in total) throughout their entire lifetimes. The collected data were used for analyzing demography, modelling phenology, and simulating population growth of RWA. In this paper, the results of demographic analyses are reported. Specifically, for each treatment, cohort life tables, reproductive heterogeneity tables (parity and birth intervals), and reproductive schedule tables were constructed, and demographic parameters such as intrinsic rate of increase, life-span, fecundity, life table entropy, etc. calculated. Based on these analyses, the most important summary demographic statistics are reported. Using the intrinsic rate of increase (rm) as an example, a procedure is demonstrated that builds a dynamic rm model by applying the Best Subset Regression approach. A more comprehensive (considering reproductive heterogeneity and schedule tables) yet concise (comprising dynamic rm models) demographic model than that based on standard life table analysis alone is presented.

Genetic diversity in European pollen beetle, Meligethes aeneus (Coleoptera: Nitidulidae), populations assessed using AFLP analysis

Nadiya KAZACHKOVA, Johan MEIJER, Barbara EKBOM

Eur. J. Entomol. 105 (5): 807-814, 2008 | DOI: 10.14411/eje.2008.107

The pollen beetle (Meligethes aeneus) is one of the most important insect pests of oilseed rape (Brassica napus), and extensive use of insecticides is required to protect crop yields. To meet the challenges set by agricultural demands for more sustainable production and changing climate more information about pest biology and population genetics is needed. Using genomic Amplified Fragment Length Polymorphism (AFLP) analysis, DNA polymorphism was studied in 14 field populations of pollen beetles, collected during 2004 in six European countries (Denmark, France, Finland, Germany, Sweden, and UK). Using one primer combination 410 polymorphic DNA fragments were obtained based on analysis of single beetles. AFLP profiles were analysed with similarity measures using the Nei and Li coefficient and dendrograms generated. Dendrograms constructed from distance matrices revealed clustering by population origin and assignment analysis generally supported the genotype classification. Principal component analysis of the fourteen groups resulted in wide dispersion but also connections between some groups. Statistical analysis using AMOVA showed that the levels of genetic variation within populations explained most of the variation. Migrant analysis suggested a low level of gene flow between pollen beetle populations at different geographical locations indicating little long range dispersal of pollen beetles. However, a Mantel test found no correlation between genetic and geographical distance. Apparently genetic differentiation among populations has a complex background and may involve factors such as local adaptation and founder effects.

Habitat use and movement patterns in the endangered ground beetle species, Carabus olympiae (Coleoptera: Carabidae)

Matteo NEGRO, Achille CASALE, Luca MIGLIORE, Claudia PALESTRINI, Antonio ROLANDO

Eur. J. Entomol. 105 (1): 105-112, 2008 | DOI: 10.14411/eje.2008.015

One of the most compelling challenges for conservation biologists is the preservation of species with restricted ranges. Carabus olympiae Sella, 1855, a ground beetle species inhabiting two small areas in the western Italian Alps, is an example of a steno-endemic and endangered insect species. Despite the fact that this species is historically well known to professional and amateur entomologists, its autecology is virtually unknown. In the present study we used pitfall traps to study habitat selection and phenology, and radiotelemetry to measure differences in movement parameters between sexes, habitats and periods. Data from pitfall trapping suggested that C. olympiae actively selects both shrubberies (alpen rose Rhododendron ferrugineum and bilberry Vaccinium myrtillus) and beech forests and avoids pastures, and that population size peaks in July. All radio-tagged individuals (n = 21) moved without a preferred direction, and were more active at night than by day. Males covered greater distances and had more tortuous trajectories than females. Distances covered in forests and alpen rose shrubberies were not significantly different, but paths in beech forests were more convoluted than in shrubberies. The movement pattern observed fits the requirements of a typical "olfactory-tactile" insect predator that looks for prey by systematically exploring its territory. Movement parameters suggested that both beech forests and alpen rose shrubberies are suitable for this species and indicated that the spatial distribution of shrubs in shrubberies can constrain trajectories. The implications for conservation are: (i) any human intervention which results in enlargement of the present coverage of pastures should be controlled; (ii) forest management may be tolerated, with the condition that alpen rose shrubberies remain or develop after tree-cutting; (iii) once a shrubbery has established, it should be preserved through appropriate management.

Population structure and speciation in the dragonfly Sympetrum striolatum/nigrescens (Odonata: Libellulidae): An analysis using AFLP markers

Katharine A. PARKES, William AMOS, Norman W. MOORE, Joseph I. HOFFMAN, Janet MOORE

Eur. J. Entomol. 106 (2): 179-184, 2009 | DOI: 10.14411/eje.2009.021

There has been a long-standing debate as to whether Sympetrum striolatum (Charpentier, 1840) and the darker northern form, S. nigrescens (Lucas, 1912) should be recognised as separate species of dragonfly. Here we address this question using genetic analysis based on AFLP markers and samples collected from sites across the species' United Kingdom range. The program STRUCTURE finds no support for specific status. Instead, it reveals strong patterns of divergence between populations sampled from Scottish islands and those on the mainland, suggesting that salt water is a major barrier to gene flow. Thus, the dark form is quite likely to reflect a beneficial polymorphism that allows individuals to take advantage of short periods of warmer weather. Our AFLP markers appear to be very rapidly evolving, showing little or no overlap between congeneric species, and hence are ideally suited to answering questions relating to the levels of gene flow among populations within species.

Taxonomy of the genus Amphiareus (Heteroptera: Anthocoridae) in Southeast Asia

Kazutaka YAMADA

Eur. J. Entomol. 105 (5): 909-916, 2008 | DOI: 10.14411/eje.2008.118

Four species of the genus Amphiareus are recognized in southeastern Asia, including two new species, A. edentulus and A. rompinus, both from Johor, Malaysia. The two known species, A. constrictus (Stål) and A. ruficollaris Yamada & Hirowatari are also diagnosed and figured; the latter is recorded from this region for the first time. The genus is diagnosed and briefly discussed.

How small you can go: Factors limiting body miniaturization in winged insects with a review of the pantropical genus Discheramocephalus and description of six new species of the smallest beetles (Pterygota: Coleoptera: Ptiliidae)

Vasily V. GREBENNIKOV

Eur. J. Entomol. 105 (2): 313-328, 2008 | DOI: 10.14411/eje.2008.039

The recently described and originally monotypic genus Discheramocephalus Johnson, 2007 from the Solomon Islands is revised. Six new species are described, illustrated and keyed: Discheramocephalus brucei sp. n. (Cameroon), D. elisabethae sp. n. (Cameroon), D. mikaeli sp. n. (Tanzania), D. stewarti sp. n. (Bolivia), D. jarmilae sp. n. (Bolivia), D. minutissimus sp. n. (Indonesia). Adults of D. minutissimus have a body length of about 400-426 µm, which is at the lower limit among non-egg-parasitoid insects. Evidence is provided that an egg size large enough to produce a viable larva is the main factor limiting miniaturisation of female insects. Females and males of egg-parasitoids are able to overcome the 400 µm threshold and reach limits of 180 µm and 130 µm, respectively. Brain size is likely the second most important factor limiting miniaturisation in insects.

Intronic sequences of the silkworm strains of Bombyx mori (Lepidoptera: Bombycidae): High variability and potential for strain identification

Kee Young KIM, Eun Lee MEE, In Lee HEE, Mee Hong YEON, Pil Don KANG, Kwang Ho CHOI, Zhong Zheng GUI, Byung Rae JIN, Jae Sam HWANG, Kang Sun RYU, Yeon Soo HAN, Iksoo KIM

Eur. J. Entomol. 105 (1): 73-80, 2008 | DOI: 10.14411/eje.2008.010

We sequenced nine introns of 25 silkworm (Bombyx mori L.) strains, assuming that the introns are particularly prone to mutation. Mean sequence divergence and maximum sequence divergence in each intronic sequence among 25 silkworm strains ranged from 0.81% (3.8 nucleotides) ~ 9.15% (85.2 nucleotides) and 1.2% (seven nucleotides) ~ 39.3% (366 nucleotides), respectively. The degree of sequence divergence in some introns is very variable, suggesting the potential of using intronic sequences for strain identification. In particular, some introns were highly promising and convenient strain markers due to the presence of a large indels (e.g., 403 bp and 329 bp) in only a limited number of strains. Phylogenetic analysis using the individual or the nine concatenated intronic sequences showed no clustering on the basis of known strain characteristics. This may further indicate the potential of the intronic sequences for the identification of silkworm strains.

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