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Results 1651 to 1680 of 2340:

Physiological traits of invertebrates entering cryptobiosis in a post-embryonic stage

Masahiko WATANABE, Takahiro KIKAWADA, Akihiko FUJITA, Ewa FORCZEK, Taro ADATI, Takashi OKUDA

Eur. J. Entomol. 101 (3): 439-444, 2004 | DOI: 10.14411/eje.2004.063

Cryptobiosis is the state when the metabolic activity of an organism is hardly measurable or is reversibly at a standstill. Many groups of invertebrates have this ability, and can be divided into two types according to the developmental stage in which it occurs; embryonic (eggs) or post-embryonic stages (larvae and adults). The latter must be able to reversibly regulate the physiology and biochemistry of development and cryptobiosis. There are several reviews on cryptobiosis and its regulation, but none on the physiological mechanism of cryptobiosis in chironomids. The present paper reviews the physiological traits of invertebrates entering cryptobiosis in a post-embryonic stage. These unique phenomena, which occur in a post-embryonic stage of three groups of cryptobiotic invertebrates (insects, tardigrades and nematodes) are discussed with particular reference to; 1) the behavioural and physiological adaptations of cryptobiotic invertebrates, 2) role of trehalose in cryptobiosis and 3) regulation of cryptobiosis.

Phylogeography of the Eurasian pine shoot beetle Tomicus piniperda (Coleoptera: Scolytidae)

Sarah RITZEROW, Heino KONRAD, Christian STAUFFER

Eur. J. Entomol. 101 (1): 13-19, 2004 | DOI: 10.14411/eje.2004.003

Tomicus piniperda is a pest in pine stands in Eurasia and is also found in the USA, where it has caused a decline in the abundance of pine since 1992. Knowledge of the genetic structure of pine shoot beetle populations is important for understanding their phylogeographic history and for quarantine control. In this study, European, Asian and American T. piniperda populations were analyzed by sequencing a region of the mitochondrial COI gene. Twenty-five haplotypes (HT) were detected and over 70% of these HT were found in individual areas, e.g. 5 HT in China, 5 HT in France and 3 HT in Spain. Nested clade analysis revealed that most European and the American population was in a clade containing 9 HT connected by one to two mutational steps. A second clade contained HT from France (2 HT), Spain (2 HT), Sweden (1 HT), Russia (1 HT) and China (5 HT). In this clade, one to 13 mutational steps and 13 missing or theoretical HT were detected. The third clade had 5 HT from France, Russia, Poland, Finland and Switzerland; 1 to 7 mutational steps and 5 missing or theoretical HT were detected. Although only a few significant relationships were found in the nested clade analysis, the following conclusions can be drawn: (1) T. piniperda is a polymorphic species with numerous HT throughout Europe, and HT are likely to exist regarding the missing or theoretical HT; (2) It is likely there were refugial areas in Southern Europe and Western Russia; (3) The Pyrenees formed a barrier to migration after the last ice age; (4) Chinese and European populations have been separated for at least 0.6 MYA.

A new Upper Cretaceous species of Chresmoda from Lebanon - a latest representative of Chresmodidae (Insecta: Polyneoptera inc. sed.): first record of homeotic mutations in the fossil record of insects

André NEL, Dany AZAR, Xavier MARTÍNEZ-DELCLOS, Edouard MAKHOUL

Eur. J. Entomol. 101 (1): 145-151, 2004 | DOI: 10.14411/eje.2004.019

The most recent representative of the semi-aquatic insect family Chresmodidae is described from the Lebanese Cenomanian marine lithographic limestone. Its highly specialized legs, with a high number of tarsomeres, never observed in other orders of insects, were probably adapted for water surface skating. We hypothesize the occurrence of a unique, extraordinary "antenna" mutation affecting the distal part of the legs of the Chresmodidae, maybe homeotic or affecting some genes that participate in the leg development and segmentation. The Chresmodidae had a serrate ovipositor adapted to endophytic egg laying in floating or aquatic plants. They were probably predaceous on nektonic small animals. As the Chresmodidae and the aquatic water skaters of the bug families Veliidae and Gerridae were contemporaneous during at least the Lower Cretaceous, these insects probably did not cause the extinction of this curious group.

Ground beetles (Carabidae) as seed predators

Alois HONEK, Zdenka MARTINKOVA, Vojtech JAROSIK

Eur. J. Entomol. 100 (4): 531-544, 2003 | DOI: 10.14411/eje.2003.081

The consumption and preferences of polyphagous ground beetles (Coleoptera: Carabidae) for the seeds of herbaceous plants was determined. The seeds were stuck into plasticine in small tin trays and exposed to beetle predation on surface of the ground. In the laboratory the effect of carabid (species, satiation) and seed (species, size) on the intensity of seed predation was investigated. The consumption of the generally preferred Cirsium arvense seed by 23 species of common carabids increased with body size. Seed of Capsella bursa-pastoris was preferred by small carabids and their consumption rates were not related to their size. The average daily consumption of all the carabid species tested (0.33 mg seeds . mg body mass-1 . day-1) was essentially the same for both kinds of seed. Because of satiation the consumption of seed of C. arvense provided ad libitum to Pseudoophonus rufipes decreased over a period of 9 days to 1/3-1/4 of the initial consumption rate. Preferences of P. rufipes (body mass 29.6 mg) and Harpalus affinis (13.4 mg) for the seeds of 64 species of herbaceous plants were determined. The small H. affinis preferred smaller seed than the large P. rufipes. Predation of seed present on the ground in the field was studied in 1999-2000, at Praha-Ruzyne (50°06´ N 14°16´E). Seeds were placed in stands of different crops as in the laboratory experiments and vertebrate predation was excluded by wire mesh cages. Pitfall traps placed near the cages revealed that carabids were the only seed predators active in the area. Rates of removal of seed of 6 weed species varied with crop, season, seed and site. Average rate of removal in June-August was 2.5 seeds.day-1.tray-1 and was smaller before and after this period. The rates of removal increased with increasing activity density of the carabids and paucity of seed from naturally occurring weeds, which may have satiated the carabids. In stands of winter wheat, millet and soybeans there were significant differences in the rates of removal of the seed of 43 herbaceous species. The field preferences were correlated with those established in the laboratory. Predation of seed on the ground in arable fields can be as high as 1000 seeds.m-2.day-1 and may selectively influence the quantity of seed of particular herb species that enters the soil seed bank. Seed predation thus may be an effective component of weed control on arable land, particularly at low weed densities.

Revision of the genera Nemadiopsis and Falkonemadus (Coleoptera: Leiodidae: Cholevinae)

José Ma. SALGADO COSTAS

Eur. J. Entomol. 99 (4): 505-521, 2002 | DOI: 10.14411/eje.2002.067

The genera Nemadiopsis Jeannel, 1936 and Falkonemadus Szymczakowski, 1961 are redescribed and revised. The taxonomic position of Nemadiopsis and Falkonemadus is analy sed using features of male and female genitalia. Two new subgenera, Nemadiopsicus subgen. n. and Nemadiopsella subgen. n. and five new species, Nemadiopsis (Nemadiopsis) grossicornis sp. n., N. (Nemadiopsicus) rotundatus sp. n., N. (Nemadiopsella) curvipes sp. n., Falkonemadus similaris sp. n. and F. avicularis sp. n. are described. Keys to the subgenera and species are given. Nemadiopsis (Nemadiopsis) edwardsi Jeannel, 1936 and N. (N.) irretusus Szymczakowski, 1962 are proposed as junior subjective synonyms of Nemadiopsis (N.) fastidiosus (Fairmaire et Germain, 1859).

Book Review: The Eat-a-Bug Cookbook. 33 Ways to Cook Grasshoppers, Ants, Water Bugs, Spiders, Centipedes, and their Kin.

CHALUPSKY J.

Eur. J. Entomol. 96 (4): 374, 1999

Gordon D.G.: The Eat-a-Bug Cookbook. 33 Ways to Cook Grasshoppers, Ants, Water Bugs, Spiders, Centipedes, and their Kin. Ten Speed Press, Berkeley, California, 1998, 102 pp.

Book Review: The Biology of Camel-Spiders (Arachnida, Solifugae).

BUCHAR J., RUZICKA V.

Eur. J. Entomol. 96 (4): 462, 1999

Punzo F.: The Biology of Camel-Spiders (Arachnida, Solifugae). Kluwer Academic Publishers, Boston, Dordrecht, London, 1998, 301 pp.

Descriptions of the egg case and larva of Anacaena and a review of the knowledge and relationships between larvae of Anacaenini (Coleoptera: Hydrophilidae: Hydrophilinae)

Miguel ARCHANGELSKY, Martin FIKÁČEK

Eur. J. Entomol. 101 (4): 629-636, 2004 | DOI: 10.14411/eje.2004.086

The third instar larva of Anacaena cordobana Knisch, and the egg case of Anacaena lutescens (Stephens) are described and illustrated. The taxonomic status of the immature stages of Anacaenini is clarified by comparing their morphology with that described in the literature. Larval descriptions of Anacaena and Paracymus published by Richmond (1920) are interchanged, as are the identifications of all subsequent authors based on Richmond's work. All Anacaenini genera for which larvae are known are diagnosed. A comparative morphological study of Anacaena larvae shows many similarities between Crenitis and Anacaena larvae, suggesting a close relationship between these two genera.

Some observations on the reproductive biology of the scuttle fly Megaselia andrenae (Diptera: Phoridae) at the nesting site of its host Andrena agilissima (Hymenoptera: Andrenidae)

Carlo POLIDORI, R. Henry L. DISNEY, Francesco ANDRIETTI

Eur. J. Entomol. 101 (2): 337-340, 2004

Some behavioural aspects of the reproductive biology of Megaselia andrenae Disney, a kleptoparasite of the communal bee Andrena agilissima (Scopoli), were investigated at the nesting site of its host at Isola d'Elba (Italy). The scuttle fly mates more often in the early afternoon, which coincides with the period when the provisioning flights of its host are more frequent. The presence of the flies at the host nesting site, either in copula or single, is lower in the morning. In general only the females enter the host nests immediately after a mate, in a few cases closely followed by the males. When leaving the nest, females refuse to mate again with the males waiting outside. Observations on the ovaries of the females revealed no differences, either in the number of eggs or in the length of the most mature egg, between the individuals collected in copula or when flying alone. The species is sexually dimorphic, the females being larger than males. Male size does not seem to influence the females choice for mating.

Lepidoptera of a raised bog and adjacent forest in Lithuania

Dalius DAPKUS

Eur. J. Entomol. 101 (1): 63-67, 2004 | DOI: 10.14411/eje.2004.014

Studies on nocturnal Lepidoptera were carried out on the Laukėnai raised bog and the adjacent wet forest in 2001. Species composition and abundance were evaluated and compared. The species richness was much higher in the forest than at the bog. The core of each lepidopteran community was composed of 22 species with an abundance of higher than 1.0% of the total catch. Tyrphophilous Hypenodes humidalis (22.0% of all individuals) and Nola aerugula (13.0%) were the dominant species in the raised bog community, while tyrphoneutral Pelosia muscerda (13.6%) and Eilema griseola (8.3%) were the most abundant species at the forest site. Five tyrphobiotic and nine tyrphophilous species made up 43.4% of the total catch on the bog, and three and seven species, respectively, at the forest site, where they made up 9.2% of all individuals. 59% of lepidopteran species recorded on the bog and 36% at the forest site were represented by less than five individuals. The species compositions of these communities showed a weak similarity. Habitat preferences of the tyrphobiontic and tyrphophilous species and dispersal of some of the species between the habitats are discussed.

Sex- and morph-specific predation risk: Colour or behaviour dependency?

Hans VAN GOSSUM, Tim ADRIAENS, Henri DUMONT, Robby STOKS

Eur. J. Entomol. 101 (3): 373-377, 2004 | DOI: 10.14411/eje.2004.052

The coexistence of discrete morphs within a species, with one morph more conspicuous than the other(s) is often thought to result from both sexual selection and predation. In many damselflies, sexual dimorphism occurs jointly with multiple female colour morphs. Typically, one morph is coloured like the male (andromorph), while the other(s) is not (gynomorph(s)). The mechanisms contributing to the maintenance of such female polymorphism in damselflies remain poorly understood, especially the role of predation. We tested the detectability of two different female colour morphs of the damselfly, Enallagma cyathigerum, using human observers as model predators; andromorphs were detected more frequently than gynomorphs. Field data on mortality of males and the two different female morphs due to predation or drowning were also collected, and these observations support morph-specific mortality. In natural populations predation risk was higher in males than females; gynomorphs, however, were more prone to predation than andromorphs. Differences in behaviour between morphs, rather than colour, may explain this result.

Water loss of male and female Alphitobius diaperinus (Coleoptera: Tenebrionidae) maintained under dry conditions

David RENAULT, Yann CORAY

Eur. J. Entomol. 101 (3): 491-494, 2004 | DOI: 10.14411/eje.2004.069

Survival under dry conditions was examined in males and females of Alphitobius diaperinus Panzer (Coleoptera: Tenebrionidae), a beetle of tropical origin. The range of individual responses and the effect of gender on water loss were also evaluated. Females exhibit significantly longer survival (Lt50 and Lt90) than males under desiccating conditions. Larger females beetles have a greater initial water mass and hence can tolerate greater water losses. Such beetles have longer survival under dry conditions. Males and females loose an average of 54.8 and 58.9% of their body water prior to death. The insects were inactive most of the time, when kept under dry conditions; the rate of decrease in body water was thus reduced. Beetles of both gender display a negative correlation between the rates of water loss under desiccating conditions and the duration of survival. We conclude that the difference in survival period between males and females is due to a combination of greater female tolerance to desiccation and larger body size.

Predation upon the oblique-banded leafroller, Choristoneura rosaceana (Lepidoptera: Tortricidae), by two aphidophagous coccinellids (Coleoptera: Coccinellidae) in the presence and absence of aphids

Éric LUCAS, Sophie DEMOUGEOT, Charles VINCENT, Daniel CODERRE

Eur. J. Entomol. 101 (1): 37-41, 2004 | DOI: 10.14411/eje.2004.009

Our goal has been to determine the effect of the presence of aphids on voracity (measured as number of prey eaten and biomass consumed) of Coccinella septempunctata L. and Harmonia axyridis Pallas (Coleoptera: Coccinellidae) feeding upon the oblique-banded leafroller, Choristoneura rosaceana (Harris) (Lepidoptera: Tortricidae). For each coccinellid predator, treatments using a single prey species, with either 30 first instar C. rosaceana or 100 third instars Aphis pomi DeGeer (Hemiptera: Aphididae), were compared with two-prey treatments in which the two prey species were present simultaneously. For both predators, the total number of prey killed (total prey species pooled) and the total biomass consumed were significantly higher when both prey were present than in single-prey treatments. The voracity of C. septempunctata on C. rosaceana larvae was not affected by adding A. pomi, whereas that of H. axyridis declined; the voracity of both predators on A. pomi increased when C. rosaceana larvae were added. The preference for the aphids over C. rosaceana was confirmed for both coccinellid species.

Effect of summer flush leaves of the Daimyo oak, Quercus dentata, on density, fecundity and honeydew excretion by the drepanosiphid aphid Tuberculatus quercicola (Sternorrhyncha: Aphididae)

Izumi YAO

Eur. J. Entomol. 101 (4): 531-538, 2004 | DOI: 10.14411/eje.2004.076

The aphid Tuberculatus quercicola (Matsumura), a non host-alternating species, lives on Daimyo oak, Quercus dentata Thumberg, and other species of oak. In summer there was a significant reduction in the total amino acid concentration in phloem sap of the host plant and fecundity of the aphids. There are two phenotypes of Q. dentata: one produces flush leaves in mid-July and the other does not. This study investigates the effect of the flush leaves produced by Q. dentata in summer on the density, fecundity and honeydew excretion by T. quercicola. Of 20 shoots on each of the study trees, 6-13 (average 8.8 shoots) produced secondary shoots with flush leaves. The number of aphids on flush leaves sharply increased by two-fold compared to that on mature leaves. The aphids reared on flush leaves were significantly larger and had a larger embryo number compared to those on mature leaves. These results suggest that the phloem sap of flush leaves has a high nutritive quality for aphids. However, in mid-summer and early autumn T. quercicola went into reproductive diapause regardless of whether it was reared on flush or mature leaves. Aphid colonies persisted until October even on trees that did not produce secondary leaves. These observations suggest that this aphid does not depend on secondary leaf production. Thus, the use of flush leaves does not enable T. quercicola to avoid nutritional stress in summer and the need for reproductive diapause.

Attraction of larvae of the armyworm Spodoptera litura (Lepidoptera: Noctuidae) to coloured surfaces

Ashok K. SINGH, Kailash N. SAXENA

Eur. J. Entomol. 101 (4): 697-699, 2004 | DOI: 10.14411/eje.2004.092

Attraction of first instar larvae of Spodoptera litura to different colours was studied to determine those that could be used as effective visual attractants for trapping the larvae during dispersal. The larvae were presented with cones of coloured paper. Each cone was placed in the center of a 15-cm Petri dish around the edge of which the larvae were released. Percentage of larvae arriving at the cone was recorded at 5-min intervals over a 15-min period. Differences in the percentages reflected differences in larval attraction to the different colours. The larvae were highly attracted to Foliage Green, Green Bice and Cadmium Yellow. The larvae arrived at the Scarlet Red, Ultramarine Blue, Gray, Orange, White and Black cones in percentages that were almost equal, but lower than at the Foliage Green, Green Bice and Cadmium Yellow cones. Arrival of larvae at the coloured cones increased with time, but their relative preference for different colours remained the same. This study shows that green and yellow can be used as visual attractants in Spodoptera litura larval traps.

Studying insect photoperiodism and rhythmicity: Components, approaches and lessons

Hugh V. DANKS

Eur. J. Entomol. 100 (2): 209-221, 2003 | DOI: 10.14411/eje.2003.036

Components of daily and seasonal timing systems in insects are reviewed. Photoperiod indicates seasonal position reliably, but signals can be much modified by habitat, latitude and season. Several receptor features and pigment systems are known, with different daily, seasonal and general functions, including differences between circadian and seasonal reception. Clocks can serve several different purposes, functioning as daily oscillators, interval timers or through successive requirements. The molecular functioning of circadian clocks is best known, but even so there is considerable complexity and diversity and much remains to be discovered. We know relatively little about the internal states that provide information for timed responses (such as the photoperiodic "counter"), about the central controlling mechanism, or about the effectors that transmit output signals. Nevertheless, temporal responses serve a very great range of purposes in insects, and the reported complexity in all of the components of timing systems reflects complex ecological needs across daily and seasonal intervals. The variety of components and the complexity of interactions reported (even within species), as well as the diversity of such elements as photosensitive pigments, molecular clock function and potential neurotransmitters, suggests that - unlike some earlier expectations - there is no single master clock for all timing functions in insects.
Insect photoperiodism and rhythmicity have been studied by both observational or direct approaches (examination of system elements or devices, and qualities such as survival), and by inferential or indirect approaches (such as interpretation of various responses to photoperiod, modelling, and estimating fitness). Many students work with only one approach, but the power of different approaches is not equal, and knowledge at one level may not give answers at another. These difficulties tend to limit our understanding of the linkages among components.
This overview suggests several lessons for the study of photoperiodism and rhythmicity. There are multiple elements, complex integration and a diversity of clocks, showing that different processes serve different purposes. The diversity of findings also results from the fact that different investigative approaches, which depend on the question being asked and on the perspective of the investigator, can influence the outcome of the investigation. Given these complexities, I believe that the key to interpreting photoperiodic and circadian responses is their ecological value. Notwithstanding the interest of timing mechanisms or their parts and of specific responses, daily rhythms and seasonal timing are best understood through the essential context provided by the ecological demands on the actual organisms under study.

Phylogeny of Iberian Zabrus (Coleoptera: Carabidae: Zabrini) based on mitochondrial DNA sequence

José-Fermín SÁNCHEZ-GEA, José GALIÁN, José SERRANO

Eur. J. Entomol. 101 (4): 503-511, 2004 | DOI: 10.14411/eje.2004.071

The genus Zabrus Clairville, 1806 is a Holomediterranean taxon that radiated into about a hundred species most likely during the Cenozoic. There are four endemic subgenera on the Iberian Peninsula, which include 28 species, Epomidozabrus (3 spp.), Euryzabrus (1 sp.), Platyzabrus (2 spp.) and Iberozabrus (22 spp.). A mitochondrial fragment comprising part of the cytochrome-oxidase-I, tRNAleu, and part of the cytochrome-oxidase-II genes was sequenced of most of these species. Taxa of other subgenera of Zabrus (Macarozabrus, Polysitus, Zabrus, and Pelor), six species of Amara (the putative sister taxon of Zabrus), and representatives of tribes related to Zabrini were also sequenced. The results show that the genus Zabrus is a monophyletic taxon well separated from Amara. The four subgenera endemic to the Iberian Peninsula also make up a monophyletic clade, which stresses the association between the geographic distribution and the monophyly of many supraspecific taxa within this genus. The species-rich subgenus Iberozabrus seems to be the sister taxon of the clade made up of the three other subgenera endemic to the Iberian Peninsula. The Iberozabrus species-groups proposed by Andújar & Serrano in 2001, based on morphological and geographical grounds, are only partly corroborated by the molecular phylogeny. The lack of congruence between these data sets is mainly between those species-groups with large numbers of species and more complex geographic patterns. Some cases of incongruence are possibly due to homoplasic external characters appeared by convergent evolution.

In vitro rearing of Anagrus breviphragma (Hymenoptera: Mymaridae), an egg parasitoid of Cicadella viridis (Hemiptera: Cicadellidae), from second instar larva to adult on diets without insect components

Elisabetta CHIAPPINI, Maria Luisa DINDO, Ilaria NEGRI, Luca SIGHINOLFI

Eur. J. Entomol. 101 (3): 419-422, 2004 | DOI: 10.14411/eje.2004.058

We describe here the in vitro rearing of Anagrus breviphragma Soyka, an egg parasitoid of Cicadella viridis (Linnaeus), from the second instar larva to the adult stage. Three media, containing mainly either a commercial tissue culture medium (IPL-41), skimmed milk or veal homogenate, were tested. Larval development occurred on all the diets but few larvae reached the pupal stage on the diets containing skimmed milk or veal homogenate. On the tissue culture medium, pharate adults, albeit malformed, developed. Supplementing the tissue culture medium-based diet with chicken egg yolk alone, or combined with yeast extract, further improved parasitoid development. The addition of both egg yolk and yeast extract resulted in twelve out of twenty larvae reaching the adult stage, of which only four females emerged.

Ability of primary and secondary reproductives to inhibit the development of neotenics in Kalotermes flavicollis (Isoptera: Kalotermitidae)

Jiří KINDL

Eur. J. Entomol. 101 (2): 227-230, 2004

The inhibitory potential of primary and secondary reproductives was studied using half-orphaned colonies of Kalotermes flavicollis. Both primary and secondary reproductives (neotenics) were equally effective in inhibiting the development of replacement reproductives. Single females totally inhibited the development of female secondary reproductives but did not affect the development of male secondary reproductives. Single males had neither a stimulatory nor inhibitory effect on the development of secondary reproductives. The inhibitory ability of pairs of primary reproductives shortly after dealation and at the stage of incipient colony formation (couple with the first batch of eggs) was also examined. While pairs of freshly dealated reproductives were not able to inhibit the development of neotenics, pairs of primary reproductives that had their first batch of eggs, fully inhibited the development of neotenics.

Sex ratio of apollo butterfly Parnassius apollo (Lepidoptera: Papilionidae) - facts and artifacts

Pawel ADAMSKI

Eur. J. Entomol. 101 (2): 341-344, 2004

The adult sex ratio among the genus Parnassius is usually strongly male biased and close to 2 : 1. This paper presents the results of comparative studies, on the basis of data from wild and captive reared populations of apollo butterfly in the Pieniny National Park (Western Carpathians, Poland). Sex ratio among the wild population is strongly male biased and close to 2 : 1, whereas there was no sex ratio bias among the captive population. However, among the captive individuals caught after releasing into the wild, males significantly outnumbered females. There was a significant, sex-related, difference in activity pattern recorded in the field studies: while the majority of females were observed sitting, males were usually flying. This result suggests that the observed sex ratio shifting is at least partially an artifact caused by the more cryptic behaviour of females. The sex ratio bias was more pronounced in the wild population than in captive individuals caught after releasing into wild, which suggests that difference in detectability between the sexes is not the only reason for males outnumbering females.

A general model for the life cycle of Dolichopoda cave crickets (Orthoptera: Rhaphidophoridae)

Camilla BERNARDINI, Claudio DI RUSSO

Eur. J. Entomol. 101 (1): 69-73, 2004 | DOI: 10.14411/eje.2004.015

A general model of the Dolichopoda cave cricket life cycle was produced using RAMAS/stage simulations based on the Beverton & Holt recruitment function. The model indicates the main population parameters responsible for life cycle adjustments to ecologically different cave habitats. The lack of a uniform rate of oviposition throughout adult life, combined with egg and nymphal diapause, results in regular population growth characterized by adults emerging every two years and cohorts overlapping every other year. This pattern is common in populations living in artificial caves where the scarcity of food is likely to favour individuals that synchronise their activity with the seasonal variations in the epigean habitat. In contrast, a uniform rate of oviposition throughout adult life and no egg or nymphal diapause results in a continuous reproductive activity, and the occurrence of adults all the year round. In this case, it was not possible to distinguish between cohorts. This pattern is well represented in populations inhabiting natural caves with stable food resources. The availability of data for a population that resulted from an experimental colonization allowed us to test this model.

Taxonomy of European Eristalinus (Diptera: Syrphidae) based on larval morphology and molecular data

Celeste PÉREZ-BAÑÓN, Santos ROJO, Gunilla STÅHLS, M. Angeles MARCOS-GARCÍA

Eur. J. Entomol. 100 (3): 417-428, 2003 | DOI: 10.14411/eje.2003.064

The taxonomy of European Eristalinus syrphid flies is reviewed. New data on their life histories, biological notes and a key to species using pupal characters are provided. The larvae and puparia of Eristalinus taeniops (Wiedemann, 1818) and Eristalinus megacephalus (Rossi, 1794) are described for the first time, including new morphological characters of the thoracic respiratory process of all species. The morphology of the male genitalia of E. megacephalus is described and compared with that of E. taeniops.
The results of our morphological studies of the male genitalia and molecular data (mitochondrial COI and nuclear 28S rDNA) do not support the traditional adult classification based on the patterning on the eyes (fasciate vs punctate). We present a phylogeny of the species based on molecular data. The molecular and morphological data indicate that the relationship between some species with punctate eyes and those with fasciate eyes may be closer than with other species with punctate eyes. Moreover the results of the molecular studies support two clades, which does not accord with the traditional arrangement of this group of Syrphidae.
Accordingly we propose that the characters of male genitalia stated by Kanervo in 1938 (but subsequently largely ignored) for arranging the European species of the Eristalinus-Eristalodes-Lathyrophthalmus complex, are suitable for classifying these species.

Dermaptera hindwing structure and folding: New evidence for familial, ordinal and superordinal relationships within Neoptera (Insecta)

Fabian HAAS, Jarmila KUKALOVÁ-PECK

Eur. J. Entomol. 98 (4): 445-509, 2001 | DOI: 10.14411/eje.2001.065

The Dermaptera are a small order of insects, marked by reduced forewings, hindwings with a unique and complicated folding pattern, and by pincer-like cerci. Hindwing characters of 25 extant dermapteran species are documented. The highly derived hindwing venation and articulation is accurately homologized with the other pterygote orders for the first time. The hindwing base of Dermaptera contains phylogenetically informative characters. They are compared with their homologues in fossil dermapteran ancestors, and in Plecoptera, Orthoptera (Caelifera), Dictyoptera (Mantodea, Blattodea, Isoptera), Fulgoromorpha and Megaloptera. A fully homologized character matrix of the pterygote wing complex is offered for the first time. The wing venation of the Coleoptera is re-interpreted and slightly modified. The all-pterygote character analysis suggests the following relationships: Pterygota: Palaeoptera + Neoptera; Neoptera: [Pleconeoptera + Orthoneoptera] + [Blattoneoptera + (Hemineoptera + Endoneoptera)]. Blattoneoptera share at least 15 wing apomorphies with the sistergroup Hemineoptera + Endoneoptera and none with the Orthoneoptera and Pleconeoptera; Blattoneoptera: (Grylloblattodea + (Dermaptera + Dictyoptera)); Dictyoptera: (Mantodea + (Blattodea + Isoptera). Dermaptera share 13 wing apomorphies with the sistergroup Dictyoptera. In order to document the intra-ordinal relationships of Dermaptera, 18 new characters of venation and articulation are added to an existing data set and analyzed cladistically. The following relationships are suggested (43 characters, tree length 72, CI 0.819 and RI 0.935). Dermaptera: Karschiellidae + ("Diplatyidae" + ("Pygidicranidae" + (Allostethus indicum + (Anisolabididae + ("Labiduridae" + [Forficulidae + (Chelisochidae + Spongiphoridae)]))))). The taxa in quotation marks are probably paraphyletic. Fossil Dermaptera and "Protelytroptera" show that wing-folding characters were already present in Permian ancestors. The evolution of the dermapteran wing-folding mechanism is discussed and the hindwing is presented as a working "origami" model, which will fold as in living earwigs. The functional role of the wing base in wing folding is examined. Characters in orders and other higher taxa are not independent and cannot be analyzed out of context with their groundplans. Higher systematics is dealing with diametrally different problems than species-level systematics. The necessity of using a different methodology for species-level and higher-level phylogenetics is discussed and recommendations are made.

Calling songs of sympatric and allopatric populations of Cicada barbara and C. orni (Hemiptera: Cicadidae) on the Iberian Peninsula

Sofia G. SEABRA, Gabriela PINTO-JUMA, José A. QUARTAU

Eur. J. Entomol. 103 (4): 843-852, 2006 | DOI: 10.14411/eje.2006.115

Calling songs of the sibling species Cicada barbara and C. orni were studied in sympatric and allopatric populations on the Iberian Peninsula, where the distribution ranges of both species overlap. No difference was found in any acoustic property for the sympatric and allopatric populations of C. barbara studied and only one variable (minimum frequency) was significantly different between sympatric and allopatric populations of C. orni. No hybrids with intermediate songs were found and no character displacement in the calling song was detected. It is very likely that these species were already considerably differentiated when they met on the Iberian Peninsula. Particularly, premating (or even postmating) isolating mechanisms (according to Mayr's Biological Species Concept) or different specific-mate recognition systems (in the view of the Paterson's Recognition Concept of Species) were most likely already present, which prevented hybridization between this pair of species. It is assumed that the calling songs are the most important premating isolating mechanism corresponding to the specific-mate recognition systems of these species of cicadas.

Complex phenological responses to climate warming trends? Lessons from history

Tim H. SPARKS, Kerstin HUBER, Roger L.H. DENNIS

Eur. J. Entomol. 103 (2): 379-386, 2006 | DOI: 10.14411/eje.2006.051

Responsiveness of Lepidoptera phenology to climate has been detected in a number of species during the current trend in global warming. There is still a question of whether climate signals would be evident in historical data. In this paper we examine the climatic response of 155 species of moths and butterflies collected during the period 1866-1884 in Wiltshire, southern England. In general, species responded to increased temperature in the previous October by delayed appearance and to increased temperature in the current spring by advanced appearance. Thus, differential changes in temperatures of the autumn and spring could well affect changes in the relative pattern of the phenology of species. Attributes influencing the species' ecology were examined to see if they influenced temperature responsiveness. In general, few consistent effects emerged, though responsiveness to climate was found to be greater for species eclosing later in the year, specifically to the previous autumn temperatures, and to hibernal environment, increasingly for species less exposed to air temperatures. These findings warn against expecting simple responses to climate warming.

BOOK REVIEW: Helyer N., Brown K. & Cattlin N.D. 2004: A Colour Handbook of Biological Control in Plant Protection.

O. NEDVĚD

Eur. J. Entomol. 104 (1): 164, 2007 | DOI: 10.14411/eje.2007.024

Manson, London, 2nd ed., 126 pp. ISBN 1-874545-28-6 (hardback). Price GBP 24.95.

BOOK REVIEW: Lyneborg L.: The Australian Stiletto-Flies of the Anabarhynchus Genus-Group (Diptera: Therevidae).

K. SPITZER

Eur. J. Entomol. 99 (3): 362, 2002 | DOI: 10.14411/eje.2002.046

Apollo Books, Stenstrup (DK), 2001, 256 pp.

Cicadas "dig wells" that are used by ants, wasps and beetles

Kazuo YAMAZAKI

Eur. J. Entomol. 104 (2): 347-349, 2007 | DOI: 10.14411/eje.2007.050

There is a high density of the cicada Cryptotympana facialis (Walker) (Hemiptera: Cicadidae) in urban parks in central Japan during summer. This cicada uses its stylet to pierce holes in the trunks of keyaki trees, Zelkova serrata and then feeds on the exuding xylem sap. Three ant species, Formica japonica Motschulsky, Lasius japonicus Santschi and Crematogaster matsumurai Forel (Hymenoptera: Formicidae) were observed aggregatively feeding on these exudates. In addition, two wasp species, Polistes jokohamae Radoszkowski (Hymenoptera: Vespidae), and Ampulex dissector (Thunberg) (Hymenoptera: Sphecidae) fed on the sap. These ants and wasps can therefore be classified as commensals. Two flower chafers, Protaetia brevitarsis (Lewis) and P. orientalis submarumorea (Burmeister) (Coleoptera: Scarabaeidae) were also observed displacing cicadas from their feeding sites and feeding on the exuding sap. Thus, these chafers can be classified as both commensals and kleptoparasites.

Temporal effects of multiple mating on components of fitness in the two-spot ladybird, Adalia bipunctata (Coleoptera: Coccinellidae)

Penelope R. HADDRILL, David M. SHUKER, Sean MAYES, Michael E.N. MAJERUS

Eur. J. Entomol. 104 (3): 393-398, 2007 | DOI: 10.14411/eje.2007.058

Insects have provided much of the best evidence to date concerning possible costs and benefits of multiple mating, and here we investigate the benefits of polyandry in the two-spot ladybird, Adalia bipunctata, by attempting to replicate the highly promiscuous mating system in this species. We compared the temporal pattern of reproductive success of females mated multiple times to one male with that of females mated an equal number of times to multiple males, and found transient differences in offspring production and hatch rate over time. Our data suggest that polyandrous females benefit from multiple mating in some circumstances, but the patterns are complex. Following how both the costs and benefits to mating accrue over time will be necessary if we are to fully understand why polyandry evolves.

An Erratum has been published for this article: https://doi.org/10.14411/eje.2010.054

BOOK REVIEW: Podenas S., Geiger W., Haenni J.-P. & Gonseth Y. 2006: Limoniidae & Pediciidae de Suisse. In: FAUNA HELVETICA. Vol. 14.

J. STARÝ

Eur. J. Entomol. 104 (2): 350, 2007 | DOI: 10.14411/eje.2007.051

Centre suisse de cartographie de la faune & Schweizerische Entomologische Gesellschaft, Neuchâtel, 375 pp. ISBN 2-88414-026-3. Price CHF 56.00.

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