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142. Co je nového v zoologii. Pozor na šakala!
- Creator:
- Miloš Anděra
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, zoologie, savci, mammals, 2, and 59
- Language:
- Czech
- Description:
- Šakal obecný (Canis aureus) je nový druh fauny savců České republiky. Na naše území se přirozenou cestou rozšířil z jihovýchodní Evropy. První věrohodný doklad pochází z Uherského Hradiště (2006), další pak z Brna (2009) a z Benešovska (střední Čechy, 2011). Řada dalších neověřených pozorování i nálezy z příhraničních oblastí Šumavy naznačují, že expanze druhu pokračuje., The Golden Jackal (Canis aureus) is a quite new member of the fauna of the Czech Republic. So far, three verified records in the environs of Uherské Hradiště (2006), Brno (2009) and Benešov (Central Bohemia, 2011) have been obtained. A number of other unverified observations and findings from the border areas of the Šumava Mountains (Bohemian Forest) suggest that the expansion of the species is ongoing., Miloš Anděra., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
143. Co je za přemnožováním (gradací) lýkožrouta smrkového na Šumavě
- Creator:
- Pavel Kindlmann, Karel Matějka, and Petr Doležal
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, lýkožrout smrkový, smrk, Šumava (pohoří), 2, and 59
- Language:
- Czech
- Description:
- During summer 2011, severe outbreak of the Spruce Bark Beetle (Ips typographus) occurred in the Šumava National Park (NP). We aim to elucidate the laws governing population dynamics of this species and conclude that logging of all infested trees in the NP buffer zones, accompanied by a non-intervention policy in the core zones, is a strategy that will protect both, forests surrounding the NP and the most valuable mountain spruce stands in the Šumava NP. and Pavel Kindlmann, Karel Matějka, Petr Doležal.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
144. Co-occurrence of host plants associated with plant quality determines performance patterns of the specialist butterfly, Battus polydamas archidamas (Lepidoptera: Papilionidae: Troidini)
- Creator:
- Rios, Rodrigo S., Salgado-Luarte, Cristian, Stotz, Gisela C., and Gianoli, Ernesto
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, motýli, otakárkovití, butterflies, Papilionidae, Lepidoptera, Troidini, Battus polydamas archidamas, Aristolochia, polydamas swallowtail, larval performance on host plants, host plant-induced preference, performance mosaic, plant quality, 2, and 59
- Language:
- English
- Description:
- In herbivorous insects, differences in the degree of specialization to host plants emerge when the distribution of an herbivore differs from that of its host plants, which results in a mosaic of populations differing in performance on the different host plants. Using a specialized butterfly, Battus polydamas archidamas Boisduval, 1936, which feeds exclusively on the genus Aristolochia, we test whether host plant co-occurrence and associated differences in host quality modify local adaptation in terms of larval preference and performance. We compared individuals from a monospecific host stand of Aristolochia chilensis with those from a mixed host stand of A. chilensis and A. bridgesii. Individuals were reared in a reciprocal transfer experiment in which source population and the host species fed to larvae were fully crossed in a two-by-two factorial experiment in order to quantify their preference, performance (development time, size and growth rate) and survival. Individuals from both populations preferred the species they ate during their larval development over the other host, which indicates host plant-induced preference with non-adaptive implications. Larvae from mixed and monospecific stands grew faster and survived better when reared on A. bridgesii than A. chilensis. Larvae from a monospecific host stand grew slower and fewer individuals survived under the same local conditions, which is contrary to expectations. Therefore, rearing the butterfly on A. bridgesii consistently resulted in better performance, which indicates that the monospecific population is less well adapted to its host than the mixed population. Variation in the occurrence of the two host plants in the two populations can result in divergent selection due to the variation in plant quality, which in this case could result in opposing adaptive processes., Rodrigo S. Rios, Cristian Salgado-Luarte, Gisela C. Stotz, Ernesto Gianoli., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
145. Coccinellidae captured in blacklight traps: seasonal and diel pattern of the dominant species Harmonia axyridis (Coleoptera: Coccinellidae)
- Creator:
- Christine A. Nalepa
- Type:
- article, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Coleoptera, Coccinellidae, Harmonia axyridis, Coleomegilla maculata, Hippodamia convergens, Coccinella septempunctata, blacklight trap, ultraviolet, migration, phototaxis, flight-oogenesis, nocturnal, 2, and 59
- Language:
- English
- Description:
- Two blacklight traps were operated in a non-agricultural setting in Cary, North Carolina, USA, from spring through fall in 2004 and 2005 and all Coccinellidae collected and identified. More than 1300 lady beetles were collected in each of the two years, with Harmonia axyridis dominant (> 98%) and collected consistently over the course of the trapping period. Although other coccinellid species were observed in the vicinity of the traps during photophase, their appearance in blacklight traps was negligible. Harmonia axyridis exhibited a distinct diel periodicity in appearance at the traps, beginning approximately an hour after sunset and ending about midnight. Sunrise and sunset collections from flight interference and sticky traps in a local alfalfa field suggest that H. axyridis may be more flight active during the scotophase than Coleomegilla maculata, Hippodamia convergens, and Coccinella septempunctata. This study supports the suggestion that blacklight traps give a biased depiction of coccinellid species composition in a given area, and indicates that seasonal and circadian thresholds for flight activity, phototaxis, or both in H. axyridis may diverge from those in most other Coccinellidae., Christine A. Nalepa., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
146. Cohort-splitting in the millipede Polydesmus angustus (Diplopoda: Polydesmidae): No evidence for maternal effects on life-cycle duration
- Creator:
- David, Jean-François and Geoffroy, Jean-Jacques
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, Diplopoda, Polydesmus angustus, life cycle, development time, diapause, maternal effect, bet-hedging, 2, and 59
- Language:
- English
- Description:
- Under seasonal conditions, Polydesmus angustus individuals born in the first part of the breeding season have a 1-year life cycle and those born later have a 2-year life cycle (cohort-splitting). In this study, 249 juveniles from four early broods (born in mid-July) and four late broods (born in September) were reared under similar laboratory conditions, to test for possible maternal influences on life-cycle duration. Development times of early- and late-born individuals were compared under four combinations of day length and temperature (16 h - 18°C, 16 h - 16°C, 12 h - 18°C and 12 h - 16°C). The results showed that development time varied significantly in response to day length, temperature and sex, but that of individuals in the early and late broods did not differ significantly (mean development times ± SE: 180 ± 6 and 183 ± 8 days, respectively). There were no significant interactions between birth period and other factors, indicating that the effects of day length, temperature and sex on development time were similar in early- and late-born individuals. This indicates that the extended life cycle of millipedes born late in the season is not maternally determined and that cohort-splitting is controlled entirely by the environmental conditions experienced by the offspring during their development. This conclusion is supported by the absence of significant variation in offspring live weight at birth measured at different times in the breeding season. The results are discussed in relation to the bet-hedging theory, which is often put forward to account for cohort-splitting in arthropods. In P. angustus, the results are consistent with either bet-hedging or adaptive plasticity, but further studies are required to decide which interpretation is correct. and Jean-François David, Jean-Jacques Geoffroy.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
147. Cold hardiness of larvae of Dendrolimus tabulaeformis (Lepidoptera: Lasiocampidae) at different stages during the overwintering period
- Creator:
- Shao, Yuying, Feng, Yuqian, Tian, Bin, Wang, Tao, He, Yinghao, and Zong, Shixiang
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- motýli, larvy, butterflies, larvas, Lepidoptera, Lasiocampidae, Dendrolimus tabulaeformis, supercooling point, cryoprotectants, cold hardiness, 2, and 59
- Language:
- English
- Description:
- The Chinese pine caterpillar Dendrolimus tabulaeformis is an important destructive leaf borer in boreal coniferous forests in China. This species overwinters in the larval stage. Changes in supercooling capacity and physiological-biochemical parameters of D. tabulaeformis larvae from a natural population were evaluated at different stages during the overwintering period. Cold hardiness of overwintering larvae collected in January was significantly greater than that of larvae collected in other months. January larvae survived for 15 days at -10°C and for approximately 2 days at -15°C. By contrast, larvae collected in September survived for no more than 4 h at -5°C and those in November and March no more than 1 day at -15°C. Supercooling point gradually decreased from -5.9 ± 0.3°C in September to a minimum of -14.1 ± 1.0°C in November, then gradually increased to the original value with the advent of spring. Water content gradually decreased from September to November, remained at approximately 74.5% until March and then gradually increased to levels similar to those in September. The lipid content gradually decreased from September to November, remained stable at approximately 3.2% until March and then gradually increased to levels similar to those in September. Glycogen content increased to a peak in November and then decreased. The concentrations of several metabolites showed significant seasonal changes. The most prominent metabolite was trehalose with a seasonal maximum in November. Glucose levels were highest in January and then gradually decreased until in May they were at levels similar to those in September. Glycerol levels remained relatively stable during winter but increased significantly in May. This study indicates that D. tabulaeformis is a freeze-avoidant insect. Larvae increase their supercooling capacity by regulating physiological-biochemical parameters during overwintering., Yuying Shao, Yuqian Feng, Bin Tian, Tao Wang, Yinghao He, Shixiang Zong., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
148. Cold storage affects mortality, body mass, lifespan, reproduction and flight capacity of Praon volucre (Hymenoptera: Braconidae)
- Creator:
- Lins Jr, Juracy Caldeira, Bueno, Vanda Helena Paes, Sidney, Livia Alvarenga, Silva, Diego Bastos, Sampaio, Marcus Vinicius, Pereira, Janser Moura, Nomeliny, Quintiliano Siqueira Schroden, and Van Lenteren, Joop C.
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Hymenoptera, Braconidae, Praon volucre, biological control, storage, Macrosiphum euphorbiae, 2, and 59
- Language:
- English
- Description:
- The possibility of storing natural enemies at low temperatures is important for the mass production of biological control agents. We evaluated the effect of different periods of cold storage on immature mortality, mummy body mass, lifespan, reproduction and flight capacity of the parasitoid Praon volucre (Haliday). One-day-old mummies of the aphid Macrosiphum euphorbiae (Thomas) containing pre-pupae of P. volucre were stored in a climatic chamber at 5°C and 70 ± 10% RH in the dark for different periods of time (5, 10, 15 and 20 days). The control consisted of mummies kept at 22 ± 1°C, 70 ± 10% RH and a 12 h photophase. Percentage adult emergence, mummy body mass, flight capacity and number of eggs in the ovarioles of P. volucre females decreased with increase in the period of storage, while the longevity of females was only slightly affected. Fat content of mummies, percentage of parasitized aphids and survival of progeny to emergence decreased with increase in the period of storage. Storage of P. volucre pre-pupae for up to 5 days at 5°C did not affect any of the above mentioned parameters. The fact that P. volucre pre-pupae can be stored for 5 days without loss of quality and for 10 days with only a slight loss facilitates the planning of mass production and shipment., Juracy Caldeira Lins, Jr. ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
149. Comparative analysis of maternal and grand-maternal photoperiodic responses of Trichogramma species (Hymenoptera: Trichogrammatidae)
- Creator:
- Voinovich, Natalia D., Vaghina, Nina P., and Reznik, Sergey Ya.
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Hymenoptera, Trichogrammatidae, Trichogramma, diapause, photoperiod, temperature, maternal effect, grand-maternal effect, comulative photoperiodic effect, 2, and 59
- Language:
- English
- Description:
- 1_Maternal and grand-maternal photoperiodic responses of Trichogramma buesi, T. embryophagum, T. evanescens, T. piceum, T. principium, and T. telengai were investigated in laboratory conditions. During the experiment, grand-maternal and maternal generations developed at 20°C and one of the 4 photoperiodic regimes: L : D = 12 : 12, 14 : 10, 16 : 8, and 18 : 6 (in total, 16 combinations) while the progeny developed at L : D = 12 : 12 and one of the 3 thermal regimes: 13, 14, and 15°C. The proportion of diapausing individuals in the progeny of all the studied species was significantly dependent on the direct influence of temperature and on the maternal photoperiodic response. The influence of the photoperiodic conditions during development of the grand-maternal generation was statistically significant in 5 of the 6 studied species, being relatively weak in T. embryophagum and T. telengai, whose geographical ranges extend up to north-western regions of Europe (possibly, these wasps enter diapause so early that the grand-mothers of the diapausing generation develop under long day conditions). Comparative analysis showed that the thresholds of the maternal and grand-maternal photoperiodic responses coincided or almost coincided. The grand-maternal effect was stronger in the progeny of maternal females which developed under short day conditions than in those that developed under long day conditions. This pattern of interaction probably synchronizes the life cycle with seasonal changes because diapause is induced under decreasing day length and thus mothers of diapausing individuals develop at shorter daylength than do grand-mothers., 2_We conclude that the grand-maternal and the maternal effects on Trichogramma progeny diapause are based on one and the same photoperiodic response. In nature, the grand-maternal effect increases the proportion of diapausing individuals in the progeny of females which have developed under short day conditions during two generations, thus achieving a "cumulative" photoperiodic effect., Natalia D. Voinovich, Nina P. Vaghina, Sergey Ya. Reznik., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
150. Comparative analysis of the location of rDNA in the Palaearctic bushcricket genus Isophya (Orthoptera: Tettigoniidae: Phaneropterinae)
- Creator:
- Grzywacz, Beata, Maryańska-Nadachowska, Anna, Chobanov, Dragan P., Karamysheva, Tatjana, and Warchałowska-Śliwa, Elżbieta
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, Orthoptera, FISH, Ag-NOR, rDNA, telomeric repeats, 2, and 59
- Language:
- English
- Description:
- The present study focused on the evolution of the karyotype in 21 taxa of the genus Isophya, which was done by mapping the location on the chromosomes of ribosomal RNA (rRNA) coding genes using fluorescence in situ hybridization (FISH) with an 18S rDNA probe and using silver staining (AgNO3) to evaluate the activity of major rDNA clusters. Since the chromosome number and sex determination do not vary in this genus, the above markers were used in a detailed comparison of the cytogenetic features of species of Isophya. The species analyzed were placed into three groups based on the location of rDNA on their chromosomes: (1) rDNA-FISH signals only on the two long pairs of autosomes, (2) rDNA-FISH signals on one long and one short pair of autosomes, and (3) rDNA-FISH signals on three to five different sized pairs of autosomes. These groupings partly correspond to the morphological groupings proposed in earlier studies. One long pair of autosomes frequently carried rDNA in all the Isophya species and probably is a plesiomorphic character for these taxa. The cytogenetic mapping revealed great variability among Isophya species in the chromosomal location of major rDNA clusters. Our results suggest that the observed variation in the number of rDNA clusters can be an important species-group specific phylogenetic marker. Analysis of 18S rDNA hybridization signals showed that the evolutionary dynamics of rDNA in this genus is remarkably high and accompanied by changes in the structure of chromosomes bearing rDNA at an inter- and intra-specific level. The telomeric sequence (TTAGG)n hybridized with the termini of most of chromosomes, however, some chromosome ends lacked signals probably due to a low copy number of telomeric repeats. and Beata Grzywacz, Anna Maryańska-Nadachowska, Dragan P. Chobanov, Tatjana Karamysheva, Elżbieta Warchałowska-Śliwa.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public