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42. Periods of dormancy and cohort-splitting in the millipede Polydesmus angustus (Diplopoda: Polydesmidae)
- Creator:
- David, Jean-François, Celerier, Marie-Louise, and Geoffroy, Jean-Jacques
- Format:
- print, text, and regular print
- Type:
- article, bibliography, conference publication, model:article, and TEXT
- Subject:
- Third European Workshop of Invertebrate Ecophysiology (1998 : Birmingham, Česko), zoologie, fyziologie živočichů, ekofyziologie, hmyz, Diplopoda, Polydesmus angustus, životní cyklus, reprodukční dormance, diapauza, sezónní vlivy, 591.5, 061.3, and 595.2/.7
- Language:
- English
- Description:
- First stadium juveniles of P. angustus were reared under controlled seasonal conditions to maturity, reproduction and death. Individuals born in any one breeding season either had a 1-year or a 2-year life cycle (cohort-splitting). The life cycle was annual for individuals born in the first part of the breeding season (May-August), but became biennial for those born later (August-October). Two phenomena were involved: (1) Only individuals reaching the penultimate stadium (stadium VII) before a critical period at the end of spring could become adult in the breeding season following that of their birth. After this time, stadium VII individuals entered into aestivation and only became adult in the second autumn after their birth. (2) Females becoming adult in autumn entered reproductive dormancy and only laid eggs in the following spring. Overall, individuals born at the start of the breeding season easily reached stadium VII before the critical period and were able to breed at I year, whereas individuals born at the end of the breeding season reached stadium VII after the critical period, then had two consecutive periods of dormancy and only bred at 2 years age. Individuals from the same nest born in the middle of the breeding season (August) could have either annual or biennial life cycles, depending on whether they reached stadium VII before or during aestivation. The environmental factors capable of triggering aestivation in subadults and reproductive dormancy in autumn-maturing females are discussed., Jean-Francois David, Marie-Louise Celerier, Jean-Jacques Geoffroy, and Lit
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
43. Phylogeny of endopterygote insects, the most successful lineage of living organisms
- Creator:
- Kristensen, Niels P.
- Format:
- print, text, and regular print
- Type:
- article, bibliography, model:article, and TEXT
- Subject:
- zoologie, hmyz, Endopterygota, Holometabola, fylogeneze, 595.2/.7, and 591.3
- Language:
- English
- Description:
- The monophyly of the Endopterygota is supported primarily by the specialized larva without external wing buds and with degradable eyes, as well as by the quiescence of the last immature (pupal) stage; a specialized morphology of the latter is not an endopterygote groundplan trait. There is weak support for the basal endopterygote splitting event being between a Neuropterida + Coleoptera clade and a Mecopterida + Hymenoptera clade; a fully sclerotized sitophore plate in the adult is a newly recognized possible groundplan autapomorphy of the latter. The molecular evidence for a Strepsiptera + Diptera clade is differently interpreted by advocates of parsimony and maximum likelihood analyses of sequence data, and the morphological evidence for the monophyly of this clade is ambiguous. The basal diversification patterns within the principal endopterygote clades (\"orders\") are succinctly reviewed. The truly species-rich clades are almost consistently quite subordinate. The identification of \"key innovations\" promoting evolutionary success (in terms of large species numbers) is fraught with difficulties., Niels P. Kristensen, and Lit
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
44. Plumbagin and azadirachtin deplete hemolymph ecdysteroid levels and alter the activity profiles of two lysosomal enzymes in the fat body of Helicoverpa armigera (Lepidoptera: Noctuidae)
- Creator:
- Josephrajkumar, Arulappan, Subrahmanyam, Bhattiprolu, and Srinivasan, S.
- Format:
- print, text, and regular print
- Type:
- article, bibliography, model:article, and TEXT
- Subject:
- zoologie, entomologie, hmyz, fyziologie hmyzu, motýli, Noctuidae, Helicoverpa armigera, metamorfóza, růstové regulátory, plumbagin, azadirachtin, účinky, ekdysteroid, kyselá fosfatáza, beta-galaktosidáza, morfologické abnormality, 591.1, and 595.2/.7
- Language:
- English
- Description:
- The profile of hemolymph ecdysteroid was studied in the gram pod borer, Helicoverpa armigera, during larval-pupal transformation. The changes closely correspond to the developmental events occurring at metamorphosis. Two insect growth regulators, plumbagin and azadirachtin, significantly depleted the content and altered the profile of ecdysteroids at crucial stages, when applied at ED50 doses. The activity profiles of two fat body lysosomal enzymes, acid phosphatase and b-galactosidase, were also significantly affected by the insect growth regulators. It is suggested that plumbagin and azadirachtin treatments primarily modify the ecdysteroid titer, which in turn leads to changes in lysosomal enzyme activity causing overt morphological abnormalities during the metamorphic molt., Arulappan Josephrajkumar, Bhattiprolu Subrahmanyam, Srinivasan, and Lit
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
45. Revision of the genus Macroscytus (Heteroptera: Cydnidae) in Madagascar and adjacent islands, with description of four new species
- Creator:
- Lis, Jerzy A.
- Format:
- print, text, and regular print
- Type:
- article, bibliography, model:article, and TEXT
- Subject:
- zoologie, entomologie, hmyz, ploštice, Cydnidae, Macroscytus, taxonomická revize, nové druhy, popis, Madagaskar, and 595.2/.7
- Language:
- English
- Description:
- A revision of species of the genus Macroscytus Fieber distributed in Madagascar and adjacent islands is presented. Four previously known species [M. fryeri Distant, M. lobatus Signoret, M. madagascariensis (Signoret), M. privignus Horváth] are redescribed, and lectotypes are designated for three of them. Four new species (M. mayottensis sp. n., M. simulans sp. n., M. tamatavei sp. n., and M. viettei sp. n.) are described and compared with their congeners. A key to all species of the genus known from Madagascar and adjacent islands is also provided., Jerzy A. Lis, and Lit
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
46. Site latitude influences on respiration rate, fat content and the ability of worker ants to rear larvae: A comparison of Myrmica rubra (Hymenoptera: Formicidae) populations over their European range
- Creator:
- Elmes, Graham W., Radchenko, Alexander G., Barr, Boyd, Wardlaw, Judith C., Nielsen, Mogens G., Kipyatkov, Vladilen E., and Lopatina, Elena B.
- Format:
- print, text, and regular print
- Type:
- article, bibliography, conference publication, model:article, and TEXT
- Subject:
- zoologie, fyziologie živočichů, ekofyziologie, hmyz, mravenci, Myrmica rubra, dýchání, obsah tuku, péče o larvy, hranice rozšíření, vliv zeměpisné polohy, 591.5, 061.3, and 595.2/.7
- Language:
- English
- Description:
- Myrmica rubra is a northern, temperate Palaearctic ant species with a geographical range that extends from the Atlantic coast of Europe to central Asia. In Europe, its range covers > 25° of latitude where it lives under a variety of climates that vary from extreme oceanic in the west, to continental in the east. Colonies nest in the soil and their life cycles are known to be highly dependent on ambient temperature and soil moisture. We hypothesised that the brood-rearing behaviour of populations might be focally adapted to climate and that we might detect differences when the ants were reared under \"common-garden\" conditions. Brood-rearing behaviour was compared for 38 colonies of M. rubra drawn from 13 populations representing a range of 6 latitudes: all 6 were represented in eastern Europe and 2 in western Europe. A sample of ants from each colony was used to estimate respiration rate, body mass and fat content at the start of the experiment in spring (immediately post hibernation) and at the end of the experiment (mid summer). Respiration had a linear relationship with latitude, with northern populations having greater respiration rate in spring compared to southern populations. It is suggested that this is an adaptation to different seasonality over the species' range that results in the \"more active\" northern workers rearing fewer brood to maturity more quickly than southern workers. Fat content, a measure of worker \"quality\", had a parabolic relationship with latitude with mid latitude colonies having the fattest workers. Fatter workers appeared to rear heavier brood. This probably represented a functional response to environment with populations living at \"edge of range\" sites being physiologically more stressed and performing brood-rearing tasks less well than centre of range populations. We believe that this is the first demonstration of a consistent, intra-specific trend for Variation in the social physiology of an ant species over its geographic range., Graham W. Elmes, Judith C. Wardlaw, Mogens G. Nielsen, Vladilen E. Kipyatko, Elena B. Lopatina, Alexander G. Radchenko, Boyd Barr, and Lit
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
47. Species at the edge of their range: The significance of the thermal environment for the distribution of congeneric Craspedolepta species (Sternorrhyncha: Psylloidea) living on Chamerion angustifolium (Onagraceae)
- Creator:
- Bird, Jeremy M. and Hodkinson, Ian D.
- Format:
- print, text, and regular print
- Type:
- article, bibliography, conference publication, model:article, and TEXT
- Subject:
- Third European Workshop of Invertebrate Ecophysiology (1998 : Birmingham, Česko), zoologie, fyziologie živočichů, ekofyziologie, hmyz, Psylloidea, Craspedolepta nebulosa, Craspedolepta subpunctata, výskyt, rozšíření, životní cyklus, fenologie, ekologické faktory, teplota, sezónní vlivy, 591.5, 061.3, and 595.2/.7
- Language:
- English
- Description:
- There is much current discussion about the factors that control the distribution and abundance of animal species, particularly at the edges of their range. The significance of temperature for survival and development is compared in two closely related psyllid species (Craspedolepta nebulosa and C. subpunctata) living on the same host plant (Chamerion angustifolium) (Onagraceae) but displaying different distributions along latitudinal and altitudinal gradients. The following measurements were made at critical periods during the life cycle (a) winter supercooling points (SCPs), (b) tolerance of short (1 min) and long term (1-25) days exposure to sub-zero temperatures above the SCP, (c) tolerance of short term exposure to high spring/summer temperatures and (d) comparative field development rates among species and sites during the early critical part of the growing season. Successful completion of the life cycle is related to heat availability during the growing season. This appears to limit the distribution of the Craspedolepta species, rather than their survival response to thermal extremes. No significant differences were found between the two species in the supercooling point or in their long and short term survival responses at low or high temperatures., Jeremy M. Bird, Ian D. Hodkinson, and Lit
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
48. Stimulation of locomotion in Pyrrhocoris apterus (Heteroptera: Pyrrhocoridae) is wing-morph independent and correlated with lipid mobilization by adipokinetic hormone
- Creator:
- Socha, Radomír, Kodrík, Dalibor, and Zemek, Rostislav
- Format:
- print, text, and regular print
- Type:
- article, bibliography, model:article, and TEXT
- Subject:
- zoologie, entomologie, hmyz, ploštice, Pyrrhocoridae, Pyrrhocoris apterus, dospělé samičky, diapauza, tuky, mobilizace lipidů, pohyb lipidů, adipokinetické hormony, stimulační účinky, 595.2/.7, and 591.1
- Language:
- English
- Description:
- The effects of 5 pmols of adipokinetic hormone (Lom-AKH-I) on both the locomotion and mobilization of lipids were studied in 10-day-old diapausing adult females of the short-winged (brachypterous) morph of Pyrrhocoris apterus (L.). The results revealed that AKH stimulation of locomotion in this bug is wing-morph independent. The stimulatory effect of AKH on locomotion was shown to be positively correlated with its effect on lipid mobilization., Radomír Socha, Dalibor Kodrík, Rostislav Zemek, and Lit
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
49. Structure elucidation of Mas-AKH as the major adipokinetic hormone in the butterfly Vanessa cardui (Lepidoptera: Nymphalidae)
- Creator:
- Gäde, Gerd, Hoffmann, Klaus H., Köllisch, Gabriele, Verhaert, Peter D., Lorenz, Matthias W., and Kellner, Roland
- Format:
- print, text, and regular print
- Type:
- article, bibliography, model:article, and TEXT
- Subject:
- zoologie, entomologie, hmyz, motýli, Nymphalidae, Vanessa cardui, corpora cardiaca, adipokinetické hormony, struktura, peptidické složení, hmotnostní spektrometrie, 595.2/.7, and 591.1
- Language:
- English
- Description:
- The presence of adipokinetic activity in crude extracts of corpora cardiaca (CC) from the butterfly (Vanessa cardui L., Nymphalidae) was demonstrated by bioassay and Mas-AKH was revealed as the major adipokinetic hormone (AKH) by use of two different technologies of sequence elucidation: HPLC separation of the peptide followed by Edman degradation and Q-TOF mass spectrometry. In contrast to the time- and material-consuming conventional methods of peptide purification and sequencing, substantial structural data of the peptide were confirmed - post factum - from one pCC (pair of CC) by Q-TOF mass spectrometry. Only males of our laboratory colony showed a significant lipid increase in the haemolymph after injection of either crude CC extract (1 pCC equivalent) or 10 pmol of synthetic peptide., Gabriele Köllisch, Peter D. Verhaert, Matthias W. Lorenz, Roland Kellner, Gerd Gäde, Klaus H. Hoffmann, and Lit
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
50. Studien über die Entwicklung der apterygoten Insecten
- Creator:
- Jindřich Uzel
- Publisher:
- J. Uzel
- Format:
- print, text, regular print, and v, 58 s., 6 l. obr. příl. : il. ; 34 cm
- Type:
- model:monograph and TEXT
- Subject:
- Obecná zoologie, hmyz, vývojová stadia živočichů, bezkřídlí, 595.7, 591.31/.36, (048.8), 2, and 591
- Language:
- German
- Description:
- von Heinrich Uzel
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public