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631. Variation in the colour of the necrophagous fly, Prochyliza nigrimana (Diptera: Piophilidae): A case of seasonal polymorphism

Creator:
Martín-Vega, Daniel and Baz, Arturo
Type:
article, články, model:article, and TEXT
Subject:
Zoologie, entomologie, melanism, seasonal polymorphism, Piophilidae, Prochyliza nigrimana, 2, and 59
Language:
English
Description:
The occurrence of colour polymorphism in wild populations of the necrophagous fly Prochyliza nigrimana (Diptera: Piophilidae) is recorded but never treated in detail. The present paper shows that there is a seasonal distribution in the morphotypes, with the dark morphs emerging in spring and pale morphs emerging later and most abundant in summer. Furthermore, different proportions of each morph occur along altitudinal gradients, with dark morphs significantly more abundant at low altitudes, where mean temperatures are warmer than at high altitudes where the pale coloured morphs were more abundant. Explanations based on the adaptive value of thermal melanism are discussed. and Daniel Martín-Vega, Arturo Baz.
Rights:
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632. Variation of thorax flight temperature among twenty Australian butterflies (Lepidoptera: Papilionidae, Nymphalidae, Pieridae, Hesperiidae, Lycaenidae)

Creator:
Nève, Gabriel and Hall, Casey
Format:
print, počítač, and online zdroj
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Zoologie, otakárkovití, babočkovití, běláskovití, motýli, Papilionidae, Nymphalidae, Pieridae, butterflies, Lepidoptera, Hesperiidae, Lycaenidae, thorax flight temperature, wing loading, infra red thermometer, warming-up rate, physical constraint, allometry, 2, and 59
Language:
English
Description:
Thermal requirements for flight in butterflies is determined by a combination of external factors, behaviour and physical constraints. Thorax temperature of 152 butterflies was monitored with an infra-red thermometer in controlled laboratory conditions. The temperature at take-off varied from 13.4°C, for a female Heteronympha merope to 46.3°C, for a female Junonia villida. Heteronympha merope, an understorey species, had the lowest recorded take-off temperatures, with females flying at a much lower thorax temperatures than males. Among the tested butterfly species, warming-up rate was positively correlated with take-off temperature and negatively with body mass. Wing loading is a major variable in determining the thorax flight temperature. Butterflies with the highest wing-loadings experienced the highest thorax temperatures at take-off. A notable exception to this rule is Trapezites symmomus, the only Hesperiidae of our data set, which had thorax flight temperatures of 31.5°C and 34.5°C, well within the range of the observed butterflies, despite a wing load ca. five times higher. The high thorax temperature recorded in J. villida is probably linked to its high flight speed. The results highlight the importance of physical constraints such as body size on the thermal requirements for flight across a range of butterfly species., Gabriel Nève, Casey Hall., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

633. Variations in the ultrastructure of the flight muscles of the polymorphic cricket, Gryllus firmus (Orthoptera: Gryllidae)

Creator:
Jiang, Cheng-Ji, Zhang, Bao-Chang, Chen, Wen-Feng, Zhang, Qing-Wen, Zhao, Zhang-Wu, An, Chun-Ju, and Li, Jie-Ping
Type:
article, články, model:article, and TEXT
Subject:
Zoologie, zoologie, entomologie, Orthoptera, Gryllidae, Gryllus firmus, flight muscle, ultrastructure, juvenile hormone, Transmission Electron, Microscope, 2, and 59
Language:
English
Description:
Although there is a considerable amount of information on the ecology, genetics and physiology of life-history traits there is little information on the morphological variations associated with flight ability within species. In this paper, the morphology and ultrastructure of certain organelles in the flight muscles of Gryllus firmus are recorded using transmission electron microscopy. The ultrastructure of the flight muscles of 7-day-old female adults reveals that the ratio of thick to thin filaments is 1 : 3. Each thick filament is surrounded by 6 thin filaments in a hexagonal arrangement. The length of the sarcomere of each myofibril is significantly shorter and diameter of the myofibrils significantly smaller in long-winged than in short-winged morphs. However, the thick filaments in the long-winged morph are denser than those in the short-winged morph. Furthermore, in the long winged morph there are a greater number of mitochondria than in the short-winged morph. These differences correspond with the fact that long-winged crickets are stronger fliers than short-winged crickets., Cheng-Ji Jiang ... [et al.]., and Obsahuje seznam literatury
Rights:
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634. Včelínka ozdobná - další z úspěšných výsadků alpského původu - z červené knihy našich měkkýšů

Creator:
Lacina, Adam and Michal Horsák
Format:
print
Type:
article, články, model:article, and TEXT
Subject:
Zoologie, měkkýši, malakologie, Česko, 2, and 59
Language:
Czech
Description:
During the last 12 years, 23 mollusc species were recorded in the Czech Republic for the first time. With the exception of several introduced and invasive species, some of these molluscs are native, rare and even endangered, including Pagodulina pagodula. This rare woodland snail of Alpine origin was found in spring 2012 in the Mutenská obora Nature Reserve, which includes the forested slopes above the Moravská Dyje River in South Moravia. This is another occurrence of the species outside its Alpine range, in addition to one site in Poland, two in Slovakia, and a few sites in Hungary and the Balkan Peninsula. The species was also recorded in the Czech Republic in several interglacial sediments of the Pleistocene and also in one profile of Holocene origin (Atlantic period), not far away from the recent site. and Adam Lacina, Michal Horsák.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

635. Věda je krásná - V. ročník soutěže s přírodovědnou tematikou

Creator:
Alena Ječmíková
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Zoologie, zoologie, soutěže, přírodověda, 2, and 59
Language:
Czech
Description:
Soutěžní přehlídka Věda je krásná vznikla v r. 2009 jako interní fotografická soutěž Přírodovědecké fakulty Univerzity Karlovy v Praze. Od třetího ročníku je přístupná všem zaměstnancům a studentům Univerzity Karlovy a ve čtvrtém ročníku se v nové objevitelské kategorii otevřela mimofakultní veřejnosti, která se jí může účastnit prostřednictvím popularizačního projektu Přírodovědci.cz. Cíl projektu je velmi jednoduchý - oslavit českou fotografii a ilustraci s přírodovědnou tematikou a upozornit na krásu skrytou běžnému pohledu, tedy na půvab vědeckých objektů a vědy samotné, protože zůstávají často přístupné jen úzkému okruhu badatelů nebo nadšenců., This competition run by the Faculty of Science at Charles University in Prague and its supportive web www.prirodovedci.cz aims to show the beauty and aesthetics revealed by scientific research, either via photography, illustrations or computerized visualizations of natural phenomena., and Alena Ječmíková.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

636. Velemyš dinagatská - znovuobjevení a nové české jméno domněle vyhynulého hlodavce =

Creator:
Řeháková, Milada and Řehák, Václav
Format:
print
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Zoologie, savci, myšovití, vyhynulé druhy, Filipíny, Philippines, 2, and 59
Language:
Czech
Description:
Velemyši, dříve nazývané krysy obláčkové, jsou největší myšovití hlodavci žijící endemicky na Filipínách. Velemyš dinagatskou (Crateromys australis), považovanou za potenciálně vyhynulou, se nám podařilo znovuobjevit 37 let od jejího posledního (a zároveň prvního) nálezu a vědeckého popisu. To bylo také impulzem k návrhu nového českého jména velemyši pro celou skupinu obláčkových krys. Velemyš dinagatská byla nalezena na severu ostrova Dinagat. Nyní je řazena mezi kriticky ohrožené druhy. Ohrožené jsou také ostatní druhy této skupiny, a to zejména kvůli masivní těžbě dřeva a nerostných surovin a tím ničením jejich přirozeného prostředí. Proto je cílená ochrana je nezbytná k přežití tohoto i ostatních druhů velemyší., Cloud rats are the largest murid rodents endemic to the Philippines. The Dinagat Cloud Rat (Crateromys australis), considered to be potentially extinct, was rediscovered in the north of Dinagat Island after 37 years from its first discovery and scientific description. We have also proposed a new Czech name. The species is now listed as critically endangered. All cloud rats are threatened by the destruction of their natural habitats by logging and mining. Targeted protection is therefore essential for their survival., and Milada Řeháková, Václav Řehák.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

640. Vertical stratification and microhabitat selection by the Great Capricorn Beetle (Cerambyx cerdo) (Coleoptera: Cerambycidae) in open-grown, veteran oaks

Creator:
Albert, Jan, Platek, Michal, and Cizek, Lukas
Type:
article, články, model:article, and TEXT
Subject:
Zoologie, zoologie, entomologie, Cerambycidae, Cerambyx cerdo, dead wood, NATURA 2000, Quercus, saproxylic, longhorned beetle, xylophagous, woodland, 2, and 59
Language:
English
Description:
The great capricorn beetle or Cerambyx longicorn (Cerambyx cerdo, Linnaeus, 1758) is an internationally protected umbrella species representing the highly diverse and endangered fauna associated with senescent oaks. For the conservation and monitoring of populations of C. cerdo it is important to have a good knowledge of its microhabitat requirements. We investigated determinants and patterns of C. cerdo distribution within individual old, open-grown oaks. Trees inhabited by this species were climbed, and the number of exit holes and environmental variables recorded at two sites in the Czech Republic. Distribution of exit holes in relation to height above the ground, trunk shading by branches, orientation in terms of the four cardinal directions, diameter, surface and volume of inhabited tree parts were investigated. This study revealed that the number of exit holes in the trunks of large open-grown oaks was positively associated with the diameter of the trunk and openness and negatively with height above the ground, and the effects of diameter and openness changed with height. The number of exit holes in the surface of a trunk was also associated with the cardinal orientation of the surface. Approximately half of both C. cerdo populations studied developed less than 4 m and approximately a third less than 2 m above the ground. This indicates that most C. cerdo develop near the ground. Active management that prevents canopy closure is thus crucial for the survival of C. cerdo and searching for exit holes is an effective method of detecting sites inhabited by this species., Jan Albert, Michal Platek, Lukas Cizek., and Obsahuje seznam literatury
Rights:
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