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2. Factors determining local and seasonal variation in abundance of Harmonia axyridis (Coleoptera: Coccinellidae) in Central Europe
- Creator:
- Honěk, Alois , Brabec, Marek , Martinková, Zdenka , Dixon, Anthony F.G., Pekár, Stano , and Skuhrovec, Jiří
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Coleoptera, Coccinellidae, Sternorrhyncha, Aphididae, Harmonia axyridis, Eucallipterus tiliae, adult, larva, seasonal dynamics, abundance, annual variation, and Central Europe
- Language:
- English
- Description:
- To determine the causes of the variation in the seasonal dynamics of Harmonia axyridis (Pallas) in Central Europe, numbers of adults and larvae of this invasive species were recorded on trees (Acer, Betula, Tilia) throughout the growing seasons from 2011 to 2016. Each year beetles were collected every two weeks, using a standardized sweeping method. The seasonal dynamics was expressed as plots of abundance (number of individuals per 100 sweeps) against time (Julian day) and these plots (seasonal profi les) were compared in terms of their size (area under the seasonal profi le curve), range, timing and height of the mode (maximum abundance). Timing and size of seasonal profi les varied among hostplants, years and sites. Abundance of larvae paralleled aphid occurrence and peak abundance of adults followed that of larvae 10 to 20 days later. Population dynamics before and after the peak were determined by dispersal. Adults arrived at sites before the start of aphid population growth and persisted there long after aphid populations collapsed. The abundance of H. axyridis decreased from 2011 to 2013 and then increased, achieving the previous levels recorded in 2015 and 2016. The variation in seasonal profi les revealed that H. axyridis, in terms of its response to environmental conditions, is a plastic species and this fl exibility is an important factor in its invasive success.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3. Merlax bohemicus gen. n., sp. n. , a new fossil dragonfly from the Lower Miocene of northern Bohemia (Odoanta: Aeshnidae)
- Creator:
- Prokop, Jakub and Nel, André
- Type:
- article, model:article, and TEXT
- Subject:
- Odonata, Aeshnidae, Anactini, adult, new genus, fossil, Lower Miocene, Czech Republic, and Europe
- Language:
- English
- Description:
- Two aeshnid dragonflies are described from the Lower Miocene deposits in the Bílina mine in the north of the Czech Republic, including a new genus and species of Anactini, Merlax bohemicus gen. n., sp. n., and a further specimen assigned to the genus Aeshna.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
4. Rediscovery, redescription and reclassification of Beludzhia phylloteliptera (Diptera: Sarcophagidae: Miltogramminae)
- Creator:
- Szpila, Krzysztof and Pape, Thomas
- Type:
- article, model:article, and TEXT
- Subject:
- Sarcophagidae, Miltogramminae, redescription, systematics, larva, adult, morphology, SEM, Beludzhia, Dolichotachina, and Phylloteles
- Language:
- English
- Description:
- The species Beludzhia phylloteliptera Rohdendorf is redescribed from adult males and females as well as all larval instars collected in the United Arab Emirates. The morphology of the first instar larva is strikingly similar to that of Dolichotachina marginella (Wiedemann) and Phylloteles pictipennis Loew, all of which are here documented for the first time. These three generic representatives share several character states, which are probably plesiomorphic relative to the condition observed in other miltogrammine larvae, but the uniquely shaped, slender mouthhook, a cushion- or pad-like lobe behind the maxillary palpus (cheek organ), the antero-ventral segmental prolegs of the first instar larva, and the integumental warts of the third instar larvae, are shared character states not known from any other species of Sarcophagidae. Beludzhia Rohdendorf is therefore placed with Dolichotachina Villeneuve and Phylloteles Loew in the tribe Phyllotelini.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
5. The development of the tegument in ontogenesis of Triaenophorus nodulosus (Cestoda: Pseudophyllidea)
- Creator:
- Davydov, V. G., Korneva, J. V., and Kuperman, B. I.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Pseudophyllidea, Triaenophorus, oncosphere, procercoid, plerocercoid, adult, fine structure, and tegument
- Language:
- English
- Description:
- The tegument ultrastructure of the cestode Triaenophorus nodulosus has been studied in the stages of oncosphere, procercoid, plerocercoid and adult. The syncytium of primary tegument has glandular origin and is located in the peripheral areas of the oncosphere. The primary tegument degenerates at the initial stages of the procercoid development and is replaced with secondary tegument persisting throughout all following stages of the worm’s development. Two ways of microthrix formation on the body surface of procercoid were discovered. The formation of the cyst consisting of fibrillar material around the plerocercoid was observed. It fills spaces between numerous finger-like évaginations of plerocercoid’s tegument. The structural differentiation of tegument and microtriches was demonstrated on the scolex and all parts of strabila of T. nodulosus.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public