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362. Laboratoř genetiky ryb Ústavu živočišné fyziologie a genetiky Akademie věd ČR, v. v. i
- Creator:
- Petr Ráb
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, zoologie, 2, and 59
- Language:
- Czech
- Description:
- Petr Ráb.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
363. Laboratory studies on intraguild predation and cannibalism among coccinellid larvae (Coleoptera: Coccinellidae)
- Creator:
- Rondoni, Gabriele, Onofri, Andrea, and Ricci, Carlo
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Coccinellidae, Harmonia axyridis, intraguild predation, biological control, invasive species, Italy, interval-censored survival analysis, 2, and 59
- Language:
- English
- Description:
- 1_Intraguild predation (IGP) and cannibalism occur in the field and could affect the dominance structure of guilds of coccinellid species. The exotic biological control agent Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) is now well established in most areas of Northern and Central Italy, but it is unclear what effect this species could have on native dominant and non-dominant coccinellids with which it co-occurs. In order to predict the trophic interactions in coccinellid guilds and the likely effect of H. axyridis, the incidence of IGP and cannibalism among the following six species were evaluated under laboratory conditions: H. axyridis, three native dominant species, Adalia bipunctata (L.), Oenopia conglobata (L.) and Coccinella septempunctata L. and two native non-dominant species, Platynaspis luteorubra (Goeze) and Scymnus apetzi (Mulsant). Unfed and fed fourth instar larvae of the above species were paired in an experimental arena and the incidence of predation recorded over a period of 24 h. In absence of aphids, the survival probabilities (SP) of A. bipunctata and O. conglobata were lowest when paired with either C. septempunctata or H. axyridis (< 0.20 SP after 24 h). The SP of C. septempunctata was similar if paired with either a conspecific larva or H. axyridis (< 0.34 SP after 24 h) and that of H. axyridis was reduced similarly if paired with either a conspecific larva or C. septempunctata (> 0.71 SP after 24 h). The SP of P. luteorubra was lower when paired with A. bipunctata and C. septempunctata (< 0.07 SP after 24 h) than with other species and that of S. apetzi was greatly reduced when paired with all the dominant and exotic species (< 0.27 SP after 24h)., 2_In presence of aphids no predatory events occurred in most combinations. H. axyridis acted as a strong predator of native dominant and non-dominant coccinellids when the aphids are scarce. We did not find any evidence, however, that the incidence of IGP among exotic and native species is higher than either IGP or cannibalism in native species. The likelihood of IGP occurring in the field is discussed., Gabriele Rondoni, Andrea Onofri, Carlo Ricci., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
364. Lalokoploutvé ryby
- Creator:
- Přikryl, Tomáš
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, zoologie, ryby, obojživelníci, plazi, paleontologie, fishes, amphibians, reptiles, paleontology, 2, and 59
- Language:
- Czech
- Description:
- K lalokoploutvým rybám lze vysledovat původ nejstarších čtvernožců (tetrapodů). Přestože dnes přežívají jen dva druhy rodu latimerie (Latimeria), v minulosti tyto ryby představovaly poměrně úspěšnou skupinu vodních obratlovců. Článek popisuje hlavní znaky jednotlivých skupin a jejich minulost., Fossil lobe-finned fishes can be traced as direct ancestors of the first terrestrial tetrapods. Although two species of one genus (coelacanths Latimeria chalumnae and L. menadoensis) have survived to these days, the lobe-finned fishes formed a successful group of aquatic vertebrates in the past. The main features and history of their subgroups are described., and Tomáš Přikryl.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
365. Lancaster J. & Briers R.A (eds.).: Aquatic Insects: Challenges to Populations. Proceedings of the Royal Entomological Society’s 24th Symposium
- Creator:
- Boukal, D.
- Type:
- article, recenze, model:article, and TEXT
- Subject:
- Zoologie, zoologie, 2, and 59
- Language:
- English
- Description:
- [autor recenze] D. Boukal.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
366. Landscape structure affects activity density, body size and fecundity of Pardosa wolf spiders (Araneae: Lycosidae) in winter oilseed rape
- Creator:
- Drapela, Thomas, Frank, Thomas, Heer, Xaver, Moser, Dietmar, and Zaller, Johann G.
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, agroecology, Araneae, Lycosidae, Pardosa agrestis, generalist predator, Brassica napus, oilseed rape, landscape, multiple spatial scales, 2, and 59
- Language:
- English
- Description:
- In large parts of Europe Pardosa spp. (Lycosidae) are among the most abundant wolf spiders in arable fields and potentially important natural control agents of pests. We studied the influence of landscape factors on activity density, adult body size and fecundity of P. agrestis in 29 winter oilseed rape fields (Brassica napus L.) in Eastern Austria using pitfall traps. Landscape data were obtained for eight circular landscape sections around each field (radii 250-2000 m). Multivariate regression models were used to analyze the data. Activity density was highest when the length of strips of grassy road-sides in the surroundings was highest and distance to the next grassy fallow lowest. Body size was negatively related to activity density and to the length of road-side strips and positively to woody areas in the vicinity of the fields. Clutch size was unrelated to any of the landscape factors tested but was positively correlated with female body size. Woody areas and grassy fallow in the close vicinity of the fields had a positive influence on number of offspring per female and total number of offspring. These results indicate that various non-crop components in the landscape surrounding oilseed rape fields can specifically influence the activity density and fitness-related traits of P. agrestis in crops. The possible role of Pardosa spp. in natural pest control is discussed. and Thomas Drapela, Thomas Frank, Xaver Heer, Dietmar Moser, Johann G. Zaller.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
367. Larval crowding leads to unusual reaction norms for size and time at maturity in a geometrid moth (Lepidoptera: Geometridae)
- Creator:
- Vellau, Helen and Tammaru, Toomas
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Lepidoptera, Geometridae, reaction norm, larval crowding, size and time at maturity, Ematurga atomaria, 2, and 59
- Language:
- English
- Description:
- The theory of life history evolution generally predicts a negative across-environment correlation between development time and size at maturity in response to variations in environmental quality. Deviations from this pattern occur under specific circumstances. In particular, organisms may mature both early and at a small size when (1) some ultimate change (e.g. time constraint, resource exhaustion) in the environment precludes further growth, or (2) when there are predictable among-environment differences in mortality rates. The first scenario is frequently documented in insects but evidence for the second possibility is scarce. Here we report a crowding-induced plastic response resulting in a clear positive across-environment correlation between final weight and development time in a geometrid moth. The response was apparent during the entire larval period and in the last larval instar. Crowding also led to increased growth rates. As outbreaks have not been reported for this species it is unlikely that early pupation is a response to anticipated food shortage. Instead, we suggest that crowded larvae may perceive a higher risk of predation, perhaps because they are unable to distinguish conspecifics from potential predators. A possibility for a plastic increase in growth rate implies that the uncrowded larvae grow at submaximal rates, which indicates a cost of high growth rate., Helen Vellau, Toomas Tammaru., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
368. Larval descriptions of five Oriental bamboo-inhabiting Acroceratitis species (Diptera: Tephritidae: Dacinae) with notes on their biology
- Creator:
- Schneider, Alexander, Kovac, Damir, Steck, Gary J, and Freidberg, Amnon
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Zoologie, vrtulovití, housenice, morfologie (biologie), biologie, lipnicovité, bambus, Tephritidae, larvae, morphology (biology), biology, Poaceae, Bamboo, Thajsko, Thailand, Gastrozonini, Acroceratitis, first description, 2, and 59
- Language:
- English
- Description:
- Third instar larvae of the genus Acroceratitis Hendel from North Thailand are described for the first time. They belong to A. ceratitina (Bezzi), A. distincta (Zia), A. histrionica (de Meijere), A. incompleta Hardy, and A. septemmaculata Hardy. Short descriptions of eggs, empty egg shells, and puparia are also presented. Acroceratitis larvae infest shoots of bamboo (Poaceae). Larval host plants of the studied species are Bambusa polymorpha Munro, Cephalostachyum pergracile Munro, Dendrocalamus hamiltoni Nees and Arnott ex Munro, D. strictus (Roxbourgh), Dendrocalamus sp. (unidentified) and Pseudoxytenanthera albociliata (Munro). The morphological characters of Acroceratitis larvae are compared with those of other Gastrozonini described so far. A key to Acroceratitis larvae is provided. Acroceratitis ceratitina, A. incompleta and A. septemmaculata are morphologically similar and clearly differentiated from A. distincta and A. histrionica by the lack of additional papillar sensilla on the labial lobe, the arrangement of the spinules on the creeping welts and other characters. The morphological differences between the two groups coincide with the type of substrate utilized by their larvae: A. ceratitina, A. incompleta and A. septemmaculata larvae feed in young and soft internode walls, while A. distincta and A. histrionica utilize harder bamboo tissue of already elongated bamboo shoot internodes. Acroceratitis histrionica larvae are special within the Gastrozonini, because they develop exclusively in cavities formed by the internode surface and the protecting culm sheath. Factors influencing spatial utilization of larval resources, preference for upright shoots as breeding substrate, larval behavior, types of bamboo damage caused by different species and attraction to sweat and urine in the adults are discussed., Alexander Schneider, Damir Kovac, Gary J. Steck, Amnon Freidberg., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
369. Larval morphology of Scydmaenus tarsatus and S. hellwigii, with notes on feeding behaviour and a review of the bibliography on the preimaginal stages of ant-like stone beetles (Coleoptera: Staphylinidae: Scydmaeninae)
- Creator:
- Jaloszynsky, Pawel and Kilian, Aleksandra
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Coleoptera, Staphylinidae, Scydmaeninae, Scydmaenini, Scydmaenus, Palaearctic, larval morphology, behaviour, feeding, 2, and 59
- Language:
- English
- Description:
- Morphology of mature larvae of two Central European species of Scydmaenus Latreille is described and illustrated: S. (s. str.) tarsatus Müller & Kunze and S. (Cholerus) hellwigii (Herbst). Inaccuracies in previous descriptions of S. tarsatus are discussed and the following combination of characters is defined as diagnostic for Scydmaenus: epicranial sutures reaching posteromedian margins of antennal insertions; presence of a single pair of stemmata and epicranial supraantennal pits; anterior row of subtriangular teeth on epipharynx; mandibles falciform and without mesal teeth; antennomere 3 rudimentary; antennal sensory appendage subconical and asymmetrical; maxilla with galea and lacinia; labium strongly constricted between mentum and prementum; thoracic tergites undivided along midline; head capsule, thoracic tergites, laterotergites and abdominal segments except sternite 1 densely setose; thoracic sternites and abdominal sternite1 largely asetose; and lack of urogomphi. We also describe the feeding behaviour of immature S. tarsatus and demonstrate for the first time that Scydmaeninae larvae can feed on live springtails and not armoured mites. In the introduction we provide a summary of the literature on all hitherto known preimaginal stages of Scydmaeninae., Pawel Jaloszynski, Aleksandra Kilian., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
370. Life cycle and growth pattern of the endangered myrmecophilous Microdon myrmicae (Diptera: Syrphidae)
- Creator:
- Witek, Magdalena, Canterino, Sara, Balletto, Emilio, and Bonelli, Simona
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Syrphidae, hoverflies, Microdon myrmicae, ants, Myrmica, Maculinea, social parasites, larval ecology, polymorphic growth, 2, and 59
- Language:
- English
- Description:
- In Europe there are only a few species of the syrphid fly Microdon, which live in the nests of various genera of ants. For most of these rare flies, details of their biology, larval behaviour and relationships with their hosts are still not yet well known. In this paper we present data on the life cycle, feeding behaviour and growth pattern of Microdon myrmicae, a social parasite of Myrmica ants and compare it with two species of Maculinea butterflies similarly parasitizing Myrmica ant colonies. M. myrmicae has three larval instars and overwinters as a third instar. Eggs and 1st instar larvae are ignored by ants, which indicate that they are “chemically insignificant”. 2nd and 3rd instar larvae feed on small ant brood. M.myrmicae larvae grow rapidly from May to July and later in the year the host colony only serves as shelter for overwintering. Like Maculinea alcon, larvae of M. myrmicae are numerous in Myrmica nests and more numerous than those of Maculinea teleius. Since the larvae of Microdon feed on an abundance of young ant brood, they experience low level of scramble competition and although many may develop in an ant’s nest they have probably little effect on host colony fitness., Magdalena Witek ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public