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71.
Abstract: The lower Cambrian Emu Bay Shale on Kangaroo Island, South Australia, contains the only known Cambrian Burgess Shale‐type biota in Australia. Two new lamellipedian arthropods, Emucaris fava gen. et sp. nov. and Kangacaris zhangi gen. et sp. nov., from the Emu Bay Shale Lagerstätte are described as monotypic genera that are resolved cladistically as a monophyletic group that is sister to Naraoiidae + Liwiidae and classified within the Nektaspida as a new family Emucarididae. Shared derived characters of Emucarididae involve a bipartite, elongate hypostome and elongation of the pygidium relative to the cephalic shield and very short thorax. A monophyletic Liwiidae is composed of Liwia and the Ordovician Tariccoia + Soomaspis but excludes Buenaspis, and even the membership of Buenaspis in Nektaspida is contradicted amongst the shortest cladograms. New morphological interpretations favour affinities of Kwanyinaspis with Conciliterga rather than with Aglaspidida, and Phytophilaspis with Petalopleura.  相似文献   
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The genus Anaplasma (Rickettsiales: Anaplasmataceae) includes species of medical and veterinary importance. The presence of Anaplasma spp. in ticks from birds, as well as in Haemaphysalis punctata (Ixodida: Ixodidae) specimens collected from cattle and vegetation in northern Spain was investigated. A total of 336 ticks from birds [174 Ixodes frontalis (Ixodida: Ixodidae), 108 H. punctata, 34 Hyalomma marginatum (Ixodida: Ixodidae), 17 Ixodes ricinus (Ixodida: Ixodidae) and three Ixodes spp.], and 181 H. punctata specimens collected from cattle (n = 71) and vegetation (n = 110) were analysed. Anaplasma bovis was detected in five H. punctata, including two from birds (1.9%) and three from vegetation (2.7%). Four I. frontalis (2.3%) (one co‐infected with ‘Candidatus Midichloria mitochondrii’) and one I. ricinus (5.9%) removed from birds, as well as four H. punctata (5.6%) collected from cattle showed Anaplasma phagocytophilum infection. In addition, Anaplasma centrale was found in two H. punctata, one from a cow (1.4%) and the other from vegetation (0.9%). This study represents the first evidence of the presence of A. bovis in European ticks, and reports the first detection of A. bovis and A. centrale in H. punctata, and the first finding of A. phagocytophilum and ‘Ca. Midichloria mitochondrii’ in I. frontalis.  相似文献   
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Abstract: We compared methods of assessing the diet of the bearded vulture (Gypaetus barbatus) during the nestling period in the Pyrenees, northeast Spain. We determined diet from direct observations of food items delivered to the nest, recent prey remains present in the nest, remains collected in the nests after fledging, and remains collected in the ossuaries (bone-breaking sites). Data suggest that direct observation (food items delivered and recent prey remains present in the nest) is the only valid method of assessing the bearded vulture's diet accurately. Remains overestimated the presence of large mammals, such as cows (Bos taurus) and horses (Equus caballus), Suidae, and birds; delivered samples contained a higher proportion of small mammals, medium-sized mammals, micromammals, and reptiles. Ossuaries also differed from delivered samples because remains collected there overestimated large and medium-sized mammals. Concerning the skeletal parts, ossuaries, compared to all other methods, underestimated extremities and overestimated long bones, such as femur, humeri and tibiae, scapulae, vertebrae, and skulls. Remains samples, which overestimated scapulae, also differed from delivered and present samples. Our results suggest that bearded vultures favor extremities of prey (78% of the mammal remains, which make up 95% of the diet). The prevalence of small carcasses (almost 17%) suggests that vultures select small animals for food for the young. Because food quality may influence breeding success, future conservation projects based on the selective provision of food to breeding pairs should add to food stations meat remains and small carcasses consistent with our assessment of the birds’ dietary needs.  相似文献   
76.
Using Drosophila melanogaster, we explore the consequences of restricted panmixia (RP) on the genetic load caused by segregating deleterious recessive alleles in a population where females mate a full sib with probability about ½ and mate randomly otherwise. We find that this breeding structure purges roughly half the load concealed in heterozygous condition. Furthermore, fitness did not increase after panmixia was restored, implying that, during RP, the excess of expressed load induced by inbreeding had also been efficiently purged. We find evidences for adaptation to laboratory conditions and to specific selective pressures imposed by the RP protocol. We discuss some of the consequences of these results, both for the evolution of population breeding structures and for the design of conservation programmes.  相似文献   
77.
ABSTRACT Capturing animals is an essential tool of wildlife management, but the use of capture devices is being affected by public pressures on an international scale. In Europe, and particularly Spain, foxes (Vulpes vulpes) are often captured using traditional methods such as nonlocking Spanish Snares (SS) set in an ad hoc fence line known as an alar, but these traditional European methods are rarely compared to modernly described restraints such as the Wisconsin Cable Restraint (WR). We evaluated rates of efficiency, selectivity, injury, and impacts to foxes and nontarget species when using SS (as traditionally set in an alar) or WR within alars or on trails in Castilla-La Mancha, Spain. During 40,372 trap-nights from summer to winter of 2007, we captured 64 foxes, and 8 of 23 potential nontarget species. Our results indicated that WR set in trails were more efficient (0.28 capture rate) for capturing red foxes than SS set in an alar (0.11 capture rate). Relative to injury, foxes captured with the WR in the alar (95.4%), and WR in trails (90.5%), and the SS (90.9%) showed no indicators of poor welfare, and injury score analysis indicated that injuries were of similar magnitude for all capture devices. Overall, the WR set in trails may have performed the best, but all 3 methods are likely sufficient for capturing foxes with minimal injury, acceptable efficiency, and acceptable impact to foxes and sympatric nontarget species. Thus, wildlife managers in Spain and elsewhere can apply our findings to optimize capture and management of foxes.  相似文献   
78.
Stegomyia aegypti (= Aedes aegypti) (Diptera: Culicidae) is a species of mosquito that is currently widespread in Mexico. Historically, the mosquito has been distributed across most tropical and subtropical areas lower than 1700 m a.s.l. Currently, populations that are found at higher altitudes in regions with cold and dry climates suggest that these conditions do not limit the colonization and population growth of S. aegypti. During a survey of mosquitoes in September 2015, larvae of S. aegypti mosquitoes were found in two different localities in Mexico City, which is located at about 2250 m a.s.l. Mexico City is the most populous city in Mexico and has inefficient drainage and water supply systems. These factors may result in the provision of numerous larval breeding sites. Mosquito monitoring and surveillance are now priorities for the city.  相似文献   
79.
The activity of the photosynthetic carbon‐fixing enzyme, ribulose 1,5‐bisphosphate carboxylase/oxygenase (Rubisco), is partially inhibited by arsenite in the millimolar concentration range. However, micromolar arsenite can fully inhibit Rubisco in the presence of a potentiating monothiol such as cysteine, cysteamine, 2‐mercaptoethanol or N‐acetylcysteine, but not glutathione. Arsenite reacts specifically with the vicinal Cys172‐Cys192 from the large subunit of Rubisco and with the monothiol to establish a ternary complex, which is suggested to be a trithioarsenical. The stability of the complex is strongly dependent on the nature of the monothiol. Enzyme activity is fully recovered through the disassembly of the complex after eliminating arsenite and/or the thiol from the medium. The synergic combination of arsenite and a monothiol acts also in vivo stopping carbon dioxide fixation in illuminated cultures of Chlamydomonas reinhardtii. Again, this effect may be reverted by washing the cells. However, in vivo inhibition does not result from the blocking of Rubisco since mutant strains carrying Rubiscos with Cys172 and/or Cys192 substitutions (which are insensitive to arsenite in vitro) are also arrested. This suggests the existence of a specific sensor controlling carbon fixation that is even more sensitive than Rubisco to the arsenite–thiol synergism.  相似文献   
80.
Abstract: Abundant material from a new quarry excavated in the lower Cambrian Emu Bay Shale (Kangaroo Island, South Australia) and, particularly, the preservation of soft‐bodied features previously unknown from this Burgess Shale‐type locality, permit the revision of two bivalved arthropod taxa described in the late 1970s, Isoxys communis and Tuzoia australis. The collections have also produced fossils belonging to two new species: Isoxys glaessneri and Tuzoia sp. Among the soft parts preserved in these taxa are stalked eyes, digestive structures and cephalic and trunk appendages, rivalling in quality and quantity those described from better‐known Lagerstätten, notably the lower Cambrian Chengjiang fauna of China and the middle Cambrian Burgess Shale of Canada.  相似文献   
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