Flowers of dicotyledonous plants host communities of arthropod species. We studied the community associated with dandelion (Taraxacum section Ruderalia), a complex of apomictic micro-species abundant in central Europe. Identification of microspecies in the field was impracticable. These plants produce an abundance of flowers that host arthropod communities that are not yet fully documented. We investigated species occurrence, its diurnal and seasonal variation and some of the factors that determine the abundance of the dominant species. Insect and spiders were collected from 2010 to 2012 at a locality in Prague. Whole capitula were harvested at weekly intervals and resident arthropods were identified. Diurnal variation in insect presence and the effect of pollen and microclimate on some of the species were also examined. The insect community (> 200 species) consisted mainly of species of Hymenoptera (86 spp.), Coleoptera (56 spp.), Diptera (46 spp.) and Heteroptera (23 spp.). The most abundant were Thysanoptera (2 spp.). Pollen eaters/collectors and nectar feeders dominated over predators and occasional visitors. From April to mid-August, the insect community was dominated by Coleoptera, and later by Diptera and Hymenoptera. Except for Meligethes spp. and species breeding in the capitula, the insects occupied flowers during the daytime when the flowers were open (10-12 h in spring and only 2-4 h in late summer). The presence of Meligethes spp. in particular flowers was associated with the presence of pollen; the occurrence of Byturus ochraceus with pollen and flower temperature. Although pollination is not necessary, dandelion plants produce both nectar and pollen. The community of arthropods that visit dandelion flowers is rich despite their being ephemeral.The composition of local faunas of flower visitors, presence of floral rewards and flower microclimate are important factors determining the composition of the flower community., Alois Honěk, Zdenka Martinková, Jiří Skuhrovec, Miroslav Barták, Jan Bezděk, Petr Bogusch, Jiří Hadrava, Jiří Hájek, Petr Janšta, Josef Jelínek, Jan Kirschner, Vítězslav Kubáň, Stano Pekár, Pavel Průdek, Pavel Štys, Jan Šumpich., and Obsahuje bibliografii
The mouthparts of the spoon-winged lacewing Nemoptera sinuata are adapted for the uptake of pollen and nectar. Form and function of the mouthparts are described, and the technique of food uptake is discussed in context with flower-visiting behaviour and floral architecture of the preferred flowers. The maxillae are the main organs for food uptake. The brush-shaped laciniae, galeae and maxillary palpi form a functional unit which can be extended by the action of the cardo-stipes joint. Video analyses of the mouthpart movements distinguished different patterns of maxillary motions which occur in nectar feeding or pollen collecting. The flower-visiting behaviour and the specialised mouthparts of the Nemopteridae are derived traits which probably evolved from predatory and biting/chewing mouthparts within the Neuroptera.
The Rejvíz bog is an extensive mire complex in Central Europe, with up to 7 m deep sediments and two natural lakes. Recent vegetation is one of the best preserved examples of Pinus uncinata subsp. uliginosa (syn. P. rotundata) bog woodland in Central Europe. The origin and development of the mire and changes in the surrounding landscape vegetation are reconstructed using sediment stratigraphy, radiocarbon dating, pollen analysis and plant-macrofossils analysis, with particular emphasis on the processes that resulted in the origin of Rejvíz bog and on pine woodland dynamics. Based on identified species the water level changes were reconstructed. The sediment started to accumulate more than 9000 years ago at an open mixed-woodland spring with Dichodontium palustre. Later, poor fen vegetation with sedges and horsetails developed. Around 6170 cal. yr BC the fen became inundated for 2000 years and (semi)aquatic vegetation thrived. Next step in the succession followed a decline in water level which resulted in the development of drier oligothrophic vegetationwith a high representation of pine and dwarf shrubs. After ca 1020 cal. yr BC the mire became the bog it is now. Three wooded stages appeared in both the minerotrophic and ombrotrophic developmental phases: before 6720 cal. yr BC, during ca 1960–1020 cal. yr BC and recently. The vegetation in the surrounding landscape developed without marked human interventions up till ca the last six or five centuries, when deforestation and later settlement took place. Comparison with published data from the Góry Bystrzyckie/Orlické hory Mts suggests that not only regional, but also local vegetation changed in a similar way across the middle-altitude eastern Sudetes, following oscillations in climate rather than local changes in mire water regime.
Two species of the Chrysoperla carnea complex: Ch. carnea sensu Henry and Ch. lucasina, occur in the crop environment in western France. Within the framework of a conservation biological control program for protected seed crops, the pollen consumption of these common green lacewings was investigated. The diverticulum contents of collected specimens were analysed to determine their food preference. Ch. carnea sensu Henry and Ch. lucasina are opportunistic feeders, which are attracted to large patches of flowering plants. The establishment of monitoring an attractive environment for these predators is discussed.
Bílé Karpaty Mts harbour some of the most species-rich managed grasslands in Europe, which contain a number of rare and disjunctly distributed species. Besides specific local environmental factors, the long Holocene history may explain the uniqueness of these grasslands. However, historical interpretations of the palaeoecological evidence from the region are far from unequivocal. While palaeomalacological data indicate persistence of open habitats throughout the entire Holocene, fragmentary pollen data support the hypothesis of a medieval origin of the grasslands. This paper reviews the available phytogeographical, archaeological and palaeoecological knowledge that provides indirect evidence for a prehistoric origin of the grasslands in the Bílé Karpaty Mts. High concentration of rare heliophilous species with a disjunct distribution in the south-western part of the Bílé Karpaty Mts suggest their long-term persistence. The archaeological findings provide evidence for the existence of prehistoric human settlement in this region since the Neolithic (Middle Holocene). Direct evidence for the existence of open human-influenced habitats before medieval times, based on the results of a multi-proxy analysis (macrofossils, molluscs and pollen) of an organic sediment dated back to Roman Age, is also provided. The results indicate the existence of an ancient cultural landscape with a mosaic of open grasslands, natural forests and fields. It is concluded that the evidence presented in this paper supports the hypothesis of prehistoric, rather than a medieval origin of the species-rich grasslands in the Bílé Karpaty Mts.
The pollens consumed by common green lacewings Chrysoperla spp. in crop environment in western France, were analysed. The diverticulum contents including quantity of pollen of Chrysoperla adults were analysed to compare a feeding behaviour between the sexes. Females consume more pollen than males. The feeding behaviour of the two main species present was compared, yielding new insights into differences between species within the complex Chrysoperla carnea (Stephens).