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Azovsky A.,Moscow State University | Mazei Y.,Penza State Pedagogical University
Global Ecology and Biogeography | Year: 2013

Aim The biogeography and global distribution of protists has long been disputed, with two primary, opposing views. To test these two sets of views in greater detail, we have compiled the available data for marine benthic ciliates and assessed the general patterns of their diversity and distribution compared with Metazoa. Location World-wide. Methods A comprehensive database (1342 species, over 350 sources) was used to analyse the diversity, distribution, species occurrences and range size distribution of free-living ciliates that inhabit marine sediments in 17 geographical regions. Results Twenty-five per cent of the species have been found in a single region only, whereas 18% are widespread (they occur in more than half the regions covering both hemispheres). Only 5-7% of regional faunas are endemic, which is much lower than for macroorganisms. Regional diversity depends neither on total area nor on coastline length and does not show any obvious latitudinal trends, but correlates highly with the investigation effort expended in a region and (negatively) with the average salinity. A comparison of species composition reveals distinctions between the Arctic Area (the White, Barents and Kara seas), Laurasian Area (north Atlantic, north Pacific and European seas), Gondwanian Area (Southern Ocean) and the Antarctic. No clear geographical correlations are found for faunistic composition at the genus or family levels. There is the tendency to narrow the latitudinal ranges for species found at high latitudes (reversal of Rapoport's rule). Main conclusions Undersampling and data insufficiency are the key factors affecting the observed diversity and distribution of microorganisms. Nevertheless, marine benthic ciliates demonstrate certain patterns that generally agree with the 'moderate endemicity' model (Foissner, 2004, 2008), but consistently contradict the regularities commonly observed for multicellular taxa. Thus, ciliates do have a biogeography, but their macroecological patterns may be different in some respects from that of macroorganisms. © 2012 Blackwell Publishing Ltd. Source


Payne R.J.,Manchester Metropolitan University | Payne R.J.,University of Manchester | Lamentowicz M.,Adam Mickiewicz University | Der Knaap W.O.V.,University of Bern | And 3 more authors.
Review of Palaeobotany and Palynology | Year: 2012

Among the non-pollen micro-fossils commonly encountered in Quaternary sediment samples prepared for pollen analysis are many shells of testate amoebae. Testate amoebae are eukaryotic micro-organisms which are increasingly used in ecological and palaeoecological studies, particularly as indicators of hydrological change in . Sphagnum-dominated peatlands. In this study we address the extent to which testate amoebae are used in palynological research, the key challenges to more widespread use, and the extent to which ecological information is retained in the testate amoeba assemblages of standard palynological slides. To achieve this we review the literature on the use of testate amoebae in palynology, compare testate amoeba records produced by palynological and water-based preparation methods and carry out simulations using previously-derived datasets. Our results show that testate amoebae are widely encountered in Quaternary palynological studies, primarily in peatlands, but the information which they can provide is undermined by limited taxonomic knowledge. Many taxa are destroyed in pollen preparations, but for taxa that are retained patterns of abundance parallel those determined using water-based preparation methods. Although the loss of sensitive taxa limits the ecological information contained in testate amoeba assemblages the information preserved is likely to be useful in a multiproxy approach to palaeoenvironmental reconstruction. To help improve taxonomic awareness and encourage the use of testate amoebae in palynology we present a basic introduction to testate amoeba taxonomy and a guide to the taxonomic literature. © 2011 Elsevier B.V.. Source


Smirnov D.G.,Penza State Pedagogical University | Vekhnik V.P.,Zhiguli Reserve
Zoologicheskii Zhurnal | Year: 2014

For eight settled species ofbats inhabiting the Middle Volga River basin, a sex ratio in different periods of their activity was determined. Myotis daubentonii and Plecotus auritus females were shown to prevail in places of mass hibernation of animals, whereas in the other species, males predominated. In summertime, in the areas nearby the hibernation places, the number of M. brandtii, M. daubentonii, M. dasycneme and P. auritus males was much higher; the equal sex ratio was noted for M. nattererii, M. mystacinus and Eptesicus serotinus; the number of E. nilssonii females predominated over that of its males. Beyond the hibernation area, the share of males was lower. A scheme of variants reflecting the degree of overlap and differentiation of the areas of hibernation and reproduction and the spatial ratio between the sex groups is proposed. It is shown that for many settled bat species, a wide overlap and some differentiation of these areas are characteristic features. The most spatial segregation between adult males and reproductive females was determined in M. daubentonii and M. dasycneme. In M. nattereri and probably in PI. auritus, it is expressed to a lesser extent. The wide overlap of the hibernation and reproductive areas was noted for M. mystacinus, E. nilssonii, and E. serotinus. The cases of overlap and separation of the same areas were fixed in M. brandtii. Source


Smirnov D.G.,Penza State Pedagogical University | Vekhnik V.P.,Zhigulevsk State Reserve
Biology Bulletin | Year: 2013

The trophic ecology of Nyctalus lasiopterus in the Samara Bend during July 2008-2010 has been studied. It has been revealed that the main feeding stations for this species are old ecotonal black poplar stands and willow groves. N. lasiopterus keeps to opportunistic foraging by using easily accessible and properly sized food objects. Having analyzed 129 fecal samples, we singled out 10 categories of food objects belonging to six orders of insects. The representatives of Lepidoptera constitute the major part of the ration. Their abundance rates undergo asynchronous changes relative to each other. Homoptera and Neuroptera are found more rarely in the feces. Orthoptera and Diptera are extremely rare. Besides insects, bird feathers were found in 14 faecal samples of N. lasiopterus. They made up from 60 to 90% of the total fecal mass. © 2013 Pleiades Publishing, Ltd. Source


Bobrov A.,Moscow State University | Shimano S.,Miyagi University of Education | Mazei Y.,Penza State Pedagogical University
Acta Protozoologica | Year: 2012

Two new species of Deharvengia and Assulina are described from samples in the mountain forests of Honshu Is. (Japan). Morphometric analysis showed low variability of their morphological characteristics with coefficients of variation ranging between 1.4 and 9.1% for the two new species. An amended description of the genus Deharvengia is provided. Source

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