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ANDREW J. GOODAY OLGA E. KAMENSKAYA TOMAS CEDHAGEN 《Zoological Journal of the Linnean Society》2007,151(2):219-251
Based on samples from the south-east Atlantic and Southern Ocean collected during the ANDEEP III campaign we describe three new species, Ipoa pennata sp. nov., Septuma stellata sp. nov. and Skeletonia variabilis gen. et sp. nov. , of the enigmatic deep-sea foraminiferan superfamily Komokiacea. A further six species, Ipoa fragila Tendal & Hessler, 1977, Komokia multiramosa Tendal & Hessler, 1977, Normanina conferta (Norman, 1878), Septuma ocotillo Tendal & Hessler, 1977, S. brachyramosa Kamenskaya, 1993, and S. komokiformis Kamenskaya 1993, are redescribed. Together, these nine species occurred at 14 stations across the depth range 1549–4935 m. Normanina conferta was found at 11 stations (1579–4935 m); S. ocotillo (4526–4935 m), S. brachyramosa (1819–4730 m) and S. stellata (2603–4934 m) at six stations each; I. fragila (4649–4934 m) at five stations; K. multiramosa (4700–4935) and S. variabilis (4696–4932 m) at four stations each; I. pennata (4803–4934 m) at three stations and S. komokiformis (3103–4526 m) at two stations. Five species occur in both the North Atlantic Ocean and the Southern Ocean, suggesting that close faunal links exist between these areas. Three were first described from the North Pacific Ocean while others, including the three new species, are so far known only from the Southern Ocean. © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society , 2007, 151 , 219–251. 相似文献
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MAUREEN B. PETERS JULIE L. GLENN PAM SVETE CRIS HAGEN OLGA V. TSYUSKO PATRICIA DECOURSEY MLISSA LIEUTENANT‐GOSSELIN DANY GARANT TRAVIS C. GLENN 《Molecular ecology resources》2007,7(5):877-879
We isolated and characterized 16 microsatellite loci in the eastern chipmunk, Tamias striatus. The loci were screened across 25 individuals from one population and shown to be polymorphic with the number of alleles per locus ranging from two to 17. Polymorphic information content ranged from 0.212 to 0.887 and observed heterozygosity ranged from 0.200 to 0.960. Only two loci (Chip 10 and Chip 25) deviated from Hardy–Weinberg equilibrium. 相似文献
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OLGA CASTELLANI L. V. RIBEIRO J. F. FERNANDES 《The Journal of eukaryotic microbiology》1967,14(3):447-451
SYNOPSIS. A medium containing sodium and potassium chloride, phosphate buffer, glucose, calf serum, hemoglobin and lactalbumin hydrolysate permits some growth and differentiation of crithidiae into the metacyclic forms of Trypanosoma cruzi. The addition of ox liver infusion greatly enhances the growth promoting properties of this medium while making it very poor as far as differentiation is concerned. With dog heart infusion instead of ox liver, the medium is still good for growth but not much better for differentiation. If, however, the pH of the dog heart infusion medium is lowered from 7.2 to 6.7, it continues to be good for growth and becomes excellent for differentiation. Other factors were studied that stimulate or repress the rate of differentiation, such as preincubation at certain levels of temperature and the size and age of inocula. 相似文献
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Effects of plant diversity and structural complexity on parasitoid behaviour in a field experiment
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OLGA KOSTENKO MARK LAMMERS THOMAS KROON JEFFREY A. HARVEY MONIEK VAN GEEM T. MARTIJN BEZEMER 《Ecological Entomology》2015,40(6):748-758
1. In natural ecosystems, plants containing hosts for parasitoids are often embedded within heterogeneous plant communities. These plant communities surrounding host‐infested plants may influence the host‐finding ability of parasitoids. 2. A release‐recapture‐approach was used to examine whether the diversity and structural complexity of the community surrounding a host‐infested plant influences the aggregation behaviour of the leaf‐miner parasitoid Dacnusa sibirica Telenga and naturally occurring local leaf‐miner parasitoids. Released and locally present parasitoids were collected on potted Jacobaea vulgaris Gaertn.plants infested with the generalist leaf‐miner Chromatomyia syngenesiae Hardy. The plants were placed in experimentally established plant communities differing in plant diversity (1–9 species) and habitat complexity (bare ground, mown vegetation, and tall vegetation). Additionally, parasitoids were reared out from host mines on the trap plants. 3. Plant diversity did not influence the mean number of recaptured D. sibirica or captures of other locally present parasitoids but the number of recaptured parasitoids was influenced by habitat complexity. No D. sibirica parasitoids were recaptured in the bare ground plots or plots with mown vegetation. The mean number of recaptured D. sibirica generally increased with increasing complexity of the plant community, whereas locally present parasitoids were captured more frequently in communities with more bare ground. There was a unimodal relationship between the number of reared out parasitoids and diversity of the surrounding vegetation with the highest density of emerged parasitoids at intermediate diversity levels. 4. The present study adds to the thus far limited body of literature examining the aggregation behaviour of parasitoids in the field and suggests that the preference of parasitoids to aggregate in complex versus simple vegetation is association specific and thus depends on the parasitoid species as well as the identity of the plant community. 相似文献
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HEINER FLESSA REJ RODIONOV†‡ GEORG GUGGENBERGER‡ HANS FUCHS§ PAUL MAGDON§ OLGA SHIBISTOVA¶ GALINA ZRAZHEVSKAYA¶ NATALIA MIKHEYEVA¶ OLEG A. KASANSKY CHRISTIAN BLODAU 《Global Change Biology》2008,14(9):2040-2056
Terrestrial ecosystems in northern high latitudes exchange large amounts of methane (CH4) with the atmosphere. Climate warming could have a great impact on CH4 exchange, in particular in regions where degradation of permafrost is induced. In order to improve the understanding of the present and future methane dynamics in permafrost regions, we studied CH4 fluxes of typical landscape structures in a small catchment in the forest tundra ecotone in northern Siberia. Gas fluxes were measured using a closed‐chamber technique from August to November 2003 and from August 2006 to July 2007 on tree‐covered mineral soils with and without permafrost, on a frozen bog plateau, and on a thermokarst pond. For areal integration of the CH4 fluxes, we combined field observations and classification of functional landscape structures based on a high‐resolution Quickbird satellite image. All mineral soils were net sinks of atmospheric CH4. The magnitude of annual CH4 uptake was higher for soils without permafrost (1.19 kg CH4 ha−1 yr−1) than for soils with permafrost (0.37 kg CH4 ha−1 yr−1). In well‐drained soils, significant CH4 uptake occurred even after the onset of ground frost. Bog plateaux, which stored large amounts of frozen organic carbon, were also a net sink of atmospheric CH4 (0.38 kg CH4 ha−1 yr−1). Thermokarst ponds, which developed from permafrost collapse in bog plateaux, were hot spots of CH4 emission (approximately 200 kg CH4 ha−1 yr−1). Despite the low area coverage of thermokarst ponds (only 2.1% of the total catchment area), emissions from these sites resulted in a mean catchment CH4 emission of 3.8 kg CH4 ha−1 yr−1. Export of dissolved CH4 with stream water was insignificant. The results suggest that mineral soils and bog plateaux in this region will respond differently to increasing temperatures and associated permafrost degradation. Net uptake of atmospheric CH4 in mineral soils is expected to gradually increase with increasing active layer depth and soil drainage. Changes in bog plateaux will probably be much more rapid and drastic. Permafrost collapse in frozen bog plateaux would result in high CH4 emissions that act as positive feedback to climate warming. 相似文献
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Summary Responses of larvae of two rhizocephalan species to changes in seawater temperature and salinity were studied under laboratory conditions. Peltogasterella gracilis parasitizes the hermit crab Pagurus pectinatus, which occurs at stable salinity and gradually changing temperature in summer. Sacculina polygenea is a parasite of the crab Hemigrapsus sanguineus, which lives in the intertidal zone in summer where salinity and temperature can fluctuate during the day. The development of both species is comprised of five naupliar stages and the cyprid stage, and it was considered successful if more than 50% of the nauplii attained the cyprid stage. P. gracilis nauplii successfully developed at 12–20°C and 30–34‰, but at 22°C successful development occurred in a narrower salinity range (32–34‰). All nauplii died both at 25°C and in 26‰. S. polygenea nauplii successfully reached the cyprid stage at higher temperatures (18–25°C) and a wider salinity range (18–34‰) than P. gracilis nauplii, but at 12°C and 16‰ larval development of S. polygenea was suppressed. Under favorable conditions, naupliar development lasted 3.5 days in P. gracilis and 2–3 days in S. polygenea. The cyprids of both rhizocephalan species demonstrated a greater resistance to temperature and salinity changes than nauplii. However, P. gracilis cyprids were active in a narrower salinity range (16–34‰), as compared to S. polygenea cyprids (8–34‰). Under favorable conditions the cyprids of both species survived for 6 to 10 days. 相似文献
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