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191.
CHRISTIAN SCHMIDT 《Zoological Journal of the Linnean Society》2007,151(S1):1-339
The species of Scleropactidae from America are revised and redescribed. A phylogeny hypothesis based on an analysis of morphological characters is presented. The genera are redefined and the generic placement of several species is corrected. The Neotropical Scleropactidae include Colomboscia , Scleropactes , Circoniscus , Neosanfilippia , Sphaeroniscus , Richardsoniscus , Spherarmadillo , Colomboniscus , Amazoniscus and Protosphaeroniscus . The genus Chileoniscus is excluded from the Scleropactidae. Sphaerobathytropa is excluded from the Scleropactidae and its previous record from Argentina is revealed to be erroneous. Synuropus is revalidated and excluded from the Scleropactidae. The following new genera are introduced: Scleropactoides gen. nov. , Globopactes gen. nov. , Caecopactes gen. nov. , and Troglopactes gen. nov. Thirteen species are described as new: Caecopactes minimus sp. nov. , Colomboscia parva sp. nov. , Globopactes falconensis sp. nov. , Globopactes hispidus sp. nov. , Globopactes meridae sp. nov. , Scleropactes cotopaxii sp. nov. , Scleropactes ecuadoriensis sp. nov. , Scleropactes pululahua sp. nov. , Scleropactoides curvatus sp. nov. , Circoniscus hirsutus sp. nov. , Sphaeroniscus quintus sp. nov. , Spherarmadillo nebulosus sp. nov. , and Chileoniscus armadillidioides sp. nov. Identification keys to all species are provided. © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society , 2007, 151 (Suppl. 1), 1–339. 相似文献
192.
Abstract: New petrosal bones, assigned to Pucadelphys and Andinodelphys , from the Lower Paleocene of Tiupampa, Bolivia, are described. These remains provide new information on the anatomy of the ear region of these taxa. The re-examination of characters from the petrosal and basicranium shed light on the phylogenetic relationships of the three Tiupampan genera known from complete cranial remains (i.e. Mayulestes , Pucadelphys and Andinodelphys ). The combination of dental, general cranial and basicranial characters led to two alternative hypotheses. The first is that borhyaenoids (including Mayulestes ) are nested within Notometatheria. Pucadelphyds (i.e. Pucadelphys and Andinodelphys ) are the sister group of a clade comprising MHNC 8369 (one isolated petrosal from Tiupampa) and Marsupialia. The second favours the paraphyly of 'borhyaenoids' (i.e. the exclusion of Mayulestes from borhyaenoids) and the polyphyly of 'Notometatheria'. In this case, Mayulestes and borhyaenids represent the stem group of a clade including Asiatic, American and Australian metatherians. This analysis of combined datasets (dental, general cranial and basicranial) highlighted contradictory information in the dental and cranial characters, serving to emphasize that in a large anatomical complex like an entire skull mosaic evolution of the characters is likely. 相似文献
193.
Systematics and evolution of Velloziaceae, with special reference to sieve-element plastids and rbcL sequence data 总被引:3,自引:0,他引:3
194.
Community structure or function: effects of environmental stress on benthic macroinvertebrates at different spatial scales 总被引:4,自引:0,他引:4
1. This study investigated the relation of benthic macroinvertebrates to environmental gradients in Central European lowland rivers. Taxonomic structure (taxa) and functional composition (metrics) were related to gradients at four different spatial scales (ecoregion, catchment, reach and site). The environmental variables at the catchment‐, reach‐ and site scales reflected the intensity of human impact: catchment and floodplain land use, riparian and floodplain degradation, flow regulation and river bank and bed modification. 2. Field surveys and GIS yielded 130 parameters characterising the hydromorphology and land use of 75 river sections in Sweden, the Netherlands, Germany and Poland. Two hundred and forty‐four macroinvertebrate taxa and 84 derived community metrics and biotic indices such as functional guilds, diversity and composition measures were included in the analysis. 3. Canonical Correspondence Analysis (CCA) and Redundancy Analysis (RDA) showed that hydromorphological and land use variables explained 11.4%, 22.1% and 15.8% of the taxa variance at the catchment (‘macro’), reach (‘meso’) and site (‘micro’) scales, respectively, compared with 14.9%, 33.2% and 21.5% of the variance associated with the derived metrics. Ecoregion and season accounted for 10.9% and 20.5% of the variance of the taxonomic structure and functional composition, respectively. 4. Partial CCA (pCCA) and RDA (pRDA) showed that the unique variance explained was slightly higher for taxa than for metrics. By contrast, the joint variance explained for metrics was much higher at all spatial scales and largest at the reach scale. Environmental variables explained 46.8% of metric variance and 32.4% of taxonomic structure. 5. Canonical Correspondence Analysis and RDA identified clear environmental gradients along the two main ordination axes, namely, land use and hydromorphological degradation. The impact of catchment land use on benthic macroinvertebrates was mainly revealed by the proportion of urban areas. At the reach scale, riparian and floodplain attributes (bank fixation, riparian wooded vegetation, shading) and the proportion of large woody debris were strong predictors of the taxonomic structure and functional composition of benthic macroinvertebrates. At the site scale, artificial substrata indicated human impact, particularly the proportion of macro‐ and mesolithal used for bank enforcement (rip–rap). 6. Our study revealed the importance of benthic macroinvertebrate functional measures (functional guilds, composition and abundance measures, sensitivity and tolerance measures, diversity measures) for detecting the impact of hydromorphological stress at different spatial scales. 相似文献
195.
Tissue localization of u.v.-B-screening pigments and of chalcone synthase mRNA in needles of Scots pine seedlings 总被引:1,自引:0,他引:1
196.
THE WATER RELATIONS OF STAPHYLOCOCCI AND MICROCOCCI 总被引:3,自引:3,他引:0
197.
CHRISTOPHER B. ANDERSON JUAN L. CELIS‐DIEZ BARBARA J. BOND GUILLERMO MARTÍNEZ PASTUR CHRISTIAN LITTLE JUAN J. ARMESTO CLAUDIO GHERSA AMY AUSTIN TOMAS SCHLICHTER ANTONIO LARA MARTIN CARMONA ENRIQUE J. CHANETON JULIO R. GUTIERREZ RICARDO ROZZI KRISTIN VANDERBILT GUILLERMO OYARCE ROBERTO J. FERNÁNDEZ 《Austral ecology》2012,37(5):529-536
198.
JENNIFER M. WALKER ARTHUR E. BOGAN ELSIE A. BONFIGLIO DAVID C. CAMPBELL ALAN D. CHRISTIAN JASON P. CUROLE JOHN L. HARRIS RUDY J. WOJTECKI WALTER R. HOEH 《Molecular ecology resources》2007,7(3):489-491
Freshwater bivalves in the superfamily Unionoidea possess distinct male (M)‐ and female (F)‐transmitted mitochondrial DNA (mtDNA). The former evolves independently of and at a significantly faster rate than the latter. Thus, population genetic and phylogenetic analyses of M sequences facilitate the generation of independent estimates of genetic variation and evolutionary relationships which are often more robust than those provided by analyses of F sequences alone. However, M mtDNA's rapid substitution rate often renders polymerase chain reaction (PCR) amplification difficult with ‘universal’ primers. Herein, we report on three pairs of PCR primers that consistently amplify the hypervariable M COII‐COI gene junction region in 25 bivalve genera (Unionoidea: Ambleminae). 相似文献
199.
Abstract Normanbya normanbyi (W. Hill) L. H. Bailey (Arecaceae) is a monoecious, arborescent palm with a very small distribution area within the Daintree rainforest in north‐eastern Australia. Our 2‐year study was focused on the reproductive phenology at the individual and population level. At the population level flowering peaked in the dry season, whereas fruiting was confined to the wet season. Each palm can bear up to three inflorescences/infructescences at the same time. Flowering of each inflorescence is separated from each other by a couple of weeks. A single inflorescence consists of about 1900 staminate and 800 pistillate flowers. The flowering of N. normanbyi is protandrous with a staminate phase lasting 40 days and a pistillate phase of approximately 2 weeks. Between both phases is a non‐flowering phase of about 9 days. Fruit ripening takes 21 weeks, with an average of about 280 ripe fruit per tree. Comparison of three study plots revealed a moderate synchrony of flowering and fruiting initiation in this species of palm. The male phase of flowering shows a higher degree of synchrony than the female phase at the population level. Seasonal regularity of flowering and fruiting peaks appears to be predictable. The general flowering and fruiting phenology of N. normanbyi follows a subannual pattern with a strong tendency towards a continual pattern. 相似文献
200.
ANNE TOTET SOPHIE LATOUCHE HYACINTHE DUWAT ELINE MAGOIS PHILIPPE LACUBE JEAN-CLAUDE PAUTARD JEAN-LUC SCHMIT VINCENT JOUNIEAUX PATRICIA ROUX CHRISTIAN RACCURT GILLES NEVEZ 《The Journal of eukaryotic microbiology》2003,50(S1):670-689
ABSTRACT. Pneumocystis jirovecii ITS and DHPS genotypes were identified in 3 patient groups developing diverse forms of P. jirovecii infections: 13 patients with Pneumocystis pneumonia, 8 patients merely colonized by the fungus, and 19 immunocompetent infants with bronchiolitis developing mild P. jirovecii infection. Common P. jirovecii genotypes were found in the 3 patient groups, suggesting that common sources of P. jirovecii were involved in the fungus acquisition, and that transmission cycles of P. jirovecii infections in these patient groups are not independent. Parasitized patients, whatever the form of parasitism they present, may he part of a common reservoir for P. jirovecii. 相似文献