Cibois A.,Natural History Museum of Geneva |
Sheldon F.H.,Louisiana State University
Auk | Year: 2016
Jukema and colleagues published in The Auk a study dealing with geographic variation within the Pacific Golden-Plover (Pluvialis fulva). We highlight a taxonomic problem created unwittingly by the last sentence of their article, in which the authors suggest a new name for the Siberian population. © 2016 American Ornithologists' Union.
Weyeneth N.,Natural History Museum of Geneva |
Goodman S.M.,Field Museum of Natural History |
Ruedi M.,Natural History Museum of Geneva
Journal of Biogeography | Year: 2011
Aim- Three mechanisms have been proposed to explain the adaptive radiations and species diversifications of Madagascar's biota: the ecogeographical constraint, the riverine barrier and the micro-endemism models. On the intraspecific level, each model predicts different patterns of gene flow across the island's physical and ecological features. To evaluate these models, phylogeographical analyses were conducted on a widespread and endemic species of bat, Myotis goudoti (Vespertilionidae).Location- Madagascar.Methods- In order to reconstruct the phylogeographical history of M. goudoti, the mitochondrial D-loop and the cytochrome b gene were sequenced for 195 bats from 41 localities. Phylogenetic reconstructions and a minimum spanning tree were used to infer haplotype relationships. The effect of barriers on gene flow was evaluated using analyses of molecular variance and pairwise population differentiation. Mismatch distribution and coalescence-based estimates were conducted to infer the demographic history of M. goudoti.Results- The sequenced individuals showed 159 distinct D-loop haplotypes, most of them being unique to a single location. Populations were significantly structured (ΦST-=-0.170, P-<-0.001) across Madagascar, but only a minor part of the overall genetic variance was explained by any of the three models. Shared ancestry of lineages across most physical or ecological barriers was common, whereas the uncovered genetic differences between southern and central-northern populations were unexpected.Main conclusions- Major barriers predicted by the three biogeographical models do not explain the segregation of mitochondrial lineages of M. goudoti across Madagascar. This is not simply attributable to the high dispersal ability of this species, as populations are notably structured. The genetic contrast between southern and central-northern populations, separated by a zone of admixture, suggests that these areas currently support populations that expanded during the Late Pleistocene. This latitudinal differentiation of populations has been observed in less vagile animals, such as geckos and lemurs, suggesting that climate fluctuations of the Pleistocene had an impact across several groups and resulted in northern and southern refugia in Madagascar. © 2010 Blackwell Publishing Ltd.
Di Pierro S.,French National Center for Scientific Research |
Gnos E.,Natural History Museum of Geneva
American Mineralogist | Year: 2016
Hundred-micrometer-sized calcium-aluminum-silicates (CAS) inclusions occur in moissanite-4H, moissanite-15R, and moissanite-6H from Turkey. These inclusions commonly consist of tabular exsolution lamellae of two different minerals. By combined electron microprobe and Raman spectroscopy analysis, at least eight different, essentially Mg- and Fe-free Ca-Al-silicate or Al-silicate phases have been discerned. The most common phase is dmisteinbergite, a hexagonal modification of CaAl2Si2O8, occurring in association with lamellae of Cax(Al,Si)1-xO3 or Ca1-x(Al,Si)2+xO5 compositions. All three phases contain significant amounts of BaO (up to 2 mol% of celsiane component in dmisteinbergite), SrO, SO3, and light rare earth elements (LREE). In particular, Ca1-x(Al,Si)2+xO5 contains up to 2.1 wt% of LREE, 3.9 wt% of F, and significant traces of Cl, while it is also associated to osbornite (TiN). Pure ghelenite, Ca2Al2SiO7, and three additional compositions, namely CaAl4-xSixO7, Ca1-x(Al,Si)3+xO6, and Ca3-x(Al,Si)6+xO14 have been found, either occurring as single grains or forming exsolution lamellae. They also contain significant amounts of BaO, SrO, SO3, and LREE. One last intriguing phase is composed in average of 65.9 wt% SiO2, 17.4% Al2O3, 3.0% alkalis, 6.0% BaO, 2.0% CaO+MgO, 0.9% ZrO2, and up to 0.5% LREE. Dmisteinbergite and ghelenite show Raman peaks in very good agreement with literature data, Cax(Al,Si)1-xO3 shows main Raman modes at 416 and 1009 cm-1, Ca1-x(Al,Si)3+xO6 at 531 and 1579 cm-1 while Ca3-x(Al,Si)6+xO14 has a strong peak at 553 cm-1. CaAl4-xSixO7 shows a weak Raman pattern, while Ca1-x(Al,Si)2+xO5 has no detectable Raman modes. Since the association moissanite-CAS is thermodynamically not stable at ambient pressure and moissanite crystals hosting the CAS phases have δ13C values typical of deep-mantle origin, we interpret the CAS inclusions as partially retrogressed HP minerals. Striking analogies exist between observed CAS compositions and experimentally obtained HP-HT mineralogy. For instance, Cax(Al,Si)1-xO3 contains up to 25 mol% of Al2O3, which is considered as the upper limit of alumina solubility in Ca-perovskite. The study confirms that CAS phases are an important mantle depository for large ion lithophile elements (LILE) and LREE. © 2016 by Walter de Gruyter Berlin/Boston.
Ruedi M.,Natural History Museum of Geneva |
Biswas J.,National Cave Research and Protection Organization |
Csorba G.,Hungarian Natural History Museum
Revue Suisse de Zoologie | Year: 2012
The bat fauna of Meghalaya, north-eastern India, is very diverse but still improperly known. Recent field work revealed several previously unrecorded bats, especially in the southern and eastern hill ranges known as the Khasi and Jaintia Hills. We resolve here the systematic position of two Marina species that belong to the "swilla-group" and "cycloftis-group", respectively, using a combination of morphological and molecular characters. Both taxa proved to be morphologically and genetically distinct from any known species and are therefore described here as new species. So far, M. jaintiana sp. nov. has been found both in the Jaintia Hills of eastern Meghalaya, and in the Chin Hills of north-eastern Myanmar, while M. pluvialis sp. nov. is only known from the dense evergreen forests of the Khasi Hills, close to the Meghalaya border with Bangladesh. During the last few decades, these areas have suffered serious habitat degradation due to deforestation associated with mining activities, and both require urgent conservation measures to preserve their unique natural resources.
Zehtindjiev P.,Bulgarian Academy of Science |
Ivanova K.,Bulgarian Academy of Science |
Mariaux J.,Natural History Museum of Geneva |
Georgiev B.B.,Bulgarian Academy of Science
Parasitology Research | Year: 2013
A total of 76 birds belonging to 23 species and 14 families was examined for the presence of Plasmodium spp. and Haemoproteus spp. Birds were trapped at four localities in Gansu Province, China, in June-July 2011. DNA was isolated from blood samples and parasite detection, and identification was based on PCR assays and sequences of 479 bp of cyt b gene. The total prevalence of haemosporidians was 21.0 %. Haemoproteus spp. were detected in 14 birds (prevalence 18.4 %). The lineage CYAPIC1 from Cyanopica cyanus, Parus major, Passer montanus and Pyrrhocorax pyrrhocorax was new; it is genetically distinct and probably represents a new species of the genus Haemoproteus. Three lineages represented known species: RBS4 (from Lanius tephronotus), a lineage of Haemoproteus lanii; COLL2 (from Turdus mupinensis), a lineage of Haemoproteus pallidus and TURDUS2 (from Turdus rubrocanus), a lineage of Haemoproteus minutus. The lineage RBS5 (from Lanius cristatus and L. tephronotus) differs by 1.4 % from RBS4 and probably represents an intraspecific entity of H. lanii. The lineages TUCHR1 (recorded from T. mupinensis), WW1 (recorded from Upupa epops) and YWT2 (recorded from Motacilla flava) have not been linked to any known species for the moment. Only one bird was positive for Plasmodium (prevalence 1.4 %), i.e. P. major infected with the lineage GRW4 of Plasmodium relictum. The latter lineage has been considered by previous studies as typical for migratory birds and having transmission in tropical areas only; its record in a sedentary bird in China suggests its transmission in temperate latitudes. © 2013 Springer-Verlag Berlin Heidelberg.
Meister C.,Natural History Museum of Geneva |
Piuz A.,Natural History Museum of Geneva
Cretaceous Research | Year: 2013
The Cenomanian-Turonian ammonite biostratigraphical framework for the southern Tethys margin (North Africa, Middle East and the Arabian Peninsula) is becoming better understood. A first attempt at a synthetic range chart is presented, with 85 taxa and precise correlations for ammonites along a west-east transect from Morocco to Oman, inclusive of the Trans-Saharan Seaway as far south as northern Nigeria. On the basis of a critical review of ammonite taxonomy, 13 bioevents can be identified in the interval from the Late Cenomanian to the Early Turonian (c. 3.5myr) with each bioevent corresponding to a time interval of approximately 270,000 years, on average. They are consistent throughout several regions along the southern Tethys margin, though some gaps remain, at least at the stage boundary. These bioevents are correlated with the zonation defined for the stratotype (GSSP) of the base of the Turonian in the Western Interior (USA). The paleobiogeographic distribution of ammonites reveals some endemism but the predominant picture is that of a homogeneous fauna throughout the area, even though distinct Boreal and Western Tethys (Atlantic domain) marine influences are evident. An interpretation of the evolution of conch morphology and ornamentation through the zones of the Late Cenomanian-Early Turonian is proposed. © 2013 Elsevier Ltd.
Schuchert P.,Natural History Museum of Geneva
Molecular Phylogenetics and Evolution | Year: 2014
The marine hydroid Plumularia setacea has a near-cosmopolitan distribution. As in other sessile invertebrates with limited dispersal abilities, the wide distribution could also be a taxonomic artefact and the species might in fact be a complex of sibling species. To investigate this, a set of worldwide samples of P. setacea and several closely related species was examined using the mitochondrial markers 16S and COI, as well as the nuclear marker ITS. The results suggest an even higher degree of genetic diversity than expected. Almost all sampled regions had only private haplotypes and the resulting trees split into a multitude of geographically delimited lineages, this both for the mitochondrial and nuclear markers. In the framework of a genealogical species concept, these lineages would qualify as cryptic species. Using alternative species concepts, the results could be reconciled with traditional taxonomy by regarding P. setacea as a single species with an extensive population subdivision. A rapid molecular clock, limited dispersal abilities, and localized clonal propagation are likely the factors that explain the high but dispersed genetic diversity within this species. © 2014 Elsevier Inc.
Meister C.,Natural History Museum of Geneva |
Schlogl J.,Comenius University
Neues Jahrbuch fur Geologie und Palaontologie - Abhandlungen | Year: 2011
Among the rich ammonite fauna of the condensed section of Chtelnica (Western Carpathians) 33 species are discussed for the Phylloceratoidea [Phylloceratidae (5), Juraphyllitidae (5)], Lytoceratoidea [Pleuroacanthidae (6), Lytoceratidae (4)] and Schlotheimiidae (13). Five species are new: Lytotropites compressus, Lytoceras perplexum, Angulaticeras (Sulciferites) helvii, Angulaticeras (Sulciferites) chtelnicaense, and Angulaticeras (Angulaticeras) spinosus n. sp. The latter is a key taxon to the understanding of the origin of the Phricodoceratidae. The age of the fauna covers a large period in the Sinemurian from the Bucklandi Zone up to the Turneri and/or partim Obtusum Zones. © 2011 Schweizerbart'sche Verlagsbuchhandlung, Stuttgart, Germany.
Benyoucef M.,University of Mascara |
Meister C.,Natural History Museum of Geneva
Cretaceous Research | Year: 2015
Fifteen stratigraphic sections located in different parts of the Guir basin (Southwest Algeria) have been measured bed-by-bed and sampled in great detail, to study the stratigraphy, describe and interpret the facies and characterize the depositional environment of the Cenomanian-Turonian succession. Based on their stratigraphic ranges, lithofacies, regional distributions and depositional settings, the Cenomanian-Turonian succession is subdivided into three lithostratigraphic formations that are bounded by a regional scale discontinuity: the "Grès rouges" Formation attributed to the lower Cenomanian; the "Marnes à gypse inférieures" Formation assigned to the lower-middle Cenomanian and the "Calcaires de Sidi Mohamed Ben Bouziane" Formation placed in the upper Cenomanian-lower Turonian. Analyses of litho-, bio-, and microfacies resulted in the recognition of 25 facies types for this succession. These facies types have been grouped into seven facies associations (AF1 to AF7). The facies represented range from clastic, to evaporitic to carbonate, and were deposited in four major depositional environments: fluvial, siliciclastic costal, sabkha and homoclinal carbonate ramp settings. The main factors controlling depositional environments were eustatic sea-level fluctuations combined with environmental influences such as autochthonous carbonate productivity and siliciclastic supply. © 2014 Elsevier Ltd.
Meister C.,Natural History Museum of Geneva
Stratigraphy | Year: 2010
The present paper is an inventory of the biostratigraphical ammonite data at the boundaries of the Sinemurian and Pliensbachian Stages and of the Lower-Upper Pliensbachian Substages. Sinemurian and Pliensbachian Stages belong to the Early Jurassic (Lias) and the age of their boundary is 190 m.y. following the last version of the Geologic Time scale compiled by Walker and Geissman (2009). Since 2006, the Global boundary Stratotype Section and Point (GSSP) for the base of the Pliensbachian Stage is formally defined at Wine Haven in Yorkshire Coast (UK). This level coincides with the ammonite association Bifericeras donovani Dommergues and Meister and Apoderoceras sp. which define the base of the Taylori Sub- chronozone of the Jamesoni Chronozone. For the Lower-Upper Pliensbachian boundary, estimated at 186.5 m.y. there is no formal definition with a GSSP until now. Several options remain open as well in the Euroboreal Domain (Hebrides, Yorshire, Dorset in UK, Causses Basin in France, Cordillera Iberica in Spain, Lusitanian Basin in Portugal) as in the Tethyan Domain (Subbeticas in Spain, Apennines in Italy, Bakony in Hungary). Worldwide correlations (Euroboreal, Tethyan and East Pacific Domains) at these boundaries are proposed based on ammonites after critical review of their taxonomy and biostratigraphy. Indeed for Lower Jurassic, ammonites represent the best fossil group for precise biostratigraphy and correlation and that is why the standard chronostratigraphic framework (at zonal level) has been based on them since Oppel (1856-58).