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1.
2.
《Mycological Research》2007,111(2):213-223
The genetic structure and occurrence of mating types and forms of Pyrenophora teres, the causal agent of net blotch on barley, was studied among 278 isolates collected from the northern hemisphere and from Australia. Genetic differentiation was high (FCT 0.238, P = 0.002) between P. teres f. teres (PTT) isolates originating from Northern Europe, North America, Russia and Australia. The P. teres population in Australia was clearly divided into two subgroups (FCT 0.793, P < 0.001) according to the form identity: PTT and P. teres f. maculata (PTM), with the PTT samples showing a greater degree of differentiation (FST 0.573, P < 0.001) among Australian states than the PTM samples (FCT 0.219, P < 0.001). No differentiation was found among locations within Australian states. Both mating types (MAT1 and MAT2) were equally common (1:1) in several locations in Australia and in Finland. The only exception was Krasnodar, Russia, where only MAT2 was identified. Our results show that the prevalence of sexual reproduction, occurrence of forms of P. teres, and genetic differentiation between geographical regions are highly variable. The paper discusses the various effects and outcomes of population selection in Australia and in the northern barley growing regions.  相似文献   

3.
Silurian trilobites of Ludlow and P?ídolí age are described from sections in southern Uzbekistan and from adjacent parts of Tajikistan. They belong to 22 species (10 named and 12 under open nomenclature) distributed among 13 genera belonging to the families Proetidae, Tropidocoryphidae, Aulacopleuridae, Scharyiidae, Cheiruridae, Encrinuridae and Odontopleuridae. The following new species are described: Interproetus pentaxus, Paleodechenella turkestanica, P. zaaminicus, Cromus tamchii and Leonaspis nuratensis. The generic associations from the mid Ludlow bear a striking resemblance to coeval ones from Bohemia, and include genera otherwise known only from that region or from adjacent parts of central Europe. The trilobite faunas from the late Ludlow and P?ídolí series are much less diverse and are dominated by genera of the Warburgellinae (Tropidocoryphidae), which include one species common to Vaigatch Island in the Russian Arctic, and Podolia, Ukraine. The closest links of the diverse central Asian mid Ludlow faunas are therefore to central Europe, whilst the sparser younger Ludlow and P?ídolí faunas, such as they are, suggest closer links to Baltica.  相似文献   

4.
《Comptes Rendus Palevol》2013,12(4):191-202
We describe here “miacid” taxa from the Early Eocene Paris Basin locality of Le Quesnoy (Oise, France). We describe the new species Vassacyon taxidiotis, the first European record of this genus. The other “miacids” identified from Le Quesnoy are Miacis latouri and Gracilocyon solei. The P4 of G. solei is described here for the first time. Its morphology (e.g., wide protocone, short postmetacrista) supports a close relationship with Miacis rundlei from Abbey Wood (MP8 + 9, England). The latter species is therefore classified as Gracilocyon rundlei. Three new tooth positions are known for Miacis latouri: P4, p4 and m2. They support its reference to Miacis. These specimens imply that the European species is more basal than the North American species. The fauna from Le Quesnoy shares with Dormaal the presence of Miacis latouri and Gracilocyon solei, but the “miacid” fauna from Le Quesnoy also contains Vassacyon taxidiotis. The presence in Le Quesnoy of the two former taxa supports a reference to MP7 level of the French locality. The presence of three distinct genera in European localities show that the “Miacidae” were diversified in Europe, as previously observed in North America. The genera Gracilocyon, Miacis, and Vassacyon probably dispersed from Europe to North America during the Palaeocene/Eocene boundary.  相似文献   

5.
《Fungal biology》2019,123(11):811-823
Fungal plant pathogens are increasingly recognised as being among the most effective and safe agents in classical weed biological control programs worldwide. Suitability of the rust fungus P. rapipes as a classical biological control agent for Lycium ferocissimum (African boxthorn) in Australia was assessed using a streamlined agent selection framework. Studies with P. rapipes were undertaken to elucidate its life cycle, confirm its taxonomic placement and determine its pathogenicity to L. ferocissimum and seven closely-related Solanaceae species that occur in Australia. Field surveys in the native range of South Africa, experiments in a containment facility in Australia and DNA sequencing confirmed that P. rapipes is macrocyclic and autoecious, producing all five spore stages on L. ferocissimum. The stages not previously encountered, spermogonia and aecia, are described. Sequencing also confirmed that P. rapipes is sister to Puccinia afra, in the ‘Old World Lineage’ of Puccinia species on Lycieae. Two purified isolates of the fungus, representing the Eastern and Western Cape distributions of P. rapipes in South Africa, were cultured in the containment facility for use in pathogenicity testing. L. ferocissimum and all of the Lycium species of Eurasian origin tested ‒ Lycium barbarum (goji berry), Lycium chinense (goji berry ‘chinense’) and Lycium ruthenicum (black goji berry) – were susceptible to both isolates of P. rapipes. The Australian native L. australe and three more distantly related species in different genera tested were resistant to both isolates. The isolate from the Western Cape was significantly more pathogenic on L. ferocissimum from Australia, than the Eastern Cape isolate. Our results indicate that P. rapipes may be sufficiently host specific to pursue as a biological control agent in an Australian context, should regulators be willing to accept damage to the Eurasian goji berries being grown, albeit to a limited extent, in Australia.  相似文献   

6.
《Palaeoworld》2020,29(1):47-65
The graptolite fauna of the Mandalay Region, Myanmar, is poorly known. In this paper, 13 species in the genera Avitograptus, Korenograptus, Metabolograptus, Neodiplograptus and Normalograptus are described from the uppermost Ordovician strata of the area. Two of these species, Korenograptus selectus X. Chen n. sp. and Neodiplograptus mandalayensis X. Chen n. sp., are new. On the basis of the graptolite faunas, a biostratigraphic scheme for the uppermost Ordovician (Hirnantian: Metabolograptus extraordinarius Biozone and Metabolograptus? persculptus Biozone?) strata in this area is erected.  相似文献   

7.
The glider genus Petaurus comprises a group of arboreal and nocturnal marsupial species from New Guinea and Australia. Molecular data were generated in order to examine phylogenetic relationships among species within the genus and explore the time-scale of diversification and biogeographic history of the genus in Australia and New Guinea. All known species and subspecies of Petaurus (with the exception of P. biacensis) were sequenced for two mitochondrial genes (ND2 and ND4) and one nuclear marker (omega-globin gene). Phylogenetic analyses confirmed the monophyly of the genus relative to other petaurids and showed a sister relationship of P. australis to the rest of Petaurus. The analyses revealed that currently recognised species of Petaurus formed distinct mitochondrial DNA (mtDNA) clades. Considerable mtDNA diversity and seven distinct clades were identified within the species P. breviceps, with the distribution of each clade showing no correspondence with the distributional limits of known subspecies. Molecular dating analyses using BEAST suggested an early to mid-Miocene origin (18–24 mya) for the genus. Ancestral area reconstructions, using BayesTraits, did not resolve the location for the centre of origin of Petaurus, but provided evidence for at least one dispersal event from New Guinea to Australia that led to the evolution of extant Australian populations of P. breviceps, P. norfolcensis and P. gracilis. The timing of this dispersal event appears to pre-date the Pleistocene, adding to the growing number of studies that suggest faunal connections occurred between Australia and New Guinea in the Late Miocene to Pliocene period.  相似文献   

8.
《Comptes Rendus Palevol》2019,18(7):747-763
Glyptosaurine lizards (Glyptosaurinae, Anguidae) are an extinct group of heavily armored lizards known from North America, Europe and Asia. Glyptosaurine lizards, taxa that possess fully developed tuberculated dermal armor, appear to have been established in North America by late early Puercan time (To3). “Proxestops,” a taxon distinguished by a combination of vermiculate and tuberculated osteoderm sculpturing, is considered to be a non-glyptosaurine, a sister taxon of the Glyptosaurinae. Known from only fragmentary remains, its wide chronostratigraphic distribution suggests that “Proxestops” is a form genus that, in all probability, represents more than one taxon, that ranges from the middle Paleocene to the early Eocene of North America. Moreover, the taxa Odaxosaurus piger, Parodaxosaurus sanjuanensis and “Proxestops” are best considered “proto-glyptosaurines”. “Melanosaurins” and glyptosaurins were well-established by the early Eocene, especially in North America, and are here documented by their type species and chronostratigraphic levels. Both tribes are present in Europe (MP7), too, but the record is not as estensive as that of North America. The North American taxon Gaultia silvaticus (Wa0) is transitional between a “melanosaurin” and glyptosaurin. Because it lacks the well-defined hexagonal osteoderms that characterize the Glyptosaurini, it is removed from that group and considered to be a “melanosaurin”. The “melanosaurin” taxon “Xestopssavagei (Wa4–Wa6) cannot be referred to Xestops (Br2) based on non-corresponding elements and because superficial similarity does not justify assignment to this taxon. Arpadosaurus sepulchralis (Wa6?), whose holotype is a fragmentary right frontal, is considered a subjective junior synonym of A. gazinorum, based on minor differences in the epidermal scale pattern that probably represent individual variation. “Glyptosaurusagmodon (Wa6?), based on a partial right maxilla, cannot be referred to Glyptosaurus (sensu stricto), and the material upon which this taxon is based bears strong resemblance to material identified as cf. “?Paraglyptosaurusyatkolai (Wa5–Wa6). “Glyptosaurusrhodinos (Wa5) is based on an incomplete parietal, and its reference to Glyptosaurus is considered problematic. Eoglyptosaurus donohoei (Wa7) is probably valid and is re-established here. Glyptosaurus (sensu stricto) is known solely from the middle Eocene (Br2) by G. sylvestris. Dimetoposaurus wyomingensis (Br3) is removed from Xestops vagans because its synonymy was based on superficial similarities. Helodermoides tuberculatus, the largest and last glyptosaurin (Ch3), is restricted to the Chadronian of North America. Only the “melanosaurin” Peltosaurus granulosus (Or2–Or3), which includes the species P. abbotti, seems to have crossed the Eocene-Oligocene boundary, and appears to be largely restricted to the Orellan, but extended into the Arikareean. European glyptosaurines are also represented by both glyptosaurins and “melanosaurins” early in the Eocene (MP7). Placosauriops-like “melanosaurins” are known from Dormaal (MP7), and the glyptosaurin taxon?Placosaurus ragei occurs at the same level. “Placosauriops abderhaldeni” has been identified from the Grube Messel (MP11), but this assignment remains dubious because the species has not been adequately diagnosed, and the holotype species is from the Geiseltal (MP13), which is some 4.5 million years younger. Placosauriops weigelti (MP13) is the only valid species of this genus. Paraxestops stehlini (MP14) is not referable to the North American taxon Xestops, and its relationship to Placosauriops has not been studied. The late Eocene glyptosaurins Placosaurus estesi (MP17) and P. rugosus (MP18) are the last glyptosaurines known from Europe and appear to have gone extinct at the Eocene-Oligocene boundary, casulties perhaps of the “Grande Coupure”. Asian glyptosaurines are known solely from one species, Stenoplacosaurus mongoliensis, from the middle Eocene (Sharamurunian) of China. Glyptosaurines most likely originated in North America, diversified by late Paleocene time, and rapidly spread across the North Atlantic into Europe by the early Eocene. Both “melanosaurins” and glyptosaurins took a foothold in Europe by the early Neustrian, but the glyptosaurins, aside from one occurrence (Dormaal, MP7), were conspicuously absent for most of Neustrian through early Robiacian time. In North America, glyptosaurins diversified during the early and middle Eocene, while in Europe small “melanosaurins” were a prominent part of the paleoherpetofauna, and glyptosaurins are unknown for most of the Neustrian through the Geiseltalian, in both the fossilferous Lagerstätten of Messel and Geiseltal. Stenoplacosaurus is the only known glyptosaurin glyptosaurine from Asia, and its abrupt appearance during the late Eocene suggests the possiblity of a Beringian dispersal from North America into Asia.  相似文献   

9.
Temperate species of Hypomyces and Cladobotryum that produce the red pigment aurofusarin are common on agaricoid and polyporoid basidiomata of species from five orders of Agaricomycetes. Several cause cobweb disease of commercially cultivated mushrooms resulting in serious losses. We sequenced rpb1, rpb2, tef1, and FG1093 regions in 90 wild strains and 30 strains from mushroom farms, isolated from Europe, North America, Africa, Asia, Australia, and New Zealand. Multigene analyses support the distinctness of five species but reveal Hypomyces rosellus to be paraphyletic, comprising several cryptic lineages. Hypomyces rosellus s. str. is characterised by wide dispersal and gene flow across Eurasia but does not occur in North America. Instead, the lineages from the West and the East Coast appear distinct, having given rise to species inhabiting the Southern Hemisphere. Our results reveal wide misuse of the name H. rosellus, especially for cobweb isolates. The majority of these belong to Hypomyces odoratus, including a weakly supported group of fungicide-resistant strains from Europe and North America sharing identical sequence data. New collections are presented for Cladobotryum rubrobrunnescens and Cladobotryum tenue as well as Cladobotryum multiseptatum and Hypomyces dactylarioides, all previously known only from their type material. The former species pair occurs in Europe and the latter in Australia and New Zealand. Separate lineages appear to be maintained by geographic isolation in North America and temperate Australasia but by host specialisation in the species occurring sympatrically in Europe and Asia. Both specialist and generalist host use strategies have evolved in the group. Although teleomorphs are known in most of the species and unnamed lineages, analyses of the five-gene regions suggest the prevalence of clonal reproduction in H. odoratus. This can be the reason for its success in mushroom farms, also facilitating the spread of fungicide resistance. While tef1 and rpb2 can be recommended for species delimitation, low variation, not exceeding 1 % in the whole ingroup, impeaches the use of ITS as a barcoding gene region in this group of fungi.  相似文献   

10.
11.
Indigenous to Europe, the blackberry rust fungus Phragmidium violaceum was introduced to Australia and subsequently appeared in New Zealand, with the most recent authorised introductions to Australia specifically for the biological control of European blackberry. Markers for ‘selective amplification of microsatellite polymorphic loci’ (SAMPL) were developed for studying the population genetics of P. violaceum. Modification of one of the two SAMPL primers with a HaeIII adapter (H) revealed significantly greater levels of genetic variation than primers used to generate AFLPs, the latter revealing little or no variation among 25 Australasian and 19 European isolates of P. violaceum. SAMPL was used to describe genetic variation among these 44 isolates of P. violaceum from 51 loci generated using primer pairs (GACA)4 + H–G and R1 + H–G. The European isolates were more diverse than Australasian isolates, with 37 and 22 % polymorphic loci, respectively. Cluster analysis revealed geographic clades, with Australasian isolates forming one cluster separated from two clusters comprising the European isolates. However, low bootstrap support at these clades suggested that Australian isolates had not differentiated significantly from European isolates since the first record of P. violaceum in Australia in 1984. In general, the results support two hypotheses. First, that the population of P. violaceum in Australia was founded from a subset of individuals originating from Europe. Second, that P. violaceum in New Zealand originated from the Australian population of P. violaceum, probably by wind dispersal of urediniospores across the Tasman Sea. The application of SAMPL markers to the current biological control programme for European blackberry is discussed.  相似文献   

12.
Species belonging to the potentially harmful diatom genus Pseudo‐nitzschia, isolated from 16 localities (31 sampling events) in the coastal waters of south‐eastern Australia, were examined. Clonal isolates were characterized by (i) light and transmission electron microscopy; (ii) phylogenies, based on sequencing of nuclear‐encoded ribosomal deoxyribonucleic acid (rDNA) regions and, (iii) domoic acid (DA) production as measured by liquid chromatography–mass spectrometry (LC‐MS/MS). Ten taxa were unequivocally confirmed as Pseudo‐nitzschia americana, P. arenysensis, P. calliantha, P. cuspidata, P. fraudulenta, P. hasleana, P. micropora, P. multiseries, P. multistriata, and P. pungens. An updated taxonomic key for south‐eastern Australian Pseudo‐nitzschia is presented. The occurrence of two toxigenic species, P. multistriata (maximum concentration 11 pg DA per cell) and P. cuspidata (25.4 pg DA per cell), was documented for the first time in Australia. The Australian strains of P. multiseries, a consistent producer of DA in strains throughout the world, were nontoxic. Data from 5,888 water samples, collected from 31 oyster‐growing estuaries (2,000 km coastline) from 2005 to 2009, revealed 310 regulatory exceedances for “Total Pseudo‐nitzschia,” resulting in six toxic episodes. Further examination of high‐risk estuaries revealed that the “P. seriata group” had highest cell densities in the austral summer, autumn, or spring (species dependent), and lowest cell densities in the austral winter, while the “P. delicatissima group” had highest in winter and spring.  相似文献   

13.
《Comptes Rendus Palevol》2013,12(2):101-113
New remains of felid jaws and teeth are described from several localities of the local stratigraphic series of Abocador de Can Mata (ca. 11.9 to 11.6 Ma, Middle Miocene; Vallès-Penedès Basin, Catalonia, Spain). Three different taxa are identified: Styriofelis turnauensis, Pseudaelurus romieviensis and Pseudaelurus quadridentatus. The described remains of P. romieviensis enable extending considerably the chronological range of this species in the Iberian Peninsula, in agreement with its record in the rest of Europe. Moreover, it is shown for the first time that P. romieviensis may possess a p2. The presence of this tooth therefore does not constitue a valid diagnostic feature to distinguish P. romieviensis from P. quadridentatus.  相似文献   

14.
POTAMOPYRGUS ANTIPODARUM--A MOLLUSCAN COLONISER OF EUROPE AND AUSTRALIA   总被引:1,自引:0,他引:1  
The hydrobiid gastropod genus Potamopyrgus is shown to be representedin Australia by the New Zealand species P. antipodarum (Gray).It is widely distributed in south eastern Australia and Tasmaniafollowing its introduction about the middle of the last century.The Australian populations of Potamopyrgus were known, incorrectly,as P. niger, because of a misinterpretation of Paludina nigraQuoy & Gai-mard, 1835. Paludina nigra, here placed in thegenus Fluvidona, is redescribed and a neotype designated. Potamopyrgusantipodarum has also been introduced to Europe, where it isknown as P. jenkinsi (Smith) (Received 19 August 1987; accepted 16 December 1987)  相似文献   

15.
The space of Devonian time considered in this paper corresponds to the uppermost part of the Famennian or the latest Famennian as a fourfold subdivision of the stage, usually called by many authors Strunian in neritic facies and Wocklumeria Stufe or Wocklumian in pelagic facies. Here, we examine the biostratigraphical value of certain brachiopod genera and species as bio-markers of the uppermost Famennian throughout the world (Europe, the former USSR, Middle East, Asia, North America, North Africa, and Australia). We have focused our study for species which stratigraphical range has been firmly established in correlation with the conodont biozones (Upper expansa, Early, Middle and Late praesulcata), the ammonoid biozones (do VI = “Wocklumeria Stufe”), or the foraminifera biozones (kobeitusana Zone). Other data for which the stratigraphical range is not based on standard biozonation are provided in the annex. The brachiopod bio-markers discussed in this paper belong to 14 Productidina genera (Acanthatia, Araksalosia, Ericiata, Hamlingella, Mesoplica, Nigerinoplica, Orbinaria, Ovatia, Rugauris, Semiproductus, Sentosia, Spinocarinifera, Steinhagella, Whidbornella), 7 Rhynchonellida genera (Araratella, Centrorhynchus, Hadyrhyncha, Megalopterorhynchus, Novaplatirostrum, Rozmanaria, Tchanakhtchirostrum), 13 Spiriferida genera (Brachythyris, Cyrtospirifer, Dichospirifer, Eochoristites, Imbrexia, Parallelora, Prospira, Rigauxia, Sphenospira, Tenisia, Toryniferella, Tylothyris, Voiseyella) and one Spiriferinida genus (Syringothyris). Other orders have not been studied in this paper. The main features of the uppermost Famennian brachiopod taxa represented in this paper are commented. All these taxa are listed as completely as possible throughout the world (with complements in the annex). A quick summary of the geographic distribution of the more represented taxa is given in conclusion.  相似文献   

16.
17.
《Geobios》2014,47(6):389-401
The conodont faunas of Tournaisian shallow-water carbonates from central Guangxi are described mainly for biostratigraphic purposes. A complete series of samples was collected from the Long’an and Du’an formations in the Long’an section. These formations are characterized by lime-mudstone, skeletal and peloidal wackestone, packstone and grainstone with typical shallow-water biota. Overall, these samples produced 809 identifiable Pl elements, belonging to 50 species in 11 genera, of which one species and one subspecies are new. The fauna enables the establishment of seven biozones (in ascending order): Polygnathus spicatus, Siphonodella homosimplex, S. sinensis, S. dasaibaensis, Polygnathus communis carina Acme, Gnathodus cuneiformis, and P. communis porcatus zones. Based on these new collections from central Guangxi and on data from the literature, a conflated Tournaisian conodont zonation is proposed for shallow-water successions in South China. Most of the conodont zones correlate well with their counterparts recognized in Western Europe, which may be of greater significance in stratigraphic correlation than previously thought.  相似文献   

18.
Tao Deng 《Geobios》2008,41(6):719
Ningxiatherium euryrhinus sp. nov. is a relatively large elasmothere rhino from the Linxia Basin in northwestern China found in the early Bahean, which corresponds to the early Vallesian (MN 9), ca. 11.1 Ma. It is much larger than the extant Ceratotherium simum and has a single horn. Ningxiatherium is similar to the late Miocene Parelasmotherium from Gansu and Shanxi, but differs in having partially ossified nasal septum, terminal nasal horn boss, shallower nasal notch above the P3/P4 boundary, and much shorter premolars. N. euryrhinus sp. nov. differs from N. longirhinus from the late Miocene of Zhongning, Ningxia in northwestern China by its larger size, relatively wider nasals, shallower nasal notch, and sub-quadrangular occlusal surface of M3. In the Linxia Basin, the other early late Miocene (Bahean or Vallesian) elasmotheres are known from complete skulls or isolated teeth. They include two genera and three species: Parelasmotherium linxiaense, P. simplum, and Iranotherium morgani. They lack a nasal septum, but Ningxiatherium has one. The age of N. euryrhinus is early late Miocene based on direct association with biochronologic indicator taxa, such as Dinocrocuta gigantea, Hipparion dongxiangense, and Chilotherium primigenius. N. euryrhinus is more primitive than N. longirhinus sp. nov. in having a sub-quadrangular M3, a shallower nasal notch, and the presence of DP1 in adults.  相似文献   

19.
Paramecium novaurelia Beale and Schneller, 1954, was first found in Scotland and is known to occur mainly in Europe, where it is the most common species of the P. aurelia complex. In recent years, two non-European localities have been described: Turkey and the United States of America. This article presents the analysis of intraspecific variability among 25 strains of P. novaurelia with the application of ribosomal and mitochondrial loci (ITS1-5.8S-ITS2, 5′ large subunit rDNA (5′LSU rDNA) and cytochrome c oxidase subunit 1 (COI) mtDNA). The mean distance observed for all of the studied P. novaurelia sequence pairs was p = 0.008/0.016/0.092 (ITS1-5.8S-ITS2/5′LSU rDNA/COI). Phylogenetic trees (NJ/MP/BI) based on a comparison of all of the analysed sequences show that the studied strains of P. novaurelia form a distinct clade, separate from the P. caudatum outgroup, and are divided into two clusters (A and B) and two branches (C and D). The occurrence of substantial genetic differentiation within P. novaurelia, confirmed by the analysed DNA fragments, indicates a rapid evolution of particular species within the Paramecium genus.  相似文献   

20.
Chiara Angelone  Lorenzo Rook 《Geobios》2011,44(2-3):151-156
Alilepus meini nov. sp., a new leporid known only from the Early Messinian of central-western Italy (Baccinello-Cinigiano basin, V3 faunal assemblage; Tuscany), is described here. A. meini nov. sp. is an endemic taxon – not inherited from the older Tusco-Sardinian assemblages – of the continental and balanced BCB V3 fauna. The peculiarities of A. meini nov. sp. mainly reside in the occlusal surface of p3 (very large anteroconid, extremely short talonid, deep and crenulated posterior flexids, extremely thin protoisthmus) and P3 (wide hypoflexus). A. meini nov. sp. seems closely related to Alilepus turolensis, as testified by shared morphological characters (globous anteroconid and deep protoflexid, very thin protoisthmus). Palaeobiogeographical evidences support morphological data as A. meini nov. sp. and A. turolensis are the only two species of the genus present in western Europe.  相似文献   

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