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having a global distribution in places now occupyingboth lower and higher latitudes. The genusHiemalora, which appeared to be endemic to theRussian block, also has wide biogeographic coverage.These fossils assign an Ediacaran (550–543 Ma) age for the host Lakheri Limestone andsuggest that the Lakheri unit was depositedwithin 6 million years of the Precambrian–Cambrian boundary. They also support and refinethe traditional view of the Late Neoproterozoicage for the lower Bhander Group. Thesefossils provide positive stratigraphic clues forlocating the Precambiran–Cambrian boundarystrata in the overlying Lakheri–Sirbu segment ofthe Vindhyan sequence. They also indicate adepositional environment typical of a muddyshallow shelf setting above storm wave-base.2008040403新 旧 未 定 门 类 = Problematica old and new. ( 英文 ). Jenner R A; Littlewood D T J. PhilosophicalTransactions of the Royal Society B: BiologicalSciences, 2008, 363(1496): 1503-1512Problematica are taxa that defy robust phylogeneticplacement. Traditionally the term wasrestricted to fossil forms, but it is clear that extanttaxa may be just as difficult to place,whether using morphological or molecular (nucleotide,gene or genomic) markers for phylogenyreconstruction. We discuss the kinds andcauses of Problematica within the Metazoa, aswell as criteria for their recognition and possiblesolutions. The inclusive set of Problematicachanges depending upon the nature and qualityof (homologous) data available, the methods ofphylogeny reconstruction and the sister taxa inferredby their placement or displacement. Weaddress Problematica in the context of precladisticphylogenetics, numerical morphologicalcladistics and molecular phylogenetics, andfocus on general biological and methodologicalimplications of Problematica, rather than presentinga review of individual taxa. Rather thanexcluding Problematica from phylogeny reconstruction,as has often been preferred, we concludethat the study of Problematica is crucialfor both the resolution of metazoan phylogenyand the proper inference of body plan evolution.2008040404伊 朗 东 北 部 Kopet–Dagh 地 区 Alborz 山 脉 晚奥 陶 世 末 期 - 早 志 留 世 的 胞 石 化 石 : 生 物 地层 和 古 生 物 地 理 = Latest Ordovician–earlySilurian chitinozoans from the eastern AlborzMountain Range, Kopet–Dagh region, northeasternIran: biostratigraphy and palaeobiogeography.( 英 文 ). Ghavidel-syooki M; VecoliM. Review of Palaeobotany and Palynology,2007, 145(1-2): 173-192Chitinozoans were extracted from latest Ordovicianto early Silurian strata in the AlborzMountain Range, northeastern Iran; 24 specieswere identified and six local biozones established.Five new chitinozoan species are described:Ancyrochitina bojnourdensis, Ancyrochitinafatemae, Ancyrochitina longifilosa, Angochitinairanica, and Angochitina multipodspina.Correlation with existing formal biozonationssuggests that the uppermost part of theGhelli Formation is of mid-Ashgill age and thatMember I of the Niur Formation ranges fromearly Rhuddanian to late Telychian. The recoveredchitinozoan fauna is dominated by specieswhich are endemic to the study area. A significantproportion of taxa is shared with typicalBaltican assemblages, suggesting palaeobiogeographicalaffinities between Iran and the Balticapalaeocontinent. Taxa shared with typicalNorth Gondwanan assemblages are only a minorcomponent of the Iranian chitinozoan fauna. Thepresent results confirm previous observationsthat current appreciation of chitinozoan provincialismmay be affected by sample-and (palaeo)geographiccoverage biases, particularly forthe Silurian. Similarly, the application of existingbiostratigraphic schemes for the dating of theIranian Silurian sediments proved problematical,confirming the need of incorporating more datafrom little known areas (such as Iran) in globaldatabases.2008040405加 拿 大 纽 芬 兰 Bonavista 半 岛 埃 迪 卡 拉 生 物群 = Ediacaran biota on Bonavista Peninsula,Newfoundland, Canada. ( 英 文 ). Hofmann H J;O'brien S J; King A F. Journal of Paleontology,2008, 82(1): 1-36 15 图 版 .Newly found fossils in the Conception and St.John's groups of the Bonavista Peninsula considerablyextend the known geographic distributionof the Ediacaran fossils in Newfoundland. Theyoccur in deepwater sediments and are preservedas epireliefs, forming census populations underneathvolcanic ash layers throughout a more than1 km thick turbiditic sequence. The exposed fossiliferousunits comprise the Mistaken Point,Trepassey, Fermeuse, and Renews Head formations.The remains are tectonically deformed,with long axes of elliptical discs aligned parallelto cleavage strike; shortening of originally circularbedding surface features is on the order of30–50% (averaging 35%). The assemblage includesAspidella, Blackbrookia, Bradgatia,Charnia, Charniodiscus, Fractofusus, Hiemalora,and Ivesheadia. These occur throughoutthe succession, with Aspidella being the mostcommon genus, followed by Charnia andCharniodiscus. Four new taxa are described,with candelabra-like fossils with a Hiemalora-125