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A new species Paraconularia abagaensis n. sp. is established, based on newly discovered conulariid fossils collected in Abaga Banner, Inner Mongolia, China. The periderm of the new species is characterized by equal faces, 12–26 transverse ribs per cm with nodes numbering from 4–6 per mm, adapertural spines in the interspaces, alternated ribs along the midline, and apical angle ranging approximately from 14° to 18°. The most similar species, P. salinensis, differs from P. abagaensis n. sp. in having a periderm with a significantly larger apical angle and a lower density of nodes. Co-occurring fossils (i.e., brachiopods, gastropods, bivalves, and plants) and U–Pb dates obtained in situ from detrital zircons suggest that the analyzed conulariid-bearing strata are Permian in age. Our study suggests that species previously established merely based on internal mold specimens may need further examination. The diagnosis of Paraconularia was revised and in the genus we identified three morphotypes, based on which we suggest that species whose midlines present ridges or grooves, and whose transverse ribs do not abruptly bend adaperturally at the edges of the corner grooves, be excluded from the genus Paraconularia.

Shen, Y. & Wang, X.L., July 2016. Howchinia Cushman, 1927 (Foraminifera) from the Mississippian Bei’an Formation and its distribution in South China. Alcheringa 40, xxx–xxx. ISSN 0311-5518.Howchinia Cushman is a useful biostratigraphic marker for Mississippian rocks. In South China, Howchinia has been reported from four sections: the Bei’an, Baping, Naqing and Yashui sections; with high species diversity in the Bei’an section. Ten species from the Mississippian Bei’an Formation in the Bei’an section are described in this paper: Howchinia bradyana, H. beleutensis, H. gibba, H. plana, H. convexa, H. subconica, H. subplana, Howchinia sp. A, Howchinia sp. B. and Howchinia beianensis sp. nov. Howchinia ranges from late Visean to early Bashkirian in South China. Howchinia species inhabited both shallow-water and relatively deep-water environments.Yang Shen [shenybj@126.com] and Xun-Lian Wang [wxl@cugb.edu.cn], State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, 29 Xuey...

Du, W., Wang, X.L., Komiya, T., Zhao, R. & Wang, Y., April 2016. Dendroid multicellular thallophytes preserved in a Neoproterozoic black phosphorite in southern China. Alcheringa 40, xxx–xxx. ISSN 0311-5518.A new form of dendroid multicellular thallophyte is documented in the Ediacaran Doushantuo phosphorite at Weng’an, Guizhou Province, southern China. The dendroid thallophytes have variable forms, possibly owing to heteromorphic variation. Many lateral branches extend from the upper portions of the main axes; the lateral branches bear terminal vegetative vesicles, reproductive vesicles, monosporangium-like discoidal vesicles and urn-shaped pseudoparenchymatous structures. The vegetative vesicles give rise to clavate pseudoparenchymatous structures, characterized by differentiation of the thallus medulla/cortex, which might represent an early stage of thallus development. An oogamous conceptacle arising from one carpogonial vesicle forms a highly specialized goblet-shaped conceptacle. The discovery of th...

Sun, N., Elias, R.J., Choh, S.-J., Lee, D.-C., Wang, X.-L. & Lee, D.-J., February 2016. Morphometrics and palaeoecology of the coral Agetolites from the Xiazhen Formation (Upper Ordovician), Zhuzhai, South China. Alcheringa 40, xxx–xxx. ISSN 0311-5518.Agetolites is a peculiar cerioid coral possessing traits of both tabulates and rugosans. The presence of numerous mural pores has been considered by some workers to indicate a relation to tabulates, although an affinity to rugosans has also been proposed based mainly on well-developed septa that alternate in length. Agetolites is by far the most common colonial coral in the Upper Ordovician Xiazhen Formation at Zhuzhai, in the JCY (Jiangshan–Changshan–Yushan) triangle region of South China. It occurs in various lithofacies representing a wide range of depositional environments. Five species are recognized and verified by cluster analysis, discriminant analysis, descriptive statistics and bivariate plots: A. yushanensis Lin, 1960, A. raritabulatus Lin, 1960, ...

Sponges are widely viewed as the most primitive metazoans. Sponge gemmule-like structures have been recovered from the lower part of the Doushantuo Formation in the Yangtze Gorges area (South China), that were deposited between 635 and 580 Ma. Gemmosclere-like structures are embedded in the outer coat of the sponge structures. Electron probe microanalyses (EPMA) of the gemmoscleresindicate that they have siliceous composition. The naked subspheroidal sponge structures are composed of three layers, consistent with the preservation of a tri-layered theca embedded with the gemmosclere-like structures. The potential fossils of the Ediacaran sponge gemmules in the Doushantuo Formation may provide one of the earliest records of sponges.

The Carboniferous System of South China is famous for its well-developed rock sequence, variety of depositional types, and abundant fossils. Three established Global Boundary Stratotype Section and Point (GSSP) markers have been identified in several sections in South China. Of these sections, the Pengchong section is the GSSP for the base of the Visean Stage, whereas the Dapoushang and Naqing (Nashui) sections are excellent reference sections for the bases of the Tournaisian and Bashkirian stages, respectively. Other sections have good potential for the four unestablished GSSPs and the Devonian–Carboniferous boundary in South China. The Naqing (Nashui) section is a candidate for the GSSPs of four stages: the Serpukhovian, Moscovian, Kasimovian, and Gzhelian stages. The regional stages of China include the Tangbagouan, Jiusian, Shangsian, Dewuan, Luosuan, Huashibanian, Dalaun, and Xiaodushanian. The history, definitions, reference sections, sedimentary characteristics, biostratigraphy, and correlations of...

Sponge spicules were extracted from dolostone in the lower part of the Neoproterozoic Doushantuo Formation in the Yangtze Gorges area (South China), which has an age of ∼630 million years. The spicules appear to occur in at least two morphologies; monaxons and triaxons with rays in various planes. Energy dispersive spectrometer (EDS) analysis indicates that the spicules are siliceous. Furthermore, closely spaced occurrences of hexactinellid sponge spicules are observed in thin sections. This study represents the first discovery of siliceous sponges from the well known standard section of the Neoproterozoic in South China, and also confirms the stratigraphie extension of the most primitive multicellular animal before the Gaskiers glaciation.

Anisotropic information of pre-stack 3D azimuth P wave from seismic data is already one of the most efficient and economic methods from reservoir fracture examination, which requires a wide azimuth for seismic data gathering. By forward simulation of the geophysical characteristics in fractured reservoirs, the relationship between azimuth distribution areas of seismic data gathering and fracture direction is studied. Narrow azimuth for seismic data gathering is also somewhat effective to describe fracture distribution characteristics. In addition, significant seismic property difference (amplitude, damping and frequency) can be made in fractured reservoirs, thus, fracture can be effectively examined by the seismic information of different offsets. All the results in the paper get excellent practical application.

The Ediacaran fossil Eoandromeda octobrachiata had a high conical body with eight arms in helicospiral arrangement along the flanks. The arms carried transverse bands proposed to be homologous to ctenophore ctenes (comb plates). Eoandromeda is interpreted as an early stem-group ctenophore, characterized by the synapomorphies ctenes, comb rows, and octoradial symmetry but lacking crown-group synapomorphies such as tentacles, statoliths, polar fields, and biradial symmetry. It probably had a pelagic mode of life. The early appearance in the fossil record of octoradial ctenophores is most consistent with the Planulozoa hypothesis (Ctenophora is the sister group of Cnidaria + Bilateria) of metazoan phylogeny.