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1.
Wang, Z.H., Bergström, S.M., Zhen, Y.Y., Chen, X. & Zhang, Y.D., 2013. On the integration of Ordovician conodont and graptolite biostratigraphy: New examples from Gansu and Inner Mongolia in China. Alcheringa 37, 510–528. ISSN 0311-5518.

Few Ordovician successions in the world contain both biostratigraphically highly diagnostic conodonts and graptolites permitting an integration between standard biozones based on these fossil groups. The Sandbian Guanzhuang section in the vicinity of Pingliang in the Gansu Province has an outstanding graptolite record through most of the Nemagraptus gracilis and Climacograptus bicornis graptolite biozones. Calcareous interbeds in the succession yield biostratigraphically important conodonts, including some species used for biozonations in Baltoscandia and the North American Midcontinent. Likewise, the middle–upper Darriwilian Dashimen section in the Wuhai region of Inner Mongolia hosts both diverse graptolites of the Pterograptus elegans, Didymograptus murchisoni and lowermost Nemagraptus gracilis biozones, and conodonts of Midcontinent and Baltoscandic types. The distribution patterns of these index fossil groups provide an unusual opportunity to closely correlate conodont and graptolite biozones in the middle to upper Darriwilian to Sandbian interval. For instance, the base of the C. bicornis Biozone is approximately coeval with the base of the Baltoscandic B. gerdae Subbiozone and a level near the middle of the North American P. aculeata Biozone.

Zhi-hao Wang [zhwang@nigpas.ac.cn] Xu Chen [xu1936@gmail.com], and Yuan-dong Zhang [ydzhang@nigpas.ac.cn], Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China; Stig M. Bergström [stig@geology.ohio-state.edu], School of Earth Sciences, Division of Earth History, The Ohio State University, Columbus, OH 43210, USA; Yong Yi Zhen [yongyi.zhen@austmus.gov.au], Australian Museum, 6 College Street, Sydney NSW 2010, Australia.  相似文献   

2.
Muir, L.A., Zhang, Y.-D. & Lin, J.-P. 2012. New material from the Ordovician of China indicates that Inocaulis is a graptolite. Alcheringa 37, 558–559. ISSN 0311-5518.

The problematic Early Palaeozoic fossil Inocaulis has been regarded as an alga, a graptolite and a hydroid by different authors. A new specimen from the Ordovician (late Darriwilian) of Guizhou Province (China) shows fusellar banding, confirming that it is a benthic graptolite.

Lucy A Muir [lucy@asoldasthehills.org], Yuan-dong Zhang [ydzhang@nigpas.ac.cn], Jih-Pai Lin [jplin@nigpas.ac.cn] (corresponding author), State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, No. 39 East Beijing Road, Nanjing 210008, PR China. Received 13.12.2012; revised 10.5.2013; accepted 13.5.2013.  相似文献   

3.
Benson, R.B.J., Fitzgerald, E.M.G., Rich, T.H. & Vickers-Rich, P., 2013. Large freshwater plesiosaurian from the Cretaceous (Aptian) of Australia. Alcheringa 37, 1–6. ISSN 0311-5518

We report a large plesiosaurian tooth from the freshwater early–middle Aptian (Early Cretaceous) Eumeralla Formation of Victoria, Australia. This, combined with records of smaller plesiosaurian teeth with an alternative morphology, provides evidence for a multitaxic freshwater plesiosaurian assemblage. Dental and body size differences suggest ecological partitioning of sympatric freshwater plesiosaurians analogous to that in modern freshwater odontocete cetaceans. The evolutionarily plastic body plan of Plesiosauria may have facilitated niche differentiation and helped them to exclude ichthyosaurs from freshwater environments during the Mesozoic. However, confirmation of this hypothesis requires the discovery of more complete remains.

Roger B.J. Benson [roger.benson@earth.ox.ac.uk], Department of Earth Sciences, University of Oxford, South Parks Road, Oxford OX1 3AN, UK; Erich M.G. Fitzgerald [efitzgerald@museum.vic.gov.au], Thomas H. Rich [trich@museum.vic.gov.au], Museum Victoria, GPO Box 666, Melbourne, Victoria 3001, Australia; Thomas H. Rich and Patricia Vickers-Rich [pat.rich@monash.edu], School of Geosciences, Monash University, Clayton, Victoria 3800, Australia. Received 30.10.2012; revised 27.1.2013; accepted 31.1.2013.  相似文献   

4.
Muir, L.A. & Botting, J.P., December, 2007. Graptolite faunas and monaxonid demosponges of the Cyrtograptus lundgreni event (late Wenlock, Silurian) interval from the Orange district, New South Wales. Alcheringa 31, 375-395. ISSN 0311-5518.

Three monograptid and five retiolitid graptoloids, and one species of sponge, are described from late Wenlock sections (Cyr. lundgreni and Co. ludensis biozones) at Spring Creek and Wallace Creek, near Orange, New South Wales, Australia. The sponge Janussenia orangense gen. et sp. nov. is the first monaxonid demosponge to be described from the Australian Silurian. An object containing broken Testograptus testis, and interpreted as the faecal pellet of a predator or scavenger on graptoloids, is described.

Lucy A. Muir [l.muir@nhm.ac.uk], Department of Palaeontology, Natural History Museum, Cromwell Road, London SW7 5BD, UK. Joseph P. Botting [joe@asoldasthehills.org], 2C Roslyn Close, Mitcham CR4 3BB, UK. Received 28.4.2006; Revised 10.10.2006.  相似文献   

5.
Dettmann, M.E., Clifford, H.T., Peters, M., June 2012. Emwadea microcarpa gen. et sp. nov.—anatomically preserved araucarian seed cones from the Winton Formation (late Albian), western Queensland, Australia. Alcheringa, 217–237. ISSN 0311-5518.

A new genus and species, Emwadea microcarpa Dettmann, Clifford & Peters, is established for ovulate/seed cones with helically arranged cone scales bearing a centrally positioned, inverted ovule from the basal Winton Formation (late Albian), Eromanga Basin, Queensland. The cones are small, prolate ellipsoidal (9.5–14 mm vertical axis, 6.3–8.7 mm transverse axis) with wedge-shaped cone scales bearing winged seeds attached adaxially to the scale only by tissues surrounding the vasculature entering the ovule. Ovuliferous tissue that is free from the cone scale extends distally from the chalaza; the seeds' lateral wings are derived from the integument. Foliage attached to the cones is spirally arranged, imbricate and with spreading and incurved bifacial blades with acute tips; stomata are arranged in longitudinal files and are confined to the adaxial surface. The cone organization testifies to placement within the Araucariaceae, and is morphologically more similar to Wollemia and Agathis than to Araucaria.

Mary Dettmann [mary.dettmann@qm.qld.gov.au] and Trevor Clifford, Queensland Museum, PO Box 3300, South Brisbane, Q 4101, Australia; Mark Peters, PO Box 366 Gumeracha, SA 5233, Australia. Received 31.3.2011; revised 23.8.2011; accepted 5.9.2011.

  相似文献   

6.
Beattie, R.G. & Nel, A., June 2012. A new dragonfly, Austroprotolindenia jurassica (Odonata: Anisoptera), from the Upper Jurassic of Australia. Alcheringa, 189–193. ISSN 0311-5518.

Austroprotolindenia jurassica gen. et sp. nov., a new Mesozoic Australian dragonfly, is described from the Talbragar Fossil Fish Bed (Upper Jurassic) of eastern Australia. It shows some similarities with the Eurasian Mesozoic petalurid family Protolindeniidae, but its incomplete state of preservation prevents us assigning it to a particular anisopteran clade.

Robert G. Beattie [rgbeattie@bigpond.com] PO Box 320, Berry 2535, NSW, Australia. André Nel [anel@mnhn.fr] CNRS UMR 7205, CP 50, Entomologie, Muséum National d'Histoire Naturelle, 45 rue Buffon, F-75005 Paris, France. Received 6.4.2011; revised 8.6.2011; accepted 15.6.2011.  相似文献   

7.
Wyse Jackson, P.N., Reid, C.M. & McKinney, F.K., iFirst article, 2011. Fixation of the type species of the genus Protoretepora de Koninck, 1878 (Bryozoa, Fenestrata). Alcheringa, 1–2. ISSN 0311-5518.

The type species of the Palaeozoic bryozoan genus Protoretepora de Koninck, 1878 was originally fixed as Fenestella ampla Lonsdale in Darwin, 1844, but this taxon has been shown to belong to the bryozoan genus Parapolypora Morozova & Lisitsyn, 1996 Morozova, I. P. and Lisitsyn, D. V. 1996. Revision of the genus Polypora. Paleontologicheskii Zhurnal, 1996(4): 3847. [English translation: Paleontological Journal30(5), 530–541] [Google Scholar]. The original type species designation for Protoretepora de Koninck, 1878 is set aside, and in accordance with Article 70.3 of the International Code of Zoological Nomenclature (4th edition, 1999) the nominal species Protoretepora crockfordae Wyse Jackson, Reid & McKinney, 2011 from the Permian of Tasmania, Australia is herein fixed as the type species.  相似文献   

8.
Shi, Guang R., 1994:03:28. The Late Palaeozoic brachiopod genus Jakutoproductus Kashirtsev 1959 and the Jakutoproductus verchoyanicus Zone, northern Yukon Territory, Canada. Alcheringa 18, 103–120. ISBN 0311-5518.

The familial and subfamilial position, species composition, and geographic distribution of the Late Palaeozoic productid genus Jakutoproductus Kashirtsev 1959 are reviewed. Jakutoproductus is placed in the subfamily Plicatiferinae Muir-Wood & Cooper 1960 of the family Plicatiferidae. Eighteen described species from the Russian Arctic. Mongolia, northeast China, and northern Yukon Territory, Canada are assigned to Jakutoproductus. The Jakutoproductus verchoyanicus Zone of late Sakmarian to Artinskian age, most likely early Artinskian (Aktastinian), here established is based on material from the Jungle Creek Formation, northern Yukon Territory, Canada, and is correlated with the following horizons in Russia: the Osennin Horizon in the Verchoyan Mountains, the lower Munugudjak Horizon of the Kolyma-Omolon Massif, the Hipkhoshin Suite of east Zabaikal, the lower Bhang Horizon of Taimyr, and an unnamed sandstone-shale unit on the north island of Novaya Zemlya.  相似文献   

9.
Brea, M., Zamuner, A.B., Matheos, S.D., Iglesias, A. & Zucol, A.F., December, 2008. Fossil wood of the Mimosoideae from the early Paleocene of Patagonia, Argentina. Alcheringa 32, 427–441. ISSN 0311-5518.

An anatomically preserved mature stem from the Salamanca Formation (early Paleocene) at Palacio de Los Loros, central Patagonia, Argentina, is described and assigned to Paracacioxylon frenguellii sp. nov. The material was preserved by siliceous permineralization and shows features of the secondary xylem typical of subfamily Mimosoideae. This species represents the oldest record of the genus and of the Leguminosae along the western border of Gondwana, and is the world's second oldest record of Leguminosae wood. The species is characterized by ring-porous to semi-ring-porous vessels that are solitary, in multiples of 2–4 and clustered, simple perforation plates, alternate and vestured inter-vessel pitting, homocellular 1–6 seriate rays, tyloses, crystals and diffuse apotracheal, vasicentric paratracheal and confluent axial parenchyma. Paracacioxylon frenguellii has anatomical similarities to Acacia Miller. The presence of Paracacioxylon frenguellii associated with pulvinate leaves suggests that the legumes might have been a component of mesothermal forests developed along the western margin of the Golfo San Jorge Basin during the early Paleocene.  相似文献   

10.
Ni Yunan & Cooper, R. A., 1994:03:28. The graptolite Glossograptus Emmons and its proximal structure. Alcheringa 18, 161–167. ISSN 0311-5518.

New specimens of Glossograptus acanthus from the Ningkuo Shale of China, preserved in relief, help to resolve the much debated problem of the structure of Glossograptus. A model for the proximal structure of the genus is proposed, based on the new material and on Finney's (1978) Athens Shale specimens. The model confirms that Glossograptus has homologous structure and development with Pseudisograptus, and isograptid development type is primitive for the group containing both genera. A cladogram is presented in which the suborder Glossograptina Jaanusson (with families Glossograptidae and Cryptograptidae) together with family Corynoididae Bulman are subsumed within a redefined family Glossograptidae.  相似文献   

11.
12.
Abstract

Paul Kennedy. The Parliament of Man: The Past, Present, and Future of the United Nations. Toronto, ON: HarperCollins, 2006. Pp. xvii, 361. $36.95 (CDN); Ronald St John Macdonald and Douglas M. Johnston, eds. Towards World Constitutionalism: Issues in the Legal Ordering of the World Community. Leiden: Brill, 2005. Pp. xviii, 968. €235.00; $317.00 (US); S. Neil MacFarlane and Yuen Foong Khong. Human Security and the UN: A Critical History. Bloomington and Indianapolis, IN: Indiana University Press, 2006. Pp. xix, 346. $35.00 (US), paper; David M. Malone. The International Struggle over Iraq: Politics in the UN Security Council, 1980–2005. New York, NY: Oxford University Press, 2006. Pp. xiv, 398. $59.95 (CDN); Michael J. Matheson. Council Unbound: The Growth of UN Decision Making on Conflict and Postconflict Issues after the Gold War. Washington, DC: United States Institute of Peace Press, 2006. Pp. xvi, 422. $19.95 (US), paper; Ramesh Thakur. The United Nations, Peace, and Security: From Collective Security to the Responsibility to Protect. New York, NY: Cambridge University Press, 2006. Pp. xvi, 388. $32.99 (US), paper.  相似文献   

13.
Rich, T.H., Hopson, J.A., Gill, P.G., Trusler, P., Rogers-Davidson, S., Morton, S., Cifelli, R.L., Pickering, D., Kool, L., Siu, K., Burgmann, F.A., Senden, T., Evans, A.R., Wagstaff, B.E., Seegets-Villiers, D., Corfe, I.J., Flannery, T.F., Walker, K., Musser, A.M., Archer, M., Pian, R. & Vickers-Rich, P., June 2016. The mandible and dentition of the Early Cretaceous monotreme Teinolophos trusleri. Alcheringa 40, xx–xx. ISSN 0311-5518.

The monotreme Teinolophos trusleri Rich, Vickers-Rich, Constantine, Flannery, Kool & van Klaveren, 1999 Rich, T.H., Vickers-Rich, P., Constantine, A., Flannery, T.F., Kool, L. & van Klaveren, N., 1999. Early Cretaceous mammals from Flat Rocks, Victoria, Australia. Records of the Queen Victoria Museum and Art Gallery 106, 134. [Google Scholar] from the Early Cretaceous of Australia is redescribed and reinterpreted here in light of additional specimens of that species and compared with the exquisitely preserved Early Cretaceous mammals from Liaoning Province, China. Together, this material indicates that although T. trusleri lacked a rod of postdentary bones contacting the dentary, as occurs in non-mammalian cynodonts and basal mammaliaforms, it did not share the condition present in all living mammals, including monotremes, of having the three auditory ossicles, which directly connect the tympanic membrane to the fenestra ovalis, being freely suspended within the middle ear cavity. Rather, T. trusleri appears to have had an intermediate condition, present in some Early Cretaceous mammals from Liaoning, in which the postdentary bones cum ear ossicles retained a connection to a persisting Meckel’s cartilage although not to the dentary. Teinolophos thus indicates that the condition of freely suspended auditory ossicles was acquired independently in monotremes and therian mammals. Much of the anterior region of the lower jaw of Teinolophos is now known, along with an isolated upper ultimate premolar. The previously unknown anterior region of the jaw is elongated and delicate as in extant monotremes, but differs in having at least seven antemolar teeth, which are separated by distinct diastemata. The dental formula of the lower jaw of Teinolophos trusleri as now known is i2 c1 p4 m5. Both the deep lower jaw and the long-rooted upper premolar indicate that Teinolophos, unlike undoubted ornithorhynchids (including the extinct Obdurodon), lacked a bill.

Thomas H. Rich [], Sally Rogers-Davidson [], David Pickering [], Timothy F. Flannery [], Ken Walker [], Museum Victoria, PO Box 666, Melbourne, Victoria 3001, Australia; James A. Hopson [], Department of Organismal Biology & Anatomy, University of Chicago,1025 East 57th Street, Chicago, IL 60637, USA; Pamela G. Gill [], School of Earth Sciences, University of Bristol, Bristol BS8 1RJ, U.K. and Earth Science Department, The Natural History Museum, Cromwell Road, London SW7 5BD, UK; Peter Trusler [], Lesley Kool [], Doris Seegets-Villiers [], Patricia Vickers-Rich [], School of Earth, Atmosphere and Environment, Monash University, Victoria 3800, Australia; Steve Morton [], Karen Siu [], School of Physics and Astronomy, Monash University, Victoria 3800, Australia; Richard L. Cifelli [] Sam Noble Oklahoma Museum of Natural History, University of Oklahoma, Norman, OK 73072, USA; Flame A. Burgmann [], Monash Centre for Electron Microscopy, 10 Innovation Walk, Monash University, Clayton, Victoria 3800, Australia; Tim Senden [], Department of Applied Mathematics, Research School of Physical Sciences and Engineering, The Australian National University, Canberra, Australian Capital Territory 0200, Australia; Alistair R. Evans [], School of Biological Sciences, Monash University, Victoria 3800, Australia; Barbara E. Wagstaff [], School of Earth Sciences, The University of Melbourne, Victoria 3010, Australia; Ian J. Corfe [], Institute of Biotechnology, Viikinkaari 9, 00014, University of Helsinki, Finland; Anne M. Musser [], Australian Museum, 1 College Street, Sydney NSW 2010 Australia; Michael Archer [], School of Biological, Earth, and Environmental Sciences, University of New South Wales, Sydney, NSW 2052, Australia; Rebecca Pian [], Division of Paleontology, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024-5192, USA. Received 7.4.2016; accepted 14.4.2016.  相似文献   

14.
Aye Ko Aung, Ng Tham Fatt, Kyaw Kyaw Nyein & Myo Htut Zin, 2013. New Late Permian rugose corals from Pahang, peninsular Malaysia. Alcheringa 37, 422–434. ISSN 0311-5518.

Late Permian rugose corals are described from a limestone unit of the Gua Musang Formation at Selborne Estate, Padang Tengku area, Pahang, peninsular Malaysia. These include one genus, Iranophyllum, which is reported for the first time from Malaysia, with two new species Iranophyllum aequabilis and I. pahangense belonging to Waagenophyllidae. A Late Permian age is confirmed by a Paleofusulina–Colaniella–Reichelina foraminiferal fauna co-preserved with the corals.

Aye Ko Aung [akaung.mm@gmail.com], Ng Tham Fatt [thamfatt@gmail.com], Kyaw Kyaw Nyein [konyein@gmail.com], Department of Geology, University of Malaya, 50603, Kuala Lumpur, Malaysia and Myo Htut Zin [myohtutgreat@googlemail.com], Lab. Services, Pte. Co. Ltd., Singapore. Received 16.10.2012; revised 5.1.2013; accepted 17.1.2012.  相似文献   

15.
Qianyu Li & Brian Mcgowran, 1994:03:28. Evolutionary morphological changes in the new genus Duoforisa: implication for classification and habit of the unilocular Foraminifera. Alcheringa 18, 121–134. ISSN 0311-5518.

Unlike other unilocular foraminifera, the new genus Duoforisa from the Late Oligocene to Early Miocene possesses a kidney-shaped test with two apertures on its distal ends. It contains two distinct and successional species, both new, and differentiated by their apertural details. In Duoforisa rima the apertures are slit-like, and become radial in the descendant D. diducta. Intermediate forms have transitional apertural configurations between the slit type and radial type, accompanied also by a change of the test outline from subtriangular to compactly U-shaped. The evolution of the lineage occurred during a period of enhanced upwelling in the Early Miocene and it was terminated just before the global warming at the Early-Middle Miocene boundary. This example suggests evolution of the unilocular foraminifera through successional morphological changes in test shape and in the aperture. Unilocular taxa have tended to flourish or speciate in cool or upwelling environments. Their contraction in the latest Early Miocene to early Middle Miocene was probably due to global warming and well oxygenated conditions which were widespread in the neritic domains of southern Australia.  相似文献   

16.
Nel, A., Frese, M., McLean, G. & Beattie R., May 2017. A forewing of the Jurassic dragonfly Austroprotolindenia jurassica from the Talbragar Fish Bed, New South Wales, Australia. Alcheringa 41, 532–535. ISSN 0311-5518.

The discovery of a well-preserved dragonfly forewing in the Upper Jurassic Talbragar Fish Bed near Gulgong and attributed to Austroprotolindenia jurassica Beattie & Nel allows this taxon to be placed in Protolindeniidae. It extends the palaeogeographical distribution of this family, previously known only from the Jurassic of Europe, to Australia.

André Nel [], CNRS UMR 7205, CP 50, Entomologie, Muséum National d’Histoire Naturelle, 45 rue Buffon, F-75005, Paris, France; Michael Frese [], University of Canberra, Institute for Applied Ecology and Faculty of Education, Science, Technology and Mathematics, Bruce, ACT 2601, Australia; Graham McLean [], The Australian Museum, 1 William St., Sydney, NSW 2010, Australia; Robert Beattie [], The Australian Museum, 1 William St., Sydney, NSW 2010, Australia.  相似文献   


17.
Wainman, C.C., Hannaford, C., Mantle, D. & McCabe, P.J., April.2018. Utilizing U–Pb CA-TIMS dating to calibrate the Middle to Late Jurassic spore-pollen zonation of the Surat Basin, Australia to the geological time-scale. Alcheringa XX, xx-xx.

Spore-pollen palynostratigraphy is commonly used to subdivide and correlate Jurassic continental successions in eastern Australia and thus aid the construction of geological models for the petroleum and coal industries. However, the current spore-pollen framework has only been tenuously calibrated to the geological time-scale. Age determinations are reliant on indirect correlations of ammonite and dinoflagellate assemblages from New Zealand, the North West Shelf of Australia and Southeast Asia to the standard European stages. New uranium-lead chemical abrasion thermal ionization mass spectrometry (U–Pb CA-TIMS) dates from 19 tuff beds in the Middle–Upper Jurassic Injune Creek Group of the Surat Basin enables regional spore-pollen palynostratigraphic zones to be precisely dated for the first time. These results show the base of the APJ4.2 and APJ4.3 subzones are similar in age to previous estimates (Middle Jurassic, Bathonian) from indirect palynostratigraphic correlation. However, the base of the APJ5 Zone and the APJ6.1 Subzone may be somewhat younger than previously estimated, possibly by as much as 2.5 and 4.2 Myrs, respectively. The continued utilization of U–Pb CA-TIMS dates will further refine the absolute ages of these zones, improve the inter- and intra-basinal correlation of Middle–Upper Jurassic strata in eastern Australian basins and greatly enhance intercontinental correlations.

Carmine Christopher Wainman [] and Peter James McCabe [] Australian School of Petroleum, University of Adelaide, SA, 5005, Australia; Carey Hannaford [] and Daniel Mantle [] MGPalaeo Pty Ltd, 5 Arvida Street, Malaga, WA, 6090, WA, Australia.  相似文献   

18.
Zhuravlev, A. Yu., & Gravestock, D. I., 1994:03:28. Archaeayaths from Yorke Peninsula, South Australia and archaeocyathan Early Cambrian zonation. Alcheringa 18, 1–54. ISSN 0311-5518.

Two assemblages of archaeocyaths are documented from Lower Cambrian outcrops and drillholes on Yorke Peninsula. South Australia. The older assemblage (11 species) occurs in the uppermost Kulpara Formation and conformably overlying basal Parara Limestone, and is equivalent to Lower Faunal Assemblage II in the Flinders Ranges. The younger assemblage (28 species plus Acanthhcyathus and Rodiocyathus) occurs in the Koolywurtie Member near the top of the Parara Limestone. Equivalent taxa are widespread in the Flinders Ranges, western New South Wales and Antarctica. Archaeocyathan distribution is now sufficiently well known to propose three assemblage zones and two informal assemblages for regional correlation. No new taxa have been added, but Erugatocyathus scutatus (Hill) and Pycnoidocyathus latiloculatus (Hill), hitherto known only from Antarctica, are found in the upper assemblage on Yorke Peninsula. Irregular archaeocyathan systematics are discussed, the ontogeny of Archaeopharetra irregularis (Tylor) clarified, and Kruseicnema Debrenne. Gravestock & Zhuravlev, represented by K. gracilis (Gordon), is fully described.  相似文献   

19.
Wang Yi, Fu Qiang, Xu Honghe, & Hao Shougang, June, 2007. A new Late Silurian plant with complex branching from Xinjiang, China. Alcheringa 31, 111-120. ISSN 0311-5518.

A new fossil plant is described from the middle part of the Wutubulake Formation (late Pridoli) of Xinjiang, China. This plant demonstrates at least two orders of branching. The first-order axis has pseudomonopodial branching with alternately attached second-order axes. Fertile units are alternately inserted along the second-order axis, and consist of a branching system and two sporangia at each tip. Sporangia are narrowly obovate with rounded apex and tapering base. This plant is characterized by more complex branching than other Silurian and Early Devonian plants, and is named Wutubulaka multidichotoma gen. et sp. nov., and placed under open higher-order nomenclature.  相似文献   

20.
VandenBerg, Alfons H.M., November 2017. Fragmentation as a novel propagation strategy in an Early Ordovician graptolite. Alcheringa 42, 1–9. ISSN 0311-5518.

Catenagraptus communalis gen. nov. sp. nov. is a late Floian (Early Ordovician) graptolite from Victoria, Australia, only found as fragments, with each fragment resembling an assemblage of uniserial tubarium-like structures (pseudotubaria) connected by threads (aulons). Individual pseudotubaria consist of a fallosicula and a stipe, both of which are linked by aulons to other pseudotubaria. Adjacent pseudotubaria are in a parent–offspring relationship. Aulons can be generated from both the proximal and distal extremities of fallosiculae, and from the ends of stipes. The aulons are interpreted to have been grown by the zooid that occupied either the fallosicula or the terminal theca of the stipe. Aulons were pathways for a zooid that built a fallosicula at the end of the aulon. This process was repeated to form the assemblage. None of the assemblages contain a true sicula, which suggests that the assemblages present evidence of a new, asexual propagation strategy that involved fragmentation and dispersal. As this interpretation is radical, other models explored are partial sclerotization and modified sicular spines.

Alfons H.M. VandenBerg [], Museum Victoria, GPO Box 666, Melbourne 3001, Victoria, Australia.  相似文献   


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