首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Fossil Elaeocarpus species with spherical fruits are redescribed and compared with extant species. Information on the distribution of E. mackayi (F. Muell.) Kirchheimer and E. spackmaniorum Rozefelds is provided. Additional notes on the morphology of E. spackmaniorum Rozefelds are also included; and collections from Guildford, in Victoria, are considered conspecific. Elaeocarpus occultus sp. nov. is described from the Haddon deep leads in Victoria; it has a spherical inner mesocarp, bastionate ornamentation, foraminae in the mesocarp wall and mesosutural ridges, which represent a combination of characters unique within extant Australian Elaeocarpus species. The fossil fruit record of Elaeocarpus is systematically significant because it demonstrates that the genus was morphologically diverse by the Miocene in Australia. Biogeographically, the genus also had a different, or more widespread distribution in Australia during the Cenozoic.  相似文献   

2.
Gard, H.J.L. & Fordyce, R.E., August 2016. A fossil sea turtle (Testudines: Pan-Cheloniidae) from the upper Oligocene Pomahaka Formation, New Zealand. Alcheringa 41, XX–XX. ISSN 0311-5518.

An isolated turtle xiphiplastron similar to that of Puppigerus sp. is described from the upper Oligocene (27.3–25.2 Ma) Pomahaka Formation near Tapanui, Otago, New Zealand. The bone is unlike any previously described turtle from the Cenozoic of New Zealand and is from a newly recognized estuarine vertebrate locality. It represents the first Oligocene cheloniid turtle bone described from the southwest Pacific.

Henry J. L. Gard [] and R. Ewan Fordyce, [], Department of Geology, University of Otago, PO Box 56, Dunedin, 9054, Otago, New Zealand.  相似文献   


3.
Computed tomography (CT) and traditional techniques were used to study the internal morphology of modern fruits of Pleiogynium timoriense (DC.) Leenh., and phosphatized and silicified fruits that were considered to belong to the genus. The results demonstrate that phosphatized fruits from the Oligocene–Miocene Dunsinane site at Riversleigh and silicified fruits from the Oligocene Glencoe Site, which are both in Queensland, are referable to Pleiogynium. The Riversleigh material (Pleiogynium wannanii Rozefelds, Dettmann & Clifford sp. nov.) is very similar to extant P. timoriense (DC.) Leenh. Both possess locules that, in the vertical axial plane, are asymmetrically reniform and enclosed by a two-layered endocarp, the inner layer woody and resistant to decay, the outer of fibres and parenchyma, surrounded by a mesocarp of fibres and sclereids and a parenchymatous exocarp. The outer mesocarp is sculpted by meridionally arranged, elongate depressions (germination apertures) situated at the dorsal surface of each locule; erosion of the mesocarp and outer endocarp provides passage for emergence of the embryo’s radicle on germination. The silicified material from Glencoe (P. parvum Rozefelds, Dettmann & Clifford sp. nov.) is smaller in all its parts and has locules that are ovate in the vertical axial plane. Discrete, cap-like, opercula are not evident in the fruit wall of the fossil and extant fruits studied. The presence of Pleiogynium, and associated taxa, indicates the existence of rainforest communities at Glencoe, and mixed open forest/rainforest at Riversleigh during Oligocene–Miocene times. The multilocular, fossil fruit described as Pleiogynium mitchellii Collinson, Manchester and Wilde from the Eocene deposits at Messel Quarry, Germany, is not considered to belong in the genus, as evidence of elongate depressions on the dorsal surface of the fruit stones has not been demonstrated conclusively, and its internal morphology/anatomy differs significantly from that of Pleiogynium.  相似文献   

4.
?erňanský, A. & Hutchinson, M.N., 2012. A new large fossil species of Tiliqua (Squamata; Scincidae) from the Pliocene of the Wellington Caves (New South Wales, Australia). Alcheringa, 1–6. ISSN 0311-5518.

We describe an isolated frontal bone referable to a new species, Tiliqua laticephala (Scincidae), from the Pliocene Big Sink doline of the Wellington Caves, central eastern New South Wales, Australia. The bone is very robust, is unusually broad and thick, especially around the bases of the subolfactory processes and represents a large and heavily built lizard. The fossil has multiple fragmentary osteoderms in the frontal region, showing asymmetry in shape and thickness that do not correspond to the more regularly arranged anterior head shields of other scincoids. The specimen shares two unusual character states with extant Tiliqua, especially the large armoured species, T. rugosa. Other large skinks related to T. rugosa (other Tiliqua spp., Corucia zebrata, Egernia cunninghamii, Bellatorias major, Liopholis kintorei) are less similar in terms of frontal shape, thickness, sculpture, osteoderm ornamentation, and positioning of adjacent bones.  相似文献   

5.
Hampe, O., Witzmann, F. & Asbach, P., 2014. A benign bone-forming tumour (osteoma) on the skull of a fossil balaenopterid whale from the Pliocene of Chile. Alcheringa 38, xxx–xxx. ISSN 0311–5518.

A pathology of the fossil baleen whale ‘Megapterahubachi from the early Pliocene of Chile is described. It is a bony outgrowth on the left side of the supraoccipital, which is interpreted as a benign bone-forming tumour (osteoma). This diagnosis is based on X-ray imaging and CT scans of the abnormal bone, revealing a homogeneously dense internal structure with no evidence for lytic areas. The osteoma described here in ‘Megaptera’ hubachi is the first unequivocal evidence of a bone tumour in a cetacean, fossil or extant.

Oliver Hampe [] and Florian Witzmann [], Museum für Naturkunde, Leibniz-Institut für Evolutions- und Biodiversitätsforschung, Invalidenstraße 43, D-10115 Berlin, Germany; Patrick Asbach [], Institut für Radiologie, Charité—Universitätsmedizin Berlin, Charitéplatz 1, D-10117 Berlin, Germany. Received 28.8.2013, revised 7.11.2013, accepted 12.11.2013.  相似文献   

6.
A new macropodine genus and species, Silvaroo bila, is described from the Pliocene Chinchilla Sand of Queensland. The generic concept of Protemnodon is reviewed, and it is concluded that two Pliocene species previously placed in that genus (bandharr and buloloensis) belong in Silvaroo. Species of Silvaroo resemble the modern forest wallabies of Papua New Guinea (species of Dorcopsis and Dorcopsulus) and also bear close phenetic resemblance to the late Miocene Dorcopsoides fossilis. Forest wallabies are not known from mainland Australia after the middle Pliocene, but occur in the late Pliocene and Pleistocene of New Guinea.  相似文献   

7.
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   

8.
Marsola, J.C.A., Grellet-Tinner, G., Montefeltro, F.C., Sayão, J.M., Hsiou, A.S. & Langer, M.C., 2014. The first fossil avian egg from Brazil. Alcheringa 38, 563–567. ISSN 0311-5518.

In contrast to the rich record of eggs from non-avian dinosaurs, complete eggs attributable to Mesozoic birds are relatively scarce. Nevertheless, several well-preserved specimens have been discovered over the last three decades revealing functional and phylogenetic characters that shed light on the breeding strategies of extinct birds. Here we report the first fossil avian egg from Brazil, which was discovered in Upper Cretaceous strata of São Paulo in the southeastern part of the country. The taxonomic identity and structural features of the biomineralized tissues were determined using a combination of Scanning Electron Microscopy, Wave Dispersion Energy analyses and Computed Tomography. These show that the 125.5-μm-thick shell of the 31.4?×?19.5?mm egg incorporates three structural layers of similar thickness with both prismatic and aprismatic boundaries. Close similarity between the Brazilian bird egg and those of enantiornithines from the Upper Cretaceous Bajo de la Carpa Formation (Río Colorado Subgroup) of Argentina advocates affinity with basal Ornithothoraces. Furthermore, coherency of their depositional contexts might imply a compatible preference for breeding and nesting environments.

Júlio Cesar de A. Marsola [], Annie Schmaltz Hsiou [] and Max C. Langer [], Laboratório de Paleontologia de Ribeirão Preto, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Avenida Bandeirantes 3900, Ribeirão Preto, São Paulo state, 14040-901, Brazil. Gerald Grellet-Tinner [], Centro Regional de Investigaciones La Rioja—Consejo Nacional de Investigaciones Científicas y Técnicas, Entre Ríos y Mendoza s/n, 5301 Anillaco, Argentina; Orcas Island Museum, PO Box 134, 181 North Beach Road, Eastsound, WA 98245. Felipe C. Montefeltro [], Departamento de Zoologia, Universidade Estadual Paulista, Avenida 24A 1515, Rio Claro, São Paulo State, 13506-900, Brazil. Juliana M. Sayão [], Laboratório de Diversidade do Nordeste, Núcleo de Biologia, Centro Acadêmico de Vitória, Universidade Federal de Pernambuco, Rua do Alto do Reservatório s/n, Bela Vista, Vitória de Santo Antão, Pernambuco state, 52050-480, Brazil. Received 18.12.2013; revised 30.4.2014; accepted 18.5.2014.  相似文献   

9.
Khan, M.A., Babar, M.A., Akhtar, M., Iliopoulos, G., Rakha, A. & Noor, T., November 2015. Gazella (Bovidae, Ruminantia) remains from the Siwalik Group of Pakistan. Alcheringa 40, xxx–xxx. ISSN 0311-5518.

New gazelle fossils are described from the Siwalik Group of Pakistan. The material includes horncores, maxilla and mandible fragments, and isolated teeth. The available samples are assigned to three Gazella species: Gazella sp. in the Lower Siwalik Subgroup (ca 14.2–11.2 Ma), and G. lydekkeri and G. superba in the Middle Siwalik Subgroup (ca 10.2–3.4 Ma). Based on a review of the Siwalik Group gazelles, G. padriensis is synonymized with G. lydekkeri. Gazella superba Pilgrim, 1939 sensu stricto is a large form and is a valid species of the genus in the Siwalik Group.

Muhammad Akbar Khan [], Muhammad Adeeb Babar [], Muhammad Akhtar [], Allah Rakha [], Tuba Noor [], Abu Bakr Fossil Display & Research Centre, Department of Zoology, Quid-e-Azam Campus, Punjab University (54590), Lahore, Pakistan; George Iliopoulos [], Geology Department of the University of Patras, Patras, Greece.  相似文献   


10.
MENZIES, J., DAVIES, H.L., DUNLAP, W.J. & GOLDING, S.D., June, 2008. A possible early age for a diprotodon (Marsupialia: Diprotodontidae) fossil from the Papua New Guinea highlands. Alcheringa 32, 129–147. ISSN 0311-5518.

A fossil diprotodon jawbone coated and impregnated with a well-cemented fine breccia or tuff was recovered from weakly consolidated Pleistocene lacustrine sediments near Yonki in the Papua New Guinea highlands. The fine breccia includes angular rock and mineral fragments derived from country rock, accretionary lapilli and clay minerals. It does not include any identifiable primary volcanic material. The presence of accretionary lapilli and lack of volcanic clasts suggests an origin by phreatic eruption—an explosive eruption driven by the violent escape of gas. Minerals in the fine breccia have an age of 13.2 ± 0.2 Ma, middle Miocene, as indicated by 40Ar/39Ar analysis. This is the age of the country rock that was blasted by the phreatic eruption. Igneous activity in the Yonki area is thought to have ceased at 7.4 Ma (younger age limit of Elandora Porphyry; late Miocene), and so it is likely, but not certain, that the phreatic eruption occurred not later than 7.4 Ma. The jawbone, as far as can be told from its poor condition, is dentally similar to the late Pliocene and possibly Pleistocene ‘Kolopsiswatutense recovered from other sites in New Guinea. Probably, the jawbone, or the living marsupial, was buried in the fine breccia at the time of the phreatic eruption, and its remains were subsequently reworked by river erosion and redeposited in the lacustrine sediments. Recrystallization and loss of primary texture in some of the bone may be a result of heating at the time of, or preceding, the eruption.  相似文献   

11.
Kaulfuss, U., Harris, A.C., Conran J.G. & Lee, D.E., 2014. An early Miocene ant (subfam. Amblyoponinae) from Foulden Maar: the first fossil Hymenoptera from New Zealand. Alcheringa 38, 568–574. ISSN 0311-5518.

The ant subfamily Amblyoponinae is presently represented in New Zealand by one endemic species in the cosmopolitan genus Stigmatomma and an introduced Australian species of Amblyopone. The fossil record of the group is restricted to two species of Stigmatomma from late Eocene Baltic Amber. Here, we describe the third fossil record, an Amblyopone-like specimen from the early Miocene of Otago, southern New Zealand, based on a winged male that resembles the extant A. australis Erichson in size, general habitus and characters of wing venation, but also shares features with the African amblyoponine genus Zymmer. This represents the first fossil record of Amblyoponinae from the Southern Hemisphere and the first example of Hymenoptera among the few pre-Quaternary insect fossils known from New Zealand. It suggests a long history of Amblyoponinae in New Zealand and Australia.

Uwe Kaulfuss [] and Daphne E. Lee [], Department of Geology, University of Otago, PO Box 56, Dunedin 9016, New Zealand; Anthony C. Harris [], Otago Museum, PO Box 6202, Dunedin 9059, New Zealand; John G. Conran [], ACEBB & SGC, School of Earth and Environmental Sciences, The University of Adelaide, Benham Bldg, DX 650 312, Adelaide SA 5005, Australia. Received 18.3.2014; revised 15.5.2014; accepted 23.5.2014.  相似文献   

12.
Campanile rupicolum sp. nov. is described from the early Miocene Upper Maude Limestone Member of Maude, Victoria. The genus has not hitherto been recorded from Victoria, a part of the Southeast Australian biogeographic Province, and was thought to be characteristic of the Austral-Indopacific Province. This is the oldest occurrence of the genus so far recorded from Australia.  相似文献   

13.
Earp, C., 29 January 2019. Costulatotheca schleigeri (Hyolitha: Orthothecida) from the Walhalla Group (Early Devonian) at Mount Pleasant, central Victoria, Australia. Alcheringa. Alcheringa 43, 220–227. ISSN 0311-5518

A number of hyolith fragments (including one operculum), found in Early Devonian marine turbidites at Mt Pleasant, near Alexandra, central Victoria, are described as Costulatotheca schleigeri gen. et sp. nov., the first confirmed record of the order Orthothecida in the Devonian of Australia. Index fossils found at this locality (Uncinatograptus sp. cf. U. thomasi and Nowakia sp. ex gr. N. acuaria) indicate an age of Pragian or earliest Emsian. The taphonomy of rare rafted shelly fossils indicates that flysch deposition occurred in a very-low-energy environment into which there were occasional bursts of high-energy turbidites carrying allochthonous fossils from shallower water.

Clement Earp [], 1 De Havilland Place, Onerahi, Whangarei 0110, New Zealand.  相似文献   


14.
Sphenophytes are a common floral element in the Triassic of Gondwana. Most sphenophyte compression fossils have been conventionally assigned to a few, presumably very widespread species of Neocalamites based on vegetative features of the stems (or pith casts) and the foliage. During recent decades, however, new reports on morphological and anatomical details of some of these fossils have cast doubt on the systematic affinities of many Gondwanan Triassic sphenophytes. Here we describe Neocalamites suberosus (Artabe & Zamuner) nov. comb. et emend. and Schizoneura africana Feistmantel emend. from several Triassic deposits in the central Transantarctic Mountains and Victoria Land, East Antarctica. The material enables a critical reevaluation of morphological and anatomical features that have been historically used to define the two genera, including leaf-base morphology, degree of leaf fusion, stem vasculature and vallecular canals, and features of the nodal diaphragm. The diagnoses of Neocalamites and Schizoneura are emended so that they more accurately reflect recent advances in our understanding of the anatomy and ontogeny of these plants.

[Benjamin Bomfleur [bbomfleur@ku]edu], Rudolph Serbet [serbet@ku.edu], Edith L. Taylor [etaylor@ku.edu] and Thomas N. Taylor [tntaylor@ku.edu], Department of Ecology and Evolutionary Biology, and Biodiversity Institute, University of Kansas, Lawrence, KS 66045, USA; Ignacio H. Escapa [iescapa@mef.org.ar], CONICET—Museo Paleontológico Egidio Feruglio, Trelew, Chubut 9100, Argentina. Received 4.7.2012; revised 22.12.2012; accepted 7.1.2013.

Bomfleur, B., Escapa, I.H., Serbet, R., Taylor, E.L. & Taylor, T.N., 2013. A reappraisal of Neocalamites and Schizoneura (fossil Equisetales) based on material from the Triassic of East Antarctica. Alcheringa 37, 1–17. ISSN 0311-5518.  相似文献   

15.
Yates, A.M., December, 2008. Two new cowries (Gastropoda: Cypraeidae) from the middle Miocene of South Australia. Alcheringa 32, 353–364. ISSN 0311-5518.

The South Australian specimens of the cypraeids Umbilia leptorhyncha (McCoy, 1877) and Lyncina (Austrocypraea) contusa (McCoy, 1877) are re-examined. Umbilia caepa sp. nov. differs from U. leptorhyncha in its smaller size, more strongly pyriform shape, weaker and less extensive apertural dentition, plate-like columellar margin of the posterior canal and more extensive basal flanges. True U. leptorhyncha is also recorded from the Cadell Formation of South Australia, demonstrating that the two species were sympatric in the Murray Basin. The specimens originally referred to Cypraea contusa var. from the Cadell Formation have had a confusing taxonomic history and they are here named as a new species Lyncina (Austrocypraea) cadella sp. nov. The new species differs from true L. (A.) contusa in its smaller size, less extensive malleations of the dorsal surface, fewer apertural teeth and a projecting internal margin of the fossula. These two new species boost a small but growing list of species that were endemic to the Murray Basin during the middle Miocene.  相似文献   

16.
Pisera, A. & Bitner, M.A., December, 2007. The sponge genus Brachiaster (Pachastrellidae, Demospongiae) and its first known fossil representative, from the late Eocene of southwestern Australia. Alcheringa 31, 365‐373. ISSN 0311-5518.

The pachastrellid genus Brachiaster Wilson (Pachastrellidae, Demospongiae, Porifera) has had until now no known fossil representatives. Here we describe its first known fossil representative from the late Eocene of southwestern Western Australia, assigned to Brachiaster claudelevii sp. nov. Brachiaster claudelevii has well-developed axial canals in the mesotriders, which points to it being intermediate in character between the typical tetraxial desmas of lithistids, and tetraxial spicules of non-lithistid demosponges. This further supports the position of Brachiaster among the Pachastrellidae. The geographic and bathymetric distribution of the extant and newly described fossil representatives of Brachiaster indicates that the Eocene sponge described here is important in understanding the evolution of Indo-West Pacific sponges because it points to a long evolutionary history and complex biogeographic distribution of this lineage of pachastrellid sponges.

Andrzej Pisera [apis@twarda.pan.pl], Maria Aleksandra Bitner [bitner@twarda.pan.pl], Institute of Paleobiology, Polish Academy of Sciences, ul. Twarda 51/55, 00‐818 Warszawa, Poland; received 24.3.2006; revised 14.6.2006.  相似文献   

17.
Agnolin, F.L., July 2016. Unexpected diversity of ratites (Aves, Palaeognathae) in the early Cenozoic of South America: palaeobiogeographical implications. Alcheringa 41, xxx–xxx. ISSN 0311-5518.

Ratitae is represented in South America exclusively by Rheidae. Recently, the oldest purported fossil rheid, Diogenornis fragilis, was attributed by several authors to various other ratite clades. A new revision of museum fossil specimens from Argentina has resulted in the discovery of several ratite specimens that clearly do not belong to Rheidae, but resemble other clades. The newly identified specimens derive from Paleogene and Miocene strata. The great diversity of non-rheid Patagonian ratites ended via extinction of several groups by the late Miocene, probably owing to enhanced aridity that also favoured the dispersal of arid-adapted rheids. The new specimens described here reinforce the hypothesis that the traditional vicariant biogeographical model, which proposes ratite clades originated exclusively before the breakup of the Gondwana supercontinent, is questionable owing to the unexpected diversity of various ratite clades in South America, and also in Europe and Africa. This might indicate that the history of Ratitae was more complex than previously envisioned.

Federico L. Agnolin* [], Laboratorio de Anatomía Comparada y Evolución de los Vertebrados, Museo Argentino de Ciencias Naturales ‘Bernardino Rivadavia’, Av. Ángel Gallardo, 470 (1405), Buenos Aires, Argentina. *Also affiliated with: Fundación de Historia Natural ‘Félix de Azara’, Departamento de Ciencias Naturales y Antropología, Universidad Maimónides, Hidalgo 775 (C1405BDB) Ciudad Autónoma de Buenos Aires, República Argentina.  相似文献   


18.
Chen, J., Beattie, R., Wang, B., Jiang, H., Zheng, Y. & Zhang, H., 12 April 2019. The first palaeontinid from the Late Jurassic of Australia (Hemiptera, Cicadomorpha, Palaeontinidae). Alcheringa 43, 449–454. ISSN 0311-5518.

Palaeontinidae, an extinct group of large arboreal insects, has the most diverse record among the Mesozoic Hemiptera, but only a few taxa have been reported from the Southern Hemisphere. Herein, Talbragarocossus jurassicus Chen, Beattie & Wang gen. et sp. nov., one of the earliest representatives of ‘late’ Palaeontinidae, is described and illustrated from the Upper Jurassic Talbragar Fossil Fish Bed in New South Wales, Australia. This new taxon constitutes the first representative of Palaeontinidae in Australia and the first Jurassic example in Gondwanaland, providing significant distributional and stratigraphic extensions to the family.

Jun Chen*? [] and Yan Zheng? [], Institute of Geology and Paleontology, Linyi University, Shuangling Road, Linyi 276000, China. Bo Wang? [], Hui Jiang [] and Haichun Zhang [] State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, 39 East Beijing Road, Nanjing 210008, China. Robert Beattie [], Australian Museum, 1 William St., Sydney, NSW 2010, Australia. ?Also affiliated with: State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, 39 East Beijing Road, Nanjing 210008, China. ?Also affiliated with: Shandong Provincial Key Laboratory of Depositional Mineralization & Sedimentary Minerals, Shandong University of Science and Technology, Qingdao, Shandong 266590, China.  相似文献   

19.
LI, Y.J., HAN, G., NEL, A. REN, D., PANG, H. & LIU. X.L., September 2012. A new fossil petalurid dragonfly (Odonata: Petaluroidea: Aktassiidae) from the Cretaceous of China. Alcheringa 36, 321–324. ISSN 0311-5518.

The new petalurid species Pseudocymatophlebia boda is described from Lower Cretaceous strata of Inner Mongolia, China. It provides additional morphological characters for this genus, which has been previously recorded from the Lower Cretaceous of England. Together with Aktassia, it is the second aktassiid genus with a very wide distribution, even though this family remains known only from Eurasia. Furthermore, a new name, Brachaktassia gen. nov., is proposed to replace the brachiopod genus Aktassia Popov, 1976.  相似文献   

20.
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   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号