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1.
Abstract: The OcruranusEohalobia group, whose members were variously considered to be brachiopods, bivalves, chitons, tommotiids and coeloscleritophorans, are difficult to classify because of lack of morphological detail and evidence for skeletal reconstruction. New specimens from South China reveal more information about OcruranusEohalobia and allow progress towards deciphering the skeletal reconstruction and phylogenetic affinity of this enigmatic group. Many specimens have a phosphatic inner and outer coat (mould) with empty space in between that resulted from dissolution of the original shell. Moreover, many of the internal moulds show a previously unknown type of shell microstructure that consisted of stacked layers of highly organized, acicular crystallites that radiated from the apex of the shell towards the aperture. The dissolved shell and needle‐like crystals suggest an original calcareous, probably aragonitic, shell mineralogy. A few specimens also show a polygonal texture in regions that suggests the shell had a thin, prismatic inner shell microstructure. Ocruranus and Eohalobia belong to the same skeleton, and we herein synonymize Eohalobia with the older Ocruranus. Moreover, new specimens from Meishucun reveal a third type of shell plate, similar in form and inferred placement to intermediate valves of chitons. Ocruranus is likely a mollusc, and possibly a member of the chiton stem lineage. If so, then the beginning of the known record of chitons would be extended back from late Cambrian (Saukia Zone; Furongian) to early Cambrian (Meishucunian; Series 1).  相似文献   

2.
Mobergellans are disc-shaped problematic fossils of phosphatic composition bearing prominent muscle attachment structures on the presumed internal surface. They are found exclusively in sediments of Early Cambrian age, mainly from Laurentia, Baltica and Siberia. Type material ofDiscinella brastadi Poulsen, 1932 from North-East Greenland is re-studied and synonomised withDiscinella micans (Billings, 1871). Specimens from Siberia described asD. brastadi are re-assigned toMobergella hexactina n. sp., and specimens from Siberia described asMobergella radiolata Bengtson, 1968 are re-assigned toM. sibirica n. sp.Aktugaia triangula Mis-Sarzhevsky, 1976 from Kazakhstan is redescribed, and its relationship to other mobergellans is discussed.   相似文献   

3.
4.
浙西早寒武世梅树村期棒状化石   总被引:2,自引:0,他引:2  
该文记述了浙江省西部江山县新塘坞地区灯影组(梅树村期)中新发现的矿化骨骼化石——浙江棒(新属)Zhejiangorhabdion gen.nov.。该化石的形态与以往化石类群均不相同,为个体微小的棒状,表面具较复杂的纹饰,不同个体间的纹饰都有一定变化,推测是动物体内不同部位的骨棒所具有的特征,代表了一个新的化石类群。新属的发现丰富了梅树村期动物群的内容,对了解具骨骼动物群体在这一时期的演化具有一定的意义。  相似文献   

5.
Pleistocene erratic boulders in northern Germany and Denmark yield upper Lower Cambrian ellipsocephaloid trilobites described asEpichalnipsus anartanus n. gen., n. sp. andBerabichia erratica n. sp. They are supposedly derived from an unidentified late Early Cambrian unit from central Sweden and most probably come from an otherwise poorly fossiliferous stratigraphie interval of theHolmia kjerulfi Zone. Although both species are new, their systematic affinities permit a refined intercontinental correlation between Baltica and western Gondwana. An erratum to this article is available at .  相似文献   

6.
ABSTRACT

A new fossil species of the genus Scutus (Scutus mirus n. sp.) is described from five Late Oligocene to Early Miocene (Waitakian to Altonian; 25.2–15.9?Ma) localities in the South Island, New Zealand. It is one of the oldest fossil species of Scutus known and probably inhabited very shallow, sub-tropical waters surrounding Zealandia during this time. The holotype of Scutus petrafixus Finlay, 1930 is re-examined; it is possibly from All Day Bay, Kakanui (Waitakian 25.2–21.7?Ma). The New Zealand species documented herein significantly expand our understanding of the fossil record of this shallow-marine molluscan lineage, and by proxy, also indicate the presence of very shallow coastal marine environments around the late Oligocene and early Miocene in southern Zealandia.  相似文献   

7.
A new glypheid lobster (Crustacea, Glypheidae), Glyphea pisuergae sp. nov. is described from the Early Jurassic (late Pliensbachian–early Toarcian) of Salinas de Pisuerga, Palencia, Spain. This species represents the second record for the genus in the Early Jurassic.  相似文献   

8.
The Meishucunian Stage of south China provides a window on the radiation of skeleton-bearing metazoans at the beginning of the Cambrian. The section at Meishucun has been proposed as a candidate for a global stratotype of the Precambrian-Cambrian boundary. Fossils and Strata No. 24, by Qian Yi & Stefan Bengtson, presents a thorough reinvestigation of the bizarre Meishucunian biota on the basis of exquisitely preserved material. This monograph will become a central reference on the earliest Cambrian faunas and the problem of the Precambrian-Cambrian boundary. Qian Yi & Stefan Bengtson: Palaeontology and biostratigraphy of the early Cambrian Meishucunian Stage in Yunnan Province, south China Abstract: The skeletal fossils of the early Cambrian Meishucunian Stage from two key localities (Meishucun, Jinning County, and Xianfeng, Xundian County) in eastern Yunnan Province, China, are described and illustrated in detail to provide a basis for improved palaeobiological and biostratigraphical work. About 1250 new SEM illustrations (including a large number of stereo-pairs) of well preserved material are presented. The taxonomy is extensively revised. When biological and preservational variability are taken into account, the number of genera and species may be reduced through synonymy to about one third of that reported in the literature. Thirty-eight genera (2 of which are new) and 57 species (5 of which are new) are described. The biology and affinities of many of these taxa are also discussed, but excursions into supra-generic taxonomy are generally restrained. The Meishucunian biotas of Yunnan consist of three successive assemblages with very few taxa in common. The first, the Anabarites-Protohertzina-Arthrochites Assemblage, is dominated by Anabarites and other sedentary tube-dwelling organisms, but non-sedentary benthic mollusc-like fossils (Canopoconus) and probable predators (Protohertzina) also occur. The key elements of this fauna have a wide geographical distribution and may be compared with the earliest skeletal faunas on the Siberian Platform, the Canadian Cordillera, and other regions. The second, the Siphogonuchites-Paragloborilus Assemblage, is characterized by a great diversity of vagile mollusc-like and multisclerite-bearing animals, but also sedentary tube-dwellers and some possible predators (Cyrtochites and Yunnan-odus) occur. This fauna is largely endemic. The third. the Lapworthella-Tannuolina-Sinosachites Assemblage, is mainly characterized by widely distributed taxa of multisclerite-bearing animals (chancelloriids, Halkieria, Tannuolina, and Lap worthella). It has elements in common with late Atdabanian faunas in other regions of the world.  相似文献   

9.
Summary Geological, papaeontological and microfacies studies in the Lower Cambrian carbonate complex of the G?rlitz Synclinorium (eastern Germany/Saxony/Lusatian region) provide new data for the fossil content, depositional history and palaeogeography. The Lower Cambrian of the G?rlitz Synclinorium belongs to the facies zones 5, 7 and 8 ofWilson (1975)-platform rim with connections to the open ocean and to the restricted platform areas. An extraordinarily rich fauna was found with elements which are in some cases new for Europe (Rhombocorniculum cancellatum Cobbold,Fordilla sibirica Krasilova, Calodiscus lobatus Hall,Archaeooides granulatus Qian,Archiasterella pentactina Sdzuy,Allonia sp.,Obliquatheca aldanica Sysoiev,Conotheca circumflexa Missarzhevsky,Microcornus elongatus Missarzhevsky,Lenalituus sp.,Pelagiella cf.lorenzi Kobayashi,Beshtashella sp.,Comluella sp.,Cambroclavithidae gen. et sp. indet., Helcionellidae gen. et sp., indet. Eocrinoidea gen. et sp. indet.) This fauna indicates Lower Cambrian (higher Atdabanian/Botomian) age and reveals palaeobiogeographical connections to the Siberian Platform, to the Mediterranean area and to China. A somewhat new stratigraphical subdivision of the Lower Cambrian sequence (Zwetau Formation) is described. New units are established within the Ludwigsdorf Member (the carbonatic lower part of the sequence), the ‘Lower Ludwigsdorf Member’ (massive dolostone) and the ‘Upper Ludwigsdorf Member’ (bedeed limestones and their equivalents). The subsequentLusatiops Member is subdivided intoSerrodiscus Bed (claystones) andLusatiops Bed (siltstones).  相似文献   

10.
Summary P. symploci Pat. is a new record to India andP. dalbergiae Niessl. a new addition to the Fungi of Bombay. Association of spermogonia with the developing ascocarps has been noted in three out of the seven species described in this paper, confirming the earlier observations ofTilak (1959) of the occurrence of spermatization as a common process of sexuality in this genus.  相似文献   

11.
The succession of early species of the genus Kepplerites is established in the Upper Bathonian-Lower Callovian beds of Central Russia and compared with the ammonoid succession of East Greenland and Western Europe. Late Bathonian members of the genus Kepplerites from the Middle Volga Region are generally similar, though not identical to those from Greenland, whereas the Early Callovian Kepplerites species and their immediate Bathonian ancestors are represented by species common to all three regions. The analysis of the ammonoid distribution suggests a connection between the East Greenland and Central Russian marine basins in the Early and Middle Bathonian and in the Early Callovian, and their short-term isolation in the Late Bathonian. A new species, Kepplerites (Kepplerites) aigii sp. nov., is described from the Upper Bathonian (keuppi Zone) of the Alatyr River basin (Middle Volga Region).  相似文献   

12.
EARLY CAMBRIAN BRACHIOPODS FROM NORTH-EAST GREENLAND   总被引:3,自引:0,他引:3  
Abstract:  A diverse assemblage of late Early Cambrian brachiopods is described from the Bastion and Ella Island formations of North-East Greenland. The fauna includes nine species, representing all three extant brachiopod subphyla in addition to the stem group brachiopod Mickwitzia cf. occidens . Four linguliforms: Eoobolus priscus , Botsfordia caelata , Micromitra bella , Vandalotreta sp., three rynchonelliforms: Obolella crassa , Kutorgina reticulata , and an unidentified chileid plus a possible craniiform species occur. The fauna shows similarities to late Early Cambrian (Dyeran Stage) brachiopod faunas of eastern Canada and the United States, but also to faunas from the late Early Cambrian (Botomian–Toyonian equivalent) of Australia, Antarctica and Siberia.  相似文献   

13.
Abstract

The two recently collected mammalian dentary fragments from the Eocene Youganwo Formation of Guangdong Province, southern China, are referred to the anthracotheriid species Anthracokeryx naduongensis based on phylogenetic analysis and size comparison. One of these specimens (SYSU-M-1) is the first mammal fossil described from the Youganwo Formation. It was attributed previously to the perissodactyl genus Lunania. Anthracokeryx naduongensis was described originally from the lower upper Eocene Na Duong Formation in Northern Vietnam. The second record of this species supports a basal upper Eocene correlation for the Youganwo Formation, which was estimated previously as middle or late Eocene.  相似文献   

14.
记述中国水虻亚科1新记录属:诺斯水虻属Nothomyia Loew,1869及2新种:即长茎诺斯水虻N. elongoverpa sp. nov.和云南诺斯水虻N. yunnanensis sp.nov.模式标本保存在贵州大学昆虫研究所标本馆。  相似文献   

15.
Botting, J.P., Muir, L.A., Xiao, S., Li, X. & Lin, J.‐P. 2012: Evidence for spicule homology in calcareous and siliceous sponges: biminerallic spicules in Lenica sp. from the Early Cambrian of South China. Lethaia, Vol. 45, pp. 463–475. The relationships of the extant sponge classes, and the nature of the last common ancestor of all sponges, are currently unclear. Early sponges preserved in the fossil record differ greatly from extant taxa, and therefore information from the fossil record is critical for testing hypotheses of sponge phylogenetic relationships that are based on modern taxa. New specimens of the enigmatic sponge Lenica sp., from the Early Cambrian Hetang Biota of South China, exhibit an unusual spicule structure. Each spicule consists of a siliceous core with an axial canal, an organic outer layer and a middle layer interpreted to have been originally calcium carbonate. This finding confirms previous work suggesting the existence of biminerallic spicules in early sponges. Combined with data from other early sponges, the new findings imply that the two fundamental spicule structures of modern sponges were derived from a compound, biminerallic precursor. Spicules are therefore homologous structures in Calcarea and Silicea, and if sponges are paraphyletic with respect to Eumetazoa, then spicules may also have been a primitive feature of Metazoa. □Calcarea, Early Cambrian, Hetang Biota, phylogeny, Silicea, taphonomy.  相似文献   

16.
Ten specimens of two phosphatic fossils have been recently discovered in lower and middle portions of Middle Cambrian Jince Formation in the Czech Republic. They are attributed to the genus Sphenothallus Hall, 1847 and described as two separate species; comparatively small conchs are described as S. kozaki sp. nov., the much larger specimens characterized by its smooth and partly flexible organo-phosphatic walls of shell are determined as ?S. kordulei sp. nov. Sphenothallus is known to range from Cambrian to Permian and accommodates numerous species. However, its Cambrian distribution is considerably restricted. Generally rare specimens have been described from Lower to Middle Cambrian of Laurentia and from the Lower Cambrian of Gondwana and peri-Gondwana. The new record of Sphenothallus from the Jince Biota represents a notable extension of their geographic range.  相似文献   

17.
Summary The present paper describes eight Foliicolous Fungi imperfecti from Jabalpur (India). These include four new species viz.Ramularia alangii Hasija onAlangium lamarckii, Colletotrichum holopteleae Hasija onHoloptelea integrifolia, Gloeosporium wendlandiae Hasija onWendlandia exserta andPhyllosticta macropycnidiai Hasija onSolanum melongena. Discosia artocreas Tode exFr. onTerminalia sp. is a new fungus record for the country raising the total number ofDiscosia from India to five.Heteropogon contortus forCurvularia lunata (Wakker)Boed. andBarleria priniotes forCercospora barlericola Payak &Thirum. are new hosts record from India, andCercospora tridacis-procumbentis Govindu &Thirum. onTridax procumbens is a new record for the state.  相似文献   

18.
19.
The bradoriid genusHipponicharion Matthew, 1886 is one of the oldest known Cambrian ostracods. Until now, five species have been documented and another three taxa have been tentatively assigned to one or another species.Hipponicharion has been recorded from Poland, Germany, Morocco as well as from Canada and Great Britain.Hipponicharion hispanicum n. sp. represents the first Cambrian ostracod documented from Spain.Hipponicharion taidaltensis n. sp., formerlyH. aff.geyeri Hinz-Schallreuter, 1993 andH. elickii n. sp., formerlyH. cf.eos sensuElicki, 1994 have also been restudied in this paper.Hipponicharion seems to be restricted to the Acadobaltic Province sensuSdzuy (1972). The systematic relationships of the Bradoriida, which is controverse, is briefly outlined, emphasizing close affinities to the Ostracoda.   相似文献   

20.
Summary The namePseudoeurotium globosum Rai andTewari n. sp. has been given to a fungus isolated from soil collected from the banks of a stream in village Harchandpur, District Rae Bareli, (U.P.) India. This form is distinguished from any other described so far in this genus, in having multisporous asci with large globose ascospores. P.globosum n. sp. inhabits a specialised habitat, and this along with the fact that it was isolated only byWarcup's Soil-plate Method, makes it an ecologically interesting form.  相似文献   

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