四川威远恐龙足迹一新属

<正>1985年,自贡恐龙博物馆的朱时达、高人彦、彭光照根据四川威远县荣胜乡沙坝村村民李元吉、李鸣章的报告和地矿部第二地质大队提供的资料,在威远县荣胜乡老鸦坡下侏罗统珍珠冲组下部黄色砂岩上发掘出6个连续恐龙足迹化石,并把这批标本运回自贡恐龙博物馆保存。     

四川威远恐龙足迹一新属

1985年,自贡恐龙博物馆的朱时达、高人彦、彭光照根据四川威远县荣胜乡沙坝村村民李元吉、李鸣章的报告和地矿部第二地质大队提供的资料,在威远县荣胜乡老鸦坡下侏罗统珍珠冲组下部黄色砂岩上发掘出6个连续恐龙足迹化石,并把这批标本运回自贡恐龙博物馆保存。     

产自中国云南下禄丰组(下侏罗统)的爬行动物不完美硕鳄的再研究(英文)

一般认为植龙类在三叠纪末期灭绝,但有研究显示它们可能在欧洲和亚洲延续到了侏罗纪最早期。来自亚洲的证据是产自中国云南下禄丰组(?赫唐阶-锡内穆阶)的不完美硕鳄(Pachysuchus imperfectus)。重新研究显示不完美硕鳄正型标本和植龙类存在许多不同点,它可能属于一个保存较差的、分类位置无法确定的蜥脚型类恐龙头骨。这一属种的归入标本也无法明确归入某一类群,因此亚洲没有可靠的晚于三叠纪的植龙类化石记录。欧洲的侏罗纪植龙类化石也存在着同样的问题。因而认为,植龙类的化石记录仅限于三叠纪晚期。     

PHRAGMOTEUTHIDA (CEPHALOPODA: COLEOIDEA) FROM THE LOWER JURASSIC OF DORSET, ENGLAND

Abstract:  Phragmoteuthida from the Lower Jurassic (Upper Sinemurian) of Dorset, England, are fully described for the first time. Two species are recognized and described: Phragmoteuthis montefiorei (J. Buckman) and P. huxleyi sp. nov. Phragmocones have an apical angle of between 20 and 30 degrees, and relatively few chambers compared with belemnoids. The conotheca is multi-layered. The siphuncle is thick-walled. The pro-ostracum is long and three-lobed as in the Triassic species. Arms are short and bear pairs of slightly curved hooks. Shell and siphuncle structure do not indicate a close relationship with other coleoids.     

重庆侏罗系杨氏璧山上龙(一淡水蛇颈龙)的再研究(英文)

侏罗纪的蛇颈龙类化石主要发现于欧洲 ,在世界的其他地区则比较少见。亚洲的蛇颈龙化石 ,尤其是侏罗纪的属种大多破碎而难以鉴别 (Sato,1 998)。到目前为止 ,Bishanopliosaurusyoungi(Dong,1 980 )和Yuzhoupliosauruschengjiangensis(Zhang,1 985)是亚洲地区最为完整的侏罗纪蛇颈龙类化石 ,并且化石产自对于蛇颈龙而言比较罕见的淡水沉积 ,因此这些材料对于了解该类群的系统发育、历史动物地理和古生态来说非常重要。本文重新详细描述了采自中国重庆自流井组东岳庙段的杨氏璧山上龙2 ) (董枝明 ,1 980 )。愈合情况不好的椎体和椎弓以及耻骨的边缘形态表明 ,杨氏璧山上龙的正型标本是一个幼年个体的头后骨架。我们的研究表明杨氏璧山上龙主要依分叉的荐肋为特征 ,而这一性状在初次发表时作为颈肋特征被描述。璧山上龙的其他特征包括侧扁的神经棘以及狭窄的乌喙骨和肱骨上有一个突。经过重新修理的标本显示 ,坐骨和耻骨相对的面呈沟槽状 ,这一现象表明它们之间的接触关系要较原来描述的情况复杂 ,是一种依靠软骨的连接 ,而非直接接触。本文对杨氏璧山上龙的腰带部分进行了重新复原。O’Keefe (2 0 0 1 )的支序分析支持将Plesiosauria二分为Plesiosauroidea和Pliosauroidea,后者包含两个科 :Pliosauridae和     

A MAMMALIAN LOWER JAW FROM THE JURASSIC OF LINGYUAN, LIAONING

<正> In 1976, a right mandible of a Mesozoic mammal was collected by Messrs. Cheng Zhengwu and Yue Zhao of Institute of Geology, the Chinese Academy of Geological Sciences, from the Middle Jurassic in Lingyuan County, Liaoning Province, Northeast China (fig. 1), When they were studying the Mesozoic stratigraphy of that area. This fossil site is most probably from the same locality as that of Yabeinosaurus tenuis reported by C.C. Young in 1958. Both fossils are derived from the same horizon.     

A LONG-SNOUTED DYROSAURID (CROCODYLIFORMES, MESOEUCROCODYLIA) FROM THE PALEOCENE OF MOROCCO: PHYLOGENETIC AND PALAEOBIOGEOGRAPHIC IMPLICATIONS

Abstract:  New material of a long-snouted dyrosaurid has been discovered in the Paleocene of Morocco. It consists of a well-preserved skull with embedded mandible and four dorsal vertebrae. The particularly elongate snout, proportionally the longest of all known dyrosaurids, allows precise identification of this material as Atlantosuchus coupatezi Buffetaut, 1979 a , and presentation of an emended diagnosis for this species previously known only from a mandibular symphysis. A phylogenetic analysis of the dyrosaurids indicates a close relationship between A. coupatezi and Rhabdognathus . It also confirms a previous hypothesis that Congosaurus is distinct from Hyposaurus . It is more closely related to Atlantosuchus than Hyposaurus . The analysis also allows palaeobiogeographic interpretations to be made. Dyrosaurids ranged from North Africa to other areas. They were rare during the Maastrichtian and endemic to each continent at this time. Competition with large marine reptiles, such as mosasaurs, limited their dispersal during the Late Cretaceous. The disappearance of these rivals during the 'K-T crisis' enabled their diversification and widespread dispersal during the Paleocene, with the same genera present on several continents.     

A NEW SPECIES OF THE SPHENODONTIAN REPTILE CLEVOSAURUS FROM THE LOWER JURASSIC OF SOUTH WALES

Abstract:  Small reptiles from the Early Jurassic Pant 4 fissure fill in Glamorgan, South Wales (St. Bride's Island, Pant Quarry), were formerly provisionally attributed to three species of sphenodontian lepidosaurs. A re-analysis, aided by new material, has found this herpeto-fauna to consist almost exclusively of a single new species, Clevosaurus convallis sp. nov . , with only one specimen referable to Sphenodontia incertae sedis . Clevosaurus is known from the Upper Triassic and Lower Jurassic in various parts of the world, but C. convallis represents the first occurrence of the genus in the Jurassic of Britain. The material is fragmentary but includes numerous premaxillae, maxillae, dentaries and palatines, and the new species is distinguished by the unique combination of six large additional dentary teeth and a very short nasal process of the premaxilla, along with the diagnostic Clevosaurus features.     

A NEW TEREBRATULID BRACHIOPOD SPECIES FROM THE SIEGENIAN OF THE DRA VALLEY, MOROCCO, AND ITS STRATIGRAPHIC, PALAEOGEOGRAPHIC AND PHYLOGENETIC SIGNIFICANCE

Abstract:  A new terebratulid brachiopod species, Rhenorensselaeria jansenii , has been identified in the Merzâ-Akhsaï Formation of the Dra Valley, Morocco, and the Grauwacke de Montguyon of the Amorican Massif, France. It is compared with the other known species of Rhenorensselaeria from Europe, Rh. strigiceps and Rh. demerathia , as well as with Rh. macgerriglei from North America, from which it differs in being larger and having coarser costae. Its possible life habit in clusters and its fossil community are compared with those of Rh. strigiceps from the Rheinisches Schiefergebirge ('Rhenish Slate Mountains'), Germany, which it most resembles. A new phylogeny of the subfamily Rhenorensselaerinae is constructed. The close phylogenetic relationship between Rh. jansenii and Rh. strigiceps confirms close palaeobiogeographical relationships between North Africa, France and the Rheinisches Schiefergebirge as well as a wider relationship between Central Europe and Gaspé, eastern Canada, during the Early Devonian. Taxa of Rhenorensselaeria are mainly restricted to the Middle and Upper Siegenian, although rare individuals have been found in the Lower Emsian of Central Europe and North America. Because of their abundance in the Dra Valley and Rheinisches Schiefergebirge and their short life span, rhenorensselaerid taxa can be regarded as important stratigraphical markers of Middle–Late Siegenian and Early Emsian sediments in North Africa and Central Europe.     

基于rDNA序列分析的湖北克鲁维酵母系统发育地位探讨

国内于20世纪90年代初曾描述过两个克鲁维酵母新种:中国克鲁维酵母(Kluyveromyces sinensis M. X. Li et al.)和湖北克鲁维酵母(Kluyveromyces hubeiensis M. X. Li et al.),二者均分自湖北神农架自然保护区。前者已被国际酵母菌分类学研究者接受和承认,而后者却一直被忽视。本文根据小亚基(18S) rRNA基因、大亚基(26S) rRNA基因D1/D2区和转录间区(ITS)序列分析,对K. hubeiensis进行了分子系统学研究。结果显示,K. hubeiensis代表一个具有充分分子系统学数据支持的独立种,该种与Saccharomyces spencerorum和Kluyveromyces lodderae形成一个高支持率的分枝,且与前者更近缘。本研究还显示,K. sinensis与Saccharomyces naganishii具有很近的亲缘关系。鉴于目前仅依靠序列分析对Kluyveromyces和Saccharomyces及其它相关属进行调整尚不现实,故建议仍维持这两个属的传统概念,并继续使用原种名。     

MARINE REPTILES FROM THE LOWER CRETACEOUS OF SOUTH AUSTRALIA: ELEMENTS OF A HIGH-LATITUDE COLD-WATER ASSEMBLAGE

Abstract: The Lower Cretaceous rocks of South Australia have yielded a diverse marine reptile assemblage of up to five families of plesiosaur (including a new cryptoclidid or cimoliasaurid, indeterminate elasmosaurids, a possible polycotylid, rhomaleosaurids, and pliosaurid) and one family of ichthyosaur (ophthalmosaurid). Other common associated vertebrates include chimaerids and osteichthyans. Sharks, dipnoans and dinosaurs are uncommon and marine turtles are notably absent. The main fossil‐producing strata belong to the Lower Aptian–Lower Albian Bulldog Shale although the Upper Albian Oodnadatta Formation has produced isolated elements. Both these units comprise finely laminated shaly mudstones and claystones deposited in a transgressive shallow coastal, epicontinental marine environment. Estimates of palaeolatitude place South Australia between 60° and 70°S, in the late Early Cretaceous. Sedimentary structures (including lonestone boulders and glendonites), fossils, isotope data and climatic modelling also indicate that seasonally cool–cold conditions (possibly with winter freezing) prevailed during deposition of the Bulldog Shale. This contrasts markedly with climate regimes typically tolerated by modern aquatic reptiles but suggests that some of the South Australian Mesozoic taxa may have possessed adaptations (including elevated metabolic levels and/or annual migration) to cope with low temperatures. A high proportion of juvenile plesiosaur remains in the Bulldog Shale might also indicate that nutrient‐rich cold‐water coastal habitats functioned as both ‘safe calving grounds’ and refuges for young animals prior to their entering the open sea as adults. The occurrence of plesiosaurs and ichthyosaurs in the high‐latitude Lower Cretaceous of southern Australia, along with plesiosaurs and mosasaurs in the Upper Cretaceous of South America, Antarctica, New Zealand and the Chatham Islands, demonstrates that Mesozoic marine reptiles utilized southern high‐latitude environments over a considerable period of time, and that these records do not represent casual occupation by isolated taxa.     

四川会理早侏罗世一新的蜥脚类恐龙

记述了四川会理下侏罗统益门组的蜥脚类化石。经研究,将化石归于马门溪龙科,建立新属新种何氏通安龙Tonganosaurus hei gen.et sp.nov.。通安龙具有进步蜥脚类的特点:颈椎细长、荐前椎发育侧凹、前肢较长,为后肢的0.80等;同时,通安龙也具有原始蜥脚类的特点:脊椎骨组织坚实不中空、肱骨和股骨骨干粗而圆。从国内外已有的资料看,原始蜥脚类主要发现于侏罗纪早期,而进步蜥脚类则主要发现于侏罗纪中晚期。由于通安龙兼具原始蜥脚类和进步蜥脚类的特点,且时代为早侏罗世,因此,通安龙化石材料的发现对中国西南地区早期蜥脚类的系统演化研究具有重要的意义。     

基于BDNF和NT-3基因部分序列探讨爬行动物系统发生中的若干问题及扬子鳄分类地位

通过两个核基因NT-3基因(约740 bp)和BDNF基因部分序列(约720 bp)的分析,对爬行动物的系统发生关系中鳄类与鸟类和哺乳类系统发生关系、龟类在爬行动物系统发生中的位置以及扬子鳄属的划分等问题进行探讨.结果表明,在NT-3基因序列中,有307个位点存在变异(约为总位点数的47.3%),BDNF基因序列有256个变异位点(约为38.79%);构建的分子系统树显示,NT-3和BDNF基因以及两序列合并数据后所得系统树的拓扑结构均支持鳄类和鸟类聚为一支构成姐妹群,鳄类与蜥蜴类尽管在形态上非常相似,但它们的亲缘关系仍然较远;同时支持把龟鳖类作为鳄类和鸟类支系的姐妹群,支持把蜥蜴类(有鳞类)放在爬行类系统发生树的基部,而不是龟鳖类作为现代爬行类中最基部的1支.对扬子鳄分类地位的研究结果支持在现存的鳄类中扬子鳄与密西西比鳄的亲缘关系较近的结论.     

PHYLOGENETIC POSITION OF THE OOCYSTACEAE (CHLOROPHYTA)

The complete 18S rRNA gene sequences of three Oocystis A. Braun species (Oocystaceae) and three other chlorococcal algae, Tetrachlorella alternans (G. M. Smith) Korš. (Scenedesmaceae), Makinoella tosaensis Okada (Scenedesmaceae), and Amphikrikos cf. nanus (Fott & Heynig) Hind. (Chlorellaceae) were determined and subjected to four different phylogenetic analysis algorithms. Independent of the reconstruction method, these taxa clustered together as a monophyletic group (Oocystaceae) within the Trebouxiophyceae. This result was supported by high bootstrap values. A comparison of morphological data with the phylogenetic reconstructions indicated that the evolution of Oocystaceae was accompanied by a reduction in the number of plastids. This study fully supports the taxonomic assignment of the Oocystaceae as a distinct family. The diacritic criterion that the cell walls are composed of several cellulose layers with perpendicular fibril orientations is in accordance with the molecular data.     

PHYLOGENETIC RELATIONSHIPS OF SPECIES OF UNCERTAIN TAXONOMIC POSITION WITHIN THE ACROCHAETIALES-PALMARIALES COMPLEX (RHODOPHYTA): INFERENCES FROM PHENOTYPIC AND 18S rDNA SEQUENCE DATA1

Nucleotide sequences of the small-subunit ribosomal RNA gene ( 18S rDNA ) were newly determined for four members of the related rhodophyte orders Palmariales and Acrochaetiales and were compared by neighbor-joining and parsimony analyses with four previously published sequences from these orders. A published rDNA sequence from Nemalion helminthoides ( Velley in Withering ) Batters ( Nemaliales ) and a gene sequence determined herein for Nothocladus nodosus Skuja ( Batrachospermales ) were used as outgroups. Sequences were very similar within the Palmariales with a maximum difference of 13 nucleotides out of 1772 between members of the families Palmariaceae and Rhodophysemataceae. Despite similarities in life history, the acrochaetioid algae Rhodo-chorton purpureum ( Lightfoot ) Rosenvinge and Rhodothamniella floridula ( Dillwyn ) J. Feldmann in Christensen were phylogenetically separated with R. purpureum affiliated weakly with Acrochaetiales, and R. floridula forming a sister branch unequivocally to palmarialean algae of the families Rhodophysemataceae and Palmariaceae . Rhodothamniella floridula is postulated on both molecular and phenotypic grounds ( encompassing biochemical and anatomical characters, and life history features ) to represent an early lineage, Rhodothamniellaceae fam. nov., in the Palmariales. The family Rhodophysemataceae appeared paraphyletic in the sequence analyses, but a monophyletic Rhodophysemataceae could not be rejected by Templeton-Felsenstein or Kishino-Husegawa tests, and the family was clearly monophyletic in analysis of the phenotypic data. The earlier tentative placement of Rhodophysemataceae in the Palmariales rather than Acrochaetiales was confirmed .     

四川盆地自流井组东岳庙段植物化石及下-中侏罗统的界线

对采自四川盆地云阳一带自流井组东岳庙段14属18种植物化石进行了研究,其中描述1个新种Stachypteris? anomala Meng(sp．nov.)和1个首见于区内的种Klukia exilis(Phillips)。东岳庙段植物组合的重要分子是从下伏珍珠冲段延续而来的,这表明此组合基本承袭了珍珠冲段的组合面貌。依据Dictyophyllum nilssoni,D．nathorsti,Otozamites hsiangchiensis等尚未见于中侏罗世和自流井组明显分为两大沉积旋回,指出东岳庙段的时代属早侏罗世托尔期(Toarcian)和四川盆地下-中侏罗统的界线以划在自流井组东岳庙段与马鞍山段之间为宜。     

OCTOCORALLIAN AND HYDROID FOSSILS FROM THE LOWER ORDOVICIAN OF WALES

Abstract:  Octocorallian and hydroid fossils are described from the Lower Ordovician (Arenig Series) of Wales. They include gorgoniids that are the earliest known fossils of this group: Petilavenula varifurcata gen. et sp. nov. and P. surculosa gen. et sp. nov. Pennalina crossi gen. et sp. nov. is probably also a gorgoniid but may be a hydroid. A new hydroid, Pontifennia gracilis gen. et sp. nov., is also described.     

PHYLOGENETIC POSITION OF KOLIELLA (CHLOROPHYTA) AS INFERRED FROM NUCLEAR AND CHLOROPLAST SMALL SUBUNIT rDNA

The phylogenetic position of Koliella , a chlorophyte characterized by Klebsormidium type cell division, was inferred from analyses of partial 18S rDNA and partial 16S rDNA. Parsimony and distance analyses of separate and combined data sets indicated that the members of Koliella belonged to Trebouxiophyceae, and high decay indices and bootstrap values supported this affinity. However, the genus appeared to be polyphyletic. Koliella spiculiformis , the nomenclatural type of the genus, was allied with Nannochloris eucaryota and the "true" chlorellas ( Chlorella vulgaris , C. lobophora , C. sorokiniana , and C. kessleri ). The close relatives of Koliella longiseta (≡ Raphidonema longiseta ) and Koliella sempervirens appeared to be Stichococcus bacillaris and some species traditionally classified in Chlorella that were characterized by the production of secondary carotenoids under nitrogen-deficient conditions. This clade was also supported by the presence of a relatively phylogenetically stable group I intron (1506) in the 18S rRNA gene. Because of the presence of Klebsormidium type cell division, some authors regarded the members of Koliella as closely related to charophytes. Molecular analyses, however, did not confirm this affinity and suggested that a Klebsormidium type cell division is homoplastic in green plants.