贵州清镇早寒武世早期藻类化石

从贵州清镇阿坝寨震旦系一寒武系界线剖面,寒武系底界附近的燧石岩石薄片中,发现的一种保存很好的藻类化石——一种内部具浓密胶状物质的多细胞球形群体化石。它不同于以往在前寒武纪发现的所有藻类化石,故建新属 Symphysosph(?)era gen.nov.(属型种 Symphy-sosphaera radiaalis gen.et sp.nov.)。文中详细比较了新属和几个已知属的区别及可能的亲缘关系。     

贵州剑河中寒武世中期甲劳组水母状化石的发现

贵州剑河革东镇八郎村南甲劳组中部钙质白云岩中新近发现的具有粗强放射状辐管的水母状化石和其下凯里组中具细辐管及同心环的拟轮盘水母(Pararotadiscus)有明显区别,属于伊尔东钵科(Eldoniidae)。其层位晚于中寒武世早期凯里生物群中拟轮盘水母(Pararotadiscus)层位1个化石带,属中寒武世中期,是该类化石在中国的最高层位,相当于北美布尔吉斯页岩生物群中Eldonia化石层位。     

安徽淮南早寒武世蠕虫化石的发现

Ｐａｌａｅｏｓｃｏｌｅｘｈｕａｉｎａｎｅｎｓｉｓｓｐ．ｎｏｖ．是我国华北地区寒武纪地层中首次发现的蠕虫化石，也是我国寒武纪地层中所发现的蠕虫化石的最高层位。     

贵州早-中寒武世凯里组类似苔藓植物化石(英文)

贵州台江早-中寒武世凯里组保存大量的生物化石,它构成了寒武纪重要的生物群之一——凯里生物群。在凯里生物群中保存有丰富的碳质薄膜藻类化石,新发现类似苔藓植物化石(Parafunaria sinensis Yang(gen.et sp.nov)),它具有藓类植物所拥有的典型的叶状体轮生现象、孢朔、孢朔柄和复杂的根系特征。推测它是藓类植物祖先,它为进一步研究藓类植物和陆生高等植物的起源和演化提供了新的线索。     

贵州早-中寒武世凯里组类似苔藓植物化石

贵州台江早-中寒武世凯里组保存大量的生物化石,它构成了寒武纪重要的生物群之一--凯里生物群.在凯里生物群中保存有丰富的碳质薄膜藻类化石,新发现类似苔藓植物化石(Parafunaria sinensis Yang(gen.et sp.nov)),它具有藓类植物所拥有的典型的叶状体轮生现象、孢朔、孢朔柄和复杂的根系特征.推测它是藓类植物祖先,它为进一步研究藓类植物和陆生高等植物的起源和演化提供了新的线索.     

云南海口早寒武世褐藻化石新知

主要报道了产自云南海口耳材村早寒武世筇竹寺组玉案山段澄江生物群中的褐藻化石－拟点叶藻（Punctariopsis latifolia gen.et sp.nov.)简单拟点叶藻（Punctariopsis simplex gen.etsp.nov.)和古德带藻（Vendotaenia cf.antiqua Gnilovskaya)3种。这些化石丰富了澄江生物群物种的多样性,为研究该群生物爆发性演化提供了新的证据。同时通过对现生褐藻和褐藻化石形态学的比较研究,表明化石属和现代属在系统演化上可能有较密切的亲缘关系,并进一步证明了澄江生物群在云南海口地区发生于一个潮间带和亚潮带的海水环境。     

昆明海口早寒武世澄江生物群中叶状红藻化石

主要报道了采自云南省昆明市海口马房村鞍山早寒武世筇竹寺组玉案山段澄江生物群中的叶状红藻-似红叶藻(新属、新种)(Paradelesseria sanguinea Xu,gen.et sp.Nov.).通过比较形态学研究,探讨了该宏观化石藻类的分类归属与亲缘关系,进一步丰富了澄江生物群生物物种多样性的认识,并为研究早寒武世生物演化及其古环境提供了新的化石证据.同时,通过对现生红藻的比较研究,进一步证明了澄江生物群在云南海口地区发生于一个水深在30 m以上的亚潮带和下潮间带的海水环境.     

昆明海口早寒武世澄江生物群中叶状红藻化石

主要报道了釆自云南省昆明市海口马房村鞍山早寒武世筇竹寺组玉案山段澄江生物群中的叶状红藻-似红叶藻(新属、新种)(Paradelesseria sanguinea Xu,gen.et sp.Nov.)。通过比较形态学研究,探讨了该宏观化石藻类的分类归属与亲缘关系,进一步丰富了澄江生物群生物物种多样性的认识,并为研究早寒武世生物演化及其古环境提供了新的化石证据。同时,通过对现生红藻的比较研究,进一步证明了澄江生物群在云南海口地区发生于一个水深在30m以上的亚潮带和下潮间带的海水环境。     

湖北秭归茅坪镇下茶庄剖面石牌动物群初探*

报道湖北秭归长江以南茅坪镇下茶庄剖面发现的寒武系下部(第2统第4阶)石牌动物群。该剖面石牌组出露良好,顶底界线清楚,总厚度208m。初步采集结果表明该剖面具有较大的开采潜力,化石数量上以腕足动物和软舌螺为主,同时还包括数量较多的三叶虫、双瓣壳节肢动物、开腔骨类和少量的鳃曳动物等,其中的腕足动物保存良好,数量丰度较大,壳体多以密集立体保存的内模形式出现,这是石牌组腕足动物大量壳体化石的首次报道。化石采集发现鳃曳动物与腕足动物可在相同的层面同时出现。与澄江动物群鳃曳动物化石相比,下茶庄剖面鳃曳动物的环纹保存的立体程度明显较强,但还未见到任何吻部和肠道结构保存。石牌动物群最早发现于长江以北宜昌三峡人家旅游风景名胜区内的王家坪剖面,但该地区石牌组覆盖严重,顶底未见出露,使王家坪剖面石牌动物群的后续研究存在较大困难。因此,石牌动物群在下茶庄剖面的发现和进一步采集和研究对深入揭示石牌动物群的组成、富集层位、群落结构和地理分布范围有重要的意义。     

龙凤山藻在澄江早寒武世生物群中的发现

主要报道了产自云南昆明海口耳材村早寒武世筇竹寺组玉案山段澄江生物群中可能为漂浮生长的宏观藻类化石-心型龙凤山藻（新种）（Longfengshania cordata sp.nov.)和中华豆芽藻（新属、新种）（lantulaformis sinensis gen.et sp.nov)。这些化石的发现进一步显示了澄江生物群种物多样性,为揭示该生物群爆发性演化提供了新的证据。通过对龙凤山藻属亲缘关系的深入比较研究,进一步证明该类化石应归属宏观藻类以及它们遗传上的稳定性、演化上的保守性和环境上的适应性。     

龙凤山藻在澄江早寒武世生物群中的发现

主要报道了产自云南昆明海口耳材村早寒武世筇竹寺组玉案山段澄江生物群中可能为自由漂浮生长的宏观藻类化石--心型龙凤山藻(新种)(Longfengshania cordata sp. nov.)和中华豆芽藻(新属、新种)(Plantulaformis sinensis gen. et sp. nov.).这些化石的发现进一步显示了澄江生物群物种多样性,为揭示该生物群爆发性演化提供了新的证据.通过对龙凤山藻属亲缘关系的深入比较研究,进一步证明该类化石应归属宏观藻类以及它们遗传上的稳定性、演化上的保守性和环境上的适应性.     

EDIACARAN AND CAMBRIAN INDEX FOSSILS FROM SONORA, MEXICO

Abstract:  The Cambrian index fossil Treptichnus pedum is reported from the Puerto Blanco Formation near Pitiquito, Sonora, Mexico, and new occurrences of the Neoproterozoic index fossil Cloudina are reported from the underlying La Ciénega Formation. Considered together, these fossils constrain the location of the Ediacaran/Cambrian boundary in Mexico. The suite of fossils in this sequence is important because it provides an independent biostratigraphic datum for constraining the position of Laurentia during the onset of metazoan diversification, for testing proposed lithostratigraphic correlations among western North American Neoproterozoic–Cambrian successions, and for testing regional tectonic paradigms such as the Mojave-Sonora Megashear hypothesis.     

贵州麻江地区寒武纪杷榔动物群的群落组成和生态空间分析*

寒武纪特异埋藏化石库保存了海洋生物群落最原始的生态结构, 为群落生态研究提供了宝贵材料。贵州寒武纪斜坡相区的杷榔动物群(第4期)具有较高的生物多样性, 但定量生态学研究相对薄弱。本研究对贵州麻江地区杷榔动物群的新产地平定剖面进行化石采集和分类统计, 并运用多元数理统计方法开展定量化分析。鉴定出腕足动物、海绵动物、刺胞动物、节肢动物、软舌螺动物、古虫动物、开腔骨动物和曳鳃动物8个化石门类, 计31属33种, 划分出12种生态类型。其中, 腕足动物具有最高的个体丰度(占比61.5%), 节肢动物物种分异度最高(占比60%), 群落以底栖固着生态类型为主, 游泳捕食为辅。对比分析结果显示, 寒武纪海洋群落具有空间异质性, 且节肢动物在影响群落组成和生态空间利用上起决定性作用。随水体深度增加, 海洋生态群落中的表栖类群出现明显扩张, 也体现了环境对群落面貌的塑造作用。     

AN ORDOVICIAN LOBOPODIAN FROM THE SOOM SHALE LAGERSTÄTTE, SOUTH AFRICA

Abstract:  The first lobopodian known from the Ordovician is described from the Soom Shale Lagerstätte, South Africa. The organism shows features homologous to Palaeozoic marine lobopodians described from the Middle Cambrian Burgess Shale, the Lower Cambrian Chengjiang biota, the Lower Cambrian Sirius Passet Lagerstätte and the Lower Cambrian of the Baltic. The discovery provides a link between marine Cambrian lobopodians and younger forms from the Silurian and Carboniferous. The new fossil preserves an annulated trunk, lobopods with clear annulations, and curved claws. It represents a rare record of a benthic organism from the Soom Shale, and demonstrates intermittent water oxygenation during the deposition of the unit.     

Cambrian spiral-plated echinoderms from Gondwana reveal the earliest pentaradial body plan

Echinoderms are unique among animal phyla in having a pentaradial body plan, and their fossil record provides critical data on how this novel organization came about by revealing intermediate stages. Here, we report a spiral-plated animal from the early Cambrian of Morocco that is the most primitive pentaradial echinoderm yet discovered. It is intermediate between helicoplacoids (a bizarre group of spiral-bodied echinoderms) and crown-group pentaradiate echinoderms. By filling an important gap, this fossil reveals the common pattern that underpins the body plans of the two major echinoderm clades (pelmatozoans and eleutherozoans), showing that differential growth played an important role in their divergence. It also adds to the striking disparity of novel body plans appearing in the Cambrian explosion.     

全尾宽背虫Bathynotus holopygus(Hall,1859)在贵州剑河八郎寒武系凯里组的首次发现及意义

宽背虫属Bathynotus(Hall,1859)广泛分布于劳伦古大陆、中国华南地区、澳大利亚和西伯利亚,为寒武纪第二世末期最重要的标志性三叶虫之一,已成为寒武系划分的重要指示化石。其模式种B. holopygus以其狭长的颊刺、胸轴宽,第11节肋刺巨大,第12、13节肋刺不发育为主要特征;具有很强的地域性,仅分布于华南和北美,在华南主要见于寒武系扬子区与江南区之间过渡区的黔东地区。B. holopygus产出地层延限较窄,仅见于寒武系第二统第四阶顶部。本文所描述的部分标本采自贵州剑河八郎苗板坡剖面苗岭统及乌溜阶界线之下2m左右,是在该地的首次报道,也是全球仅有的第4个产地。笔者通过数理统计值分析进一步描述B.holopygus的特征和发育趋势,为进一步属种研究提供新材料;根据新发现的唇瓣标本进一步推测其唇瓣与腹边缘为愈合状态。     

Epithelial moulds on the shells of the early Palaeozoic brachiopod Lingulella

A fine hexagonal network of microscopic ridges has been discovered on the internal shell surface of the cosmopolitan Lower Palaeozoic inarticulate genus Lingulella. The micro-ornamentation has been recognised on all well-preserved specimens examined, from Cambrian and Ordovician successions in Ireland, North America, Gt. Britain, Spitzbergen, and China. Examination of the mantle of the related Recent genus Lingula revealed that the outer epithelial cells are arranged in a hexagonal close-packed pattern comparable in size and form to the micro-ornamentation in the fossil shells. This fact, along with the discovery of a polygonal pattern on some organic layers in the Lingula shell, suggests that the micro-ornamentation in fossil Lingulella is the mould of the outer epithelium responsible for shell secretion. No trace of epithelial moulds has yet been found in specimens of Lingula from younger Palaeozoic successions. This difference may prove to be a useful diagnostic feature in distinguishing linguloid inarticulates from one another. Epithelial moulds , Lingulella, Palaeoglossa, Lingula, Cambrian, Ordovician, Recent.     

New Discoveries of Phaeophycean Fossils in the Early Cambrian, Haikou,Kunming,Yunnan,Southwest China

The paper deals with the new phaeophycean fossils in the Early Cambrian from Chengjiang Biota at Ercai Village of Haikou, Kunming, Yunnan, Southwest China. Three new taxa, Punctariopsis latifolia gen. et sp. nov., P.simplex gen. et sp. nov. and Vendotaenia cf. antiqua Gnilovskaya are described here in detail. These new findings show that the Chengjiang Biota is high in species diversity of fossil algae and might offer new evidence for a better understanding of the Cambrian explosive biological evolution. The fossil genus described here is found to have a close relationship with the living Punctaria based on similar morphology. The results suggest that the Chengjiang Biota in Haikou area of Kunming was living in an intertidal and subtidal seawater environment.     

节肢动物吐卓虫咬痕化石在云南昆明附近寒武纪早期关山生物群的发现及意义*

本文报道了一块来自云南省昆明市附近寒武纪第二世第四期关山生物群具咬痕的双瓣壳节肢动物吐卓虫 (Tuzoia)化石, 系吐卓虫咬痕化石在全球范围的首次发现。该发现证实作为主动捕食者的吐卓虫很可能被大型捕食者(如奇虾类或莱德利基虫类三叶虫等)捕食, 说明寒武纪早期的海洋生物群落已经具有高度复杂化的食物链, 为进一步了解吐卓虫的生态位及深入探讨寒武纪大爆发时期海洋生态系统食物网结构提供了新的信息。     

The origin of crustaceans: new evidence from the Early Cambrian of China.

One of the smallest arthropods recently discovered in the Early Cambrian Maotianshan Shale Lagerstätte is described. Ercaia gen. nov. has an untagmatized trunk bearing serially repeated biramous appendages (long and segmented endopods and flap-like exopods), a head with an acron bearing stalked lateral eyes and a sclerite and two pairs of antennae. The position of this 520 million-year-old tiny arthropod within the Crustacea is supported by several anatomical features: (i) a head with five pairs of appendages including two pairs of antennae, (ii) highly specialized antennae (large setose fans with a possible function in feeding), and (iii) specialized last trunk appendages (segmented pediform structures fringed with setae). The segmentation pattern of Ercaia (5 head and 13 trunk) is close to that of Maxillopoda but lacks the trunk tagmosis of modern representatives of the group. Ercaia is interpreted as a possible derivative of the stem group Crustacea. Ercaia is likely to have occupied an ecological niche similar to those of some Recent meiobenthic organisms (e.g. copepods living in association with sediment). This new fossil evidence supports the remote ancestry of crustaceans well before the Late Cambrian and shows, along with other fossil data (mainly Early Cambrian in China), that a variety of body plans already coexisted among the primitive crustacean stock.