寒武纪早期澄江生物群中受创伤的中间型始莱德利基三叶虫(Eoredlichia intermedia)

三叶虫是寒武纪海洋中的常见动物,其受伤愈合现象的化石记录可以反映生态系统内物种之间竞争关系。中国华南寒武纪早期澄江化石生物群因保存软躯体构造化石而成为研究寒武纪大爆发时期古海洋生态群落的绝佳窗口,然而,澄江生物群中三叶虫受伤愈合现象的化石至今未见报道。中间型始莱德利基虫(Eoredlichia intermedia Lu,1940)是澄江生物群的常见物种,也是我国寒武系第二个三叶虫化石带的标准带化石。在2 000余枚中间型始莱德利基虫标本中,发现两枚成体标本的头甲侧边缘、颊刺和胸甲肋节保存了不同程度的残缺。据此推测,Eoredlichia intermedia在生命活动过程中曾受到碎壳型捕食动物的攻击或其他伤害而形成伤口。伤口部位边缘加厚且光滑,显示了明显的愈合痕迹。这些特征表明始莱德利基虫在受到非致死的伤害后,具备自身修复损伤的能力。这是迄今所知最为古老的,也是在澄江生物群中首次发现的三叶虫受伤并且愈合的标本,反映了寒武纪第二世第三期底栖生态系统中碎壳型捕食者和三叶虫猎物之间的军备竞赛生态关系。     

皖南寒武纪三叶虫Cheiruroides primigenius 的个体发育

描述采自皖南东至庞汪剖面黄柏岭组黄绿色页岩中的处于不同发育阶段的Cheiruroidesprimigenius标本的形态特征和各器官在个体发育过程中的变化趋势。在个体发育过程中 。     

SYSTEMATICS OF THE CAMBRIAN TRILOBITE FAMILY NEPEIDAE, WITH REVISION OF AUSTRALIAN SPECIES

Abstract:  Taxonomy of the Cambrian trilobite family Nepeidae is revised. Morphometric analyses of the genera Nepea and Penarosa demonstrate that use of proportions of linear dimensions of the cranidium to differentiate species is invalid, and that infrageneric variation is continuous. The taxonomy and biostratigraphy of all Australian species of Nepeidae is revised. Species considered valid herein include: Nepea narinosa (type species), N. tonsillata , N. nans , Penarosa retifera (type species), P. elaticeps , P. rhinodelphis , P. netenta , Loxonepea loxophrys (type species) and Ferenepea hispida (type species). Folliceps is considered to be a junior subjective synonym of Nepea , Trinepea is regarded as a junior subjective synonym of Penarosa , and Ascionepea is considered to be a junior subjective synonym of Ferenepea .     

贵州金沙寒武系牛蹄塘组的古盘虫类三叶虫

贵州金沙寒武系牛蹄塘组产出大量古盘虫类三叶虫化石,包括分离头盖、尾部和完整背甲。依据标本中具分类鉴定意义的构造特征的测量数据比值并线性拟合,结合形态学特征、个体发育趋势等特点分析,认为Tsunyidiscus armatus和Tsunyidiscus niutitangensis两个三叶虫种是有效的,支持以尾部肋区分节差异作为两个种种征判别标志。本项研究可为厘定贵州金沙地区三叶虫Tsunyidiscus序列提供可靠证据。     

中国寒武纪三叶虫生物地理趋议

寒武纪三叶虫除北疆和藏南尚无可靠报道外,在中国各地均有广泛分布。三叶虫证据表明,除兴安区的额尔古纳一兴安地体和早寒武世中天山一北山地体显示了与西伯利亚和劳伦陆块在动物群方面的密切相关外,中国寒武纪的所有板块和大部分地体（包括中及晚寒武世的中天山～北山地体）均系当时东泛冈瓦纳的重要组成部分,在生物地理上彼此密切关联。对这些属于东泛冈瓦纳的中国区块的生物地理格局的进一步探讨,主要侧重于它们台地相浅水三叶虫动物群之间的对比,特别是立足于来自动物群纪录比较完整的华南、塔里木和华北板块的证据。综合分析研究表明这些板块和有关的地体在中及晚寒武世应归属同一生物地理区,而在早寒武世则可划分为两个生物地理亚区：一个由华南、塔里木板块和安南或印支地体组成,另一仅以华北板块为代表。     

南澳大利亚Officer盆地东部下寒武统Abadiella一新种

描述采用自南澳大利亚Officer盆地东部Manya-6号钻井的下寒武统Ouldburra组的Abadiella三叶虫的一新种－Abadiella officerensis,同时指出Parabadiella是Abadiella的同义名。     

陕南早寒武世早期管柱状生物化石新发现

繁殖是生物体产生子代的现象,是生物体最基本的特征之一.最近作者在陕南宁强宽川铺地区早寒武世最早期的宽川铺生物群中发现了数十枚管柱状生物化石,首次发现这些管柱状生物化石具可能的"断裂生殖"特征.在部分管柱状生物化石上可清晰分辨出"收缢带"、"收缢纹"和"新生单节"等断裂生殖特征,据此建立可能的管柱状生物"断裂生殖"生殖发育序列.     

NEW MATERIAL OF LATE CAMBRIAN TRILOBITE FAUNA FROM THE YEHLI AREA,KAIPING BASIN,HOPEI

At Changshankou and Yehli in Kaiping Basin,the late Cambrian stratigraphy andpaIaeontology was first studied by Prof.Y.C.Sun in 1920.The following two forma-tions were then sectioned:2.Fengshan formation characterized by Prychaspis subglobosa,Mansuyia orientalis1.Changsban formation yielding Changshania conica,etc.In 1929,Y.T.Cbao,T.F.Hou and C.Y.Lee went to Yehli for a detailed mappingof the Fengshan-Weishan section,but they failed to obtain any other late Cambrian fos-     

THE UPPER CAMBRIAN TRILOBITE OLENUS AT ANDRARUM,SWEDEN: A CASE OF ITERATIVE EVOLUTION?

Abstract:  The morphological changes in four species-level lineages of the Late Cambrian trilobite Olenus from the Alum Shale at Andrarum, south-east Scania, Sweden, have been analysed with the aim of re-examining the classical study of iterative evolution by Kaufmann (1933 a ). New material comprising 647 pygidia was collected for a restudy of Olenus , and for comparison the skeletal development of 918 cephala and 568 pygidia from the associated Homagnostus obesus were included. The re-examination shows that (1) only pygidia of the O. transversus – O. truncatus – O. wahlenbergi lineage display a statistically significant directional change towards a narrower shape; (2) all other lineages, including the agnostids, show net morphological stasis; (3) hence iterative directional evolution cannot be confirmed. Based on morphological investigations it is tempting to conclude that the lineage O. transversus – O. truncatus – O. wahlenbergi represents just one species displaying gradual morphological changes. Whether this is an evolutionary or an ecophenotypic phenomenon remains uncertain. The vertical distributions of olenids and agnostids are compared by using vanadium/(vanadium + nickel) ratios from the Olenus Zone of the nearby Gislövshammar-2 drill-core. It appears that incursions of olenids were linked to increases in bottom-water oxygen levels and that Homagnostus obesus was tolerant of lower dysoxia than olenids.     

葫芦虫化石在寒武纪关山生物群中的发现及其意义

报道产自昆明高楼房的寒武纪早期关山生物群中的葫芦虫化石,这是该类动物在全球的第三例化石记录。葫芦虫化石在关山生物群的发现对了解该类动物以及寒武纪动物群生态和演化等均有着重要意义。     

HOLASPID VARIATION IN THE SOLENOPLEURID TRILOBITE PARASOLENOPLEURA GREGARIA (BILLINGS, 1865) FROM THE CAMBRIAN OF NEWFOUNDLAND

Abstract:  The Cambrian trilobite originally described as Bathyurus gregarius by Billings in 1865 is revised in the light of a new collection from what is judged to be its type locality in the Big Gully Marl Member of the Chamberlain's Brook Formation on the Cape St. Mary's Peninsula of south-east Newfoundland. Here assigned to Parasolenopleura gregaria, it is regarded as the senior synonym of Parasolenopleura cristata (Linnarsson, 1877) in the Swedish Paradoxides ( Eccaparadoxides ) insularis and P. ( Plutonides ) pinus zones, and Parasolenopleura lemdadensis Geyer, 1998 in the Moroccan Ornamentaspis frequens-Kymataspis arenosa zonal boundary beds. Among its features, important details of the relationships of the genal caeca to the eye and cephalic borders are given, as well as illustrations of the significant range of biotic and abiotic morphological variation in holaspid growth stages of the cephalon that will have some bearing on the revision of the Solenopleuridae.     

峡东地区寒武纪三叶虫Palaeolenus的新材料

对采自峡东地区宜昌、秭归等地的Palaeolenus Mansuy,1912的新材料的形态、保存状态、挤压变形以及个体发育等方面的研究,提出Megapalaeolenus Chang,1966的模式种Palaeolenus deprati Mansuy。1912是Palaeolenus Mansuy的模式种Palaeolenus douvillei Mansuy,1912的晚出异名,属名Mega palaeolenus Chang和种名Palaeolenus deprati Mansuy均应予以废弃。文中还对原归于Palaeolenus和Megapalaeolenus的种作较大的归并和修订。     

东北七鳃鳗早期发育研究

通过开展东北七鳃鳗(Lampetra morii)胚胎、卵黄囊期仔鱼和幼鱼发育研究, 系统地描述东北七鳃鳗的早期发育形态特征和生长发育规律。研究结果表明: 东北七鳃鳗的卵裂为全裂类型, 在(18±1)℃水温下, 受精卵经卵裂期、囊胚期、原肠胚期、神经胚期、头凸期、孵出前期以及孵出期, 历时11—12d孵育出仔鱼。初孵仔鱼体重为(0.00032±0.00002) g, 全长为(0.29±0.02) cm。在卵黄囊期内, 仔鱼体重和全长随日龄的增加而增长, 吻长、眼径、眼鳃间距、口笠长、鳃前长、鳃长、头长、体长、尾长和泄殖孔长均存在异速生长现象。初孵仔鱼经过约15d(卵黄囊期)发育成幼鱼, 幼鱼卵黄囊完全吸收, 消化道贯通, 形成肠道, 开始摄食。在幼鱼期, 经5 个月的培育, 幼鱼体重和全长随月龄的增加而增长, 体色逐渐加深, 5月龄幼鱼的体重和全长分别为(0.07±0.01) g和(3.87±0.32) cm。东北七鳃鳗的早期发育研究为七鳃鳗发育生物学积累基础资料, 同时也为七鳃鳗的人工增养殖提供了科学依据, 推进七鳃鳗的模式化进程。     

贵州早、中寒武世斗篷海绵科(Choiidae)的发现

本文描述了贵州遵义下寒武统牛蹄塘组生物群和台江中寒武世凯里生物群中保存完整的斗篷海绵科(Choiidae)中斗篷海绵(Choia)和小斗篷海绵(Choiaella)化石标本,共计2属2种2未定种：Choia zunyiensis sp.nov.,Choia sp.,Choiaella avata sp.nov.和Choiaella sp.。Choia分布很广．在我国下寒武统澄江生物群及北美中寒武统的四大生物群中均有产出。Choiaella原仅产于我国澄江生物群,凯里生物群中Choiaella的发现使其时代上延至中寒武世。贵州早、中寒武世斗篷海绵科的发现及研究为海绵动物的早期演化及古地理学等方面的研究提供了重要的新材料。     

安徽淮南寒武纪一新三叶虫属——Huaiaspis

安徽淮南八公山地区寒武纪毛庄-徐庄期地层出露良好,化石丰富。在老鹰山剖面徐庄组底部的紫色页岩内所采集大量三叶虫标本中发现的一种新的三叶虫,命名为Huaiaspishuainanensisgen.etsp.nov.,它代表了一个尚未描记的且科级分类位置待定的新属新种。该三叶虫特点突出,是头部特征极度消隐且不具眼、眼叶、眼脊的“盲三叶虫”。该三叶虫为小尾型后颊类,主要特征为:壳面光滑,背壳呈次椭圆形,头盖半圆形;头鞍呈钟形向前收缩;背沟浅,仅在侧光下可见;活动颊平滑宽大,具有宽阔的活动颊刺;胸部由14节组成;尾部中轴粗壮,无边缘沟。     

山东东平中寒武世三叶虫Anomocarella的完整个体

小林贞一曾经描述产自山东蒙阴的Anomocarella两个完整个体,当前描述的Anomocarella的标本产自山东东平,它比蒙阴的标本更完整。     

论我国寒武纪第二世UshbaspisPokrovskaya,1965———应用聚类分析探讨Ushbaspis种的分类*

应用聚类分析探讨我国原Metaredlichioides Chien and Yao,1974属中13个种和产于哈萨克斯坦的Ushbaspis属的模式种——Ushbaspis granulata Pokrovskaya,1965的分类。将我国原Metaredlichioides属中13个种归并和修订为4个种:Ushbaspis constricta(Chien and Yao),U.hubeiensis(Lin),U.meiziwanensis(Yin)和U.shiqianensis(Yin)。并对Metaredlichioides与Ushbaspis两个属的模式种进行定量分析,所取得的结论与张文堂(Chang et al.,1997)以定性分析提出Metaredlichioides是Ushbaspis的晚出异名的意见完全一致。     

THE LOWER CAMBRIAN EODISCOID TRILOBITE CALODISCUS LOBATUS FROM SWEDEN: MORPHOLOGY, ONTOGENY AND DISTRIBUTION

Abstract:  Several thousand disarticulated remains together with a few complete enrolled specimens of the lower Cambrian eodiscoid trilobite Calodiscus lobatus ( Hall, 1847 ) have been collected at two outcrop areas in Sweden. The material reveals new details of morphology and morphogenesis during ontogenetic development. Size-frequency analyses show that the material from the Fånån rivulet in Jämtland, central Sweden, represents a natural population dominated by juveniles, whereas the material from Gislövshammar in Scania, southern Sweden, has been sorted during postmortem transport. Three stages of protaspid development can be traced and defined as well as all subsequent ontogenetic stages for the cephalon, hypostome and pygidium. The early meraspid pygidium has a pronounced larval notch, which persists, though becoming progressively less distinct in later meraspides. The number of axial rings in the transitory pygidium increases throughout meraspid development until a third and final thoracic segment is liberated. During ontogeny the articulating half-rings are strongly developed, and both meraspides and holaspides were capable of full sphaeroidal enrollment and outstretched postures. The hypostome undergoes some dramatic modifications; in M0 the anterior margin is axe-shaped, by M1 the area of attachment greatly decreases and the hypostome becomes more elongated and pear-shaped, before attaining its adult form, which has an overall resemblance to that of polymerid trilobites. During ontogeny, the hypostome changes from a conterminant attachment to a natant condition, thereby mirroring hypostomal evolution within trilobites generally. The morphology, ontogeny, enrollment, hypostomal development and the presence of calcified protaspides suggest polymerid rather than agnostoid affinities of the eodiscoids.     

华南斜坡相寒武纪三叶虫动物群研究回顾并论我国南、北方寒武系的对比

回顾建国以来对江南斜坡带寒武纪三叶虫动物群的系统古生物学研究.分析江南斜坡带寒武纪三叶虫动物群的组成.以江南斜坡带的三叶虫研究成果为基础,讨论我国华南、华北和东北南部区的生物地层和年代地层对比.