论寒武纪三叶虫节头虫属：概念和异名

节头虫属(Genus Arthricocephalus)的概念一直较为混乱,在为它的模式种乔氏节头虫(Arthricocephalus chauveaui)指定"选模"后,又进一步加剧。经对A.chauveaui的原始手标本上保存的所有三叶虫研究后,发现命名者Bergeron所附A.chauveaui的唯一图片,依据的是其中一枚背壳,特征吻合,从而认定该背壳是A.chauveaui的正模,代表了模式种和节头虫属的概念,是该种和该属名称的载体。也表明为A.chauveaui建立"选模",既无必要,也违背命名者的本意。而且选择一个不归属于A.chauveaui的标本来代表该种、该属的概念,就更不妥当。经研究,手标本上的三叶虫不是同一个种,而是隶属于三个不同种,这三个种又应归属于三个不同的属,即Arthricocephalus,Oryctocarella和Duyunaspis。A.chauveaui"选模"头盖并不属于该种,应归属于Oryctocarella duyunensis。研究还表明,有三个分类单元是Arthricocephalus的晚出异名,即Arthricocephalus(Arthricocephalites)Chien et Lin in Lu et al.,1974,Haliplanktes Blaker et Peel,1997,和Arthricocephalites Chien et Lin sensu Yuan et al.,2002。     

贵州剑河寒武系清虚洞组掘头虫类三叶虫的发现

贵州剑河八郎寒武系黔东统清虚洞组由泥岩和灰岩组成,厚约300m,沉积相属于黔东陆棚深水过渡相区沉积类型,不同于黔西以浅水台地相白云岩和灰岩为主的典型清虚洞组类型。该组三叶虫化石丰富,包括莱德利基虫目Redlichia(Redlichia)guizhouensis,R.(R.)nobilis;褶颊虫目对沟虫科Eoptychoparia jinshaensis,Antagmus dapingensis,褶颊虫科Nangaops brevis;耸棒头虫目叉尾虫科Olenoides hupeiensis,Kootenia sp.,以及掘头虫类中的掘冠虫科Ovatoryctocara sp.,掘头虫科Changaspis elongata,C.cf.elongata和飞龙山虫科Duyunaspis cf.duyunensis;共计9属7种2相似种及2未定种。本文描述了其中具重要地层意义的掘头虫类三叶虫3属4种,包括2未定种。结果表明,在黔东清虚洞组发现的掘头虫类Changaspiselongata和Duyunaspis cf.duyunensis,此前仅报道于该组之下的杷榔组,现这两种的层位可上延至清虚洞组上部;同时显示该组Ovatoryctocara sp.和凯里组下部的Ovatoryctocara granulata比较相似,有可能是Ovatoryctocara granulata的祖先种。掘头虫类三叶虫的新资料将有助于促进国际寒武系第3统底界层型剖面及点位(GSSP)的进一步研究。     

贵州剑河八郎寒武系“清虚洞组”的Redlichia及其地层意义

贵州境内寒武系黔东统都匀阶清虚洞组富含具有重要地层意义的三叶虫莱得利基虫,前人据此将该组由下而上划分为2个三叶虫带:Redlichia(Pteroredlichia)murakamii-Hoffetella-Eoptychoparia组合带和Redlichia(Redlichia)guizhouensis-Redlichia(Redlichia)nobilis富集带。对黔东剑河八郎地区松山剖面非典型的"清虚洞组"中大量的莱得利基虫化石进行了初步研究,根据分类和属种延限,识别出Redlichia(Pteroredlichia)murakamii带和其上的Redlichia(Redlichia)guizhouensis-Redlichia(Redlichia)nobilis组合带。Redlichia(Pteroredlichia)murakamii带的底界可下延至下伏地层杷榔组中上部,但带内未发现常见于黔北地区典型清虚洞组的Hoffetella。剑河八朗松山剖面"清虚洞组"上述两个莱得利基虫化石带可以分别与此前建立的两个掘头虫三叶虫带Arthricocephalus chauveaui带和Protoryctocephalus arcticus带对应,进而为斜坡相区的"清虚洞组"与浅水台地相区同期地层的生物地层对比提供化石依据。     

贵州剑河寒武系黔东统杷榔组沉积环境 及生物地层再研究 ——以剑河交榜剖面为例

贵州剑河交榜剖面杷榔组顶底完整,三叶虫序列完整,产出掘头虫类三叶虫5属7种。其中Arthricocephalus chauveaui Bergeron,1899,Changaspis elongata Lee in Chien,1961,Arthricocephalites jishouensis(Zhou in Zhou et al.),1977,3个种也出现在北美格陵兰的Henson Glatsche组,提供了三叶虫全球对比的重要信息。其中A.chauveaui在交榜剖面杷榔组底部4 m首现,延伸至近顶部278 m。交榜剖面杷榔组岩石地层、生物地层和年代地层研究信息表明该剖面更适合作杷榔组岩石地层标准剖面,该剖面应是A.chauveaui首现点位定义的都匀阶界线层型剖面。可能是全球寒武系第4阶具有竟争潜力的界线层型剖面。     

高肌虫的个体发育及性双形特征

行蜕壳式增长的节肢动物个体发育及性双形特征的研究必须建立在其化石种群结构的恢复之上。简单的数理统计是揭示其种群结构特征的钥匙:鉴别是否属正常化石种群,确定蜕壳期数,解释早期幼壳高死亡率与其化石低保存牢的统一。高肌虫个体发育常表现为六至七期明显的蜕壳阶段,蜕壳期间壳体增长率常在性成熟期有显著的减小趋势。物种的正确鉴定及性双形特征的辨识也只有通过个体发育研究才能得到合理的解决;物种在个体发育过程中表现出来的性伏变化,为研究谱系的演化趋向提供重要依据。这种数理统计方法无疑对三叶虫、介形虫等其他节肢动物的个体发育及性双形研究也完全适用。     

辽西凌源全身长有羽毛奔龙化石的再研究

对辽西凌源发现的全身长有羽毛的奔龙化石 (NGMC91) (Ji等 ,2 0 0 1)进行了再研究。根据头颅和头后骨骼的特征 ,其应归于中国鸟龙属 (SinornithosaurusXuetal.,1999)。由于研究的材料是一块处于非成年期的标本 ,虽然其有些特征明显与千禧中国鸟龙有别 ,但仍难以确定这些差异是否受个体发育的影响。因此 ,文中仍将其作为未定种 ,置于中国鸟龙属中。此外 ,文章还简要讨论了羽毛的发生和早期演化 ,认为羽毛出现的初始功能就是为了保持体温 ,与后期的飞行功能无关     

浙西、赣东北寒武系下统荷塘组岩石特征及沉积环境分析

为了探索沉积相与生物相的关系,1963—64年间,李蔚秾、薛耀松、丘金玉、俞从流、杨万容、唐天福和朱兆玲等先后对浙西、赣东北寒武系进行了三次野外调查,测制了二十多条剖面。1964—1965年,对所采集的标本进行了薄片鉴定,各剖面都作了比较系统的化学分析和光谱半定量分析,进行了初步的综合研究,编写了有关浙西寒武系若干专题和“浙西寒武系下统”的研究报告初稿,就“节头虫(Arthricocephalus)在浙西的发现”作了简     

莱得利基虫及其数新种

莱得利基虫(Redlichia)一属为下寒武纪最重要三叶虫之一,此属在地理上分布之广以及其在地质史上出现时间之长,同时代其他化石均无出其右。几十年来经中外学者各方面之研究,知其在地理上分布似远出乎一般意料之外,其地层上垂直分布似亦与其演化程序有重大关系。至於本属之个体发育,尤饶兴味,由个体发育观察,不     

许氏创孔海百合Traumatocrinus hsui的形态定量分析和个体发育过程

Traumatocrinus hsu Mu, 1949是关岭生物群的重要组成成员,以数量众多、保存精美、营假浮游生活闻名于世。笔者等通过对5件群体保存标本中的127个大小不同个体的系统描述和形态定量分析,认为T. hsui萼部与整个冠部存在异速生长的特征,个体发育过程中腕的级数和数目逐渐增加;T. hsui的个体发育可分为3个时期6个阶段,即幼年期（Ⅰ、Ⅱ）、少年期（Ⅰ、Ⅱ、Ⅲ）、成年期;幼年期：个体较小,冠高小于26 mm,腕分枝至4级;少年期：个体中等,冠高26～130 mm,腕分枝至7级;成年期：个体较大,冠高大于130 mm,腕分枝至8级。前人在关岭生物群中研究命名的Traumatocrinus hsui enormis Mu, 1949,Traumatocrinus kueichouensis Mu, 1949,Traumatocrinus uniformis Mu, 1949,Traumatocrinus sp. Mu, 1949,Traumatocrinus guanlingensis Yu et al., 2000和Traumatocrinus xinpuensis Wang et al., 2002等均为T. hsui的同种异名,其命名标本为个体发育的不同阶段或局部特征。     

许氏创孔海百合Traumatocrinus hsui的形态定量分析和个体发育过程

Traumatocrinus hsui Mu, 1949是关岭生物群的重要组成成员,以数量众多、保存精美、营假浮游生活闻名于世。笔者等通过对5件群体保存标本中的127个大小不同个体的系统描述和形态定量分析,认为T. hsui萼部与整个冠部存在异速生长的特征,个体发育过程中腕的级数和数目逐渐增加;T. hsui的个体发育可分为3个时期6个阶段,即幼年期（Ⅰ、Ⅱ）、少年期（Ⅰ、Ⅱ、Ⅲ）、成年期;幼年期：个体较小,冠高小于26 mm,腕分枝至4级;少年期：个体中等,冠高26～130 mm,腕分枝至7级;成年期：个体较大,冠高大于130 mm,腕分枝至8级。前人在关岭生物群中研究命名的Traumatocrinus hsui enormis Mu, 1949,Traumatocrinus kueichouensis Mu, 1949,Traumatocrinus uniformis Mu, 1949,Traumatocrinus sp. Mu, 1949,Traumatocrinus guanlingensis Yu et al., 2000和Traumatocrinus xinpuensis Wang et al., 2002等均为T. hsui的同种异名,其命名标本为个体发育的不同阶段或局部特征。     

Revision of the Genus Conophyllia d'Orbigny 1849(Anthozoa,Scleractinia, Triassic) and Conophyllia from the Renacuo area of Gêrzê, Tibet

There have been divergent opinions on whether Conophyllia develops synapticulae and dissepiments since its erection in 1849, with different views existing on the morphology of columella in Conophyllia.This paper presents a comprehensive review of Conophyllia, and revises the diagnosis according to new material from the Renacuo area of Gêrzê, Tibet.The revised diagnosis emphasises the following features: solitary coral; abundant radial elements subequal in thickness, lateral faces with granules and synapticulae; parietal, papillar or incompact columella, a few species lacking in columella; developed dissepiments.Individuals of Conophyllia have laminar septa of Triadophyllum type in earlier ontogenetic stages, while their septa in later ontogenetic stages are more fenestrate.The geological and geographical distribution of this genus is discussed, with five species of Conophylliafrom the Renacuo area of Gêrzê, Tibet being described and illustrated, including one new species and two in open nomenclatue.     

Dimorphism in Placenticeras mintoi from the Upper Cretaceous Bagh Beds, central India

The Upper Cretaceous Bagh Beds yield many biota of which ammonoids are particularly well known. Previously Bagh ammonoids were grouped into many genera and species within several families. The present study, however, shows that failure to recognize dimorphism and a wide range of interspecific variation within the single genus Placenticeras perhaps results in taxonomic oversplitting. Specific dimorphism in P. mintoi has been established.     

微体古生物微型计算机辅助研究系统

微体古生物微型计算机辅助研究系统是一个包括古生物化石属种数据厍、图象库、图象处理和数据采集系统以及定量分析系统在内的综合性古生物数据处理系统。其中,数据库和图象库的主要作用在于辅助化石鉴定。目前数据库和图象库包括了新生代浮游有孔虫1036个种的文字和图象资料。数据库和定量分析系统之间的数据传送非常方便,实现了对大批量古生物数据的定量分析,包括聚类分析、因子分析、瓦格纳网络分析、个体发育分析以及各种统计方法,这些分析程序都配制了相应的绘图功能,使分析结果能以直观的形式输出。定量分析有助于我们对一些“同物异名”和“异物同名”问题的厘定,并由此产生对分类问题的一些新认识。同时,定量分析有助于从定量的角度考查新生代浮游有孔虫的整体变化。     

Heterochronic evolution in the Late Cretaceous echinoid Gauthieria (Echinoidea,Phymosomatidae)

Based on representatives of the Late Cretaceous genus Gauthieria (Gauthieria radiata – Gauthieria spatulifera – Gauthieria princeps), ontogenetic trajectories within the family Phymosomatidae are described for the first time. Due to shared similarities in their ontogenetic development, an intimate evolutionary relationship must be assumed. This interpretation is most supported by analyses of the development in the ambulacral plating pattern (alternation of simple plates and compound plates), which is not commonly found among the Phymosomatoidae. This pattern, however, is present among all three species during development. The developmental trajectories of 8 further characters were included in this study (arrangement of the adapical pore pairs, number of pore pairs, pore pair numbers in ambital ambulacral plates, number of interambulacral plates, peristomal opening, apical opening diameter, test height, radial ornament of the areoles). The evolution in this lineage is characterised by several different heterochronic processes, which suggest a dissociated heterochronic evolution, indicating a developmental modularity. Additionally, the systematic treatment of G. princeps is discussed on account of the presented results.     

陕西岚皋地区Oktavites spiralis(螺旋奥式笔石)发育过程的初步研究

Oktavites spiralis是志留纪兰多维列统特列奇阶的笔石带化石之一,具有重要的地层意义。为更精确地描述这一属种,对产自陕西岚皋地区的Cyrtograptus lapworthi笔石带的O.spiralis不同发育阶段的标本进行了详细研究,从而对其始部发育情况有了更深入的认识。同时,对O.spiralis发育过程的研究也可以成为对该属进行精确厘定的手段之一。     

济阳坳陷深层构造及其对中新生代盆地发育的控制作用

以3D地震资料和钻井资料的解释为基础,通过对济阳坳陷深层进行构造 地层分析和构造解析,系统阐明了中、新生代各期构造运动在研究区的地质表现,确定出收缩构造系统、伸展构造系统和走滑构造系统等多期构造样式;提出印支期逆冲断层系由多条显著向NE或NNE向凸出的弧形展布断裂系组成;识别出代表燕山主期构造运动的不整合界面(Tgm),确定了J3-K1时期断陷盆地的分布格局;认为印支期逆冲断裂系统是控制本区晚中生代和新生代早期盆地发育的重要的控制性先存基底构造。在区域动力学分析的基础上探讨了该盆地复杂的叠合结构和山脉 盆地的转换过程及机制。从盆地研究的角度,揭示了华北东部中、新生代陆内动力学过程,对于研究区油气勘探实践具有重要意义。     

The first findings of fusulinids in the sections of the Sabzevar tectonic block (Iran)

The first fusulinids have been recorded from the eastern part of the Sabzevar tectonic block (Kuh-e-Ahuban Mountains, to the north of the town of Kashmar). The fusulinids have been grouped into two complexes. The first complex is represented by several species of the genus Rauserites, of probable Gzhelian age. The second complex is represented by numerous representatives of the Asselian genera Sphaeroschwagerina and Pseudoschwagerina, as well as species of the genera Schubertella, Rugosofusulina, Rugosochusenella and Praepseudofusulina. The age of these complexes is similar to that of complexes previously described from sections of Anarak (the Yazd block) and Zaladou (the Tabas block), but differ in the species composition. Many of the species present in these complexes are similar or identical to species from standard sections of Gzhelian and Asselian Stages of the Moskovian syncline and the Urals, which indicates that there were free connections between the East European and Iranian basins in Gzhelian and Asselian Stages.     

腕足类Costiferina和Stereochia属的特征、成员及其地质、地理分布

本文根据从云南西部耿马采集的大量的腕足类Stereochia属标本,以及详查资料的比较,对Stereochia属和Costiferina属的特征和成员进行了深入的讨论。通过对属种的修订,理清了两个属的地质时代和地理分布。结果表明,Stereochia属的地质历程主要是早二叠世Sakmarian期至晚二叠世Dzhulfian期;Costiferina属出现时期比Stereochia属晚,主要分布在早二叠世Baigendzinian期至晚二叠世Djulfian期。上述两属对确定冈瓦纳大陆北缘海边界有重要意义,Stereochia常与(竹蜓)类和珊瑚化石共生,生活在温暖清澈水体中。古地理上,它分布在冈瓦纳大陆北缘海边界,属于浅海地台型沉积范围;Costiferina常出现于碎屑岩中,与之共处的化石多为个体巨大、壳壁厚的Fusispirifer,很少与(竹蜓)类和珊瑚类在一起,表明它生活在冈瓦纳大陆北缘海的靠大陆一侧,这里陆源碎屑丰富,海水混浊,并相对偏冷。     

Lower Bathonian Belemnites and Biostratigraphy of the Central and Southern Parts of the East European Platform: Part 2. Cylindroteuthididae and Belemnotheutididae

Belemnites from the lower Bathonian deposits of the Russian Plate are revised and discussed on the basis of study of the two reference sections—Pletnyovka and Sokur quarries. This is the second part of the investigation dealing with representatives of the family Cylindroteuthididae, and “rostrum-less” belemnites of the family Belemnotheutididae, while members of the family Megateuthididae were discussed in detail in the first part (Ippolitov, 2018). The cylindroteuthidids are found only in the Sokur Quarry and comprise four species all assigned to the genus Pachyteuthis, including a new species, Pachyteuthis mittai sp. nov. For Belemnotheutididae, the presence of a single species Acanthoteuthis foliorostris sp. nov. is recorded, which is the first confirmed record of the genus Acanthoteuthis in the pre-Callovian strata. The study of morphological changes within Cylindroteuthididae across the succession allowed two biohorizons to be recognized and the existing belemnite-based scheme for the lower Bathonian of the Volga Region and its correlation with sections in the Pechora River basin to be updated. As the result of the revision, a complex zonal and infrazonal belemnite-based stratigraphic scheme of the lower Bathonian of the Volga Region is introduced. The presence of an endemic genus deriving from Arctic-Boreal immigrants in the lower Bathonian of the Middle Russian Sea allows the belemnite fauna of this age to be interpreted as the first isolated episode of differentiation of the Boreal-Atlantic Province in belemnites. The study of the development of the cephalopod fauna in the early Bathonian of the Russian Plate indicates a biphase formation of the meridional strait connecting the Middle Russian Sea with the Arctic basins and also supports the hypothesis of a short-term opening of a sublatitudinal Pripyat Strait during the maximum highstand.     

New record of <Emphasis Type="Italic">Plectoidothyris</Emphasis> from the Middle Jurassic Sequence of Jaisalmer Basin,Western India: Implications on the easterly brachiopod migrations

The Bathonian sediments of the Jaisalmer Basin, India host a terebratulide brachiopod Plectoidothyris which has been previously known from the Bajocian rocks of the Boreal Province. The sharp and prominent plication of the anterior commissure and increased length of costae separates the Jaisalmer specimens from other known species of the genus and the population represents an endemic species — Plectoidothyris jaisalmerensis. The population was only cursorily described earlier lacking in details of precise stratigraphic control and was wrongly assigned to a different genus. The present study is based on a large number of specimens from different localities with precise stratigraphic data, coupled with this some recent findings of time-diagnostic ammonites have helped determine the Plectoidothyris jaisalmerensis duration in the Jaisalmer Basin as the Late Bathonian. Presence of lower Jurassic Boreal brachiopod genera in the Middle Jurassic rocks of Ethiopian and Indo — Madagascan biogeographic provinces has been noticed earlier whereto Plectoidothyris is a new addition while it is also the first report of the genus from the Jurassic of India. The brachiopod migrations from the north to south of the Tethys provide evidences for opening of shallow water routes in the Tethyan seaway and are probably indicative of warmer water conditions in the Indo-Madagascan and African areas during the Middle Jurassic.