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1.
新疆乌什下寒武统肖尔布拉克组软舌螺化石 总被引:1,自引:1,他引:1
首次描述了采自新疆乌什县乌什磷矿肖尔布拉克组中部Kepingaspis-Tianshanocephalus带中的2个软舌螺新种Conotheca xinjiangensis sp.nov.,Nitorcornus wushiensis sp.nov.和下部Ushbaspis带中的1个软舌螺未定种Adyshevitheca?sp.。这些软舌螺化石材料为研究新疆乌什地区下寒武统中部地层与邻区相当层位的对比提供了新的证据,认为肖尔布拉克组中部2个三叶虫化石带和其中的软舌螺化石相当于我国扬子地台下寒武统沧浪铺阶中部,即乌龙箐亚阶和红井哨亚阶之间,可与俄罗斯西伯利亚和哈萨克斯坦下寒武统波特姆阶(Botomian)中的三叶虫带Ushbaspis和软舌螺带Erraticornus-Nitorcornus带对比。 相似文献
2.
对采自陕西镇巴小洋剖面下寒武统西蒿坪段的似软舌螺类(hayolithelminths)化石进行了研究,描述了一新种Torellella bisulcata sp.nov.,其主要特征为:磷质管状壳体,横切面透镜状,壳管的两个宽面凸度不等,一面为弧状,另一面扁平;壳管直或微弯曲,在壳管的两个窄的侧面各具一纵向浅凹沟,壳面光滑或饰有微弱的横向纹线。简要地讨论了似软舌螺类化石的生物亲缘关系,认为迄今为止,其仍为分类位置不明的化石类别。西蒿坪段中下部产有三叶虫颊刺和颈刺,表明此段沉积地层属于下寒武统筇竹寺阶而非梅树村阶。 相似文献
3.
贵州台江中寒武世的一些软舌螺化石 总被引:2,自引:4,他引:2
该文的软舌螺标本采自贵州省台江县八郎村中寒武世地层,计有Haplophrentis?reesei,H.?carinatus,Hyolithes?cf.idahoensis,H.?cf.cariniferus,H.?sp.,Cambrovitus balangensis gen.sp.nov.,Notabititidae gen.et sp.uncertain.。其层位位于梅树村动物群和澄江动物群之上。地层时代与北美布吉斯页岩的时代相当,两地的软舌螺可直接对比。更为可贵的是在方Haplophrentis?carinatus的腹内视标本中发现了直肠和伸缩肌软体印痕。 相似文献
4.
本文首次报道Microdictyon在我国寒武纪的发现。此类化石为磷酸钙质;个体小,1-1.5mm,为半球形、椭圆形;具网格状结构的化石,归入小壳化石。文中记述的化石是用15%冰乙酸分离出来的。描述建立一新种Mierodietyon anus sp.nov..现于陕南镇巴。 相似文献
5.
该文的标本采自云南昆明、晋宁下寒武统筇竹寺组,龙陵上寒武统核桃坪组、柳水组和江苏江宁上奥陶统顶部“新开岭层”。文中描述了软舌螺化石4属5种,1未定种。其中3新属3新种,再次丰富了早古生代碎屑岩地层中的软舌螺化石,对探讨软舌在演化进程,确定时代,进行地层对比均有重要价值。 相似文献
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辽东上寒武统长山阶新三叶虫 总被引:1,自引:0,他引:1
报道产于中国辽东上寒武统长山阶三叶虫的4新属、种。其中Yingziaspis产于本溪营子北沟二道沟Changshania带,其余3新属均产于大连地区,新属Lashushania产于Kaolishania带上亚带K.pustulosa亚带,新属Guohongjunia产于Chuangia带中部;新属Wafangdiania产于Kaolishania下亚K.granulosa亚带。 相似文献
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本文描述的标本全部采自鄂西宜昌莲花沱黄鳝洞和长阳鸭子口钟鼓湾(插图1)下寒武统水井沱组。采自宜昌的标本包括2新属、2新种:Liantuoia inflata gen. et sp. nov., Huangshandongia yichangensis gen. et sp. nov.。有的与北美布吉斯页岩(Burgess Shale)产的叶虾类Proboscicaris Rolfe, Fieldia Walcott等相似,有的与角虾类Caryocaris 相似文献
10.
云南澄江下寒武统细丝海绵化石 总被引:7,自引:6,他引:7
前言澄江海绵化石群的系统分类学、生态学、埋藏学和演化生物学等问题将分为不同专题进行研究。本文是关于澄江海绵化石的第一篇报道,研究内容侧重于细丝海绵科系统分类学。细丝海绵科属于普通海绵类,为澄江海绵群体中的优势类型,也是最为原始的普通海绵类之一。它们的骨骼甚薄,主要由席状外骨层所组成。外骨层由大小不相同的两套单轴骨针纵向排列而成;大骨针互相叠接成骨棒状或互相交错排列成网状,以便起着主要的支撑作用。大骨针之 相似文献
11.
陕西,鄂西下寒武统西蒿坪段“瓶状微化石”再研究 总被引:1,自引:0,他引:1
本文展示了陕西西乡和湖北房县下寒武统西蒿坪段中的三块棘状集合体标本,论证了西蒿坪段中的所谓瓶状微化石不是原生动物,而一类接近于开腔骨类Chancelloriids的多骨片后生动物化石。将过去在西蒿坪段中描述的14属38种“瓶状微化石”合并成1属1种,即Cambrothyra ampulliformis Qian et Zhang,1983和C.truncata (Duan),1986。 相似文献
12.
《Palaeoworld》2022,31(4):600-606
Anabaritids are a group of tubular skeletal fossils known from the lower Cambrian worldwide. Many previously collected specimens of anabaritids lack both the apical and apertural regions, and thus their complete morphology and growth patterns are not fully understood. Here we describe a number of internal molds of Anabarites from the lower Cambrian (Fortunian Stage) Zhangjiagou Lagerstätte, southern Shaanxi Province. Our new specimens preserved the apex, the aperture with three lobes, and three longitudinal grooves initiating apically rather than adapically as previously reported. This work enriches the morphology of anabaritids, casting doubt on the previous proposition that anabaritids originated from a cylindrical tubular ancestor. It is proposed here that a triradial symmetry may have been established in very early ontogenetic stages of some anabaritids; furthermore, the aperture with three lobes resembles those of olivooids and thus supports a possible close relationship between anabaritids and olivooid scyphozoans. 相似文献
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《Palaeoworld》2023,32(1):14-26
Dabashanellids are univalved phosphatocopid crustaceans, and are among the earliest crustaceans known so far. They were reported mainly from the Cambrian Stage 3 of China, but only a single species was established. Here I report a new assemblage of dabashanellids from the Cambrian Stage 3 Shuijingtuo Formation in western Hubei Province, South China. All specimens are sub-millimetre in length, and are preserved as three-dimensional carbonaceous hollow shields. Five species of Dabashanella were recognized, including the previously reported D. hemicyclica, three new species, D. longa n. sp., D. semiorbiculata n. sp., D. unispinata n. sp., and an indeterminate form Dabashanella sp. In addition, five indeterminate forms of arthropods were recovered. These dabashanellids represent part of a meiofauna that lived in the off-shore, deeper environments of mid-northern Yangtze Sea during Cambrian Age 3. This study shows greater morphological diversity and ecologic disparity of dabashanellid crustaceans, and supports the previous suggestion that the invasion of meiofaunal ecdysozoans into the off-shore, deeper environments probably occurred simultaneously with their radiation in the shallow water. 相似文献
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对滇东会泽雨碌、寻甸摆宰早寒武世梅树村期软舌螺壳质微细结构的研究表明,软舌螺壳的孔沟系统十分发育,壳的外层由分叉与合并呈纵向排列的长纤束组成,内层由横向分布的粒柬组成。在外层纤柬之间和纤柬内分布有大量的三角形或长椭圆形的孔洞,这些孔洞的长轴平行于壳的生长方向;在内层粒束之间或粒柬内有横向分布的长沟。内外层的沟孔可以相通。在一些软舌螺纵向和横向的切片中,均发现早期磷酸岩化作用中已被磷质颗粒充填的孔沟形态,这些孔沟分布相当密集,基本垂直壳面,几乎通达壳壁的顶底。多孔性的壳既反映了软舌螺对其特殊的生理和生态功能的要求,也反映了早期带壳动物的原始性和它们在早期生物矿化作用中的特殊地位。 相似文献
15.
三叶虫是古生代海洋中最引人注目的节肢动物之一, 其外骨骼具有极高的多样性。相较于易于保存的矿化外骨骼, 三叶虫的软躯体构造往往难以在化石记录中保存, 这增加了三叶虫内部构造解剖和演化的研究难度。寒武纪布尔吉斯页岩型特异埋藏化石群中独特的保存条件使得三叶虫精细的软躯体构造得以保存, 为解析三叶虫内部构造提供了材料。本文描述了来自云南昆明呈贡下庄剖面寒武系第二统第三阶红井哨组泥岩中产出的云南马龙头虫(Malongocephalus yunnanensis Zhang and Lin in Zhang et al., 1980)的软躯体构造。标本展示了M. yunnanensis的触角至少有13个肢节, 触角后附肢具有板片状的外肢。消化道分化为前肠、中肠和后肠, 头部见三对消化腺。这是莱德利基虫目(Redlichiida)小阿贝得虫科(Abadiellidae)中软躯体构造的首次报道, 丰富了寒武纪早期三叶虫的解剖学信息。本研究比较分析了莱德利基虫目的触角相对长度差异, 对三叶虫的消化系统构造进行了讨论。 相似文献
16.
本文描述了陕西镇巴下寒武统水井沱组中的小壳化石3新属5新种。样品采自镇巴小洋坝曾家坡,共生化石有三叶虫、古介形虫、海绵骨针和大量软舌螺等。化石组合面貌表明其地质时代属筇竹寺期。另外,在峡东水井沱组中发现了微网虫(Microdictyonsp.)化石骨片(图版I,图18,19),可与云南筇竹寺组及陕南水井沱组对比,说明Microdictyon广泛分布于扬子地台区。 相似文献
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A new trilobite, Longaspis paiwuensis n. gen. n. sp., from the Balang Formation (Cambrian Stage 4) in northwestern Hunan, South China, is described. This rare trilobite adds to an expanding taxonomic list of organisms recognized from the Balang Lagerstätte, a deposit of exceptional preservation from the Cambrian. Longaspis paiwuensis is an unusually large-sized, micropygous oryctocephalid trilobite that has proparian facial sutures, pit-like lateral glabellar furrows, up to 17 thoracic segments, and a distinct medial notch in the pygidium; it lacks marginal spines.The classification of the family Oryctocephalidae is reviewed. Three subfamilies are recognized, and Longaspis n. gen. is assigned to the subfamily Oryctocarinae. 相似文献
18.
Abstract: The morphology and ontogeny of the eodiscid trilobite Tsunyidiscus acutus Sun is described on the basis of numerous calcified specimens collected from the Lower Cambrian Shuijingtuo Formation in Yichang and Changyang, Hubei Province, South China. An ontogenetic series is established based on the articulated material including the previously unknown protaspides and meraspides (degrees 0 and 1). The material, revealing some prominent morphological changes such as the number of pygidial axial rings, genal spines retained throughout ontogeny and pygidial pleurae from furrowed to unfurrowed, enables a discussion on the trunk segmentation schedule, indicating that somitogenesis and tagmosis occurred independently during the ontogenetic development of T. acutus. 相似文献
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《微体古生物学报》2015,(4)
本文对采自陕西洛南上湾剖面下寒武统辛集组疑难管状化石Cupitheca进行了研究,系统厘定和描述了两个种,分别为Cupitheca holocyclata和Cupitheca costellata,并对Cupithecidae科进行了重新修订。本文所描述标本的壳体多为次生磷酸盐化保存,壳体表面纹饰保存较好;C.holocyclata管体表面为横向纹饰,C.costellata管体表面为纵向纹饰。C.holocyclata全球广布,如南澳大利亚、南极乔治王岛、格陵兰东北部、加拿大纽芬兰等地皆有报道,产出于下寒武统中上部地层,具有一定的洲际地层对比意义。本文为C.holocyclata在中国首次发现。C.costellata仅发现于华北,即本文所研究的洛南辛集组及其同期地层安徽淮南与霍邱的雨台山组。 相似文献