Precambrian phosphatized embryos and larvae from the Doushantuo Formation and their affinities, Guizhou （SW China）

Weng＇an phosphates of the Precambrian Doushantuo Formation, Guizhou （southwestern China） preserve a large number of exquisite biological structures, which are mostly micro-spherical and represent seaweeds, acritarchs and developing eggs related to various groups of metazoans. Here is a report of a variety of developing eggs and larvae, which are most probably of Cnidarian affinity. The eggs examined in the study are composed of early cleavage embryos and two-layered gastrulae. The early cleavage embryos are radial and total cleavage with equal-size blastomeres. The gastrulae mostly bear a large archenteron, which is filled with yolk-degrading organic matter. Ovoid to fusiform planula-like larvae identified in thin sections under light microscope are mostly mouthless and their gastrovascular cavity is filled with possible yolk-degrading organic matter. They are likely representatives of non-feeding larva. The uncommon planula-like structures are hollow, with each having a mouth-like structure on its narrow end. We interpret them as feeding larva. Study of these embryos with possible Cnidarian affinities shed new insight on the origin of metazoans.     

Discovery of a Miaohe-type Biota from the Neoproterozoic Doushantuo Formation in Jiangkou County, Guizhou Province, China

A megascopic algal fossil assemblage was first discovered by Ma Guogan and Chen Meng‘e in the black shales of the Neoproterozoic Doushantuo Formation in Miaohe Town, Zigui County, Hubei Province in 1978. Formal naming of the Miaohe Biota was proposed by Cheng Meng‘e and Xiao Zongzheng in 199112j, and eleven morphological genera have been previously described. including megascopic algae and putative metazoans .Ding et al. greatly expanded the scope of the Miaohe Biota to 9 phyla consisting of 140 genera, including microphytoplanctons, megascopic algae, metazoans, spongesand trace fossils. Xiao et al. further restudied this fossil assemblage, concluding that only about 18 distinct taxa could be recognized and that many Miaohe taxa are poorly defined or svnonvmous.     

A detailed Lower Triassic conodont biostratigraphy and its implications for the GSSP candidate of the Induan–Olenekian boundary in Chaohu, Anhui Province

Chaohu is located in a deep part of carbonate ramp on the Lower Yangtze Block, which belonged to the low-latitude eastern Tethyan archipelago during the Early Triassic. Fossils were very rich in the Lower Triassic of Chaohu. Bivalves, ammonoids, conodonts were very common throughout the Lower Triassic, while fish fossils were generally rich in some beds of the upper part. It is one of the most typical sections for the Early Triassic chronostratigraphy in the world. Although various fossils had been studied in the 1980s and 1990s, recent studies based upon new and more detailed collections from the Lower Triassic of Chaohu showed that the conodont zonation needs revision. We collected Lower Triassic conodont fossils from continuous sections of the West Pingdingshan, North Pingdingshan and South Majiashan, Chaohu, Anhui Province, and updated zonations were made for each section. Eight conodont zones have been distinguished. They are, in ascending order, Hindeodus typicalis zone, Neogondolella krystyni zone, Neospathodus kummeli zone, Neospathodus dieneri zone, Neospathodus waageni zone, Neospathodus pingdingshanensis zone, Neospathodus homeri zone, and Neospathodus anhuinensis zone. The first occurrence of Neospathodus waageni eowaageni of the N. w. eowaageni subzone （i.e. the base of the N. waageni zone） is suggested as the marker to define the Induan-Olenekian boundary.     

Original component of grain size index in core sediment from southwestern slope of the South China Sea and its paleoenvironmental implication

Traditional grain size analysis was basically used to discriminate sediment type based on its particle dimension for sedimentary naming[1,2] and to analyze the dynamic feature of transport medium, including water current and wind strength[3―5]. Recently, some patency advances havebeen made by using different methods to separate different grain sizes in various original composition from sediments for searching a new way of paleoenvironmental study[6―8]. Grain size analysis is even playing an …     

New fossil elaterids （Insect： Coleoptera： Polyphaga： Elateridae） from the Middle Jurassic of Inner Mongolia, China

A new genus with a new species of fossil elaterid, Paraprotagrypnus superbus gen. et sp. nov., from the Middle Jurassic Jiulongshan Formation in Daohugou Village (N41°18.979′, E119°14.318′), Shantou Township, Ningcheng County, Inner Mongolia, China is described and illustrated. The genus Paraprotagrypnus belongs to the family of Elateridae, subfamily of Protagrypninae and tribe of Protagrypnini. Some primitive characters of the new genus and new species shed light on the ages between the Jiulongshan Formation in Inner Mongolia and the Yixian Formation in the western Liaoning Province of China. The habitat of the new species is briefly discussed.     

Affinities and functional morphology of the Middle Cambrian ornamented tubules from West Hunan, China

Problematic phosphatic tubular microfossils with ornamented sculptures are documented to exist in limestones of the upper Middle Cambrian Huaqiao Formation at the Paibi section and the Wangcun section in West Hunan, China. Two morphological patterns, including Ornamented Tube Form I and Ornamented Tube Form II are described. Based on the analysis of the preservation, wall structure and composition of the fossils, it is deduced that these ornamented tubes may represent carapace spines of some Cambrian arthropods with phosphatic carapaces, such as bradoriid crustaceans. Analysis of functional morphology indicates that the sclerites may rather be considered of a defensive than grasping function on the original organism body.     

New dragonflies （Insecta： Odonata： Gomphaeschnidae） from the Yixian Formation in Inner Mongolia,China

Two fossil dragonflies from the Upper Jurassic to Lower Cretaceous Yixian Formation in Liutiaogou Village, Ningcheng County, Inner Mongolia, China are described and illustrated. They are assigned to two new genera and species, i.e., Sophoaeschna frigida gen. et sp. nov. and Falsisophoaeschna generalis gen. et sp. nov. within the family Gomphaeschnidae Tillyard ＆ Fraser, 1940. This is the first report of Odonata from Yixian Formation in Inner Mongolia and the second record of fossil Gomphaeschnidae from China.     

Microbial control of diamondback moth, Plutella xylostella L. （Lepidoptera： Yponomeutidae） using bacteria （Xenorhabdus nematophila） and its metabolites from the entomopathogenic nematode Steinernema carpocapsae

Cells and cell-free solutions of the culture filtrate of the bacterial symbiont, Xenorhabdus nematophila taken from the entomopathogenic nematode Steinernema carpocapsae in aqueous broth suspensions were lethal to larvae of the diamondback moth Plutella xylostella. Their application on leaves of Chinese cabbage indicated that the cells can penetrate into the insects in the absence of the nematode vector. Cell-free solutions containing metabolites were also proved as effective as bacterial cells suspension. The application of aqueous suspensions of cells of X.nematophila or solutions containing its toxic metabolites to the leaves represents a possible new strategy for controlling insect pests on foliage.     

A new fossil genus of Mesosciophilidae （Diptera, Nematocera） with two new species from the Middle Jurassic of Inner Mongolia, China

A new genus within the family Mesosciophilidae,Jurasciophila gen.nov.,with two new species,J.curvula gen.et sp.nov.and J.lepida gen.et sp.nov.,are described and illustrated.They are established based on fossil specimens with bodies and complete wings.All of them were collected from the late Middle Jurassic Jiulongshan Formation of Daohugou in southeastern Inner Mongolia,China.Comparing with two known genera,Mesosciophilina (Kovalev,1985) and Mesosciophilopsis (Blagoderov,1994),the new genus has transitional characters.The distribution pattern of Mesosciophilidae is briefly discussed.     

贵州中三叠世盘县动物群比耶鱼属未定种的发现及其意义

记述采集自贵州省盘县中三叠统安尼阶关岭组上段盘县动物群的一件仅残存尾部的比耶鱼标本。这是比耶鱼在该动物群的首次报道, 也是目前比耶鱼在中国地质时代最早的化石记录。依据标本个体大、仅尾上叶及尾柄后缘背侧覆盖有狭长条状且缺失硬鳞质的鳞片、尾部发育单个愈合的神经棘和脉棘、尾鳍背缘棘鳞发育等特征, 将其归入比耶鱼属。同时, 该标本以个体更大(推测身长超过2 m)、尾下骨更多(9 根)、尾下叶棘鳞发育以及上、下叶外缘交角超过 70°等特征, 不同于已报道的其他比耶鱼物种。但是, 考虑到标本信息有限, 暂定为比耶鱼未定种Birgeria sp.。比耶鱼是仅见于三叠纪海洋中的全球性分布的大型肉食鱼类, 其在盘县动物群中的首次发现丰富了该动物群鱼类多样性, 增加了其群落生态结构的复杂性。基于当前化石发现的情况, 认为比耶鱼在东特提斯生物区(中国)较西特提斯生物区的出现可能更晚, 前者最早的化石记录见于中三叠世安尼期, 而后者最早见于早三叠世史密斯亚期。     

贵州省盘县中三叠世羊圈幻龙新材料的研究

详细描述产自贵州省盘县新民乡羊圈村中三叠统关岭组上段的一件近于完整的羊圈幻龙新标本,并补充完善该种头后骨骼学信息。厘定后的羊圈幻龙的鉴定特征为:4个前颌骨獠齿后面跟着一个小的前颌骨齿;5~6个小的上颌骨齿后面跟着一对上颌骨獠齿;腕骨4块;间锁骨没有后突;荐椎4块;存在多指(趾)式。新标本的头后骨骼首次呈现一些原认为仅出现在幻龙属姊妹群——鸥龙属的一些特征,如间锁骨没有后突,腕骨4块,荐椎4块及存在多指(趾)式。这些特征的发现为深入认识和区分幻龙属和鸥龙属之间性状的异同提供了重要的信息。另外,新标本与羊圈幻龙模式标本,以及相同地点、相同地层层位产出的小吻幻龙模式标本IVPP V 14294在体型、齿式和头骨骨骼模式等高度一致,且与幻龙属其他种明显不同,因此认为它们系同物异名。鉴于N.rostellatus后出,应予弃用。     

贵州中三叠世盘县动物群产出地层的稀土元素特征及其地质意义

对产出盘县动物群化石的贵州羊件剖面岩石样品中稀土元素含量(质量分数)变化规律进行了研究,结果表明：剖面大部分沉积时间是处于弱还原的沉积环境;样品中稀土元素含量的异常波动主要受当时的火山作用影响,其沉积物物源有2大类4亚类,分别来自拉斑玄武岩和沉积岩;沉积岩样品的轻稀土、中稀土、重稀土配分极为相似,表现为稳定的演化特征,指示出当时剖面所处位置的构造环境较为稳定。     

贵州兴义中三叠世黔鱼龙属(爬行纲: 鱼龙目)一新种

A new species of Qianichthyosaurus Li, 1999 from the Zhuganpo Member of the Falang Formation (Ladinian, Middle Triassic), Wusha Town, Xingyi City of Guizhou is described here, namely Qianichthyosaurus xingyiensis sp. nov. The recognition of the new species revises the diagnosis of the genus: tooth size relative to the skull width slightly below 0.1; ulna peripheral “shaft” notched or largely reduced; hindlimb nearly equal or longer than forelimb; tibia peripheral “shaft” notched or largely reduced. Qianichthyosaurus xingyiensis sp. nov. differs from the type species in having relatively longer snout (snout length/skull length over 60%); humerus radial facet being prominently larger than ulnar facet; unenclosed obturator foramen on pubis; fibula posterior process on the posterior margin and the ischium sub-triangular lacking shaft. The new species is stratigraphically older than Q. zhoui, the specimens of which were exclusively known from the Wayao Member of the Falang Formation (Carnian, Late Triassic). Along with askeptosaurid thalattosaur Anshunsaurus and shastasaurid ichthyosaur Guizhouich- thyosaurus, the occurrence of Q. xingyiensis sp. nov. in Xingyi Fauna suggests a closer relationship between Xingyi Fauna (late Ladinian, Middle Triassic) and Guanling Biota (Carnian, Late Triassic).     

盘县动物群研究进展

盘县动物群是以保存完整、精美、属种丰富的海生爬行动物化石为特色,伴生海生 无脊椎动物化石的一套完整的珍稀古生物群落。盘县动物群产于中三叠统关岭组上段,属于 牙形石Nicoraella kockeli带,时代为中三叠世安尼期的Pelsonian亚期,早于著名的 意大利—瑞士交界处Monte San Giorgio地区的Grenzbitumenzone动物群（安尼阶—拉丁阶界线 附近）,是目前世界上中三叠世最老的海生爬行类动物群。它的发现和研究填补了海生爬行动 物演化的早期链条,增强了人们对海生爬行动物各类群的起源、演化、系统发育、古生物地 理以及动物群特异埋藏理论的认识。近期研究表明,盘县动物群中的海生爬行动物：（1） 具有较高的分异度,已报道5属5种,拥有了目前发现的最古老的混鱼龙科分子、鸥龙属分子、 较老的幻龙属分子和真正适应水生生活的原龙类以及诸多未描述的类群;（2） 动物群多由 适应近岸浅水环境的类群组成,在面貌上呈现出强烈的西特提斯生物亲近性;（3） 动物群属 特异埋藏,赋存层分布有4～5层凝灰岩,化学特征分析显示存在7次火山间歇性喷发活动,火 山活动导致的生态环境急剧恶化可能是动物群集群绝灭的直接诱因。     

Sauropterygian from Triassic of Guizhou, China

A new sauropterygian,Anshunsaurus huangguoshuensis, is described on the basis of a well-preserved skull from the Late Triassic Wayao Member of Falang Formation, Guizhou Province, southwestern China. It is ascribed to Eusauroptetrygia because it possesses the following characters: the rostrum is mainly composed by the premaxillae; the nasals are small, paired and separated from one another by the premaxillae; the external nares are close to the orbits; and the frontals are fused.Anshunsaurus differs from other Triassic sauropterygians in its large size, long rostrum and the supratemporal fenestrae slightly smaller than orbits. It is further considered to be closely related toPistosaurus on the basis of the nasals contact with the prefrontals; large pineal foramen, lain in the anterior part of the parietal table; the squamosals not in contact posterior to the supratemporal fenestra. The discovery ofAnshunsaurus with the ichthyosaurs in the same locality indicates a new assemblage of Triassic marine tetrapods in China.     

A new cyamodontoid placodont from Triassic of Guizhou, China

A new cyamodontoid placodont is named (Psephochelys polyosteoderma gen. et. sp. nov.) and described based on a three-dimensionally preserved specimen. The material comes from the Wayao Member of the Falang Formation (Carnian, Late Triassic) in Guizhou Province, southwestern China. The skull of Psephochelys shows a unique combination of characteristics observed in Psephoderma and Placochelys, and the carapace is diagnostic of a new taxon as well. The ventral dermal armor of Psephochelys differs from all other known cyamodontoids in that it comprises irregular marginal osteoderms in loose contact with each other, and gastralia between them. The cranial suture pattern is in part difficult to analyze due to apparent co-ossification of elements, or poor delimitation of sutures.This affects primarily the demarcation of the nasal from the prefrontal, and the relation between the anterior part of the parietal, posterior ends of the frontals, and postfrontals.However, the postfrontal appears to enter the anteromedial margin of the upper temporal fenestra, a characteristic otherwise known from Placodus, but not from other cyamodontoids. However, given the difficulties of interpretation of this skull, additional material is required to unequivocally assess some details of the pattern of cranial sutures.     

贵州关岭晚三叠世邓氏贵州鱼龙（Guizhouichthyosaurus tangae Cao and Luo in Yin et al., 2000）的讨论

贵州省关岭县新铺地区晚三叠世法郎组瓦窑段下部的鱼龙标本保存完整、精美,对它们准确而详细的描述将对研究鱼龙类分类、演化和完善其演化谱系具有重要的意义。目前对其中大型鱼龙已有Guizhouichthyosaurus tangae、Typicusichthyosaurus tsaihuae、Guanlingsaurus liangae、Cymbospondylus asiaticus、Panjiangsaurus epicharis等5个命名。在野外调查、室内修理、观察、比较的基础上,补充、修正了Guizhouichthyosaurus tangae的描述,并认为Cymbospondylus asiaticus和Panjiangsaurus epicharis应为Guizhouichthyosaurus tangae的同物异名。     

贵州盘县晚二叠世煤的生烃潜力与生烃模式

用有机地球化学方法研究贵州中西部地区煤岩的生烃机理和生烃模式。石英小玻管热模拟实验和红外光谱对贵州盘县晚二叠世煤的分析表明, 盘县煤的干酪根类型为Ⅲ型, 主要成分是均质镜质体和丝质半丝质体, 主要生成物是短链烃, 显著生烃的起始温度约为300 ～350 ℃。     

贵州关岭晚三叠世一海龙头骨的初步研究

对产自贵州省关岭县晚三叠世卡尼期瓦窑组的一件新铺龙头骨标本进行了详细的描述,并和新铺龙属另外两种的标本进行了对比,认为该标本以下特征与其他新铺龙类似：上下颌咬合时头骨侧视呈直角三角形;齿骨前部由于弯曲形成一个平台;前颌骨末端形成明显的凹缘;鼻骨向后延伸至离外鼻孔较远处;前颌骨内侧突向后延伸至外鼻孔之后。因此将其归入新铺龙属。但其与其他两种存在以下明显区别：成年个体明显较大;前颌骨末端的牙齿倒伏方向向后;前颌骨参与了外鼻孔的形成;没有翼骨齿;前额骨与鼻骨接触;齿骨后端和上颌骨没有牙齿。由于标本保存不完整,重要的颅区骨骼和头后骨骼特征无法鉴定,因此暂将其归入一未定种。