新疆首次发现的侏罗纪龟类

本文记述了新疆准噶尔盆地的一件龟化石,名为准噶尔新疆龟,新属、新种 (Xinjiangchelys junggarensis, Gen. et sp. nov.),其时代可能为中侏罗世.这是新疆地区侏罗纪龟类的首次记录.早、中侏罗世是龟类的早期进化阶段,国外材料甚少.文章在讨论了新疆龟的系统分类后,综述了我国早、中侏罗世的龟类记录,并结合泰国近年发现的晚三叠世的龟类,认为亚洲是迄今所知拥有龟鳖类进化各时期记录最完全的地区,是探索龟类起源和早期进化的重要地区之一.     

龟鳖类的早期进化

在1987年美国出版的《科学》杂志第273卷上,刊登了一篇题为《现代龟类的起源:已知最古老的隐颈龟》研究简报。文中记述了在美国亚利桑那州东北部卡那他层中发现的龟类化石,命名为密合卡那他龟(Ka-yentachelys aprix)。属名取自出产标本的地层名,种名则表示该龟的基颅关节紧密愈合。卡那他龟不仅生存的年代早(早侏罗世,距今一亿八千五百万年前),且具有许多两类现生龟——侧颈龟和隐颈龟臆想的共同祖先的原始特征,因而被认为与现生龟类的起源有关。自从南非中二叠世(距今二亿五千万年前)的正南龟(Eunotosaurus)被否定为龟类后,现知龟鳖类的最早代表是西德、泰国晚三叠世(距今二亿年前)的原颚     

安徽古新世的龟类

本文记述了安徽古新世龟科的一新属(安徽龟属)、两新种(小市安徽龟、潜山安徽龟)以及该属的一个未定种。古新世是龟科迄今确知的最早地史记录,目前报导尚不多。就整个龟鳖类来看,古新世的材料也是比较少的。连同本文记述的,我国已知古新世龟鳖类的记录共有2科、3属、5种。     

广东南雄新生代龟类化石

古脊椎动物与古人类研究所于1962—1963和1963—1964在广东南雄进行了两个季度野外调查工作,采集了许多脊椎动物化石,其中包括一批龟类标本。这批鱼类标本除一件产自白垩纪的大型龟类业已研究报导外(叶,1966),其它皆产自新生代。本文就是这些新生代龟类的记述。     

我国最早的龟类化石

1977年冬,我所董技明同志在四川进行脊椎动物化石调查时,于资中县铁佛公社狮子山采集到了几块龟类甲片。化石产自自流井群马鞍山段。关于自流井群的时代,目前尚有不同见解,但有两种意见比较集中:一认为是早侏罗世;另一认为是中侏罗世。自从否定了南非二迭纪的“正南龟”是龟鳖类以后,欧洲晚三迭世(?中三迭世)的原颚龟(或叫三迭龟)便成为龟鳖类的最早化石记录了。往后,在早、中侏罗世,材料非常贫乏,已知的只有欧洲少数1—2个属为代表,并有的尚有怀疑。而到了     

西藏蝽类昆虫新种记述(半翅目:异翅亚目)

本文记述我国西藏蝽类昆虫(半翅目异翅亚目)6个新种,分隶于4科3亚科5属。新种的模式标本,除部分副模由南开大学生物系保存外,均收藏在中国科学院西北高原生物研究所。 龟蝽科Plataspidae似镶边豆龟蝽Megacopta fimbrilla,新种(图1—3)     

河南舞阳县贾湖遗址中的龟鳖类

本文记述了贾湖遗址中的龟鳖类甲壳。主要为现生黄缘闭壳龟（Ｃｕｏｒａ ｆｌａｖｏｍａｒｇｉｎａｔａ）,背、腹甲完整者有５０多件。其它龟类和鳖类只有部分甲壳或碎片为代表。文中除属种鉴定外,还对甲壳上的个体变异和有关人类活动等问题作了探讨。     

山东莱阳白恶纪后期龟类化石

一.绪言本文记述的两种白垩纪龟类化石,是1951年前新生代及脊椎古生物研究室在山东莱阳采集的大批脊椎动物化石中的一部分,系刘东生与王存义两同志在莱阳的陡山及金刚口两处所发现。金刚口发现的仅一片肋甲;陡山的包括一异常完整的龟类甲壳与另一个体的一部分甲壳,前者为我国至目前为止所发现的中生代龟类化石中最完整的标本,在地层与地理分布上都有相当意义。     

古猿闭壳龟的新材料及该属的地史分布

云南禄丰古猿产地发现的古猿闭壳龟(Cuora pitheca Yeh,1981),是闭壳龟属的首次化石记录。它的发现,把该属的历史从现代一下追溯至中新世晚期。本文除补充记述古猿闭壳龟的新材料外,并结合近年国内外的新发现,综述了该属龟类的地史分布。     

龟鳖类锥虫两新种（动体目：锥体科）

龟鳖类锥虫的研究,国内外均比较少。本文记述了在中华鳖和乌龟血液中发现的两新种,鳖锥虫和龟锥虫。这是国内首次对龟鳖类锥虫研究的报道。     

四川中侏罗世的龟化石

本文对产自四川自贡中侏罗世的三件龟甲标本作了鉴定,认为均可归成渝龟属(Chengyuchelys)。一为自贡成渝龟,新种(Chengyuchelys zigongensis,sp.nov.),一为似贝氏成渝龟(C.baenoides, Young et Chow),一为成渝龟未定种(Chengyuchelys sp.)。在形态描述的基础上,讨论了成渝龟属的系统分类。     

四川自贡大山铺成渝龟科—新属

描述了产自四川自贡大山铺恐龙化石坑中的三件龟甲标本,命名为一新属新种—周氏四川龟（Sichuanchelyschowigen．etsp．nov．）。该属以椎盾极横宽,中部缘盾极狭长为主要特征,它代表了成渝龟科中一类较特别的类型。     

四川内江晚侏罗世中国龟科一新属

描述了产自四川内江晚侏罗世的中国龟科（Ｓｉｎｅｍｙｄｉｄａｅ）化石一新属新种──叶氏香港龟Ｈｏｎｇｋｏｎｇｏｃｈｅｌｙｓ ｙｅｈｉ。它以椎盾较横宽、第７、８椎板较退化、上臀板缺失、具腹甲后窗等特征区别于中国龟属（Ｓｉｎｅｍｙｓ）和满洲龟属（Ｍａｎｃｈｕｒｏｃｈｅｌｙｓ）。这是中国龟科化石在四川的首次发现．     

记甘肃晚侏罗世一蜥蜴新属

本文记述石龙子类 Scincomorpha 蜥蜴的—新属,甘肃拟贝氏蜥 Mimobefklesisaurus gansuensis gen. et sp. nov. 化石发现于甘肃省肃北县马宗山区晚侏罗世的赤金堡群.这是石龙子类化石在我国的第一次发现,也是目前所发现的这类动物在亚洲的最早的代表.     

A revision of xinjiangchelyid turtles from the Late Jurassic of Sichuan Basin,China

The type specimens of the Jurassic turtles from the Sichuan Basin (China) previously referred to plesiochelyid Plesiochelys are revised, which confirm that they belong to the family Xinjiangchelyidae. The study of a large number of additional shell material shows, as the dominant group, the Xinjiangchelyidae were greatly diversified in the Late Jurassic of the Sichuan Basin. By the absence of mesoplastron and other shell characters, Chengyuchelys baenoides is moved to Xinjiangchelyidae and considered as a valid taxon. Of the xinjiangchelyids from the Late Jurassic of Sichuan Basin, four genera are recognized: Chengyuchelys, Tienfuchelys, Yanduchelys and cf. Protoxinjiangchelys. The phylogenetic analysis results in that Chengyuchelys includes C. baenoides, C. latimarginalis and C. radiplicatus, and Tienfuchelys consists of T. tzuyangensis, T. chungkingensis and T. zigongensis. All xinjiangchelyids from the Sichuan Basin are more primitive than Xinjiangchelys in the plastron sutured to the carapace.     

A survey of the epibiota of Eretmochelys imbricata (Testudines: Cheloniidae) of Mona Island, Puerto Rico

Epibiotic organisms inhabiting non-nesting hawksbill sea turtles, Eretmochelys imbricata (Linnaeus, 1766), are described from Mona and Monito Islands, Puerto Rico. Epibiont samples from 105 turtles of shallow (< 40 m) water foraging habitats were collected and identified to the lowest possible taxon. This epibiotic assemblage consisting of at least 4 algal functional groups and 12 animal phyla represents the greatest phylogenetic diversity for marine turtle epibiota. Six groups are considered new reports for marine turtles. Most epibiont colonization was found on posterior marginal scutes and under overlapping scutes. Ecological attributes of epibiota and their symbiosis with E. imbricata provide a tool to understand basi and epibiont populations.     

A new, nearly complete stem turtle from the Jurassic of South America with implications for turtle evolution

Turtles have been known since the Upper Triassic (210Myr old); however, fossils recording the first steps of turtle evolution are scarce and often fragmentary. As a consequence, one of the main questions is whether living turtles (Testudines) originated during the Late Triassic (210Myr old) or during the Middle to Late Jurassic (ca 160Myr old). The discovery of the new fossil turtle, Condorchelys antiqua gen. et sp. nov. from the Middle to Upper Jurassic (ca 160-146Myr old) of South America (Patagonia, Argentina), presented here sheds new light on early turtle evolution. An updated cladistic analysis of turtles shows that C. antiqua and other fossil turtles are not crown turtles, but stem turtles. This cladistic analysis also shows that stem turtles were more diverse than previously thought, and that until the Middle to Upper Jurassic there were turtles without the modern jaw closure mechanism.     

Scute’s polymorphism as a source of evolutionary development of the turtle shell

The scute mosaic (pholidosis) of the turtle shell is a complex correlated system of the modular type. Horny scutes are separate morphological elements partially closely connected with each other and partially relatively autonomous in development. The last feature causes high variability of scutes in the shape, size, rate and direction of growth, and provides the basis of transformation of the entire mosaic. In the evolution of turtles, the horny shell changed towards a decrease in the number of elements composing it. The process of oligomerization developed through reduction and fusion of scutes or their anlages. The traces of these transformations are observed in the ontogeny of living turtles. The scutes undergoing reduction display the following developmental deviations: (1) a decrease in size of the scute anlage, (2) the temporal shift in initiation to later embryonic stages, (3) absence of an anlage of a own furrow (the boundaries of the scute are formed by the furrows of neighboring scutes), and (4) a decrease in size of the zone and rate of the scute growth. The fusion of horny scutes follows two patterns: (1) fusion of scute anlages and (2) reduction of horny furrows separating scutes before. Secondary polymerization of the scute mosaic by the appearance of additional elements usually results from abnormal development and is infrequently fixed in evolution. The main mechanism of evolutionary changes in turtle pholidosis was heterochrony, i.e., the time shift in initiation and developmental rate of scutes. The heterotopies, i.e., changes in the position of scute anlages, played a minor role in the evolution of turtles; they usually caused only scute abnormalities, which was frequently asymmetrical.