The Earliest Normal Flower from Liaoning Province, China

The early evolution of angiosperms has been a focus of intensive research for more than a century. The Yixian Formation in western Liaoning yields one of the earliest angiosperm macrofloras. Despite multitudes of angiosperm fossils uncovered, including Archaefructus and Sinocarpus , no bona fide normal flower has been dated to 125 Ma (mega-annum) or older. Here we report Callianthus dilae gen. et sp. nov. from the Yixian Formation (Early Cretaceous) in western Liaoning, China as the earliest normal flower known to date. The flower demonstrates a typical floral organization, including tepals, androecium, and gynoecium. The tepals are spatulate with parallel veins. The stamens have a slender filament, a globular anther, bristles at the anther apex, and in situ round-triangular pollen grains. The gynoecium is composed of two stylate carpels enclosed in a fleshy envelope, and develops into a "hip" when mature. Since the well-accepted history of angiosperms is not much longer than 125 Ma, Callianthus together with Chaoyangia, Archaefructus and Sinocarpus from the Yixian Formation demonstrate a surprisingly high diversity of angiosperms, implying a history of angiosperms much longer than currently accepted.     

Basal titanosauriform (Dinosauria, Sauropoda) teeth from the Lower Cretaceous Yixian Formation of Liaoning Province, China

The Yixian Formation of Liaoning Province, People's Republic of China has yielded a diverse fauna of non-avian dinosaurs, but is dominated by small-bodied taxa. Here, we describe a series of isolated teeth from the Lujiatun Beds of the formation that are referable to a basal titanosauriform sauropod. Some of the teeth possess a distinctive circular boss on the lingual surface, which suggests that they are referable to cf. Euhelopus sp. This identification provides some additional support for biostratigraphical correlations between the Jehol Group and the Mengyin Formation of Shandong Province that suggest an Early Cretaceous age for the latter unit. Moreover, the titanosauriform affinities of the teeth provide further evidence for the dominance of this sauropod clade in eastern Asia during the Cretaceous.     

辽宁西部早白垩世义县组一新的手盗龙类(英文)

我国辽西早白垩世热河群义县组和九佛堂组近年来产出大量恐龙化石 ,已知兽脚类恐龙包括 8属 1 0种 ,其中 6属 8种保存有原始羽毛或者羽毛结构。已经报道的属种均产自朝阳地区。 2 0 0 1年 ,中国科学院古脊椎动物与古人类研究所辽西野外考察队在邻近朝阳的锦州地区义县头台乡王家沟义县组下部采集到一件恐龙标本。这一标本保存了较为完整的肩带和前肢 ,在骨骼化石附近还保存了皮肤结构。通过研究对比 ,我们建立了手盗龙类的一个新属种 :长掌义县龙 (Yixianosauruslongimanusgen .etsp .nov .)。依据以下特征将长掌义县龙归入手盗龙类 :肩胛骨明显短于肱骨、肩臼窝的乌喙骨部分小、乌喙骨近四方形、尺骨向后弯曲以及挠骨细。长掌义县龙手部的相对长度以及手指各指节的相对比例不同于已知手盗龙类。原始兽脚类恐龙的手部一般短于肱骨 ;手盗龙手部加长 ,长于肱骨 ;原始鸟类的手部相对更长 ,但进步鸟类出现反转 ,手部次生变短。长掌义县龙手部的相对长度在非鸟兽脚类恐龙当中仅比原始祖鸟 (Protarchaeopteryx) (Jietal.,1 998)和树息龙 (Epidendrosaurus) (Zhangetal.,2 0 0 2 )短。次末端指节加长是兽脚类恐龙的一个进步特征 ,长掌义县龙具有这一特征。比如 ,长掌义县龙的手指指节Ⅱ 2长于掌骨Ⅱ ,在已知兽?     

辽宁早白垩世义县组一新的三尖齿兽类

描述了戈壁锥齿兽科 (Gobiconodontidae)一个新的属种———陆家屯弥曼齿兽 (Meeman nodonlujiatunensisgen .etsp .nov.)。标本产于辽宁西部朝阳市上园镇陆家屯下白垩统义县组一段的凝灰质砂岩层中 ,为一具完整齿列的左下颌骨。新属与戈壁锥齿兽 (Gobiconodon)共有以下区别于其他三尖齿兽类的特征 :2颗下门齿 ,i1增大 ,后部门齿、犬齿和前部前臼齿尖锥形 ,前臼齿具有高的中央尖和小的附尖 ,i～p1向前平伏。因此 ,新属被归入戈壁锥齿兽科。弥曼齿兽与戈壁锥齿兽及其相近属的区别在于 :下门齿和下犬齿更加平伏 ,i1在比例上更大 ,而i2则更小 ;最后一枚下前臼齿与第一枚下臼齿之间没有齿隙 ;前臼齿退化 ;下臼齿长度大于高度 ,主尖向后倾斜 ,与b尖和c尖相比 ,a尖较低 ,m1显著小于m2～ 4。新属下臼齿没有齿带 ,与爬兽 (Repenomamus)相似 ,而与戈壁锥齿兽不同。基于与爬兽齿列的对比 ,讨论了戈壁锥齿兽类的齿式 ,认为其应具有两颗门齿 ,而不是以前认为的 1颗门齿 ,从而将戈壁锥齿兽类下齿列齿式修订为 :2·1·2～ 3·5。     

辽宁中华弓鳍鱼(Sinamia)一新种

记述了辽宁西部九佛堂组和义县组中华弓鳍鱼一新种:辽宁中华弓鳍鱼Sinamia liaoningensis,并与该属的其他种进行了比较.新材料具有中华弓鳍鱼科的3个定义特征:单一的顶骨,三对额外肩胛骨和膜质翼耳骨短并与顶骨等长,无疑应归入该科.新种的后眶下骨较小,背鳍长大,鳞片菱形,因此,归入中华弓鳍鱼属.辽宁中华弓鳍鱼在以下几个方面不同于中华弓鳍鱼的5个已知种:体型短粗,吻骨较短,鼻骨近四方形,围眶骨较多(6),前鳃盖骨强烈弯曲,背鳍条较少(18),尾鳍条较多(16),臀鳍鳍基起点到鱼体背缘的鳞列较多(32),鳞片后缘不具锯齿,尾鳍具有纤维状的角质鳍条.     

辽宁西部早白垩世义县组一新驰龙类

我国辽西早白垩世义县组底部陆家屯层近年来产出大量恐龙和其他脊椎动物化石 ,其中包括兽脚类恐龙当中的伤齿龙类和窃蛋龙类 (Xu ,2 0 0 2 )。本文报道该层位产出的一件驰龙类化石标本。通过对比研究 ,我们确认这一标本不同于热河群已知的其他 3种驰龙类 ,并建立了驰龙类的一个新属种 :陆家屯纤细盗龙 (Graciliraptorlujiatunensisgen .etsp .nov .)。驰龙类最初发现于北美晚白垩世地层中 (MatthewandBrown ,1 92 2 ) ,随后在蒙古晚白垩世地层中也有发现 (Osborn ,1 92 4 ) ;现在已知驰龙类的化石记录主要集中在北美和中亚地区的白垩纪地层中 (Xu ,2 0 0 2 )。千禧中国鸟龙 (Sinornithosaurusmillenii)曾代表最早的确定无疑的驰龙属种 (Xuetal.,1 999) ,其生存时代大约为 1 2 5Ma (Swisheretal.,1 999)。陆家屯纤细盗龙正型标本产于义县组底部陆家屯层 ,其上覆和下伏岩层的同位素年代分别为 1 2 8Ma和 1 39Ma (Swisheretal.,2 0 0 1 )。因此 ,陆家屯纤细盗龙代表已知最早的驰龙属种。陆家屯纤细盗龙和其他驰龙类共享以下近裔特征 :尾椎前关节突和脉弧极度加长、上颌齿后缘锯齿明显大于前缘锯齿和指节III- 2明显缩短。陆家屯纤细盗龙的以下近裔特征区别于其他驰龙类 :中部尾椎有一板状结构连接左右后关节     

张氏格格翼龙(Gegepterus changae)新材料及其重要骨骼特征的补充和修订(英文)

张氏格格翼龙正型标本(IVPPV 11981)是产自辽西北票四合屯义县组下部的一件保存不完整的梳颌翼龙类化石材料。本文记述的新材料IVPP V 11972与正型标本产出于同一地点的相同层位,具有正型标本的3个独有特征,即泪骨前突位于鼻骨之上,额骨前部和侧部边缘处有广泛蚀痕以及颈椎具有高的神经脊且背部有瘤状膨胀,据此将其归入张氏格格翼龙。通过对新材料V 11972和进一步修理的正型标本的形态观察,对张氏格格翼龙的特征进行了补充,增加一个属征:鼻骨背腹向具有两个小孔。这一特征在正型标本中同样被观察到,但在其他翼龙中都没有出现,仅在飞龙中观察到一个孔和一个凹陷。同时补充了张氏格格翼龙的椎体和肩带等的一些特征,如背椎没有完全愈合,荐椎数量为3～4枚,尾椎约9枚;肱骨三角嵴不是十分发育,三角嵴颈及其与肩胛乌喙骨相关联的关节窝不发育;具有前端呈扇形的前耻骨,耻骨闭孔有小骨片覆盖等。依据格格翼龙新的特征,将其与我国发现的归于梳颌翼龙科(Ctenochasmatidae)的华夏翼龙(Cathaypterus)、环河翼龙(Huanhepterus)及鸢翼龙(Elanodactylus)进行了对比。依据齿槽处的纵向沟、牙齿分布密度以及吻端的长度比例等,认为格格翼龙和华夏翼龙有一定区别,但亲缘关系较近,同属梳颌翼龙亚科(Ctenochasmaniae),并建议将华夏翼龙的鼻眶前孔较小的属征修订为其吻端较长。格格翼龙的个体远小于环河翼龙,依据牙齿数量和排列的差异推测它们的捕食方式和食物类型存在明显的区别,应不属于同一亚科。新材料与鸢翼龙的明显区别主要在肱骨上,前者肱骨的肩胛骨关节窝不发育,而后者的这一结构明显。由于鸢翼龙没有保存头骨,它的分类位置不是十分确定,同时鸢翼龙具有许多梳颌翼龙类所不具有的特征,如第一翼指骨短于第二和第三翼指骨,掌骨较短等。     

Plants of Leptostrobus Heer （Czekanowskiales） from the Early Cretaceous and Late Triassic of China, with Discussion of the Genus

Investigation of the Mesozoic seed plant Leptostrobus Heer from the Yangcaogou Formation of the Late Triassic and the Yixian Formation of the Early Cretaceous, Liaoning Province, China, provides new Insight Into Its general morphology and geographical distribution. The materials of L. cancer from the Yixian Formation described herein are later than all the past findings of this species and add to the record of L. cancer during the Early Cretaceous. Based on well-preserved specimens, the specific diagnosis Is slightly emended and the reconstructlon of L. cancer Is perfected. The materials from the Yangcaogou Formation of the Late Triassic are placed in L. spheericus, in addition, we review the history of investigation of the genus Leptostrobus since its establishment in 1876 and discuss the main characteristics of each species.     

辽宁下白垩统九佛堂组伊克昭龙一新种

伊克昭龙 (Ikechosaurus)是一类长吻的离龙类 ,以前根据内蒙古的材料建立了孙氏种 (I.sunailinaeSigogneau Russell,1 981 )及高氏种 (I.gaoiL櫣ｅｔａｌ.,1 999)。根据蒙古的材料建立的TchoiriamagnusEfimov ,1 979也于 1 983年被原作者归入本属。本文记述了辽宁义县皮家沟九佛堂组新发现的一个近于完整保存的骨架 (中国科学院古脊椎动物与古人类研究所标本编号 :IVPPV 1 32 83) ,并建立一新种 :皮家沟伊克昭龙 (Ikechosauruspijiagouensissp .nov .)。新种以下列特征区别于伊克昭龙其他种 :轭骨前伸约至泪骨之半 ;眶间距小于眼眶短径 ;眶后骨与后额骨不愈合 ;髂骨片前突不发育 ,颈区不收缩 ;四肢中桡胫骨与肱股骨之比相对较小。另外其荐前椎数目与孙氏种相同 ,为 2 5枚 ,比鳄龙属 (Champsosaurus)少 1枚 ;坐骨明显比孙氏种短 ;桡肱骨长度之比为 0 .5 8,胫股骨长度之比为 0 .60 ,在所知新离龙类 (Neochoristodera)中属最小 ;前肢腕骨至少 7块 ,后肢跗骨至少 6块 ;指 /趾式均为 2 3 4 4 3。在正型标本中其第二远侧跗骨在左右脚中不对称。提出眶后骨与后额骨的愈合与分离以及轭骨眶后支发育程度不能作为Simoedosaridae和鳄龙科间的鉴别特征 ;股骨内转子与股骨头分离不该作为高氏种的鉴定特征 ;新离龙类?     

A perfect flower from the Jurassic of China

Flower, enclosed ovule and tetrasporangiate anther are three major characters distinguishing angiosperms from other seed plants. Morphologically, typical flowers are characterised by an organisation with gynoecium and androecium surrounded by corolla and calyx. Theoretically, flowers are derived from their counterparts in ancient ancestral gymnosperms. However, as for when, how and from which groups, there is no consensus among botanists yet. Although angiosperm-like pollen and angiosperms have been claimed in the Triassic and Jurassic, typical flowers with the aforesaid three key characters are still missing in the pre-Cretaceous age, making many interpretations of flower evolution tentative. Thus searching for flower in the pre-Cretaceous has been a tantalising task for palaeobotanists for a long time. Here, we report a typical flower, Euanthus paniigen. et sp. nov., from the Middle–Late Jurassic of Liaoning, China. Euanthus has sepals, petals, androecium with tetrasporangiate dithecate anthers and gynoecium with enclosed ovules, organised just like in perfect flowers of extant angiosperms. The discovery of Euanthus implies that typical angiosperm flowers have already been in place in the Jurassic, and provides a new insight unavailable otherwise for the evolution of flowers.     

Cranial morphology of an Early Cretaceous Monjurosuchid (Reptilia: Diapsida) from Liaoning Province of China and evolution of the choristoderan palate

A new specimen of Philydrosaurus proseilus from the Early Cretaceous Chiufotang (Jiufotang) Formation preserves the first complete palate of a monjurosuchid choristodere. As in other choristoderes, the palate of Philydrosaurus is akinetic, extended by a broad contact between the vomer and maxilla, and equipped with multiple batteries of palatal teeth. This specimen provides phylogenetically significant information and clarifies the distribution of many apomorphies within Choristodera. Philydrosaurus is primitive relative to the Neochoristodera in that it exhibits only a moderate degree of posterior displacement of the choanae and retains a relatively large interpterygoid vacuity. However, Philydrosaurus also exhibits several derived features previously considered diagnostic of the Neochoristodera, including establishment of a long midline contact of the pterygoids and development of a distinct nasopalatal trough extending from the choana. The choristodere palate exhibits significant modification of the primitive diapsid condition, including elongation of the vomers, establishment of a vomer–maxilla contact, posterior displacement of the choanae, development of the nasopalatal trough, and reduction of the interpterygoid vacuity.     

New material of Xyelydidae (Hymenoptera) from the Lower Cretaceous Yixian Formation of China

Chifengilyda robusta, a new extinct sawfly genus and new species assigned to Xyelidae, is described and figured here based on one fossil specimen from the Lower Cretaceous Yixian Formation of Ningcheng in Inner Mongolia, China. Chifengilyda robusta n. gen. n. sp. differs from other xyelydids in having a forewing with pterostigma completely sclerotized, Sc closer to C, Sc1 about 3 times as long as Sc2, Sc1 intersecting C far beyond Rs base, 2r-m postfurcal and cell 1mcu relatively large. This new taxon further enriches the diversity of Xyelydidae in the Early Cretaceous, and even enhances our understanding of the evolution and inter-genera and interspecies relationships of this family.     

A new choristodere (Reptilia: Diapsida) from the Lower Cretaceous of western Liaoning Province, China, and phylogenetic relationships of Monjurosuchidae

The publication of the scientific name Monjurosuchus splendens in 1940 documented the first tetrapod fossil of the later world-renowned Jehol Biota. For more than half a century since this discovery, however, Monjurosuchus has remained as a monotypic genus of the family Monjurosuchidae, and the relationships of the family with choristoderes have not been correctly recognized until quite recently. In this paper, a new monjurosuchid is named and described based on a nearly complete skull and postcranial skeleton from the Early Cretaceous Chiufotang Formation exposed near Chaoyang, western Liaoning Province, China. This new material documents the first occurrence of monjurosuchid choristoderes outside the type Lingyuan area, and extends the geological range of the family from the Yixian Formation to the younger Chiufotang Formation. Cladistic analyses were conducted with inclusion of monjurosuchids, and the results support the placement of the family Monjurosuchidae as a primitive clade outside the Neochoristodera. A new classification scheme is proposed for choristoderes on the basis of the recovered phylogenetic framework of the group.  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 145 , 427–444.     

A New Genus (Protosciadopityoxylon gen. nov.) of Early Cretaceous Fossil Wood from Liaoning,China

A new genus ( Protosciadopityoxylon gen nov. ) of Early Cretaceous fossil wood reported in the present paper was discovered from Liaoning Province, China, and is named as a new species:Protosciadopityoxylon liaoningense gen. et sp. nov. It is described here and this generic name, adopted by the authors, is employed for fossil wood that is believed to be nearly related to the recent genus Sciadopitys and the fossil genus Sciadopityoxylon. The new genus bears some similarities to Protophyllocladoxylon,Protocircoporoxylon and Xenoxylon in different geological ages, but it differs from them in the types of cross-field pitting.     

辽宁北票下白垩统义县组的单子叶被子植物新属种

文章报道可能属于单子叶被子植物化石的两个新属Shangyuania gen．nov．和Zhouia gen．nov．,标本采自辽宁省北票市上园乡黄半吉沟下白垩统义县组尖山沟层。前者属于水生草本植物,具有一个非常细弱的茎,茎保存不全,未见分枝。茎上生有对生和互生的沉水型叶;叶线形,全缘。基部无柄,顶端为钝圆形;具有一条中脉,中脉的两侧各有3—4条细而平行的侧脉和在叶的远轴面上各有一行可能的通气组织;穗状花序生于叶腋中,具有一个细弱的花序梗,由4～5轮小花组成。后者是一个单独保存的种子,卵圆形,被压扁,表面具有多角形的细胞或泡沫状纹饰。通过对两新属形态特征研究和对比,推测它们可能与现生眼子菜科（Potamogetonaceae）,特别是该科中的眼子菜属（Potamogeton）,以及茨藻科（Najadaceae）的茨藻属（Najas）有某种亲缘关系。     

中国逍遥蛛科化石新属种（蜘蛛目，逍遥蛛科）

记述产自中国辽西的逍遥蛛科化石1新属：白垩逍遥蛛属Cretadromus gen．nov．,1新种：辽宁白垩逍遥蛛Cretadromus liaoningensis sp．nov．：这是逍遥蛛科化石在中国的首次发现,也是逍遥蛛科在晚侏罗世-早白垩世的首次报道。标本采白辽宁省凌源市大王杖子晚侏罗世-早白垩世义县组地层,现存于大连自然博物馆：     

Sex determination of the Early Cretaceous clam shrimp Eosestheria middendorfii (Yixian Formation,China)

Clam shrimps have been recognized as a key group for the study of reproductive system evolution, owing to the diversity of sexual systems in extant members. However, there are comparatively little data on fossil taxa. In this study, we reveal the sexual system of the Early Cretaceous clam shrimp Eosestheria middendorfii (Yixian Formation, China). This is the first study that restricts the analysis to a single cohort, minimizing the otherwise considerable impact of ecophenotypic variation within this species. In addition, the presence of egg clutches, which identifies some individuals as either female or hermaphroditic, serves as an independent indicator for sex prior to the statistical treatment of the data. Obligate sexuality (‘dioecy’) is the inferred reproductive system for E. middendorfii and sexual dimorphism accounts for about 10% of the adult shape variation. Carapace shape variation resulting from malformation and deformation is more pronounced than the underlying sexual dimorphism. Subtle sexual dimorphism, smaller and slightly more elongate females, lateral egg clutches, and egg diameters of about 140 μm indicate that E. middendorfii is closely allied with the extant family Cyzicidae.