Studies on Cenozoic crocodiles: 8.Bergisuchus dietrichbergi Kuhn (Sebecosuchia: Bergisuchidae n. fam.) from the Middle Eocene of Germany, some new systematic and biological conclusions

Bergisuchus dietrichbergi Kuhn is redescribed as a member of its own family, Bergisuchidae n. fam., within the Sebecosuchia. At present, two fragmentary specimens ofBergisuchus are known: the holotype ofBergisuchus, a partial rostrum, comes from the lower part of the Middle Eocene of the Messel pit, near Darmstadt; and a recently discovered fragmentary mandible from the middle part of the Middle Eocene of Geiseltal in an opencast coal-mining pit near Halle (Saale).Bergisuchus shows similarities with species ofSebecus which are known from the Paleocene to Miocene from South America. All palaeoecological and biomechanical data support the hypothesis ofBergisuchus as a small, mainly terrestrial crocodile, which did not build its nests near either of the fossil localities from which it has been collected.     

A large iguanodont from the Upper Barremian of the Paris Basin

The remains of an ornithopod dinosaur from the Upper Barremian (Lower Cretaceous) of Auxerre (Burgundy, France) are described. They consist of several vertebrae and a fragmentary scapula. Despite obvious morphological and dimensional affinities with the species Iguanodon bernissartensis, the state of the specimen does not allow any identification more precise than Iguanodontia indet. Reappraisal of the French Upper Barremian record of medium and large-sized ornithopods reveals that no specimen can be definitely determined to the specific level.     

The dentition of Amygdalodon patagonicus (Dinosauria: Sauropoda) and the dental evolution in basal sauropods

Amygdalodon patagonicus is the oldest record of Sauropoda from South America and is known from several teeth and fragmentary postcranial remains. Here we describe in detail its dental morphology, characterized by the presence of broad spatulated teeth (with low SI values) and the absence of denticles in their crowns. The enamel bears a particular wrinkling pattern composed only of apicobasally-aligned pits, which are frequently joined to each other by a continuous sulcus. Some worn teeth have large wear-facets that extend over only one of the crown's edges. This unique combination of characters provides a proper diagnosis for Amygdalodon. Despite the fragmentary available material, Amygdalodon is here interpreted as a non-eusauropod sauropod based on the results of a phylogenetic analysis. The presence of derived dental characters in Amygdalodon, such as the presence of tooth-tooth occlusion, shows several features previously thought to diagnose Eusauropoda or Gravisauria appeared earlier during the early evolution of sauropods.     

Arboreality,terrestriality and bipedalism

The full publication of Ardipithecus ramidus has particular importance for the origins of hominin bipedality, and strengthens the growing case for an arboreal origin. Palaeontological techniques however inevitably concentrate on details of fragmentary postcranial bones and can benefit from a whole-animal perspective. This can be provided by field studies of locomotor behaviour, which provide a real-world perspective of adaptive context, against which conclusions drawn from palaeontology and comparative osteology may be assessed and honed. Increasingly sophisticated dynamic modelling techniques, validated against experimental data for living animals, offer a different perspective where evolutionary and virtual ablation experiments, impossible for living mammals, may be run in silico, and these can analyse not only the interactions and behaviour of rigid segments but increasingly the effects of compliance, which are of crucial importance in guiding the evolution of an arboreally derived lineage.     

Juvenile ornithopod (Dinosauria: Rhabdodontidae) remains from the Upper Cretaceous (Lower Campanian, Gosau Group) of Muthmannsdorf (Lower Austria)

The fragmentary remains of a juvenile rhabdodontid ornithopod from the Coal-bearing Complex of the Gosau Group (Lower Campanian, Grünbach syncline) at Muthmannsdorf near Wiener Neustadt, Lower Austria are revised. The material, probably belonging to a single individual, includes a right dentary (lectotype of Iguanodon suessi Bunzel, 1871, designated herein), teeth, a fragmentary parietal, fragments of scapula, ?radius, femur, tibia, two vertebrae (lost) and a manual ungual.The lectotype dentary does not provide clear autapomorphies or sufficient diagnostic features to determine its position within the Rhabdodontidae at generic level. By this “Iguanodon suessi” Bunzel, 1871 and the genus “Mochlodon” Seeley, 1881, to which it was latter referred as type species, cannot be characterized sufficiently by differential diagnosis and these are best considered nomina dubia. Based upon combined character comparisons (mainly postcranial features) the Muthmannsdorf ornithopod is referred herein to Zalmoxes Weishampel, Jianu, Csiki and Norman, 2003, a genus so far known from the late Maastrichtian of Romania. It probably but not evidently represents a yet unnamed species, most closely related to Zalmoxes shqiperorum Weishampel, Jianu, Csiki and Norman, 2003. At the present state of knowledge the Austrian material is not further diagnostic at the species level and kept in open nomenclature as Zalmoxes sp.     

First record of a parapithecid primate from the Oligocene of Kenya

Recent excavations in northwestern Kenya have recovered a vertebrate fauna of late early or early late Oligocene age. Among the mammal remains, a fragmentary lower jaw and an isolated upper molar have been attributed to a small primate, Lokonepithecus manai gen. et sp. nov. Lokonepithecus is a primitive member of the Parapithecidae and possibly most closely related to Apidium from the Fayum. The new primate from Kenya is the youngest parapithecid known and its occurrence in the Oligocene of Kenya suggests that sub-Saharan Africa probably played a major role in the evolutionary history of several groups of mammals.     

Discovery of the Jehol Biota from the Celaomiao region and discussion of the Lower Cretaceous of the Bayingebi Basin,northwestern China

Some typical components of the Jehol Biota, including conchostracans Eosestheria sp., the mayfly Ephemeropsis trisetalis Eichwald, 1864, the aquatic beetle Coptoclava longipoda Ping, 1928, and a fragmentary dragonfly, are reported for the first time from the Bayingebi Formation in the Celaomiao region, western Inner Mongolia, China. This discovery indicates that the middle Upper Member of Bayingebi Formation can be correlated with the upper Yixian and the lower Jiufotang formations in western Liaoning Province. Combining it with the radio-isotopic dating result, we further believed that the Upper Member of Bayingebi Formation could be roughly correlated with the Yixian, Jiufotang, and Shahai formations, and the overlying Suhongtu Formation with the Fuxin Formation in western Liaoning Province.In the major Bayingebi Basin, palaeontological and radio-isotopic dating evidence shows that the Bayingebi Formation has a long depositional history of over 30 Ma: its Upper Member bearing the Jehol Biota and the early Fuxin Biota is probably coeval to the Yixian, Jiufotang and Shahai formations and has a Barremian–early Albian age; its Lower Member may be Berriasian–Hauterivian in age and could be correlated with the upper Tuchengzi, Zhangjiakou, and Dabeigou formations in northern Hebei Province. This suggests that the Bayingebi Formation should be promoted to the stratigraphic rank of group and subdivided into several secondary units (formations). Unlike the previous result, the Yingen Formation is considered across the Lower Cretaceous–Upper Cretaceous boundary and being late Albian–early Turonian in age.     

Phylogeny rather than ecology or lifestyle biases the construction of Escherichia coli–Shigella genetic exchange communities

Genetic material can be transmitted not only vertically from parent to offspring, but also laterally (horizontally) from one bacterial lineage to another. Lateral genetic transfer is non-uniform; biases in its nature or frequency construct communities of genetic exchange. These biases have been proposed to arise from phylogenetic relatedness, shared ecology and/or common lifestyle. Here, we test these hypotheses using a graph-based abstraction of inferred genetic-exchange relationships among 27 Escherichia coli and Shigella genomes. We show that although barriers to inter-phylogenetic group lateral transfer are low, E. coli and Shigella are more likely to have exchanged genetic material with close relatives. We find little evidence of bias arising from shared environment or lifestyle. More than one-third of donor–recipient pairs in our analysis show some level of fragmentary gene transfer. Thus, within the E. coli–Shigella clade, intact genes and gene fragments have been disseminated non-uniformly and at appreciable frequency, constructing communities that transgress environmental and lifestyle boundaries.     

对长趾辽宁鸟的重新认识(英文)

早期发现于中国东北热河群的今鸟类化石多呈高度零散保存,本文对于惟一已知的长趾辽宁鸟( Liaoningornis longidigitrus) 标本的研究表明,该分类单元实际上是反鸟类的成员。虽然材料保存较差且破碎,但缺失发达的胸骨、胫骨脊和退化的脚爪,显示其应该被排除于更为进步的鸟胸类( ornithothoracines) 之外。辽宁鸟与所有已知的反鸟均有显著不同,但显示了与西班牙发现的 Eoalulavis hoyasi 的相似性: 它们相似的胸骨特征表明二者可能存在较密切的关系,尽管与其他反鸟类的不同表明,这可能是个体发育造成的假相。由于辽宁鸟标本过于零碎,因此目前难以确定其在反鸟类系统发育中的位置。     

对长趾辽宁鸟的重新认识(英文)

早期发现于中国东北热河群的今鸟类化石多呈高度零散保存,本文对于惟一已知的长趾辽宁鸟( Liaoningornis longidigitrus) 标本的研究表明,该分类单元实际上是反鸟类的成员。虽然材料保存较差且破碎,但缺失发达的胸骨、胫骨脊和退化的脚爪,显示其应该被排除于更为进步的鸟胸类( ornithothoracines) 之外。辽宁鸟与所有已知的反鸟均有显著不同,但显示了与西班牙发现的 Eoalulavis hoyasi 的相似性: 它们相似的胸骨特征表明二者可能存在较密切的关系,尽管与其他反鸟类的不同表明,这可能是个体发育造成的假相。由于辽宁鸟标本过于零碎,因此目前难以确定其在反鸟类系统发育中的位置。     

微生物对烟叶蛋白质含量的影响

经菌株不同浓度、不同菌株、及同浓度不同菌株的等量组合处理过的烟叶放置一段时间未经发酵与发酵后对蛋白质检测,结果表明降解K326中部碎烟叶蛋白质的处理中Y菌株106浓度降解率最高,为18.81%;处理烟叶发酵后,降解率最高的处理是S5菌株107浓度,高达24.46%。K326上部碎烟叶处理后检测结果表明,对蛋白质降解率最高的处理是Y与S8混合,降解率为8.98%;K326上部碎烟叶处理发酵后检测结果表明,S8菌株108浓度处理降解率最高,达24.09%,其次为S5菌株108浓度处理降解率达23.48%。整叶处理结果表明S8降解蛋白质效果最好,降解率达5.17%;整叶处理烟叶发酵后检测S5对烟叶降解率最高,为5.17%。     

Discovery of an archaic Homo sapiens skullcap in Northeast Mongolia

This preliminary study of a human skullcap discovered at Salkhit, Northeast Mongolia, in 2006, shows a mosaic of traits. Plesiomorphies can be seen on the frontal bone: developed brow ridges and a keeled squama. Apomorphies can be observed: high and back-located parietal eminences and absence of a sagittal keel. The skullcap seems to share also some features with Neanderthals that can be observed on the lower part of the frontal bone and in the nasal and orbital region such as a supratoral sulcus, a prominent glabella, prominent rounded lateral supraorbital margins, and a well-defined inward nasion. The comparison of the dimensions of the skullcap with those of skullcaps of a reference sample by multidimensional scaling analysis shows similarities with Neanderthals, Chinese Homo erectus, and West/Far East archaic Homo sapiens. However, the too fragmentary condition of the fossil does not allow any further comparison. Nevertheless, this discovery tackles the modern human origins debate in a region of the world where no human fossil had been discovered before.     

Ankylosaur Remains from the Early Cretaceous (Valanginian) of Northwestern Germany

A fragmentary cervico-pectoral lateral spine and partial humerus of an ankylosaur from the Early Cretaceous (early Valanginian) of Gronau in Westfalen, northwestern Germany, are described. The spine shows closest morphological similarities to the characteristic cervical and pectoral spines of Hylaeosaurus armatus from the late Valanginian of England. An extensive comparison of distal humeri among thyreophoran dinosaurs supports systematic differences in the morphology of the distal condyli between Ankylosauria and Stegosauria and a referral of the Gronau specimen to the former. The humerus fragment indicates a rather small individual, probably in the size range of H. armatus, and both specimens are determined herein as ?Hylaeosaurus sp.. A short overview of other purported ankylosaur material from the Berriasian-Valanginian of northwest Germany shows that, aside from the material described herein, only tracks can be attributed to this clade with confidence at present.     

Anther wall development,placentation, sporogenesis and gametogenesis in Smilax davidiana A.DC: A contribution to the embryology of Smilax

Embryological characters can be used to address taxonomic relationships and complement molecular phylogenetics and are of special value at the genus level. However, embryological information is fragmentary in Smilax and completely unknown in Smilax davidiana, a Chinese species. Anther wall development, placentation, sporogenesis and gametogenesis of S. davidiana are characterized here. The anther is bisporangiate, anther wall formation is of the Dicotyledonous type, both epidermis and endothecium develop fibrous thickenings, and the tapetum is secretory and of dual origin. Cytokinesis in the microsporocyte meiosis is successive, the microspore tetrad is tetragonal, and mature pollen is two-celled. The ovary is mostly trilocular with an axile placentation (a small fraction of the ovaries are unilocular with parietal placentation), the ovule is anatropous, bitegmic and crassinucellate, with embryo sac development of the Polygonum type. This study documents for the first time the embryological characters of S. davidiana in detail and contributes much to the embryology of Smilax.     

Les Spatangus du Miocène et du Pliocène de l’Ouest de la France

Numerous fragments of spatangoid echinoids have been discovered in the Pliocene deposits of Challans, in Vendée (western France). In spite of the fragmentary data of the samples, a reconstitution of a complete test could be realized using the different fragments and their symetrization. The general shape of the test, and its architectural and ornemental characters allow establishing the presence of the genus Spatangus in western France during the end of Neogene. It allows to precise the biogeography of the genus Spatangus and of the morphological group S. (S.) purpureus on the Atlantic coast after the Messinian crisis. The Pliocene species is compared to the Miocene Spatangus (Phymapatagus) brittanus, abundant in Anjou, Brittany and Touraine. This older species was refered to the subgenus Phymapatagus according to the presumed lack of primary tubercles on its posterior interambulacrum. The discovery of well-preserved specimens, with primary tubercles on every parts of the test, in the Middle Miocene of Brittany allows to refute this subgeneric distinction and to refer the species brittanus to the subgenus Spatangus (Spatangus). The presence of this subgenus in western France is finally confirmed from Middle Miocene to Pliocene.     

A fossil record of the Eastern clade of Blanus (Amphisbaenia: Blanidae) from the late Miocene of Ukraine

The fossil history of worm lizards in Eastern Europe is very patchy because of the small number of localities and the fragmentary vertebral material available. A new record of the genus Blanus from the late Miocene of the Egorovka 1 and 2 localities in Ukraine is reported here. Based on its dental morphology, Blanus from Egorovka differs from all extinct species of the genus and from the extant B. cinereus complex. It is most closely related to the Eastern clade of Blanus (B. strauchi complex) in having enlarged second and small third dentary teeth. Blanus from Egorovka is the second fossil record of the B. strauchi complex and the first record of the Eastern clade outside of its current geographical range. It indicates a wider past range of the Eastern European Blanus, including the northern Black Sea coastal area.     

The oldest South American tuco-tuco (late Pliocene,northwestern Argentina) and the boundaries of the genus Ctenomys (Rodentia,Ctenomyidae)

A new species of Ctenomyidae from the late Pliocene of Uquía Formation (northwestern Argentina) is described. The new remains consist of a fragmentary rostrum, and a left mandible with partial lower dentition. Its phylogenetic affinity and morphological specializations for tooth-digging support its assignation to the South American rodent genus Ctenomys. In this context, we highlight the importance of unique morphological specializations for the delimitation of genera within an intrafamilial clade in which similar adaptive strategies could have evolved more than once. The new materials are the oldest fossils for the genus (ca. 3.5 Ma), and their finding in the central Andes agrees with previous hypotheses about the possible area of origin of Ctenomys. They precede by about one million years the presence of Ctenomys chapalmalensis in the Pliocene of the Pampean region of central Argentina, the oldest record previously known for the genus. Nevertheless, the new species does not contribute key information about ancestral character states for the genus beyond those already known through C. chapalmalensis. The phylogenetic, adaptive and even chronological information supplied by these new materials would be linked to the differentiation of the genus rather than to its origin.     

Fishes from the Akkuyu Formation (Tithonian),Western Taurus,Turkey

Two fragmentary fishes are described from theUpper Jurassic (Tithonian) Akkuyu Formation of the Akseki region in the western Taurus (Turkey). Both are determinable, one as a caudal fin of an ichthyodectiform teleost, either Thrissops or Allothrissops, the other as a coelacanthid coelacanth, cf. Undina. This discovery extends the geographic range of these taxa and draw attention to the possibility of collecting a more extensive fish fauna from the region.