Mayr G.,Senckenberg Forschungsinstitut Und Naturmuseum Frankfurt
Palaeobiodiversity and Palaeoenvironments | Year: 2013
The avian taxon Parvigruidae includes poorly known early Oligocene core Gruiformes, which were considered to be most closely related to either Ralloidea (rails and allies) or Gruoidea (cranes and allies) by earlier authors. Previous fossils of these birds were found in southern France (Parvigrus pohli) and eastern Germany (Rupelrallus saxoniensis). Here, I describe remains of two parvigruid species from the Rupelian stratotype (Boom clay) in Belgium. The smaller of these are tentatively assigned to P. pohli, the larger specimens agree with R. saxoniensis in size but differ in some morphological details and are assigned to a new species, ?Rupelrallus belgicus, sp. nov. The new fossils show that parvigruids were an important part of the early Oligocene European avifauna and had a wide distribution across the continent. They further allow recognition of previously unknown osteological features, especially of the humerus and hypotarsus, which substantiate sister group relationship between Parvigruidae and crown group Gruoidea. © 2012 Senckenberg Gesellschaft für Naturforschung and Springer.
Ruf I.,University of Bonn |
Ruf I.,Senckenberg Forschungsinstitut Und Naturmuseum Frankfurt
Anatomical Record | Year: 2014
In order to elucidate the systematic relevance of the turbinal skeleton in Lagomorpha the ethmoidal regions of 6 ochotonid, 21 leporid, and 2 outgroup species (Sciurus vulgaris, Tupaia sp.) species were investigated by high-resolution computed tomography (μCT). Number and shape of turbinals correspond to major clades and to several genera. All Lagomorpha under study have a deeply excavated nasoturbinal that is continuous with the lamina semicircularis; a feature likely to be an autapomorphy of lagomorphs. In particular, the olfactory turbinals (frontoturbinals, ethmoturbinals, and interturbinals) provide new systematic information. The plesiomorphic lagomorph pattern comprises two frontoturbinals, three ethmoturbinals, and one interturbinal between ethmoturbinal I and II. Ochotonidae are derived from the lagomorph goundplan by loss of ethmoturbinal III; an interturbinal between the two frontoturbinals is an autapomorphy of Leporidae. Pronolagus is apomorphic in having a very slender first ethmoturbinal, but shows a puzzling pattern in decreasing the number of turbinals. Pronolagus rupestris and Romerolagus diazi have independently reduced their turbinals to just two fronto- and two ethmoturbinals, which is the lowest number among the sampled lagomorphs. In contrast, the more derived leporid genera under study (Oryctolagus, Caprolagus, Sylvilagus, and Lepus) show a tendency to increase the number of turbinals, either by developing an ethmoturbinal IV (Caprolagus hispidus, Lepus arcticus) or by additional interturbinals. Intraspecific variation was investigated in Ochotona alpina, Oryctolagus cuniculus, and Lepus europaeus and is restricted to additional interturbinals in the frontoturbinal recess of the two leporids. Anat Rec, 297:2031-2046, 2014. © 2014 Wiley Periodicals, Inc.
Manegold A.,Senckenberg Forschungsinstitut Und Naturmuseum Frankfurt |
Topfer T.,Senckenberg Naturhistorische Sammlungen Dresden
Journal of Zoological Systematics and Evolutionary Research | Year: 2013
The cladistic analysis of 69 morphological and behavioural characters supports the recent DNA sequence-based hypothesis that Hemicircus forms the sister group of all the remaining true woodpeckers (Picinae), but also indicates a sister-group relationship between Dendropicini and Malarpicini, which challenges the results of previous analyses. The present phylogeny further allows a more detailed reconstruction of the stepwise evolution of adaptations for drilling, tapping and climbing up head first on vertical surfaces. The last common ancestor of woodpeckers (Picidae) was neither capable of excavating nest cavities by drilling with its beak nor of climbing up tree trunks. First adaptations for drilling such as reinforced rhamphotheca, frontal overhang and proc. dorsalis pterygoidei evolved in the ancestral lineage of piculets (Picumninae) and true woodpeckers (Picinae s.l.). Further adaptations for drilling and tapping are an enlarged condylus lateralis of the quadrate and fused cotylae mediales and laterales of the lower jaw, but these characters evolved in the ancestral lineage of Picinae s. str. and are primarily lacking in Hemicircus. The inner rectrix pairs became stiffened, and the lamina pygostyli was enlarged in the ancestral lineage of true woodpeckers (Hemicircus + Picinae s. str.). These features can be regarded as first adaptations for climbing up head first and were retained by Hemicircus. In the ancestral lineage of Picinae s. str., however, the tail feathers became further transformed into a specialized support tail, the discus pygostyli became greatly enlarged, and the ectropodactyl toe arrangement evolved. The last mentioned characters might have been the prerequisites for the enormous increase in body size in different lineages of Picinae s. str., namely Megapicini such as Campephilus and Malarpicini such as Dryocopus and Mulleripicus. © 2012 Blackwell Verlag GmbH.
Schindler E.,Senckenberg Forschungsinstitut Und Naturmuseum Frankfurt |
Wehrmann A.,Senckenberg Institute
Palaeogeography, Palaeoclimatology, Palaeoecology | Year: 2011
On the southern flanks of the Tindouf Basin (Western Sahara) reefal complexes of various sizes were developed, mostly of Givetian age but possibly reaching into the early Frasnian. Surrounding sedimentary rocks were dominantly sandstones, siltstones and marls. The larger reef complexes in the northeastern part of Western Sahara show three reef cycles within the Givetian and lowermost Frasnian, interrupted by marly sedimentation. Farther to the west, more isolated reef structures in open shelf settings occur often showing smaller dimensions.The present study focuses on one of these western reefal build-ups. Besides large-scale reefs dominated by stromatoporoids (NE), several smaller bioherms have been investigated, such as the Gwirat Al Hyssan reef-mound near Smara. Initial reef growth was of late Givetian age as indicated by corals (e.g. Heliolites). The main reef builders were the corals Alveolites, Thamnopora, Aulopora, Frechastraea, Phillipsastrea, and, to a lesser degree, Heliolites, Scoliopora, and Roemerolites. Stromatoporoids also contributed, but were less frequent. Chaetetids (e.g. Rhaphidopora) acted as pioneer stabilizers on bare sediment surfaces. Preservation in life position was frequently observed in both groups of organisms. Crinoids are not rare, but only present as debris. In distinct areas of the reef (depressions) concentrations of brachiopods and small solitary corals occur. The reef-mound has a present elevation of 17. m and measures about 370. m in diameter. Vertical as well as horizontal zonation could be recognized in detail. The initial reef growth started on a submarine shoal of siliciclastic sediments, containing various trace fossils and sedimentary structures such as cross-bedding and wave ripples; interference ripples suggest generation in very shallow water. The initial reef-building organisms were encrusting chaetetids, followed by platy Frechastraea colonies; thamnoporids were also present. The overlying reef limestones consist of different corals and, to a minor degree, stromatoporoids. The latter are sparsely distributed vertically as well as horizontally, depending on their position within the reef. Growth forms are more robust (bulbous) towards higher hydrodynamic conditions at the southern reef front. Reef growth is interrupted by debris limestones of thamnoporid and crinoid bioclasts, intercalated with detrital platy stromatoporoids. Generally, the debris was not transported over long distances, as demonstrated by the presence of relatively large fragments. This 'debris phase' (early Frasnian) is overlain by the last documented stage in reef development represented by medium- to thin-bedded coral-rich limestones. The onset of the carbonate production of the Gwirat Al Hyssan reef-mound is maybe related to the global transgressive Givetian-Frasnian Boundary Event. © 2010 Elsevier B.V.
Schindler E.,Senckenberg Forschungsinstitut Und Naturmuseum Frankfurt
Palaeogeography, Palaeoclimatology, Palaeoecology | Year: 2012
The concept of "Time-Specific Facies" (TSF) was proposed in the 1980s by an outstanding palaeontologist/geologist: Otto Heinrich Walliser. His idea of comparing similar developments, which span a certain period of time within the geologic record, offers great potential for age assignment, long-range correlation, studies of palaeoenvironments, and other applications. By not tying his novel idea to a restrictive definition, he enabled present and future scientists to use the term in a relatively broad sense. As with the entire volume, this article pays tribute to this great scientist. © 2012 Elsevier B.V.