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Fossil Representative (fossil + representative)
Selected AbstractsA new fossil species of Polypodium (Polypodiaceae) from the Oligocene of northern Bohemia (Czech Republic)FEDDES REPERTORIUM, Issue 3-4 2001Z. Kvacek A new fossil representative of Polypodium L. emend. CHING (Polypodiaceae s.str.) was recovered in the Early Oligocene diatomite shales of the Ceske stredohori Mountains, North Bohemia (localities Bechlejovice, Holy Kluk hill). Polypodium radonii sp. nova is characterised on the basis of fragmentary fronds, which have simple pinnatifid laminas, entire pinnae, free, anadromously branched venation, solitary broadly elliptic superficial sori and monolete spores in situ of the Polypodiisporites bock-witzensis type. This terrestrial (? to epiphytic or epilithic) fern was associated with vegetation of subtropical Mixed Mesophytic (Holy Kluk) and warm temperate Deciduous Broad-leaved (Bechlejovice) forest types. Actual taxonomy of extant Polypodiaceae s.str. as well as the Tertiary records of this fern group within the Holarctis are reviewed. [source] A stem lineage representative of buttonquails from the Lower Oligocene of Germany , fossil evidence for a charadriiform origin of the TurnicidaeIBIS, Issue 4 2007GERALD MAYR A new species of the charadriiform taxon Turnipax Mayr, 2000 is described from the Lower Oligocene fossil site Frauenweiler in southern Germany. The postcranial skeleton assigned to Turnipax oechslerorum sp. nov. is very well preserved and allows the recognition of significant, previously unknown osteological details of Turnipax, especially concerning the wing and pectoral girdle bones. We provide evidence that Turnipax is a stem lineage representative of the Turnicidae (buttonquails) and synonymize Turnipacidae Mayr, 2000 with Turnicidae Gray, 1840. Turnipax is the earliest fossil representative of the Turnicidae, which otherwise have no Paleogene fossil record. Because recent molecular studies support a charadriiform origin of buttonquails, the mosaic distribution in the skeleton of Turnipax of derived features of the Turnicidae and non-turnicid charadriiform birds is of particular interest. Turnipax exhibits a more plesiomorphic morphology than extant Turnicidae, and we assume that its habitat and way of living differed from that of crown group Turnicidae, which may not have diversified before the spread of grasslands during the Oligocene and Miocene. [source] The evolutionary history of crustacean segmentation: a fossil-based perspectiveEVOLUTION AND DEVELOPMENT, Issue 6 2005Dieter Waloszek Summary The evolution of segmentation in Crustacea, that is, the formation of sclerotized and jointed body somites and arrangement of somites into tagmata, is viewed in light of historical traits and functional constraints. The set of Early to Late Cambrian ,Orsten' arthropods have informed our current views of crustacean evolution considerably. These three-dimensionally preserved fossils document ancient morphologies, as opposed to purely hypothetical models and, because of the unusual preservation of larval stages, provide us with unparalleled insight into the morphogenesis of body somites and their structural equipment. The variety of evolutionary levels represented in the ,Orsten' including lobopodians, tardigrades, and pentastomids also allows phylogenetic interpretations far beyond the Crustacea. The ,Orsten' evidence and data from representatives of the Lower Cambrian Chengjiang biota in southwestern China, including phylogenetically earlier forms, form the major source of our morphology-based review of structural and functional developments that led toward the Crustacea. The principal strategy of arthropods is the simultaneous development of head somites, as expressed in a basal "head larva," and a successive addition of postcephalic somites from a preterminal budding zone with progressive maturation of metameric structures. This can be recognized in the developmental patterns of extant and fossil representatives of several euarthropod taxa, particularly crustaceans, trilobites, and chelicerates (at least basally). The development of these taxa points to an early somite-poor and free-living hatching stage. Embryonic development to a late stage within an egg, as occurring in recent onychophorans and certain in-group euarthropods, is regarded as achieved several times convergently. [source] ,First' appearances in the Cenozoic land-mammal record of the Greater Antilles: significance and comparison with South American and Antarctic recordsJOURNAL OF BIOGEOGRAPHY, Issue 4 2005R.D.E. MacPhee Abstract Aim, Through analysis of fossil records, the aim of this paper is to show that fossil representatives of at least three land-mammal clades (pitheciine atelid primates, heteropsomyine echimyid rodents, and megalonychid phyllophagan xenarthrans) that once lived in the Greater Antilles are as old as, if not older than, ,first' occurrences of these same groups on the South American mainland. Location, Greater Antilles, South America, Antarctic Peninsula. Methods, Analysis of Cenozoic land-mammal fossil records for the three areas. Results, Comparison reveals an interesting similarity to the Tertiary vertebrate palaeontological record for the Antarctic Peninsula (Seymour Island), in the sense that the latter also includes early (Eocene) representatives of some typical ,South American' groups (e.g. meridiungulates, sloths, certain marsupial groups). Conclusions, Given how limited the Antillean and Antarctic records are in quantity and quality, it seems unlikely that these ,first' appearances have much bearing on real origins (basal divergences). Rather, it suggests that the fossil basis for interpreting the origin and earliest diversification of ,South American' clades during the latest Cretaceous/early Cenozoic is probably even scantier than generally realized. In particular, the Antillean record strengthens arguments that some crown-group continental lineages are considerably older than fossil evidence currently allows , a point increasingly (if unevenly) supported by molecular studies of many of the same clades. [source] | ||||||||||