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Frankfurt am Main, Germany

This is a review article on the fossil record of turtles in Colombia that includes: the early Cretaceous turtles from Zapatoca and Villa de Leyva localities; the giant turtles from the Paleocene Cerrejón and Calenturitas Coal Mines; the early Miocene, earliest record of Chelus from Pubenza, Cundinamarca; the early to late Miocene large podocnemids, chelids and testudinids from Castilletes, Alta Guajira and La Venta; and the small late Pleistocene kinosternids from Pubenza, Cundinamarca. I also discuss here the current gaps in the fossil record of tropical South American turtles, as well as the ongoing research and future projects to be developed in order to understand better the evolutionary history of Colombian turtles. Source


Cadena E.,Senckenberg Museum | Cadena E.,Smithsonian Tropical Research Institute | Jaramillo C.,Smithsonian Tropical Research Institute
Ameghiniana | Year: 2015

Here we describe the northernmost South American record of fossil turtles from the late early Miocene to early middle Miocene of the Castilletes Formation, on the Alta Guajira Peninsula, Cocinetas basin, Colombia. Turtles in the lower segment of the Castilletes Formation (c. 16.33 Ma) are pleurodires or side-necked turtles belonging to Chelus colombiana Wood, Chelus sp., and Podocnemididae incertae sedis, and cryptodires or hidden-necked turtles attributed to Chelonoidis sp., all of them characterized by the large size of their shells, 1 meter or more total length. The middle segment of the formation (c. 14 Ma) contains specimens of Podocnemididae incertae sedis and Chelonoidis sp. The turtle fauna from Castilletes share taxa with faunas from La Venta (middle-late Miocene of Colombia), Urumaco, and Western Amazonia (late Miocene from Venezuela, Brazil, and Peru); all of these records indicate a wider geographical distribution for podocnemidids, chelids, and testudinids of tropical South America during the early to middle Miocene. The large size of the fossils described here also confirms that gigantism was characteristic of South American tropical turtles during the early Miocene, a trend that lasted at least from the Paleocene to the Pliocene in different lineages. Source


Embry J.-C.,Musee National DHistoire Naturelle | Embry J.-C.,French Institute of Petroleum | Embry J.-C.,Statoil | Vennin E.,Musee National DHistoire Naturelle | And 6 more authors.
Geological Society Special Publication | Year: 2010

A 380 m thick Aptian platform to basin transition has been studied along a 16 km long transect of excellent and continuous outcrops in NE Spain. The series has been dated using biostratigraphy (foraminifera and ammonites) and carbon-isotope stratigraphy, and has been subdivided at four scales of depositional sequences. The Aptian marine succession is subdivided into two-large scale sequences separated by a middle Aptian sub-aerial exposure surface. A characteristic trend of the floral-faunal fossil assemblages is present, which evolves from orbitolinid-ooid dominated ramps in Sequence I-1, to a coral-stromatoporoid-microbialite dominated platform in Sequence I-2, to a rudist-dominated platform top in Sequence II-1, and finally to a second episode of orbitolinid-ooid dominated ramp system in Sequence II-2. There was an influx of siliciclastic sediments at the base and at the top of this succession. The detailed carbon-isotope curve measured along the Miravete section and covering almost the complete Aptian succession, is compared with published Aptian curves recorded in both basinal and carbonate platform settings along the northern and southern Neo Tethys margins. It shows that the Galve sub-basin curve represents all the major isotope excursions of the lower and upper Aptian, in a dominantly shallow-water succession. © The Geological Society of London 2010. Source


Frommel U.,TU Brandenburg | Bohm A.,TU Brandenburg | Nitschke J.,TU Brandenburg | Weinreich J.,TU Brandenburg | And 9 more authors.
Gut Pathogens | Year: 2013

Background: Different strategies of colonization or infection by E. coli result in formation of certain adhesion patterns which help also in classifying intestinal E. coli into pathotypes. Little is known about adhesion patterns and host- and tissue adaption of commensal E. coli and about E. coli originating in clinically healthy hosts carrying pathotype-specific virulence-associated genes. Findings. Adhesion pattern of E. coli (n = 282) from humans and from 18 animal species were verified on intestinal human Caco-2 and porcine IPEC-J2 cells and, furthermore, for comparison on human urinary bladder 5637, porcine kidney PK-15 epithelial and HEp-2 cells. The analysis was carried out on 150,000 images of adhesion assays. Adhesion patterns were very diverse; 88 isolates were completely non-adherent, whereas 194 adhered to at least one cell line with the dominant adhesion patterns "diffusely distributed" and "microcolony formation". Adhesion patterns "chains" and "clumps" were also visible. Chain formation was mediated by the presence of epithelial cells. Clump formation was very specific on only the 5637 cell line. All enteropathogenic (eae §ssup§+§esup§) E. coli (EPEC; n = 14) were able to form microcolonies which was cell line specific for each isolate. Most EPEC formed microcolonies on intestinal IPEC-J2 and Caco-2 but several also on urinary tract cells. Shigatoxin-producing (stx §ssup§+§esup§) E. coli (n = 10) showed no specific adhesion patterns. Conclusions: E. coli isolates were highly diverse. Commensal and pathogenic isolates can adhere in various forms, including diffuse distribution, microcolonies, chains and clumps. Microcolony formation seems to be a global adhesion strategy also for commensal E. coli. © 2013 Frömmel et al.; licensee Bio Med Central Ltd. Source


Frmmel U.,TU Brandenburg | Lehmann W.,Attomol GmbH | Rdiger S.,TU Brandenburg | Bhm A.,TU Brandenburg | And 13 more authors.
Applied and Environmental Microbiology | Year: 2013

Intestinal colonization is influenced by the ability of the bacterium to inhabit a niche, which is based on the expression of colonization factors. Escherichia coli carries a broad range of virulence-associated genes (VAGs) which contribute to intestinal (inVAGs) and extraintestinal (exVAGs) infection. Moreover, initial evidence indicates that inVAGs and exVAGs support intestinal colonization. We developed new screening tools to genotypically and phenotypically characterize E. coli isolates originating in humans, domestic pigs, and 17 wild mammal and avian species. We analyzed 317 isolates for the occurrence of 44 VAGs using a novel multiplex PCR microbead assay (MPMA) and for adhesion to four epithelial cell lines using a new adhesion assay. We correlated data for the definition of new adhesion genes. inVAGs were identified only sporadically, particularly in roe deer (Capreolus capreolus) and the European hedgehog (Erinaceus europaeus). The prevalence of exVAGs depended on isolation from a specific host. Human uropathogenic E. coli isolates carried exVAGs with the highest prevalence, followed by badger (Meles meles) and roe deer isolates. Adhesion was found to be very diverse. Adhesion was specific to cells, host, and tissue, though it was also unspecific. Occurrence of the following VAGs was associated with a higher rate of adhesion to one or more cell lines: afa-dra, daaD, tsh, vat, ibeA, fyuA, mat, sfa-foc, malX, pic, irp2, and papC. In summary, we established new screening methods which enabled us to characterize large numbers of E. coli isolates. We defined reservoirs for potential pathogenic E. coli. We also identified a very broad range of colonization strategies and defined potential new adhesion genes. Source

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