Lerchenauerstr. 167


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Schlagintweit F.,Lerchenauerstr. 167 | Bucur I.I.,Babes - Bolyai University
Cretaceous Research | Year: 2017

A new larger benthic foraminifera is described as Banatia aninensis n. gen., n. sp. (Family Pfenderinidae Smout & Sugden) from upper Barremian Urgonian-type shallow-water carbonates of the Reşita – Moldova Nouă Zone, southwestern part of Romania. The low to medium trochospiral test of Banatia n. gen. is characterized by marginally undivided chambers and a wide axial part. The latter is made up of pillars continuous between successive chambers and a labyrinthic endoskeleton (plates and pillars) with a fine canal system between. Banatia n. gen. is compared with Pfenderina Henson, Pseudopfenderina Hottinger, and Accordiella Farinacci. The new taxon occurs in algal-foraminiferal wackestones interpreted as deposits of an internal lagoonal realm. So far unrecorded in the literature, the taxon might be paleogeographically restricted (endemic). © 2017 Elsevier Ltd

Schlagintweit F.,Lerchenauerstr. 167 | Rigaud S.,University of Geneva | Wilmsen M.,Senckenberg Naturhistorische Sammlungen
Cretaceous Research | Year: 2015

The small benthic foraminifera Altamirella biscayana n. gen., n. sp. is described from the lower Cenomanian of the Bielba and Altamira formations (North Cantabrian Basin, Spain). Its trochospirally coiled test combines calcitic dark microgranular and fibro-hyaline layers, an arrangement reminiscent of that observed in Palaeozoic Tetrataxidae Galloway. As in Tetrataxis, these layers are built in successive phases and never form a double-layer sensu stricto. The significance of this distinctive wall structure for taxonomy, phylogeny, dispersal, survival and ecology is discussed. A similar wall organization is also observed in some trochospirally coiled Mesozoic forms such as Mohlerina Bucur, Senowbari-Daryan and Abate and might be inherent to epibenthic taxa developing elevated microhabitats. © 2014 Elsevier Ltd.

Thaumatoporellacean algae are widespread constituents in Middle Triassic-Cretaceous shallow-marine carbonates of the Tethyan realm. Based on various examples from Mesozoic limestones of Mediterranean platforms (e. g., Dinaric, Apenninic, Apulia) and rare records of Iberia (Pyrenees), Saudi Arabia and Mexico, it is shown that thaumatoporellaceans commonly dwelt as cryptoendoliths in the tests of larger benthic foraminifera and the thalli of dasycladalean algae. Their high morphological plasticity allowed the test invasion and the adaptation to the available interior spaces (chambers, apertures). The temporal distribution of cryptoendolithic thaumatoporellaceans with first records in the Late Triassic, shows acme intervals in Early-Middle Jurassic and Early-Late Cretaceous times. Within the foraminiferans, the thaumatoporellaceans were erroneously considered as an integral part of the test, respectively, phrenoteca-like structures (species Biokovina gradacensis) in the Lower Jurassic and trematophore (species Scandonea? mediterranea) in the Upper Cretaceous. Therefore, the presence of phrenoteca-like structures in the Biokovinidae, being part of the family diagnosis, is challenged. The comparably thin walls of the cryptoendolithic thaumatoporellacean algae are interpreted as an adaptation to the poorly illuminated microhabitats (photoadaptation) in order to maximize light capture for photosynthesis. © 2011 Springer-Verlag.

The Late Jurassic-Lower Cretaceous microorganisms incertae sedis Lithocodium aggregatum Elliott and Bacinella irregularis Radoičić are taxonomically studied based on material from the Lower Aptian of the western Maestrat Basin (Spain). This study is supplemented with detailed photographs from Elliot's type-material. Given that the original description of Lithocodium aggregatum is ambiguous, a detail from the holotype is chosen as an epitype to serve as an interpretative type (article 9.7 ICBN). Lithocodium is re-interpreted as a filamentous-septate heterotrichale ulvophycean alga (?order Ulotrichales) exhibiting a heteromorphic life cycle consisting of two phases: an epilithic gametophytic and a euendolithic sporophytic (Gomontia stage). Bacinella irregularis is interpreted and redescribed as a purely euendolithic ulvophycean alga which bores into either Lithocodium aggregatum or the substrate below Lithocodium crusts. A small microendolith boring into Lithocodium crusts capable of cryptobiotically stretching within its filamentous network is tentatively assigned to the siphonal chlorophyte Ostreobium Bornet and Flahault. Another associated microfilamentous boring chlorophyte with characteristic long thin hairs (setae) is described as Phaeophila? sp. The euendolithic community comprises a variety of micro- and macroborings that affect the thalli of Lithocodium. Finally, the filaments of the outer zone of the Lithocodium crust are infested by calcimicrobes (cyanobacteria,?fungi). The description made by Elliott in his original work of the "inner layer" of Lithocodium aggregatum as "confused" is explained here as a complex multitaxon chlorophyte-calcimicrobial assemblage overprinted by multiple bioerosion ichnofabrics. © 2010 Springer-Verlag.

The new genus Gosavisiphon with the type-species Halimeda paucimedullaris SCHLAGINTWEIT & EBLI, 1998, tentatively referred to the Udoteaceae, is described from the Late Cretaceous (Middle/Late Cenomanian-Santonian) of the Branderfleck Formation and the Lower Gosau Subgroup of the Northern Calcareous Alps (Austria, Germany). It is a plurimillimetric to pluricentimetric marine, hard-substrate dwelling macroalga, with membraneous and partly fused plates and an internal siphonaceous construction but lacking a real medullary zone. Although some thallus details are still unknown, Gosavisiphon gen. nov. can, from a strictly morphological point of view, directly be compared with the Late Palaeozoic and Upper Triassic phylloid algae. Gosavisiphon gen. nov. is the first fossil record of a platy siphonal alga in the Cretaceous, since the Late Triassic Ivanovia triassica REID. The monotypic taxon is most probably endemic to the Northern Calcareous Alps where it dwelled in protected, terrestrially influenced lagoonal environments attaching to hard substrates, (metazoan skeletons, rudistid shells). Based on findings of the cylindrical Halimeda? aff. johnsoni PAL and another taxon described as Halimeda sp. with typically flattened ovate segments, some considerations on the segment-morphological phylogenetic evolution of Halimeda LAMOUROUX are provided. Halimeda species with discoidal-flattened segments, that can morphologically be compared with extant species, are not known prior to the Turonian. Forms possessing cylindrical segments date further back, but can not directly be compared morphologically with modern counterparts, thus placing doubts on the existence of long-lasting methusalemi species by uniting extant and fossil species, as proposed by both botanists and palaeontologists in recent times.

The present paper compiles an up-to-date taxonomic inventory of dasycladalean green algae of the Kimmeridgian-Early Berriasian Plassen Carbonate Platform and their resediments in basinal sediments (e.g., Barmstein Limestone, Sillenkopf Formation) of the Northern Calcareous Alps of Austria (p.p. Germany). Today, the Plassen Carbonate Platform sensu lato (or Plassen Group) is divided into three independent carbonate platforms with radiolarite deepwater basins between: the Wolfgangsee Carbonate Platform to the north, the Plassen Carbonate Platform sensu stricto in a central position and the Lärchberg Carbonate Platform to the south. All together 42 taxa are reported from these platforms and associated resediments, each shortly commented and illustrated. Amongst these, there are taxa common in all three platforms, others exhibit restricted distributions. These peculiarities can be explained by the different lithostratigraphic and overall geodynamic evolution of the three platforms. In many cases, it allows the assignment of resediments in basinal series to a certain platform as a helpful palaeobiogeographical tool when other data are lacking.

A new microencruster of unknown systematic position is described as Perturbatacrustaleini n. gen., n. sp. from the Late Jurassic Plassen Carbonate Platform of the Northern Calcareous Alps and its resediments (p. p. Barmstein Limestone). The labyrinthic interior canal system and marginal openings reveal a possible sponge origin. Differences and affinities to allied taxa such as Radiomura cautica Senowbari-Daryan and Schäfer are discussed. The biostratigraphic range of Perturbatacrustaleini n. gen., n. sp. known so far is Kimmeridgian to Tithonian (?Early Berriasian) so far reported from Austria, Bulgaria, Romania, and Greece. Perturbatacrustaleini was detected in boundstones with a diverse association of microencrusters and mainly encrusting sponges occurring together with microbial crusts. Together with the other encrusting organisms and reef builders, Perturbatacrusta leini played an important role for the carbonate production and stabilization of the reefal and slope carbonates in the Late Jurassic to earliest Cretaceous of the western Neotethys realm. © 2010 Springer-Verlag.

Slightly curved calcitic plates with marginal pores recalling an aciculariacean alga are common in Late Tithonian reefal platform margin deposits of the Plassen Carbonate Platform of the Northern Calcareous Alps of Austria. Illustrated also from the Western Carpathians, these forms were assigned to the genus Acicularia, e.g., Acicularia elongata Carozzi. It is demonstrated that these algal parts are not reproductive caps of polyphysacean algae (formerly known as acetabulariaceans), but represent sections through scattered articles fragments of the dasycladalean alga Neoteutloporella socialis (Praturlon), more precisely the proximal parts of the laterals. This alga formed reefal bushes at the platform margin near-by to coral-stromatoporoid patches. The characteristic aciculariacean algae recalling fragments occur in bioclastic packstones, a facies adjacent to these dasycladalean algal microreefs. © 2010 Springer-Verlag.

Mohlerina basiliensis (Mohler, 1938) represents a common, cosmopolitan, shallow-water Middle Jurassic-Early Cretaceous trochospiral foraminifer. Given the numerous illustrations from thin-section specimens in the literature displaying tests dispersed within the matrix (micritic and sparitic), a free, vagile benthic mode of life is generally suggested. As an exceptional case, specimens are found with their tests attached to a variety of hard substrates, thus creating a special elevated microhabitat. The fixation is due to a calcitic cement. With its facultative sessile mode of life, Mohlerina can be compared with several modern calcareous trochospiral rotaliacean foraminifera (e. g., Ammonia, Cibicides, Discorbis). The rare preservation of fixed Mohlerina in situ is most likely due to physical taphonomic degradation (e. g., breakage). Tests of Mohlerina attached to hard substrates were found in both low- and high-energy paleoenvironments. The high test variability of Mohlerina might be influenced by the different settling strategies and substrate surface topographies within different paleohabitats. © 2012 Springer-Verlag.

Lithocodium aggregatum Elliott is interpreted as a heterotrichale chlorophycean alga with a prostrate and erect system within a well-calcified tissue. Within Lower Aptian coral rubble of the western Maestrat Basin, Spain, it forms thick masses of juxtaposed crusts around the bioclasts. In achieving a rapid and complete encrustation of the available bioclasts, Lithocodium applied several strategies, e. g., filling voids of structured surfaces with a special fabric or forming erect extensions to bridge adjacent substrates. In these deposits, different types of poorly if ever illuminated cryptic microhabitats can be distinguished: (1) existing crypts such as empty shells or structural voids within bioclasts (2) crypts resulting from the complete encrustation of adjacent bioclasts by Lithocodium itself and (3) syndepositionally created crypts, e. g., boreholes produced by lithophagid bivalves. In these cases, Lithocodium developed a poorly calcified structure of large cells with thin microcrystalline walls indicating a high degree of variability (phenotypic plasticity). This cryptic growth stage is interpreted as an adaption to the poorly illuminated crypts (photoadaption) in order to maximize light capture for photosynthesis. The Lower Cretaceous Lithocodium is therefore not per se a cryptoendolithic microorganism, but may show adaptation to develop and survive also in these already existing or newly created niches. © 2011 Springer-Verlag.

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