Lukas Hottinger’s research while affiliated with University of Basel and other places

This book provides a representative assessment of the state of the art of research on Paleogene rotaliid larger foraminifera. It gives an overview of the current understanding of systematics of this group and, in particular, of its biostratigraphic importance and palaeobiogeography. The senior author of the work, late Professor Hottinger, a leading scientist in the field, both from a systematic and applied side, presents in this book his most recent advances. The foraminiferal family Rotaliidae is a traditional group used frequently which plays an important role for petroleum exploration in the biostratigraphy and palaeobiogeography of Paleogene shallow water deposits in the Middle East. This book aims to introduce rotaliid representatives as index fossils that can be recognized in random thin-sections of cemented rocks. The book is generously illustrated with an unprecedented degree of accuracy. The selection of taxa is restricted to forms having lived in the Paleocene and the Eocene, where their biostratigraphic significance is much higher than during later epochs. However, some additional rotaliid taxa, from the Late Cretaceous or that do not belong to the family Rotaliidae sensu stricto, are included in this book in order to demonstrate particular roots of rotaliid phylogenetic lineages in the previous community maturation cycle or to delimit the taxon Rotaliidae with more precision. This book can be considered as a reference in the field.

During the global community maturation cycle starting at the Cenomanian- Turonian boundary and ending with the events at the K-T boundary, the rotaliid foraminifera produce for the first time in Earth History a considerable diversity of K- strategists that exhibit large shell sizes, complex umbilical structures and an important dimorphism of generations. In the Late Cretaceous Pyrenean Gulf four groups are distinguished. 1. Closest to the Cenomanian progenitor Rotorbinella mesogeensis (Tronchetti, 1981) are Rotorbinella campaniola n. sp. and Pyrenerotalia longifolia n. gen. n. sp. characterized by an increasing elongation of the folia. Iberorotalia n. gen. reicheli (Hottinger, 1966) belongs to the same group but produces a heavy ornamentation on the umbilical face that modifies and complicates the umbilical structure. 2. Orbitokathina with its species O. vonderschmitti Hottinger, 1966 and O. campaniana n. sp. are related to the Paleocene group of Kathina that is also present in the Caribbean Late Cretaceous. 3. The pararotaliids (with a toothplate, an umbilical structure that is controversial) remain conservative during the Late Cretaceous and produce only much later, in the Late Oligocene, larger foraminifera, namely the miogypsinids. 4. Calcarinella n. gen. schaubi (Hottinger, 1966) is considered to be closer to Calcarina than to Pseudorotalia or Lockhartia and therefore is transferred to the calcarinines. The large-sized rotaliids of the Late Cretaceous unfold their diversity in the Early Santonian, at the usual distance of about ten million years from the start of the maturation cycle, but their diversity and abundance is reduced later under the competition of the rising siderolitines and orbitoids during the Campanian-Maaestrichtian.

Shallow, restricted carbonate facies in the Late Cretaceous yield on both sides of the Atlantic axially compressed, discoidal, and axially elongate, fusiform alveolinacean shells. Their structural analysis reveals that the taxa involved are dissimilar on both sides of the Atlantic. The structural differences warrant separate generic names for the alveolinacean associations on either side of the Atlantic. Two of them, Fabalveolina and Caribalveolina, are new. An important element of distinction is found in the endoskeleton: solid basal layers, that constitute the median zone of the discs and the columellas of the fusiform shells, may be pierced by tubular supplemental passages or the same shell elements may be constructed by septula and floors delimiting more regular stacks of chamberlets in supplemental layers. Fusiform alveolinaceans are restricted to two realms on the shores of the Atlantic, the Caribbean in the West and the Pyrenean Gulf in the East. Compressed alveolinaceans characterize the Caribbean on one hand, the Western Neotethys on the other. They seem to be absent from the Pyrenean Gulf, where they might be substituted by the Meandropsinidae. This emphasises the importance of the Pyrenean Gulf as separate faunal province.

The Meandropsinids are defined by their diaphanous umbo in their porcelaneous shells that is always present at least in their microspheric generation. The extent of the development of their endoskeleton depends on the relative length of their apertural face of the spiral to annular chambers. The alar prolongations of the spiral chambers are subdivided by ridges or complete septular walls arising from the basal layer of the chamber. These endoskeletal elements are aligned in subsequent chambers but interrupted by preseptal passages. All members of the family Meandropsinidae occur within the Senonian and are restricted to the Late Cretaceous Pyrenean Gulf, except the most simple and small-sized members Nummofallotia and Eofallotia. In Spirapertolina and Larrazetia only microspheric specimens have been found. The large-sized members of the Meandropsinid family are interpreted as endemists in the Pyrenean Gulf in analogy to the larger sized representatives of the family Lacazinidae. The results of the structural analysis of the Meandropsinidae oblige to introduce the following new linnéan names: Eofallotia simplex n. gen. n. sp., Fascispira schlumbergeri n. sp. and Alexina papyracea n. gen. n. sp.

Boueina pacifica Ishijima, 1978, found in Aptian shallow-water carbonates from Seberuang (Indonesia), was originally ascribed to the calcareous halimedacean algae (Chlorophyta). However, during a taxonomic revision of Ishijima’s types of Corallinales (Rhodophyta) described from 1954 to 1978, the type specimens of Boueina pacifica Ishijima 1978—currently housed at the Geology and Paleontology Department, National Museum of Nature and Science, Tokyo (Japan)—have been identified as an orbitolinid foraminifer. The types have a microgranular shell texture with clearly distinguishable exoskeletal and endoskeletal shell structures diagnostic of the larger foraminiferal subfamily Orbitolininae. Unfortunately, “Boueina” pacifica Ishijima has no diagnostic features that can be used to ally it to any particular genus or species of the orbitolinids.

The Miscellaneidae are divided into two groups of species: forms with a single intercameral foramen and forms with two or a row of multiple foramina. Ten taxa ascribed to this family are revised, amply illustrated and discussed considering both micro- and megalospheric generations. The Family Miscellaneidae is assigned to the Superfamily Nonionacea by reason of their planispiral-involute coiling combined with an interiomarginal position of the foramina. Their combined range covers SBZ zones 2-5 and an area comprising the Central and Western Neotethys including the Pyrenean Gulf. They do not reach the western shores of the Atlantic. Miscellanites meandrinus and Bolkarina aksarayi exhibit extreme morphological features, respectively meandrine alar extensions and expanse chambers. These features are of general interest for the comparative anatomy of the shells of the larger foraminifera in order to understand their biological significance.

The Kozara Mountains of northern Bosnia and Hercegovina form part of the internal Dinarides and host two tectonically juxtaposed ophiolitic successions of different age. The southern part of the Kozara Mountains exposes the Western Vardar Ophiolitic Unit, which was obducted onto the Adriatic margin in the Late Jurassic. The northern part exposes a bimodal igneous succession that was thrust onto the Western Vardar Ophiolitic Unit during the latest Cretaceous to Early Paleogene. This bimodal igneous succession comprises isotropic gabbros, doleritic dikes, basaltic pillow lavas and rhyolites. Pelagic limestones, intercalated with pillow lavas, yielded a Campanian globotruncanid association, consistent with concordant U–Pb ages on zircons from dolerites and rhyolites of 81.39 ± 0.11 and 81.6 ± 0.12 Ma, respectively.