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Bentonitized tuffites in the Lower Eocene deposits of the Subsilesian Unit (Western Outer Carpathians, Poland): lithology, stratigraphic position and mineral composition

100%

Cieszkowski M. , Środoń J. , Waśkowska-Oliwa A. , Leśniak T.

tom Vol. 76, No 2

197-214

New occurrences of bentonitized tuffites were described from numerous outcrops of the Lower Eocene flysch rocks of the Subsilesian Unit. These deposits crop out in the Żywiec tectonic window and in the tectonic windows of the Lanckorona - Żegocina Structural Zone. The bentonitized tuffites, composed of almost pure dioctahedral motmorillonite, form numerous thin layers and laminae, only occasionally exceeding 5 cm. The age of the tuffites is estimated as the Early Eocene (Glomospira div. sp. and Saccamminoides carpathicus zones) on the basis of foraminiferal assemblages. They occur in the upper part of green shales and in the lower part of the Lipowa beds that consist mainly of muddy turbidites represented by green or green-brownish shales with rare intercalations of sandstones. The sedimentary sequences with the tuffite intercalations form a lithostratigraphic level in the Subsilesian Unit called in the present paper "the Glichów Tuffite Horizon". This tuffite horizon could probably be correlated with deposits of similar age containing tuffites which are known from the Magura, Silesian and Skole nappes.

New early Eocene tapiromorph perissodactyls from the Ghazij Formation of Pakistan, with implications for mammalian biochronology in Asia

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Missiaen P. , Gingerich P. D.

nr 1

Early Eocene mammals from Indo−Pakistan have only recently come under study. Here we describe the first tapiromorph perissodactyls from the subcontinent. Gandheralophus minor gen. et sp. nov. and G. robustus sp. nov. are two species of Isectolophidae differing in size and in reduction of the anterior dentition. Gandheralophus is probably derived from a primitive isectolophid such as Orientolophus hengdongensis from the earliest Eocene of China, and may be part of a South Asian lineage that also contains Karagalax from the middle Eocene of Pakistan. Two specimens are referred to a new, unnamed species of Lophialetidae. Finally, a highly diagnostic M3 and a molar fragment are described as the new eomoropid chalicothere Litolophus ghazijensissp. nov. The perissodactyls described here, in contrast to most other mammalian groups published from the early Eocene of Indo−Pakistan, are most closely related to forms known from East and Central Asia, where Eocene tapiromorphs are diverse and biochronologically important. Our results therefore allow the first biochronological correlation between early Eocene mammal faunas in Indo−Pakistan and the rest of Asia. We suggest that the upper Ghazij Formation of Pakistan is best correlated with the middle or late part of the Bumbanian Asian Land Mammal Age, while the Kuldana and Subathu Formations of Pakistan and India are best correlated with the Arshantan Asian Land Mammal Age.

A new short-legged landbird from the Early Eocene of Wyoming and contemporaneous European sites

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Mayr G. , Daniels M.

tom 46

nr 3

Fluvioviridavis platyrhamphus, a new genus and species of short-legged landbirds from the Lower Eocene Green fiver Formation (Wyoming, USA) is described. The taxon is known from a single, nearly complete and slightly dissociated skeleton which was made the paratype of the putative oilbird Prefica nivea Olson, 1987 (Steatornithidae, Caprimulgiformes). Apart from the greatly abbreviated tarsometatarsus, Fluvioviridavis especially corresponds to recent oilbirds in the unusually wide proximal end of the humerus. However, in other features, e.g., the shape of its much longer beak, the Eocene taxon is clearly distinguished from the recent oilbird (Steatornis). In contrast, Prefica nivea agrees with Steatornis in the shape of the mandible but differs in the much narrower proximal end of the humerus. At present, no derived character convincingly supports a classification of F. platyrhamphus into any of the higher avian taxa. The species is here classified 'order and family incertae sedis'. An isolated skull from the Middle Eocene of Messel (Hessen, Germany) is tentatively assigned to ?Fluvioviridavis sp., and associated bones from the Lower Eocene London Clay of Walton-on-the-Naze (Essex, England) might also be related to the genus Fluvioviridavis.

W pracy opisano nowy rodzaj i gatunek krótkonogiego ptaka lądowego nazwanego Fluvioviridavis platyrhamphus, z wczesnoeoceńskiej formacji Green River (Wyoming, USA). Takson ten jest znany z jednego prawie kompletnego i nieco rozproszonego szkieletu, ustanowionego jako paratyp domniemanego kopalnego tłuszczaka Prefica nivea Olson, 1987 (Steatornithidae, Caprimulgiformes). Oprócz silnie skróconych kości skoku, Fluvioviridavis nawiązuje do współczesnych tłuszczaków bardzo szeroką nasadą kości ramiennej. Jednak pod innymi względami, np. kształtem znacznie bardziej wydłużonego dzioba, eoceński takson wyraźnie różni się od współczesnego tłuszczaka (Steatornis), natomiast Prefica nivea ma kształt szczęki podobny jak Steatornis, ale różni się odeń o wyraźnie węższą nasadą kości ramiennej. Obecnie nie można wskazać żadnej apomorfii przekonująco wiążącej F. platyrhamphus z jakimkolwiek taksonem wyższej rangi, toteż rodzaj i gatunek ten uznano w niniejszej pracy za reprezentujący ,,rodzinę i rząd incertae sedis". Pojedyncza czaszka ze środkowego eocenu Messel (Hesja, Niemcy) została prowizorycznie zaliczona do ?Fluvioviridavis sp.; do rodzaju Fluvioviridavis mogą też należeć kości z wczesnoeoceńskich iłów londyńskich (London Clay) z Walton-on-the-Naze (Essex, Anglia).

Crustacean burrows from Upper Maastrichtian deposits of South-Central Cuba

58%

Pszczolkowski A.

nr 2