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The density of vertebrate fossils on bedding planes is generally very low in the Upper Jurassic plattenkalks forming the Solnhofen fossil Lagerstatte. There are, however, a few bedding planes where large concentrations of the small fis Leptolepides sprattiformis (BLAINVILLE, 1818) occur. The aim of this paper is to analyse and interpret these f sh concentrations from a taphonomic point of view. For this purpose, the taphonomic features of L. sprattiformis concentrations on three large slabs were semi-quantitatively analysed. The concentrations of individuals on bedding planes are explained as recording local mass mortality events caused by tropical storms that, for short intervals, disrupted the pycnocline which separated hypersaline, oxygen-poor to anoxic bottom waters from normal marine surface waters in the Plattenkalk basins. Mass mortality is supported by tetany features such as gaping jaws, hyperextended branchiostegal rays, and splayed f ns, which occur in the majority of the specimens. The generally excellent preservation of the f sh resulted from lack of postmortem f oatation, rapid burial and/or overgrowth by microbial f lms, and quick re-establishment of the pycnocline with inhospitable conditions on the basin floo. The post-mortem concave-arching of the backbones and various displacements of the vertebral column were most likely caused by varying decay resistance of soft tissues and the pressure of decay gases in the body cavities, respectively. The taphonomic analysis of f sh concentrations can provide very detailed palaeoenvironmental information and serves as an independent line of evidence for palaeoenvironmental reconstructions that complements geochemical and sedimentary data.

A collection of 93 Late Jurassic gastropods from the Kachchh Basin in western India represents 23 species. The material contains new records, such as Purpurina sp., as well as five new species: Bathrotomaria densireticulata, Bathrotomaria depressa, Bathrotomaria gangtaensis, Neritopsis indica, and Eucyclus tramauensis. Additional unnamed species occur, but since they are represented only by single and/or fragmentary specimens in the present collection, they have been left in open nomenclature. The majority of the described gastropods are from the Oxfordian part of the Jurassic succession of the Kachchh Basin. The fauna is strongly dominated by pleurotomariids and resembles that of palaeogeographically neighbouring areas (especially Madagascar) in composition. Most of the occurring genera are wide-ranging and known from localities throughout the Tethyan Ocean, but a strong endemism at the species level seems evident.

Forty-three ammonites from the Kachchh Basin in western India have been assigned to seven taxa belonging to the genus Peltoceratoides sPAth, 1924. The two most abundant morphospe- cies Peltoceratoides (Peltoceratoides) constantii and Peltoceratoides (Parawedekindia) arduennen- sis are commonly considered as the macro- and microconch, respectively of a single biospecies. The taxa are important for intrabasinal as well as intercontinental correlation due to their wide geographic range during the Early Oxfordian. The specimens occur in beds, which had been assigned to the Cor- datum Zone, but also reworked in the so-called Dhosa Conglomerate Bed, which contains an array of ammonites from different ammonite zones.

The new ichnospecies Cellicalichnus antiquus from upper Lower to lower Middle Jurassic strata of the Shemshak Group of north-eastern Iran consists of bundles of horizontal tunnels, from which at regular intervals elongate cells opposing each other emerge. The burrow has been constructed in floodplain deposits of a braided river system. It is interpreted as an arthropod brood structure of either insects, most likely hymenopterans, which may belong to the ancestral stock of soil-dwelling bees, or else of terrestrial crustaceans (crayfishes).

Lithological and especially palacontological data allow reconstruction of the palaeogeographic history of Hohxil, the source area of the Yangtze River in the northern Tibet Plateau, since the Late Palaeozoic. Early Carboniferous - Early Permian deep water environments, part of the Palaeotethys, were replaced by a Late Permian shelf sea following convergence of the Qiangtang and Kunlun blocks. During the Triassic, a varied facies pattern existed with open shelf to deep sea sediments in the north and non-marine to marginally marine environments in the south. Renewed compression between the Qiangtang and Kunlun blocks at the end of the Triassic led to formation of a mountain range. Subsequently, it was only during the Middle Jurassic that, due to renewed transgression, a shallow shelf sea extended into the southern parts of Hohxil. Collision of the Lhasa block with the Qiangtang block at the end of the Jurassic caused the final retreat of the sea from the area. From the Cretaceous throughout most of the Tertiary, lacustrine and fluvial sedimentation prevailed, with a distinct sedimentary gap during the Paleocene and Eocene due to collision of the Indian and Eurasian plates. Pliocene events include volcanic eruptions and strong uplift, the latter continuing to the present day, resulting in an average altitude of the area of more than 5,000 in; this extremely elevated region became the source of the Yangtze River.