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Nineteen late Albian ammonite taxa and one nautiloid species belonging to eight genera and four families are systematically described from reddish coarse-grained bioclastic packstones to rudstones of the Grab well section (Kosmaj Mountain), Vardar Zone of central Serbia. Among the identified taxa, the nautiloid Eutrephoceras cf. clementianum (d’Orbigny, 1840) and seven ammonite taxa, Tetragonites rectangularis Wiedmann, 1962, Puzosia provincialis (Parona and Bonarelli, 1897), Bhimaites cf. pinguis (Crick, 1907), Beudanticeras (Beudanticeras) cf. beudanti (Brongniart, 1822), Hysteroceras cf. pseudocornutum Spath, 1934, Mortoniceras (Subschloenbachia) rostratum (J. Sowerby, 1817), and M. (S.) cf. perinflatum (Spath, 1922) are recorded for the first time from Serbia. The identified taxa are typical representatives of the Tethyan faunal province. Ammonite taxa provide the first reliable biostratigraphic dating of the Grab well section of central Serbia. The reddish coarse-grained bioclastic packstones to rudstones (a 0.5-m-thick lens) belong to the upper Albian, which is proven by ammonites of the uppermost Albian Mortoniceras rostratum and M. perinflatum zones and the early late Albian brancoceratines Hysteroceras orbignyi (Spath, 1922), H. choffati Spath, 1925, and H. varicosum (J. de C. Sowerby, 1824), which are equivalent to the M. pricei, M. inflatum, and M. fallax zones. The overlying 3.5 m of sandy packstones are assigned to the earliest Cenomanian based on the brachiopods Capillithyris capillata (d’Archiac, 1847) and Terebrirostra lyra (J. Sowerby, 1816), which characterize the lowermost Cenomanian Mantelliceras mantelli Zone. The upper part of the Grab well section (20 m in bedded silty marlstones and marly siltstones) is assigned to lower middle Cenomanian based on the presence of the Turrilites costatus Subzone.

Biostratigraphy of ammonite, inoceramid and orbitolinid foraminifer faunas from the mid-Cretaceous (Aptian–Turonian) succession at the eastern border of the Anarak Metamorphic Complex, a basement uplift in the north-western part of Central Iran, helped to understand complex lithostratigraphic patterns, to trace tectonic unconformities and to reconstruct the geodynamic significance of the succession. The basal continental Noqreh Formation can only be dated by stratigraphic superposition as pre-late early Aptian. An orbitolinid assemblage in the overlying shallow-marine Shah-Kuh Formation indicates a latest early Aptian age. The lower member of the overlying Bazyab Formation documents a considerable deepening in the early late Aptian (Epicheloniceras subnodosocostatum Zone). The boundary to the middle member of the Bazyab Formation is a conspicuous sedimentary unconformity, separating marly offshore strata below from shallow-marine, bioclastic sandstone above. The upper part of the middle member yielded ammonites of the upper lower Albian Douvilleiceras mammillatum Zone. In the upper member of the Bazyab Formation, ammonites of the upper Albian Mortoniceras rostratum Zone have been found. The base of the overlying Debarsu Formation is of earliest Cenomanian age (Mantelliceras mantelli Zone, Neostlingoceras carcitanense Subzone) and lower Cenomanian shallow-marine limestones range up to an intra-formational unconformity below the upper marl member of the formation, yielding early Turonian inoceramid bivalves and ammonites in the lower part. The Debarsu Formation is truncated along a major regional unconformity at the base of the Haftoman Formation. The erosional episode is correlated to a Coniacian tectonic event but further studies are needed to fully understand its geodynamic significance.

Two brachiopod species belonging to two genera, two families, and one order and nine echinoid taxa (five regular and four irregular) belonging to eight genera, seven families, and seven orders are revised and systematically described from reddish coarse-grained bioclastic packstones to rudstones of the Grab spring section (Kosmaj Mountain) of the Vardar Zone of central Serbia. The stratigraphic range and the palaeobiogeographic distribution are given for each species. Five echinoid species, “ Cidaris ” strombecki (Desor, 1858), Leptosalenia cf. prestensis (Desor, 1856), Tetragramma variolare subnudum (Agassiz, 1846), Conulus ( Conulopyrina ) vionneti (Desor, 1857), and C. ( Conulus ) castanea (Brongniart, 1822) are recorded from the lower Cenomanian of Serbia for the first time. Earlier on, the benthic macrofauna of the section has been assigned an Albian–Cenomanian age. Although the upper Albian–lower Cenomanian boundary is covered by debris, the presence of the lower Cenomanian larger foraminiferal zone [ Orbitolina ( Conicorbitolina ) conica ] allows to assign the lower part of the Cenomanian succession certainly to the lower Cenomanian. The O . ( C .) conica Zone overlies the uppermost Albian planktonic foraminiferal Thalmanninella appenninica and the ammonite Puzosia planulata zones. Most of the brachiopods and echinoids are predominantly confined to the northern margin of the Tethyan realm and some species are also known from the southern margin of the Tethys and from north-eastern Brazil. The distribution patterns of the taxa were probably influenced by east-west directed currents during the early Cenomanian time. The identified taxa are associated with other macrofaunal elements such as ammonites, bivalves, gastropods, and corals. The presence of stenohaline groups document euhaline conditions. The high degree of fragmentation, disarticulated bivalves, and the upward oriented of the adoral surfaces of most echinoids suggest that the organisms lived in moderately agitated subtidal environments and suffered post-mortem transport.

Sixteen early and middle Albian bivalve species, belonging to fourteen genera, eleven families and seven orders, and one brachiopod species are systematically described from the Mitrovcic section near Topola (Oplenac Hill), Vardar Zone of central Serbia. Four bivalve species: Acesta subrigida (Roemer, 1836), Acesta cf. dorbignyana (Matheron, 1843), Neithea (Neithea) sexcostata (S. Woodward, 1833), “Cardium” cottaldinum d'Orbigny, 1844, and one terebratulide species, Praelongithyris rogeri Gaspard, 1974 are recorded from the lower and middle Albian rocks of central Serbia for the first time. The section comprises reddish ferruginous calcareous sandstones that are assigned to the lower Albian as indicated by the presence of the ammonite Douvilleiceras mammillatum (Schlotheim), while yellowish sandy wackestones/packstones located below the late Albian Mortoniceras (M.) inflatum (J. Sowerby), are middle Albian in age. Most of the identified bivalve taxa have a Tethyan affinity and seem to be closest to faunas from western and eastern Europe. This indicates that these regions were close to Serbia during the early–middle Albian. The occurrences of some of these Tethyan bivalves at the northern and western Pacific coast of South America and southern coast of North America is explained by dispersal through the opening of the North Atlantic Ocean during the Albian (Proto-North Atlantic Ocean). Meanwhile, the occurrence of some other Albian taxa along the eastern coast of South America (South Atlantic) was probably a result of the opening of the equatorial Atlantic gateway during that time. The faunas are not endemic, indicating that the larvae were long-lived and possessed a high dispersal potential, facilitated by seaways during the Albian.

Fossils from the “Jehol Biota” have been studied for nearly 90 years, and the term “Jehol Biota” has been extensively used and is well known today, largely thanks to the discovery of feathered dinosaurs, angiosperms, and numerous other exceptionally preserved fossils in the Lower Cretaceous of northeastern China. Ironically, however, what exactly the Jehol Biota represents and how it is defined has hardly been discussed. The lack of a precise definition of the Jehol Biota has hindered our understanding of such important issues as its palaeodiversity, its spatial and temporal distribution, and the pattern of radiation of the biota. In this paper, we propose that the Jehol Biota is defined by using a palaeoecological concept, and by combining ecological and taphonomic aspects, i.e., as organisms that lived in the Early Cretaceous volcanic-influenced environments of northeastern China, and were buried in lacustrine and rarely fluvial sediments, where most turned into exceptionally preserved fossils. The relationship between the Jehol Biota and the Jehol Group is also clarified. According to the revised definition, the Jehol Biota is so far only discovered in deposits of the Yixian and Jiufotang formations of western Liaoning, adjacent Inner Mongolia, and northern Hebei, and the Huajiying Formation of northern Hebei. Tempo

The Shah Kuh Formation of the Khur area (Central Iran) consists of predominantly micritic, thick-bedded shallow-water carbonates, which are rich in orbitolinid foraminifera and rudists. It represents a late(est) Barremian – Early Aptian carbonate platform and overlies Upper Jurassic – Barremian continental and marginal marine sediments (Chah Palang and Noqreh formations); it is overlain by basinal deposits of the Upper Aptian – Upper Albian Bazyab Formation. The lithofacies changes at both, the base and top of the Shah Kuh Formation are gradational, showing that the formation is part of an overall transgressive sedimentary megacycle, and that the formational boundaries are potentially diachronous on larger distances. Analyses of facies and stratal geometries suggest that the Shah Kuh carbonate system started as a narrow, high-energy shelf that developed into a large-scale, flat-topped rudist platform without marginal rim or steep slope. The Shah Kuh Platform is part of a large depositional system of epeiric shallow-water carbonates that characterized large parts of present-day Iran during Late Barremian – Aptian times (“ Orbitolina limestones” of NW and Central Iran, the Alborz and the Koppeh Dagh). Their biofacies is very similar to contemporaneous deposits from the western Tethys and eastern Arabia, and they form an important, hitherto poorly known component of the Tethyan warm-water carbonate platform belt.

A small faunule of the calcareous sponge Porosphaera globularis ( Phillips, 1829 ) (Calcarea, Minchinellidae) is described and illustrated from the Maastrichtian Farokhi Formation of Central Iran. The shape of the sponges varies from near-spherical to pyriform with diameters ranging between 5 and 13 mm. The surfaces show small, equidistant apertures corresponding to radiating oscular tubes within a choanosomal skeleton consisting of large tetractines fused to a rigid framework. Radially arranged superficial grooves may also be present in some specimens. External attachment scars have not been observed, but perforations in two specimens may represent sipunculan worm borings. A quiet and fairly deep-water environment can be inferred as the habitat of the sponges, corresponding to data in the literature. So far, P. globularis was known only from the Upper Cretaceous (Cenomanian–Maastrichtian) of the Boreal Realm. The record from Central Iran is the southernmost occurrence of P. globularis (palaeo-latitude ca. 20°N) known to date and is the first description of the species from Iran and the Middle East.

A Turonian ammonite faunule from the Shotori Mountains (east-central Iran) with Thomasites koulabicus (Kler) and Collignoniceras woollgari regulare (Haas) is recorded for the first time and briefly described. Thomasites koulabicus appears, in contrast to the widely distributed C. w. regulare , to be restricted to central East Asia. Its occurrence in east-central Iran provides new insights into the Turonian ammonite palaeobiogeography of the area. The ammonites document a Cretaceous marine transgression onto the Shotori Mountains in the central part of the Central-East Iranian Microcontinent during the Early–Middle Turonian. The nearshore character of the host sediments, a strong terrigenous input, and the intercalation of conglomerates originating from nearby cliffs suggest that at least portions of the Shotori Mountains defied inundation by the Turonian sea. This “Shotori Island” was surrounded by shelf seas and narrow oceanic basins, forming an important palaeogeographical feature in the Tethysides of the Middle East during the Late Cretaceous.