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Fragmentary isolated remains of large (up to 20 m or more) sauropods from the Middle Jurassic (Bajocian) Khadir Formation of Khadir Island (Kachchh, W India) are described and compared in detail. Three of the bone fragments (a metacarpal, a first pedal claw and a fibula) can be assigned with confidence to the Camarasauromorpha and represent the oldest known record of that derived dinosaur group. The new finds from western India further close a temporal and geographical gap in our knowledge of sauropods and contribute to understanding their early phylogeny.

In the Jajarm area (eastern Alborz Mountains, NE Iran) the ?Upper Triassic — Lower Bajocian siliciclastic Shemshak Formation is up to 2000 m thick. Whereas the lower third of the formation is nearly exclusively non-marine, the upper two-thirds are fully marine. The middle part is characterized by several levels containing a relatively diverse and well preserved assemblage of ammonites of the Toarcian to Aalenian stages. Two sections of the ammonite-bearing strata, spaced 20 km, are presented and correlated by means of ammonite biostratigraphy. The ammonite fauna consists of 27 taxa, some of which are recorded for the first time from the Alborz Mountains. The ammonites are briefly described and their palaeobiogeographic context is reviewed. The ammonite fauna of the Shemshak Formation at Jajarm, as elsewhere in North and Central Iran, is exclusively Northwestern Tethyan in character and is closely related to the faunas of Northwestern and Central Europe.

CyathophoraMichelin, 1843, hitherto well known from the Upper Jurassic and Cretaceous, has been found in the Middle Jurassic (Bajocian) of the Kachchh Basin, western India. Eleven specimens ofCyathophora bourgueti (Defrance, 1826) from the Babia Cliff Sandstone member of the Kaladongar Formation, exposed along the northern scarp of the Kala Dongar, Pachchham Island, Kachchh, are described and illustrated as the earliest Jurassic record of the family CyathophoridaeVaughan & Wells, 1943. It is suggested that the monospecific occurrence ofCyathophora bourgueti was controlled by salinity.

From the Late Bathonian sponge biofacies at Jumara Dome, Kachchh (western India) 11 species of ‘lithistid’, hexactinellinid and calcarean sponges are described. New taxa are the order Sigmatospirida, the genusJumarella, and the speciesJumarella astrorhiza, Mastosia rhytidodes, Radicispongia kraspedophora, andHexactinella prisca. The diverse sponge assemblage is associated with a rich fauna of epibenthic bivalves and brachiopods and formed meadows on fine-grained carbonate substrates. The sponge meadows grew on a carbonate ramp at the lower end of the photic zone, in quiet waters below storm wave base. The rate of sedimentation exceeded that of sponge production. This prevented the development of reef-like bodies. In contrast to Mesozoic sponge reefs, growth of the sponge meadows appears to have been confined to the regressive phases of small transgressive-regressive cycles.

An endemic brackish water faunule consisting of three taxa of bivalves,Hudsonella sinensis (Chen) n. gen.,Hudsonella sp., andProtocardia hepingxiangensis Chen & Lin occurs in the Bajocian of the southern Qinghai province, China.Hudsonella sinensis is a very variable species with a hinge structure characteristic of the subfamily Pachydontinae of the family Corbulidae. According to both geochemical data (stable carbon isotopes and the strontium/barium ratio) and ecological data the faunule lived in a brackish water embayment of mesohaline salinity (5#x2013;18 per mil) burrowing in soft substrate.

TheComophyllia polymorpha-Crispispongia cf.expansa association of the Kimmeridgian Alcobaca Formation occurs in a 5–10 m thick unit that can be followed for at least 10 km in the vicinity of Alcobaca (Estremadura). Corals, coralline sponges (mainly Calcarea), cryptalgal crusts and, to a lesser extent, crinoids are the dominant constituents of the autochthonous community relic which can be grouped in framebuilders, framework encrusters, frame binders, reef-dwellers, and reef destroyers. These organisms formed low meadows in a shallow, fully marine environment subject to low rates of sedimentation and moderate to low energy levels punctuated by rare high energy events. The abundance of coralline sponges in reefs and reef-like communities is uncommon in the Jurassic and appears to be restricted to very shallow water environments.

It is only the ethological approach, including the evaluation of morphological features according to their significance, which leads to a workable system in ichnosystematics. Based on this concept, the ichnogenusRhizocorallicum Zenker, 1836 can be divided into three ichnospecies:Rh. jenense represents more or less straight, short and commonly oblique spreiten-burrows and can be interpreted as domichnia of a suspension-feeder;Rh. irregulare represents long, sinuous, branching and planispiral forms, andRh. uliarense trochospiral spreitenburrows. The latter two are interpreted as fodinichnia of a deposit-feeder.

The late Jurassic exogyrine oysterNanogyra virgula occurs in fine-grained low-energy sediments of the European epicontinental sea. It is interpreted as having lived cemented to hard substrates during early juvenile stages, but commonly reclining on soft, muddy substrates in the adult stage. This is supported by several morphological adaptations to such a mode of life.