Strata of Jurassic age occur extensively across onshore Australia, but they are predominantly of non-marine origin. Marine Jurassic strata have only limited onshore exposure in northwestern and central-western Australia, with thick marine sequences lying offshore on the North West Shelf. The richest petroleum province in Australia is located at the shelf's southern end, where the Dingo Claystone represents an important source rock for oil and gas. By and large, non-marine deposits, including economic coals, are distributed in the eastern states. Jurassic stage boundaries, in the main, are poorly constrained with respect to the Australian sedimentary succession. New work on microfossils, plants, fish, and zircon dating is providing a basis for improved correlation across Australian basins, with overseas successions, and recent international IUGS geologic timescales.

-"Leptolepis" talbragarensis Woodward, 1895, is the most common fish species in the Talbragar Fish Bed near Gulgong, New South Wales. The genus Cavenderichthys Arratia, 1997, has this species as its type. The three species originally proposed by Woodward (1895) for "Leptolepis" are a single species. A detailed comparison of Cavenderichthys talbragarensis with members of the genus Leptolepis, and also with the Late Jurassic forms Tharsis dubius and Leptolepides sprattiformis, indicates that Cavenderichthys talbragarensis is most closely related to Late Jurassic members of the Family Leptolepididae. Analysis of zircons for geochronology showed that the sediment just below the richest fish layer has a youngest component of 151.55 ± 4.27 Ma, corresponding to the Kimmeridgian Stage of the Late Jurassic. Thin sections of the upper prolific fish layer show preservation in tuffaceous sediments, indicating that the fish population was killed by ash falls of felsic tuff that filled the pond they inhabited.

No abstract

Eastern Australia has two major Mesozoic fossil localities. The Talbragar Fish Bed in central west New South Wales contains an assemblage of Upper Jurassic fishes, plants and insects. The Koonwarra Fossil Bed, in South Gippsland, Victoria, has an assemblage of Lower Cretaceous fishes, plants and insects. The geological settings of these localities are described. Each locality has a common genus of fish that was originally described as Leptolepis. The names of both these fish have been changed, the Talbragar one to Cavenderichthys talbragarensis and the Koonwarra one to Waldmanichthys koonwarri. Both of these fish have been placed into the Family Luisiellidae, together with a Patagonian fish, Luisiella feruglioi. Each locality also has a member of the family Archaeomenidae: Archaeomene tenuis from Talbragar and Wadeichthys oxyops from Koonwarra. The relationships of these and other fish have been discussed by various authors over the last 20 years and a summary of these comments is presented, as well as a brief comparison between the plants of both localities. The localities of Talbragar, Koonwarra and the Argentinian fishes during the Mesozoic appear to have similar palaeo-environmental settings, which may explain the similarities in the assemblages. The Australian localities contain well-preserved specimens which shed light on the diversity and extent of fishes in southern Gondwana, a region otherwise poorly represented in the fossil record.

No abstract