Sydney Basin in the Triassic—A review of the geology, flora and fauna, and ecosystems. The Hawkesbury Sandstone

The Australian Museum has a large palaeontological collection of Triassic specimens from the Sydney Basin, including many type specimens. This study reviewed every presently described Sydney Basin Hawkesbury Sandstone plant and animal taxon that has representative specimens held in the Australian Museum. Fifty-two taxa are included from numerous sites. These include three amphibians, twenty-eight fishes, eleven insects, one horseshoe “crab”, one scorpion, three crustaceans, two molluscs and three plants. Basic taxonomic history is noted, together with specimen registration numbers and their position in the collection. Also included are references to relevant specimens held in the Geological Survey of New South Wales and the Natural History Museum, London collections. Images of every taxon are included. To place the collection in context, particularly for educators working with students, brief descriptions of the geology that forms the Hawkesbury Sandstone, and the inferred ecosystems that existed during the Middle Triassic, are included. The results of this study will help to facilitate further researchers by providing important details of the fossil collections held at the Australian Museum.