Giant temnospondyl amphibians from the Early to Middle Triassic Narrabeen Group of the Sydney Basin, New South Wales, Australia

Material of giant temnospondyl amphibians is described from two localities in the Early to Middle Triassic Narrabeen Group of the Sydney Basin, Austra lia. The capitosaurid Bulgosuchus gargantua gen, et. sp. nov. from the Bulg e Sandstone (Scythian) at Longreef, represented by an incomplete mandible a nd a femur, is the largest known Early Triassic temnospondyl and the earlie st occurrence of a temnospondyl in the Sydney Basin Triassic. B. gargantua is phenetically most similar to Paracyclotosaurus and to 'P'. gunganj, but also shows affinities with Eryosuchus and Middle Triassic species of 'Parot osuchus'. An anterior portion of a large mandible from the Terrigal Formati on (late Scythian-early Anisian) at Bouddi is also described and tentativel y referred to the Capitosauridae, but is generically indeterminate. The mor phology of the post-glenoid area in members of the Capitosauridae is descri bed, and derived characters of the capitosaurid mandible are provided.