Xeradipterus hatcheri, a new Dipnoan from the late devonian (Frasnian) gogo formation, Western Australia, and other New holodontid material

摘要

A new holodontid lungfish, Xeradipterus hatcheri, gen. et sp. nov., is described from the Late Devonian (Frasnian) Gogo Formation, Western Australia. The material comprises a single specimen preserved in a large concretion, represented by elements of the skull roof, cheek, lower jaw, palate, shoulder girdle, and parts of the postcranial skeleton. Xeradipterus, gen. nov., differs from other holodontids by its broad crushing dentition, prearticular tooth plates with pronounced heel, lack of prominent teeth, and ordered tooth rows, and by its parasphenoid morphology. Results of PAUP analyses of 82 characters for 33 dipnoan taxa revealed that the new genus is a member of the Holodontidae, suggesting a possible endemic radiation of holodontids within the Gogo fauna. In addition, new "Holodipterus" elderae material examined shows the shape and extent of the nasal capsules, and the presence of an anterior median callus for the first time.