A new species of dipnoan, Chirodipterus potteri, is described, based on a series of juvenile tooth plates with attached bone from two localities in New South Wales, Australia. Most of the material comes from the Upper Devonian (Fammenian) Coffee Hill Member of the Catombal Range, west of Orange, and some from the Upper Devonian (Frasnian) Paling Yard Formation, at Gap Creek. The new taxon provides additional insights into the fine structure and the development of chirodipterid tooth plates, and includes some anomalous specimens. Tooth plates are based on a form of interdenteonal dentine with irregular denteons containing circumpulpar dentine, surrounded by mantle dentine and enamel, and ankylosed to the underlying jaw bones. Analysis of the material indicates that the tooth plates of chirodipterid lungfish are not members of the dentine plated clade, but have tooth plates that are based, as in most other dipnoan species, on the fusion of radiating rows of initially separate cusps in the young juvenile to form a crushing or grinding structure in the adult.