Abstract

Remote Devonian exposures in central Australia have produced significant but highly fragmentary remains of fish-grade tetrapodomorphs. We describe a new tetrapodomorph from the Middle-Late Devonian (Givetian-Frasnian) Harajica Sandstone member of the Amadeus Basin, Northern Territory, which is represented by several nearly complete skulls along with much of the body and postcranial skeleton. A phylogenetic analysis resolves the new taxon as the basal-most representative of the Canowindridae, a clade restricted to the Middle-Late Devonian of Australia and Antarctica. The new form has large spiracular openings, a posteriorly broad postparietal shield, broad, triangular extratemporal bones and a lanceolate parasphenoid. Large spiracular openings are previously unknown in canowindrids, but have been recorded in elpistostegalians and Gogonasus, demonstrating these structures, suggestive of spiracular surface air-breathing, appeared independently in widely differing nodes of the stem-tetrapod radiation.