Abstract Microvertebrate samples from the Upper Devonian Hojedk section, southeastern Iran, and the Napier Formation, northwestern Australia, have yielded scales of agnathan thelodonts, dated as early/mid-Famennian ( crepida–marginifera/trachytera conodont zones). These scales are referred to Arianalepis megacostata , a new genus and species, and Arianalepis sp. indet., a second indeterminate species of this new turiniid genus. Further recorded scales of Australolepis seddoni from the Napier Formation confirm the age range for this taxon as extending into the late Frasnian. The new remains post-date the previously youngest thelodonts from Iran and Western Australia and provide the first evidence of thelodonts surviving the Frasnian–Famennian extinction events.