Austroptyctodus gardineri is a small ptyctodontid placoderm fish from the Upper Devonian Gogo Formation of Western Australia. First described by Miles & Young (1977)[1] as a new species of the German genus Ctenurella. Long (1997)[2] redescribed the German material and found major differences in the skull roof pattern so assigned it to a new genus, Austroptyctodus. This genus lacks spinal plates and has Ptyctodus-like toothplates.
The most significant discovery about Austroptyctodus is that one specimen depicts a female pregnant with 3 unborn embryos inside her, showing that like Materpiscis, also from Gogo, this genus was a live bearer that reproduced through internal fertilization.[3]
Austroptyctodus fossil individuals have ostracods recovered in the abdominal region. These ostracods were related to nocturnal ones, suggesting it hunted at night.[4]