Brindabellaspis
Brindabellaspis stensioi is a flat-snouted placoderm with a platypus-like snout from the Early Devonian of the Taemas-Wee Jasper reef in Australia. When it was first discovered in 1980, it was originally regarded as a Weejasperaspid acanthothoracid due to anatomical similarities with the other species found at the reef.
According to Philippe Janvier, anatomical similarities of B. stensioi's brain and braincase with those of jawless fish, such as the Osteostraci and the Galeaspida, strongly suggest that B. stensioi is a basal placoderm closest to the ancestral placoderm.
