Macnamaraspis Kaprios (The Gogo Fish) is an extinct placoderm of the Late Devonian period that inhabited the ancient reef system of north Western Australia.  It grew up to 500 mm in length and with its large eyes, articulated jaw and razored dentition plates the Gogo Fish would have been a formidable predator.

Gogo Fish is a member of the order Arthrodira, meaning ‘jointed neck’, and like other placoderms in that order, it would have been able to attack and eat creatures that were not very much smaller than itself.

It has been speculated that the armoured bite of the more predatory placoderms evolved as an effective means of cracking through the shelled defences of the plentiful arthropods. It has been noted that at around the same period trilobites began to appear with a profusion of spines, possibly as a counter defence to the predatory placoderms.

Remarkably intact fossil specimens of the Gogo Fish, along with other placoderms, have been discovered in the Gogo formation of Western Australia (once an ancient inland sea). Fossil remains are typically flattened in form due to geological pressure over time but the Gogo remains were uniquely encased within limestone nodules.  After careful dissolving of the surrounding limestone fully intact specimens have emerged.  This has allowed for a much greater understanding of the anatomical structure of placoderms.

Gog Fish Mcnamaraspis anatomy from Paleozoo Evolutionary Models by Bruce Currie

The Gogo Fish displayed a new anatomical feature - a distinctive cartilaginous snout. It became the state fossil of Western Australia in 1995.

Paleozoo replicas are museum grade models, based on accurate data. They are available for sale here via the store link below.

With thanks to Prof John Long for assistance with anatomical detail.