Pterichthyodes was one of a number of
heavily armoured fish called antiarchs,
which were a subgroup of the early fish
group called placoderms. Its entire head and
body were encased by large armoured plates
as a formidable defence against predation.
This fish was benthic - a bottom-dweller -
as shown by the eyes, which are located on
top of the head rather than to the sides.
The mouth acted as a shovel to churn up the
sediment in search of small prey. Placoderms
evolved rapidly in the Devonian to become
the dominant vertebrate predators. Some
were giants, with the Late Devonian
Dunkleosteus growing to more than
6rn120ft long - the largest predator of
its time, However, they had died out
, 'by the Early Carboniferous Period.