Paradoxides paradoxissimus could probably swim, but it is mostly found associated with benthic faunas of the outer shelf. 

We do not know what Paradoxides paradoxissimus fed on, but it may have been predatory and/or a scavenger.  

Most trilobites could protect themselves by rolling up like an armadillo, but Paradoxides was not well adapted to do this, and may have relied on its size for defence.