Hi,I want to ask something.this times it's about tuatara.i know people usually referred it to living fossil since its order(rhynchocephalia if i recall correctly,isn't it?) only have tuatara as its only living representative..but what charateristic make it differ to similar looking lizard?is it a diapsid or anapsid?is tuatara related to archosaur like crocodiles do?thanks

Sorry, slow to the party here. Yes, rhynchocephalians including the extant tuatara are diapsids. Specifically, they are lepidosaurs, which means they are closely related to lizards and snakes -- more closely than to crocs or turtles.