There are over 33 spices of trapdoor spiders. One of my favorite trapdoor spiders is the ravine trapdoor spider (below). It's abdomen is different from all spiders. The back part is flat and it has a weird pattern on it. Instead of having a lid on their burrow their abdomen is their replacement.
Another kind of trapdoor spiders is the migidae (below). The name migidae is a scientific name. There's spiders are the same as regular trapdoor spiders but they are smaller and make their burrows on/in trees. Also they are less common.
A common trapdoor spider is the African red trapdoor spider (below).
There are many more species of trapdoor spiders