The blartworm replaced the cave batworm once they left the confines of the caves to the much more verdant outside world. The heat detector tentacles (known as blarts) have clustered together on the front of the blartworm's face in a sort of mustache. The blartworm is smaller than its ancestor as there are more predators in the outside world and smaller means harder to catch. Their poison has mostly disappeared as it is too draining on the blartworm's resources and they do not really need it. They now group in swarms of around forty individuals, but different swarms often cross paths. Other than these changes and a change in coloration, the blartworm is quite similar to its ancestor.