Like other castes they are pale in color and don't have eyes, ears and nostrils like most of the species. The only cast that do have those features is the Familiars or Black Hat. But they have eye sockets stating they used to have eyes before evolving underground. And they have a human like skull which probably means they were probably some form of primate before evolving underground.
As they get older they turn into hive gaurdians and then turn into queens, but only if the current queen is deceased. They can also glide and jump high like most cast.