Apart from the mongoDB instances, there are some other nodes listed in the list view. What are those nodes?

Apart from the mongoDB instances, there are some other nodes listed in the list view. What are those nodes?

Reason: They are dummy nodes added to group the mongoDB servers in a replicaSet.  These are used to show the parent child hierarchical view in monitor snapshot page. They will be deleted automatically when all the replicaSet nodes are deleted. They do not have any other significance and can be ignored.