WRL import and subsequent modification (Indexed Face Set)

I tried very hard to solve this issue with manuals and Google questions, but I got stuck:

I import a wrl file and Blender shows me a “Shape_IndexedFaceSet” object. Now I would like to work with this, e.g. separate the loose parts and rig them individually. If I go to Mesh-Vertices-Separate-By loose parts, every single faces becomes an individual object.
Is there any way how to separate the obviously loose parts of an imported WRL file without creating thousands of faces as single objects?

Sooo many thanks upfront,