subgeneric names, at least as used in vertebrates, are really units
differentiated from each other.  We look at all the species in a genus and
say, there are two groups of species here which are more like each other than
species in the other group, so I'll call them subgenera.

With superspecies (or metaspecies) my impression is that we look at a given
species and say, "this species is really a group of several very closely
related species which we didn't recognize before" so we call it a
superspecies.

An example.  We usually give domesticated animals a different specific name
than we do their wild ancestors.  This is just a convention, started earlier
but codified by Linnaeus.  Now with the dog, we have since learned that dogs
were domesticated at least 3 and perhaps 4 times from the wolf ancestor, in
different parts of the world.  What do we do now?  Is each of them a
different species?  Or is the whole wolf-dog complex a
superspecies/metaspecies?  Biologically, I think calling them all Canis lupus
makes the most sense, but in terms of practicality, I'm sure we will retain
Canis familiaris for all the seperate origination events.

Is that perfectly murky?