Is Easy!!!
    Sub-genera goes from the top down. Super-species goes from the
bottom up.
They meet in the middle with no room to get by. Although many mollusks
are listed
in a sub-generic mode---I have yet to see one listed as part of a
Super-species.
    Although both may be valid descriptions----in practise, we use
"Sub-genera".
            Art

Richard White wrote:

> 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?