Dear Jenny,
it's not so rare to find hybrids in Cypraea.
Most of them are for instance between annulus and moneta, but I suppose that
is because they are very common and the probability to find an hybrid is
greater. Note that also your "has a part" of moneta.
Recently a friend of mine (are you listening, Luciano?) has found an
intermediate form between annulus (again!) and obvelata.
Sandro
PS: can also I receive a picture?