Vexillum citrina (Gmelin, 1791) and regina (Sowerby 1828) should be
synonimous; filiareginae Cate is an "orange and white banded" form, while
compressa (Sowerby, 1874) for Tucker & Dance is again a synonimous, and for
Springsteen & Leobrera a form; taeniatum Lam. (syn.: vittata Swainson ) is
another species.
All these shells are very variable in colour and form: for instance I have
both filiareginae and regina (so identified) but for me are respectively
regina and coccineum!
Good luck :-)
Sandro