Discovery of 30-min oscillations in the Ap Sr(EuCr) star HD 75425

The Ap Sr(CrEu) star HD 75425 is shown to be pulsating with a 30-min period . This is unusually short for a delta Scuti star and about double the perio d of any known roAp star. The star is shown to be constant at the level of 0.35 mmag in the normal frequency regime of roAp pulsation (900 less than o r equal to nu less than or equal to 2500 mu Hz). The pulsations in HD 75425 are modulated in amplitude, but the frequencies causing this modulation ca nnot be identified with the data in hand. HD 75425 is a very close visual d ouble with an insecure Ap classification which needs to be reexamined. If t he Ap classification of HD 75425 is correct, and the pulsations can be link ed to the peculiar star, then this delta Scuti-like variability is of consi derable interest.