Ferrari has unveiled an exotic convertible that incorporates a new kind of retractable hard top. It takes an old Ferrari name — the Superamerica — and brings Ferrari back together with one of the most famous designers in its history.

As design chief of the Pininfarina studio in the 1960s and 1970s, Leonardo Fioravanti shaped a number of Ferrari’s classic models, including the Daytona, Boxer and 308GTB. Now, as an independent design consultant, Fioravanti has developed and patented a unique rotating car roof that flips back in one piece and sits neatly above the boot lid, forming an effective wind deflector when it is open.

Not only is the revolutionary rotating roof electrically operated, it is made from special electrochromic glass that has five levels of transparency (shading) selected from a dashboard control. It changes between the extremes of light and dark in less than a minute.

The Superamerica convertible is a limited-edition version of the 575M Maranello with the power output of its 5.7 litre V12 engine increased from 515 to 540bhp. Ferrari quotes its maximum speed as 199mph.

The price of this limited-edition model — no more than 500 will be made — has not yet been set, but apart from its rotating glass roof it has all the expensive extra features that are available for the 575M, including the GTC handling package and carbon-ceramic brakes, so it will cost significantly more than the £156,700 of the standard coupé.

Previous Superamerica models from the 1960s had the largest Ferrari engines of the day, were made in very small numbers and are now highly valued by collectors.