Mercedes-Benz has patented the design of a new concept version of daughter company Smart’s Fortwo city car, set to be called Speedster and also set to launch at the Geneva motor show in March.

The ultra compact open top recalls the earlier limited edition Smart CrossBlade by featuring a cut down windscreen and no apparent provision for a roof of any kind.

See the patent pics of the new Smart Speedster concept

The Speedster is a pure concept, however, and is not said to inspire any future production car, but it will share its all-electric E-drive drivetrain with the Smart E-cell.

While appearing to retain similar dimensions to today’s 2695mm long and 1560mm wide Fortwo, the Speedster depicted in Mercedes-Benz’s latest computer generated patent images looks to have gained wider tracks front and rear, giving it a more confident stance.

Read more on the future of Smart

The puristic two-seater also receives a series of new design details, including a larger grille, rounded head and tail lamps, altered surfacing treatment as well as distinctive step in the waistline. The Speedster look is further enhanced by twin roll over hoops integrated into the Smart’s exposed steel safety cell.

A third-generation Fortwo line-up is being developed by Mercedes in partnership with Renault, the initial coupe and cabriolet versions of which are due to go on sale in 2012.

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