The 2015 Mazda MX-5 / Alfa Romeo Spider has been spied for the first time. See the pictures inside

The 2015 Mazda MX-5 / Alfa Romeo Spider has been spied for the first time.

Snapped outside Chrysler's Tech Center in Auburn Hills, the mule has a heavily-modified MX-5 body which has been pieced together. While it's certainly not a looker in its current condition, the prototype gives us a rough idea of the roadster's overall dimensions.

The details are hard to make out but we can see an added section in front of the A-pillar which suggests the model will have classic "long hood, short deck" proportions. We can also see longer doors which implies the model has a longer wheelbase. Last but not least, the extended wheel arches suggest the car could have a wider track.

Engine options remain a mystery, but the companies have previously said the "Mazda and Alfa Romeo variants will each be powered by specific proprietary engines unique to each brand." Early speculation suggests the Mazda will use either a 1.3- or 1.6-liter SkyActiv engine, while the Alfa could have a 1.4-liter MultiAir engine with at least 120 HP (89 kW).

The Mazda MX-5 is expected to be launched in 2015 and the Alfa Romeo Spider - which could be called the 2C - is slated to follow shortly thereafter.