It may look like the current Mustang...but it's a "mule" helping develop the next-gen pony car - and a long-rumored Lincoln coupe spin-off.

At first glance, this Mustang looks completely familiar. Well, not completely. Take a closer look and you’ll soon realize it has been somewhat altered in a number of ways from the pony car in the showroom today.

That makes it clear to our spy shooters that they’ve captured a “mule” being used to test the platform and, very likely, the updated engine that will go into a completely updated version of the Mustang now just a couple years away.

And that means we’re also getting some hints about the planned rear-wheel-drive Lincoln model that Ford CEO Alan Mulally recently acknowledged during an interview with TheDetroitBureau.com is currently under development.

An independent rear suspension is partially hidden here.

So, what should you be looking for with these images? From the front there is little to see that’s different. But that galloping horse set alone in the grille is a design not offered on current Mustang models.

From the side, there are the blacked-out wheels. I counted twenty spokes in these rims, many more than you see on any current Mustang, and a big hint to the car’s true identity. They are the kind of wheels you find on much more expensive cars than the Mustang. Can you say “Lincoln”?

At the rear, some work is evident from the tear-up of the modesty panel. Material is cut away at the sides of the panel near the exhaust pipes and below the bumper line. That’s to make room for the repositioned tailpipes.

The next Mustang is expected to appear in time to mark the pony car's 50th anniversary in mid-2014.

Below all is a silly little receiver that’s usually used for a trailer tow bar. Here, it’s used as a disguise to hide the new independent rear suspension that Ford is planning for the 2015 Mustang (and that Lincoln coupe).

Still doubt the purpose of this vehicle? Check out the M-plate at the rear and the PITOT tube on the roof. Pure test vehicle.

The next Ford Mustang is likely to be launched in mid-2014 and while it would normally be declared a 2015 , the maker is reportedly planning to label it a 2014-1/2 to honor the original mid-model-year designation of the very first Mustang — which will be celebrating its 50th anniversary.