For a while now we've been waiting for the Land Rover Defender replacement test mule to spotted and thankfully, one eagle eyed photographer has done so!

Development mules are used as a testing bed for new vehicle models, allowing manufacturers to test components and evaluate designs on real roads. Usually they carry heavy camouflage and production parts will be shrink-wrapped to disguise styling cues.

For those thinking, it looks just like a chopped down Range Rover Sport. Well, that's exactly what it is. The design engineers have taken a Range Rover Sport and hacked it up. It's what's underneath that's important.

Behind all that chop shop styling is likely the underpinnings of the new Defender. We know that these prototypes have existed at last since October 2016, as JLR Chief Ralf Speth told the automotive press that he had driven test models at that stage. They have been registered for road use since September 2017.

Short Wheel Base

The front end appears to be visually similar to the Range Rover Sport, although the overhang could well be shorter. That would make sense if this were a Defender underneath.

The wheelbase is the biggest giveaway that this is a Defender development mule, it's too short to be anything else. It definitely looks to be close to the old model's 92.9 inch wheel base.

That blanking material at the front is possibly hiding a nearly finished grill design. Note the Range Rover Sport doesn't have that black block on the leading edge of the bonnet.

The awkward step in the roof line makes this look like a real bodge job. But the test body is only there to hide what's underneath.

Predictably, the new Defender will sport independent suspension and gone are the live axles of old. Ground clearance looks reasonable.

That towing bracket is different to any fitted to Range Rovers and the rear body is much higher than a production RRS. There's minimal body overhang.

A quick check of this vehicle's registration reveals it to be listed as:

Land Rover - White.

That's all!

The test mule has quite a rakish lean. The wheel well at the rear is misshapen too, likely as a result from the cutting down of the body. Those wheels look oddly familiar.

Almost straight off the DC100!

Long Wheel Base

Additional images are surfacing of a LWB model too.

This registration is listed only as a "Black Land Rover". It was registered in September 2017. The emissions are listed as Nil, is this an electric vehicle?

That plastic trim running along the bottom and the exaggerated hips around the wheels looks very reminiscent of the DC100.

What can we learn from this prototype Defender?

There's probably a chassis (frame) under there. It wouldn't be simple to cut down the Range Rover body like that without sitting it onto a chassis of some sorts.

Is it electric?

DVLA held information for both these vehicles lists the emissions as 0g/km CO₂. The Cylinder capacity is listed as not available. Are they electric? If so, the exhaust is there only as a decoy!

This is exciting stuff! We can't wait to see more!