There's nothing like a lime green Jaguar XKR to pierce the UK's gray landscape. Our English spy caught a image under test, sporting all of the cues found on Jag's "Goodwood Special" XKR, that showed up at this year's Goodwood Festival of Speed. In addition to the lime green paint, the special Jag gets low-key graphite-colored trim where bright chrome would usually reside.

The car running at Goodwood was plated only with PR-spec XKR license plates, but this car is officially registered in the UK as a prototype. The only other difference between the promotional vehicle and the vehicle caught under test here is the omission of the original car's grey-and-orange XKR decals. Perhaps they were deemed a little over-the-top.

This image shares the original's 21-inch alloys, lowered suspension, and more aggressive exhaust tuning. It also likely shares its engine mods, which reportedly bumped-up the output  20 horses to 530hp, along with an increase in torque from 461 lb-ft to about 515 lb-ft. When the eye-singeing XKR was originally presented at Goodwood, Jag officials said it was a one-off model, but could attain limited-run position if demand warranted.

This prototype's appearance on Jaguar's normal test routes suggests that the Goodwood Special may be destined for showrooms after all.