The British Racing Green (non-metallic) was offered as one of the standard colors beginning with the 2006 model year. The Lotus Racing Green was a metallic color, and I believe it was first available on the 2005 car. Sounds like what you have is the metallic version....
And of course the totally useless piece of trivia is that there is no such thing as one, true 'British Racing Green.' Lotus has a color called British Racing Green, but that's just what they call it.
Green was the color assigned to British cars for F1 and other racing way back before sponsor liveries (blue was for the US, I believe). BRM, Lotus, and Cooper, Aston Martin, Lola, et al all used different greens, and all were 'British Racing Green.'
Oh yeah, except for privateers who ran their own colors, we can thank Lotus and Sir Chapman for all the gaudy sponsor liveries. He started the trend with the Gold Leaf Lotus'.