Er, that's "Fossilsaurus".Credit (or infamy depending) where it's due, but I believe it was someone sitting around Bandai that snapped their fingers first. Which is also probably why Hasbro won't make just straight "rocks".
On a side note - this is their chance to fix the biggest missed opportunity of the Fossilizers subline by giving us a Transformers version of "Rockasaurus Rex"!