It's not too unusual to think that China never developed a "Ground Fighting" system.

Pre-Gunpower history the Greeks and the Japanese (since the Romans got their ground fighting from the Greeks) are really the only two cultures to develop a ground game. Other grappling systems around the world, from Mongolian, Middle Eastern, Celtic, Norse, Mayan, African, Chinese, etc..... were standing grapling arts that had throws, occasional chokes/ locks and ground and pound type tech. No high level Submission grapling even existed in the rest of the world.

Most ground fighting systems that we know of today are modern systems that actaully borrowed and evolved their techniques from the Greek and Japanese systems (aka: Sambo, Modern Greco-Roman Wressling and BJJ)

And I think eventually we will see influance from these other arts start to filter into CMA