I would say that although there is a general accepted look for many of the regions, they are not absolute and variations are common. One such variation for Chiapas is a white dress with the stitched floral designs, not a common as the black. There are many other indigenous costumes, as well, that some groups utilized that may not be immediately recognizable for the region to some in the viewing audience. Guess it would depend how in tune you are with the region and its costuming. Oftentimes, I have had to ask what region a group is dancing, especially when they don't use the common dress.
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