Most cultivars I've seen from C.Annuum var. Glabriusculum (The "Tepin" family) start green, then the most sunned parts will get black before the whole pepper turns red. I am growing a variety from a gentleman here on THP called Tio, which I guess mean's "Uncle" in Peruvian Spanish. They do that same thing, and actually look quite similar to the ones in your picture, except the leaves look different.