found your question while looking for a name for the first all Black Butterflys we had ever seen. On Saturday 31st August 2019 while out walking our dog at the lake in Warminster, my wife and I were astonished to see a totally black butterfly we had never seen one before. It fluttered around quite close to us for two or three minutes and we could clearly see that it was jet black with no other markings at all. Just to put the icing on the cake it was joined by another one and the pair flew off together.