The last one. I hope I'll see it some day before its too late. There will probably not be any more in captivity outside Africa.
I saw it last month and am so delighted. If I were you, I'd organise a trip to Brownsville as soon as possible. I understand this antelope is around 13 years old and an experienced ungulate keeper told me that is very high for a duiker. I'm not even sure if there are any in captivity in Liberia, but I know many are being killed and eaten by militants in the never-ending civil war down there.