This bird is know is the twa twa by the Trinidadians and most of the south of America. There is a miss-communication that exist between Trinidadians and Guyana's residents with the name of this bird. I spoke to a intermediate bird salesman about the Bullfinch and he told me that they call it a twa twa. For the Tini the twa twa is the bird you see on the left. This bird as you can see is all black except for its distinctive white wing patches and its silver beak. This bird I have little knowledge about because I was unable to observe them  in the wild. I saw a few in the local pet shops and I was unable to get any real information about the birds and their habitat. You might be able to find more information on this bird from Arthur Grosset's website which is a compilation of South American Birds.