White-fringed or Black-bellied Antwrens? Canudos, Brazil (1 Viewer)

I recently photographed this antwren at Canudos, the Lear's Macaw site in North-east Brazil. I am tending more towards it being a Black-bellied Antwren, but I am still unsure. Black-bellied should have a thicker white supercilium, especially behind the eye, which this bird has, and less white on the flanks than White-fringed. However, although it looks quite clear in the books, it is not as straightforward when looking at photos online. This is not made easier by the fact that the White-fringed has been split by some authorities into a northern and southern version (Canudos would be the southern form).
If anyone has experience with either species, I would appreciate some input. I don't have any better photos, though I do have lots more from different angles as it moved through the undergrowth, if there are any particulate features needed to help the ID.
Thanks,

Tom

I think it looks okay for Black-bellied Antwren, which would be the more expected species at Canudos too. Some good features include the black throat meeting the brown mantle and cutting off the white supercillium. Also the white tertial edges and white lower edge to the scapulars are better for Black-bellied.

Very helpful explanation of these ID features. Thanks Andrew.

Tom