The books say Gray-headed Tanager is pretty dependent upon antswarms too, but I've seen this bird away from ants more than I've had them with them.
Spotted Antbirds dominated this little group. They would perch low and then flash into the gloom before frequently returning flycatcher-style back to the same perch. This is a male and a female.
The star of this little flock was a Black-faced Antthrush. I saw my first one in Belize, walking across a fairly open forest floor. I had no idea how uncommon that is, every one since was moving more rapidly in much denser thickets. This one foraged like a sanderling, jogging about and abruptly changing direction when it spotted a prey time.