I'm going to guess some type of Euphonia. I've seen several species on the Osa Peninsula in southern Costa Rica but I don't know if I'd be able to make a confident ID even with a book in front of me. The females / young males can be really tough.
Not necessary Paul. The tanagers are a taxonomic mess and my head is back in the days when Euphonias were in the tanager family. I think they still are considered tanagers for the upcoming Handbook of the Birds of the World but other sources have them with the Fringillid finches.
As for the Yellow-breasted Chat, it's still considered a New World (wood) warbler, for now at least. Several DNA, protein and molecular studies place the species with the wood warblers, but apparently it is lacking a particular small muscle in the jaw, which places the bird closer to the tanagers.
I must say I am fascinated with all this topic because ultimately the classification system we use should reflect the evolutionary history of birds.
jim
If it has a short, stubby tail and below 1200m, then probably female yellow crowned euphonia or thick billed euphonia (females virtually identical except for bill shape and both found near Panama). Lack of white belly rules out female yellow throated and white vented eupnonias which can also be found near Panama. If it has a longer tail might be female summer tanager or hepatic tanager (but they're supposed to be rare near Panama)
Last edited by Peter Hawrylyshyn; 04-08-2011 at 09:16 PM.