This seems a bit out of context.... Are these pics from the wild (and if they are, where?) or are they from captive animals? Except for the last, which looks like Cryptophyllobates (Epiped.) azurieventris, they are all thumbnails.... of forms rare/advanced if at all present in the US hobby.
My guess on the first might be D. imitator yurisomethingorother but can you really tell without seeing the color of the tad or knowing its call/behavior? The second and third looks like lamasi panguana.