The Coppery-headed Emerald is one of the few species of birds that are true endemics of Costa Rica, meaning only found in this country. The male is mostly green, with the copper hues on the head that can only be seen in the appropriate light and angle. The female has grey underparts and lacks the copper colors on the head. Both have a black downcurved bill, which help with identification versus similar species like the Rufous-tailed Hummingbird, with which it shares the brownish-red rump. They are one of the tiniest species of hummingbirds in Costa Rica. They are seen in the mid to high elevations, in places where there is high humidity, but specially in the Cinchona and Vara Blanca zone.
The Steely-vented Hummingbird belongs to the Amazilia genus, which contains a lot of similar hummingbird species like the Rufous-tailed and the Andean Emerald. They are all very similar in terms of body shape and size, but differ in their coloration and some of them in their habitat and behavior. It has a metallic green body with blue wings and tail, and shows yellow to magenta feathers on the rump. Their bill is thin and straight, and it has white feathers covering its legs. Like the Rufous-tailed, it is very aggressive and territorial.