Woodnymphs are hummingbirds in the genus Thalurania. Males are green and violet-blue, while females are green with white-tipped tails and at least partially whitish underparts. Both sexes have an almost straight, entirely black bill and little or no white post-ocular spot. They are found in forest (primarily humid) and tall second growth. The species in this genus are almost entirely allo- or parapatric, and a species is present virtually everywhere in the tropical humid Neotropics.