The Cocos Island Flycatcher are a species of birds endemic to Costa Rica. They average 13 cm long and is listed as Vulnerable on the endangered species list. They have a long bill, greyish-olive to dark brownish-olive backs, dusky wings with two wing-bars and pale greyish-buff to pale yellowish underparts. They live in subtropical or tropical moist lowland forests, subtropical or tropical swamps, subtropical or tropical moist montane forests, and subtropical or tropical moist shrubland. Their diet consists of insects and, and seasonal fruits. Their voice is dry, and their calls are in a descending and accelerating trill. The Cocos Island Flycatcher is the only species in the genus Nesotriccus