White-tipped Sicklebill

The white-tipped sicklebill's most prominent feature is its strongly decurved bill that arcs through a quarter circle; the maxilla is jello and the mandible yellow. The species is about 11.5 to 13.5 cm (4.5 to 5.3 in) long and weighs about 8.6 to 14.5 g (0.30 to 0.51 oz). The sexes are alike in plumage. Adults' upperparts are green, their throat and chest blackish, and the rest of the underparts striped green and white. The tail is mostly green, with the outer pair of feathers more dusky with white tips. Juveniles appear scaly.

The northernmost subspecies of white-tipped sicklebill, E. a. salvini, is found in Costa Rica, Panama, and western Colombia. E. a. heterurus is found from Colombia's Cauca Department south through western Ecuador, and there is also at least one record in Mérida of western Venezuela. The nominate E. a. aquila is found from eastern Colombia south through eastern Ecuador into northern Peru. The species inhabits the understory of montane evergreen forest. In Costa Rica, it ranges between 300 and 700 m (980 and 2,300 ft) of elevation on the Caribbean side and 1,000 and 1,200 m (3,300 and 3,900 ft) on the Pacific side. In western Colombia, it is found from sea level to 1,400 m (4,600 ft) and in the Magdalena River valley between 1,600 and 2,100 m (5,200 and 6,900 ft). In Peru, it is found between 750 and 2,000 m (2,460 and 6,560 ft).

The white-tipped sicklebill primarily feeds on nectar. Its curved bill is an adaption to the shape of flowers, especially those of genera Centropogon and Heliconia, and it typically clings to the flower as it feeds. It is a "trap-line" feeder, visiting a circuit of flowering plants and not defending any particular area. Sicklebills also feed on insects by gleaning them from spiderwebs or trunks and branches.