The Lesser Greenlet, Hylophilus decurtatus, is a small passerine

Passerine

A passerine is a bird of the order Passeriformes, which includes more than half of all bird species. Sometimes known as perching birds or, less accurately, as songbirds, the passerines form one of the most diverse terrestrial vertebrate orders: with over 5,000 identified species, it has roughly...

 bird

Bird

Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...

 in the vireo

Vireo

The vireos are a group of small to medium-sized passerine birds restricted to the New World. They are typically dull-plumaged and greenish in color, the smaller species resembling wood warblers apart from their heavier bills...

 family. It breeds from northeastern Mexico

Mexico

The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...

 south to western Ecuador

Ecuador

Ecuador , officially the Republic of Ecuador is a representative democratic republic in South America, bordered by Colombia on the north, Peru on the east and south, and by the Pacific Ocean to the west. It is one of only two countries in South America, along with Chile, that do not have a border...

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This is a common species of lowlands and foothills up to 1200 m altitude, where it inhabits forest canopy and edges, and the crowns of trees in tall second growth or semi-open areas. The nest is a deep cup of dead leaves and spiderwebs attached by the rim to branches 10–15 m high in a tree. The normal clutch is two brown-marked white eggs.

The adult Lesser Greenlet is 10 cm in length and weighs 9 g. It has olive-green upperparts and a pale grey head with a white eyering. The underparts are white with a yellow tinge to the breast and some olive on the flanks. Young birds are duller and brown above, and have a buff tone to the sides of the head and the breast.

There are two races. Nominate H. d. decurtatus which breeds from central Panama

Panama

Panama , officially the Republic of Panama , is the southernmost country of Central America. Situated on the isthmus connecting North and South America, it is bordered by Costa Rica to the northwest, Colombia to the southeast, the Caribbean Sea to the north and the Pacific Ocean to the south. The...

 southwards has a green crown to the head, and grey-crowned H. d. minor occupies the northern part of the bird’s range. The latter subspecies was formerly given species status as the Grey-crowned Greenlet, H. minor but the two forms interbreed extensively in central Panama and are now considered to be conspecific.

Lesser Greenlets feed on spider

Spider

Spiders are air-breathing arthropods that have eight legs, and chelicerae with fangs that inject venom. They are the largest order of arachnids and rank seventh in total species diversity among all other groups of organisms...

s and insect

Insect

Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...

s gleaned

Gleaning (birds)

Gleaning is a term for a feeding strategy by birds in which they catch invertebrate prey, mainly arthropods, by plucking them from foliage or the ground, from crevices such as rock faces and under the eaves of houses, or even, as in the case of ticks and lice, from living animals. This behavior is...

 from tree foliage, They also eat small fruits and seeds. They will join mixed-species feeding flock

Mixed-species feeding flock

A mixed-species feeding flock, also termed a mixed-species foraging flock, mixed hunting party or informally bird wave, is a flock of usually insectivorous birds of different species, that join each other and move together while foraging...

s, and often accompany gnatcatcher

Gnatcatcher

The 15-20 species of small passerine birds in the gnatcatcher family occur in North and South America . Most species of this mainly tropical and subtropical group are resident, but the Blue-gray Gnatcatcher of the USA and southern Canada migrates south in winter...

s, warblers

New World warbler

The New World warblers or wood-warblers are a group of small, often colorful, passerine birds restricted to the New World. They are not related to the Old World warblers or the Australian warblers....

 and honeycreeper

Honeycreeper

The typical honeycreepers are small birds in the tanager family. They are found in the tropical New World from Mexico south to Brazil.They occur in the forest canopy, and, as the name implies, they are specialist nectar feeders with long curved bills....

s.

The Lesser Greenlet has a nasal neeah-neeah-neeah-neeah call and the song is a whistled chi chi cher cher cher cher chiri cher which cheri, slower and more melodious than that of the Yellow-green Vireo

Yellow-green Vireo

The Yellow-green Vireo, Vireo flavoviridis, is a small passerine bird. It breeds from southern Texas in the United States and the western and eastern mountain ranges of northern Mexico south to central Panama...

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