Greater scythebill

The greater scythebill (Drymotoxeres pucheranii) is a Near Threatened species of suboscine passerine bird in the subfamily Dendrocolaptinae of the ovenbird family Furnariidae. It is found in Colombia, Ecuador, and Peru.

Taxonomy and systematics
The greater scythebill was long included in genus Campylorhamphus with most other scythebills, but the discovery of its closer affinities with the scimitar-billed woodcreeper (Drymornis bridgesii) resulted in the creation of the new genus Drymotoxeres for the greater scythebill. The two are genetically more closely related to each other than to the other scythebills and woodcreers.

The greater scythebill is the only member of its genus and is monotypic: no subspecies are recognized.

Description
The greater scythebill is 24 to 30 cm long and weighs 63 to 78 g. It is the largest and heaviest scythebill with a shorter, stouter, and less curved bill than the others. The sexes have the same plumage. Adults have blackish brown ear coverts, a distinct whitish supercilium, and an even bolder whitish moustachial stripe. Their upperparts are dull rufous brown to chestnut with a darker crown. Their crown and nape have thin buff streaks that sometimes continue onto the upper back. Their rump, wings, and tail are dark rufous-chestnut. Their underparts are rufous-brown to chestnut with grayish streaks on the throat, breast, and sometimes the upper belly. Their iris is dark brown, their bill dull pinkish horn to creamy gray with a blackish base to the culmen, and their legs and feet brownish gray to dark brown. Juveniles are more rufescent than adults with coarser but less well defined streaking above and below.

Distribution and habitat
The greater scythebill is found only locally, in the Andes of central and southwestern Colombia, on the western slope of the Ecuadoran Andes south to Pichincha Province, and all along the eastern slope of the Ecuadoran Andes into Peru as far as the Department of Cuzco. It inhabits humid montane forest in the subtropical to temperate zones. It favors the interior of evergreen forest, cloudforest, and elfin forest; it does occur at the forest edges and occasionally in banana plantations. In elevation it ranges between 900 and 3250 m but most often between 1000 and 3000 m in Colombia and 2000 and 2800 m in Ecuador and Peru.

Movement
The greater scythebill is believed to be a year-round resident throughout its range.

Feeding
The greater scythebill's diet is not known in detail but is believed to be mostly arthropods. It is almost always seen singly and readily joins mixed-species feeding flocks. It typically forages in the forest's lower and middle levels. It hitches up trunks and branches, gleaning prey from the surface and probing into crevices and moss.

Breeding
The greater scythebill's breeding biology is almost unknown. Its breeding season includes October. The one known nest was in a vertical cavity in a living tree and contained two eggs.

Vocalization
The greater scythebill's song is described as an "alternating series of twitters and nasal 'ik' notes" and by another author as "a rather weak and nasal, ascending 'ee-ee-ee-ee-ee-énh' ". It is very different from those of all other scythebills.

Status
The IUCN has assessed the greater scythebill as Near Threatened. It has a limited range and its population size is not known and is believed to be decreasing. "This scarce and poorly known species has a moderately small, fragmented distribution, and is likely to be declining in most areas owing to ongoing habitat loss." The species is "[b]elieved to be highly sensitive to human disturbance in a region where habitat loss is extensive and continuing, if not accelerating."