Ruddy Treerunner

The ruddy treerunner (Margarornis rubiginosus) is a passerine bird in the Furnariinae subfamily of the ovenbird family Furnariidae. It is found in Costa Rica and Panama. == Taxonomy and systematics == The ruddy treerunner has two subspecies, the nominate M. r. rubiginosus (Lawrence, 1865) and M. r. boultoni (Griscom, 1924). == Description == The ruddy treerunner is 15 to 16 cm (5.9 to 6.3 in) long and weighs 17 to 24 g (0.60 to 0.85 oz). The sexes have the same plumage. Adults of the nominate subspecies have a buffy whitish supercilium and eyering on an otherwise dull rufescent brown face. Their crown is dull reddish brown and they have a narrow, paler reddish, collar. Their upperparts and wing coverts are reddish chestnut. Their flight feathers are dark fuscous with rufescent edges. Their tail is a slightly paler reddish chestnut than the back; the ends of the tail feathers lack barbs, giving a spiny appearance. Their throat is whitish with a buffy white lower edge. Their breast is dull rufescent brown with pale buff "Vees" on its upper part and darker buff spots on the lower. Their belly is almost unmarked dull rufescent brown and their flanks and undertail coverts…