Slaty Spinetail
Synallaxis brachyura
The slaty spinetail is 14 to 16 cm (5.5 to 6.3 in) long and weighs 16 to 21 g (0.56 to 0.74 oz). The sexes have the same plumage. Adults of the nominate subspecies S. b. brachyura have a grayish supercilium on an otherwise darker gray face. Their crown and nape are deep rufous-chestnut, their back is dark sooty brown to slate-brown, and their rump and uppertail coverts are slightly browner than the back. Their wing coverts and base of their flight feathers are deep rufous-chestnut and the rest of the flight feathers are dark brown. Voice: The slaty spinetail's song has been described as "ch-ch-ch-churrr-r-r-r", "je-ch-ch-chrrrrr", "chut-chut-chrrrrrrrrrrr", and a wren-like "hard trill". While foraging it gives a "chk" call; another call is "chee-ah".
ID text from Wikipedia, CC BY-SA 4.0

Sooty-fronted Spinetail
Synallaxis frontalis
The sooty-fronted spinetail is 14 to 16 cm (5.5 to 6.3 in) long and weighs 11 to 17 g (0.39 to 0.60 oz). The sexes have the same plumage. Adults have a thin brownish line through the eye on an otherwise brownish gray face. Their forecrown ("front") is dark gray-brown, their hindcrown and nape dark rufous, and their back, rump and uppertail coverts brown with a rufescent tinge. Their wing coverts are dark rufous and their flight feathers tawny-rufous with dusky tips. Voice: What appears to be the sooty-fronted spinetail's song is variously described as " 'ka-kwee-éék', 'ka-kweek', 'pi-whéé', or 'ja-coo-éé' ", a "very high 2-noted 'du-Twee' ", and "a slow, deliberate teeoopooee". This vocalization is often given for long periods. It also makes a " 'sew-kli' or 'chi-cli', and ated nasal 'hoint'or 'hoít' ".
ID text from Wikipedia, CC BY-SA 4.0
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Play today's Daily BirdPhotos and recordings are credited to their authors under the licence shown. Full profiles: Slaty Spinetail and Sooty-fronted Spinetail.