The International Ornithological Congress, the Clements taxonomy, and the South American Classification Committee of the American Ornithological Society assign it these six subspecies:[1][2][3] However, BirdLife International's Handbook of the Birds of the World (HBW) treats these taxa as six of ten subspecies of what it calls the white-backed fire-eye (Pyriglena leuconata).

The western fire-eye is 16 to 18 cm (6.3 to 7.1 in) long and weighs 26 to 36 g (0.92 to 1.3 oz); the subspecies' weights apparently vary.

Males of all the subspecies are mostly glossy black with a partially hidden white patch between their scapulars and blackish gray underwing coverts.

Subspecies P. m. pacifica females have a plain face, dark reddish yellow-brown upperparts, and grayish olive-brown underparts.

Their diet includes a wide variety insects (e.g. orthopterans, beetles, ants, wasps, and adult and larval moths and butterflies), other arthropods such as spiders and centipedes, and small lizards up to about 11 cm (4.3 in) long.

The nest is an "oven" hidden among vegetation on the ground; the male does most of the construction with the female contributing towards the end.

The song of male western fire-eyes is "a medium-length (e.g. 2 seconds) series of evenly paced short whistles that usually rise and fall slightly in pitch, sometimes also in intensity" and appears to vary somewhat among the subspecies.

[6] In Peru the four subspecies apparently all make the same calls, "a quiet, puttering pit'cht'cht and a low prrt; also a ringing, chattered tutututututu, a sharp pick and a mewed, descending eeww-eww".

[9] The IUCN follows HBW taxonomy and so has not separately assessed the western, Tapajos, and East Amazonian fire-eyes.

[6][7] Its range includes several large protected areas and "it is more capable than many forest birds of persisting in older second growth".