About Machaeropterus regulus (Hahn, 1819)
The kinglet manakin, scientifically named Machaeropterus regulus (Hahn, 1819), measures 9 to 10.3 cm (3.5 to 4.1 in) long and weighs 6.4 to 12.5 g (0.23 to 0.44 oz). This species is sexually dimorphic. Adult males have bright red coloring on the forehead, crown, and nape. The remainder of their face is grayish olive-green. Their upperparts and tail are olive-green. Their wings are mostly olive-green, with white tips on the secondaries. Their chin and throat are plain whitish. The rest of their underparts are whitish, with thin red-brown stripes across the breast, belly, and flanks. Their thighs are red. Adult females have no red on their head, and their face is grayer than the male's. The streaks on their underparts are only present on the belly and flanks. Both sexes have a deep red or red-brown iris, a dark horn to blackish upper mandible (maxilla), and a paler lower mandible. Males have purplish beige to bright pink legs and feet; female legs and feet are often duller and paler. Juveniles of both sexes resemble adult females. The kinglet manakin is distributed in coastal southeastern Brazil, from northeastern Bahia south at least to northern Rio de Janeiro state. There are scattered records of the species south and inland of its main contiguous range. It inhabits humid lowland forest, including secondary forest and restinga. Most of its range lies between sea level and about 200 m (700 ft) in elevation, but it can be found locally as high as about 600 m (2,000 ft).
