Blue cotingas (Cotinga) are medium sized, stocky cotingas with short, wide bills; the wings are relatively long, but the tail and tarsi are relatively short. Male blue cotingas are notable for the brilliant body plumage, which in all species is bright blue, and which is a structural color, and for modified outer primaries. Female blue cotingas are quite different, and are primarily brown. Male Lovely Cotinga is mostly turquoise blue, with a purple throat and a large purple patch on the belly; the wings and tail are mostly black. The female is dark brown above, heavily scaled with whitish. The underparts of the female are whitish, spotted with brown.
Lovely Cotinga is similar to several other species in the genus, but does not overlap geographically with any other species of Cotinga. The male Turquoise Cotinga (Cotinga ridgwayi), of the Pacific coast of southern Costa Rica and western Costa Rica, is very similar, but has a slightly larger purple belly patch, and is more heavily spotted above with black; female Turquoise Cotinga is much buffier than female Lovely Cotinga. Also very similar is Blue Cotinga (Cotinga nattererii) of eastern Panama and northwestern South America. Male Blue Cotinga is slightly darker than male Lovely Cotinga, usually is more spotted above with black, and has a narrow black ring around the eye. Female Blue Cotinga is browner, and less scaled or spotted, than female Lovely Cotinga.
The following detailed description is based on Ridgway (1907) and Kirwan and Green (2011):
Adult male: Upperparts generally rich bright blue (the tone varying depending the angle of the light relative to the observer); blue slighter deeper on the crown. Feathers of upperparts are black subterminally, but the black typically is concealed. Lesser and median wing coverts rich bright blue. Wings otherwise black, the greater and primary coverts and secondaries edged with blue or greenish blue, these edgings broader on the tertials. Feathers of uppertail coverts elongated, covering much of the tail, especially medially. Rectrices black, rectrices edged with greenish blue or bluish green. Malars and lower half of the auriculars glossy purplish black or blackish purple; chin, throat and upper breast dark purple. Lower breast, flanks and undertail coverts rich bright blue, with an oval patch of rich purple on the belly.
Primary 7 is short, and the outer webs of primaries 8 and 9 are sinuated (Snow 1982).
Adult female: Upperparts generally dark grayish brown, the feathers with terminal whitish margins, producing a scalloped pattern; these whitish feather tips are broadest on the rump and uppertail coverts. Rectrices dusky grayish brown, very narrowly edged with green or greenish gray. Wings dusky grayish brown; lesser coverts usually tinged with greenish, the median coverts sometimes also tinged with greenish; greater coverts and secondaries edged with pale grayish brown or buffy (edgings broader and more whitish on the tertials). Underparts dull white, feathers (except on the lower belly and undertail coverts) with a central dusky grayish brown spot, these spots larger and darker on the breast and sides.
Immature: Similar to adult female, secondaries and greater wing coverts tipped and edged with cinnamon buff, and feathers of crown tipped with pale brown (rather than whitish).
Little information. Molt noted on three specimens collected in January and February in Guatelama (Land 1963). The duration of molt, across the genus Cotinga, was estimated as 100 days (Snow 1976).
Iris: dark brown
Bill: gray to black
Tarsi and toes: gray to black
Bare parts color data from Snow (1982) and Kirwan and Green (2011).
Total length: 18-19 cm (Howell and Webb 1995, Kirwan and Green 2011), 19 cm (Stiles and Skutch 1989)
wing length: male, range 112-124 mm (n = 19; Kirwan and Green 2011)
male, mean 117.0 mm (range 113-120 mm, n = 11; Snow 1982)
female, range 109-120 mm (n = 8; Kirwan and Green 2011)
female, mean 114.6 mm (range 110-118 mm, n = 5; Snow 1982)
tail length: male, range 58-73 mm (n = 20; Kirwan and Green 2011)
male, mean 66.4 mm (range 63-69 mm, n = 11; Snow 1982)
female, range 63-72 mm (n = 8; Kirwan and Green 2011)
female, mean 68.0 (range 66-70, n = 5; Snow 1982)
bill length: male, range 14.12-16.54 mm, measured from base (n = 20; Kirwan and Green 2011)
male, mean 10.6 mm, measured from posterior edge of nares (range 10- 11 mm, n = 5; Snow 1982)
female, range 15.41-17.02 mm, measured from base (n = 8; Kirwan and Green 2011)
female, mean 11.6 mm, measured from posterior edge of nares (range 11.5-12 mm, n = 5; Snow 1982)
tarsus length: male, range 18.25-22.22 mm (n = 10; Kirwan and Green 2011)
male, mean 21.5 mm (range 20.5-23 mm, n = 11; Snow 1982)
female, range 21-24 mm (n = 4; Kirwan and Green 2011)
female, mean 22.3 mm, range 22-23 mm (n = 5; Snow 1982)
Mass: male, mean 74 g (n = 2; 73, 75 g; Snow 1982); female, mean 69.8 g (n = 3, range 66-73.5 g; Snow 1982). Tashian (1952) also reported a body mass of 73.5 g for one female, but we do not know if this record is among the three values for females reported by Snow (1982).