Opal-rumped Tanager Tangara velia

  • Order: Passeriformes
  • Family: Thraupidae
  • Polytypic: 4 subspecies
  • Authors: Evan Lerman and Kevin J. Burns
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Appearance

Distinguishing Characteristics

The Opal-rumped Tanager is a medium sized species of the genus Tangara with a longer, thinner bill than most of species of TangaraThe plumage is predominately blue and black. The crown and back are black, with a bright opalescent rump. The head and underparts are deep iridescent blue (or the underparts are silvery blue in cyanomeleana). Contrasting with these colors are a reddish chestnut lower belly and crissum. Some of these colors are shared with close relatives such as the Opal-crowned Tanager (Tangara callophrys) and the Turquoise Tanager (Tangara mexicana).

Similar Species

A very similar species to the Opal-rumped Tanager is the Opal-crowned Tanager (Tangara callophrys); the distributions of these two species overlap in western Amazonia. Like the Opal-rumped Tanager, the Opal-crowned Tanager is characterized by a slender bill, predominantly blue plumage, and a bright yellow, opalescent rump. The two birds differ in that the Opal-crowned Tanager has a distinct opal crown and eyebrow as well as a black lower belly, rather than the distinctive chestnut lower belly of the Opal-rumped Tanager (Restall et al. 2007). Another similar species is the Turquoise Tanager (T. mexicana), which possesses similar plumage coloration, but which has a blue rump and a light yellow or white under belly (Ridgely and Tudor 1989, Hilty 2003). During field identification, the chestnut belly often is the easiest mark to distinguish the Opal-rumped Tanager from other similar species.

Detailed Description

Adults: Sexes are similar in both size and plumage, but females have slightly duller coloration than males (Restall et al. 2007).

Adult, male: Tangara velia velia - Overall black and opalescent yellow on the dorsal side and deep blue-purple and chestnut on the ventral side. The bill is black, longer, and thinner than that of most Tangara species. The crown, nape, back, scapulars and tail are black. The chin, supercilium, auriculars and malar are bright cerulean blue while the throat is deep purplish-blue with an irregular black band across it. The rump is an opalescent straw yellow that becomes a greenish opal more distally before turning bluer on the uppertail coverts. Primaries, secondaries, and secondary coverts are black with deep purplish blue leading edges. The breast, sides, and flanks are purplish blue and the belly and undertail coverts are reddish chestnut (Restall et al. 2007).

Adult, female: Similar to the male, but tend to be duller and slightly paler than males (Restall et al. 2007).

Juvenile: Similar to females but the face is much darker (Restall et al. 2007).

Molts

In general, most tanagers only molt once a year (Isler and Isler 1987), and this prebasic molt likely occurs afterthe breeding season (Isler and Isler 1987, Ryder and Wolfe 2009). However, many species have been found to breed in subadult plumage (Isler and Isler 1987). In many species of Tangara, the preformative molt is partial (Ryder and Wolfe 2009). Species in the genus Tangara generally acquire adult plumage after the postjuvenile molt (Skutch 1954: 261). Although a subadult plumage is described for Tangara velia (Isler and Isler 1987), more specific information on molt and its timing is not available for this species.

Bare Parts

Iris: Bright brown

Bill: Black

Tarsi and toes: Black


Bare parts color descriptions taken from Restall et al. (2007).

Measurements

Total length: 12-14 cm (Isler and Isler 1987), 14 cm (Hilty 2003), 14.5 cm (Ridgely and Greenfield 2001)

Mass, both sexes:

T. v. velia- 21.0 g (n = 36; Pearson et al. 1971)


T. v. iridina- 21.0 g ± 2.0 g (19.0-23.0 g; n = 11) (Isler and Isler 1987)

The following statistics are comparative measurements of bill length, bill width, tail length, and wing-length between two differing groups of Opal-rumped Tanagers which may warrant separate species status: subpecies distributed in Amazonia (velia, signata, and iridina) and cyanomelaena of southeastern Brazil (Pinto de Assis et al. 2008):


             Bill length (mm): Amazonian subspecies and cyanomelaena

Amazonian

Mean

SD

Min

Max

n

cyanomelaena

Mean

SD

Min

Max

n

Males

14.20

0.64

12.65

15.60

32

Males

16.18

0.78

15.00

17.10

12

Females

14.24

0.99

12.90

15.75

8

Females

15.32

0.73

14.20

16.50

7

Bill width (mm): Amazonian subspecies and cyanomelaena

Amazonian

Mean

SD

Min

Max

n

 cyanomelaena

Mean

SD

Min

Max

n

Males

4.36

0.41

3.90

5.25

35

Males

4.73

0.30

4.20

5.25

13

Females

4.47

0.46

3.50

4.85

8

Females

4.74

0.30

4.15

5.00

7


Tail length (mm): Amazonian and cyanomelaena

Amazonian

Mean

SD

Min

Max

cyanomelaena

Mean

SD

Min

Max

n

Males

48.51

2.90

42.00

55.50

36

Males

52.54

1.95

49.00

56.0

13

Females

48.00

3.02

43.50

51.50

8

Females

50.13

2.54

45.50

54.0

7

Wing length (mm): Amazonian subspecies and cyanomelaena

Amazonian

Mean

SD

Min

Max

n

cyanomelaena

Mean

SD

Min

Max

n

Males

71.04

3.18

60.85

76.60

36

Males

72.42

1.93

69.50

70.80

13

Females

68.72

2.50

66.10

70.55

8

Females

69.42

1.92

66.50

71.55

8

Recommended Citation

Lerman, E. and K. J. Burns (2012). Opal-rumped Tanager (Tangara velia), version 1.0. In Neotropical Birds Online (T. S. Schulenberg, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/nb.oprtan1.01