The White-rumped Tanager is an unmistakable black and white tanager with black upperparts and lighter-colored underparts, white wing bars, and a conspicuous white rump (Isler and Isler 1999). Males and females are similar in plumage, but have strikingly different vocalizations. The two sexes often vocalize together in the form of a duet. Two subspecies are recognized; the northern subspecies has a supercilium, which is lacking in the southern subspecies. In addition, the southern subspecies has an amber-colored chin and throat.
The White-rumped Tanager has black upperparts, a white patch on its rump, and light underparts, making it distinctively different from other black and white tanagers. The White-rumped Tanager also sings a more distinct, intricate song than many other species (Ridgely and Tudor 2009). For these reasons, it is not easily mistaken for any other species within its range.
Adults: Both sexes have the same black and white pattern (Sick 1993, Isler and Isler 1999) with black upperparts, white rumps, white wing bars, and rufous throats (Sick 1993). They have lighter underparts and short, thick bills (Isler and Isler 1999).
Juveniles: Juveniles have the same color pattern as adults, except they have brown, rather than black, upperparts and do not have rufous throats (Sick 1993, Isler and Isler 1999). Like adults, they have a white rump and wing bars (Ridgely and Tudor 1989, Isler and Isler 1999).
Little information. White-rumped Tanager juveniles have duller plumages than their adult counterparts. After their second molt, they acquire the darker adult plumage (Isler and Isler 1999).
Iris: brown (Ridgely and Tudor 1989)
Bill: black (Ridgely and Tudor 1989)
Tarsi: gray (Ridgely and Tudor 1989)
Total length: 16 cm (Isler and Isler 1999)
Mass, males: mean 31.6 g (n=6; Silva et al. 1997)
Mass, females: mean 31.3 g (n=8; Silva et al. 1997)