Tangara azul sobre vegetación de galerÍa en Río Gallinas, Municipio de Tamasopo San Luis Potosi, Huasteca Potosina
The blue-gray tanager is 16–18 cm long and weighs 30–40 g. Adults have a light bluish head and underparts, with darker blue upperparts and a shoulder patch colored a different hue of blue. The bill is short and quite thick. Sexes are similar, but the immature is much duller in plumage.
The Blue-grey Tanager (Thraupis episcopus) is a medium-sized South American songbird of the Tanager family, Thraupidae. Its range is from Mexico south to northeast Bolivia and northern Brazil, all of the Amazon Basin, except the very south. It has been introduced to Lima (Peru). On Trinidad and Tobago, this bird is called Blue Jean.