The two species of sittella are small passerines which resemble nuthatches in appearance.
The wings are long and broad, and when spread have clearly fingered tips.
The family has a generally weak flight, which may explain their inability to colonize suitable habitat on islands like Tasmania.
 The legs are short but they have long toes, but in spite of their lifestyle they show little adaptation towards climbing.
They have short tails and are between 10 and 14 cm in length  and 8 and 20 g in weight, the black sittella tending to be slightly larger and heavier.
The bill is dagger shaped in the case of the black sittella and slightly upturned in the varied sittella.
The plumage of the black sittella is mostly black with a red face; that of the varied sittella is more complex, with the numerous subspecies having many variations on the theme.
The sexes of some subspecies have entirely black heads, other white, and others dark crowns and paler throats.
The backs of most subspecies are grey with darker wings, and the undersides are generally streaked or white.
All sittellas exhibit some sexual dimorphism in plumage.
The two species of sittella are small passerines which resemble nuthatches in appearance. The wings are long and broad, and when spread have clearly fingered tips. The family has a generally weak flight, which may explain their inability to colonize suitable habitat on islands like Tasmania.  The legs are short but they have long toes, but in spite of their lifestyle they show little adaptation towards climbing. They have short tails and are between 10 and 14 cm in length  and 8 and 20 g in weight, the black sittella tending to be slightly larger and heavier. The bill is dagger shaped in the case of the black sittella and slightly upturned in the varied sittella. The plumage of the black sittella is mostly black with a red face; that of the varied sittella is more complex, with the numerous subspecies having many variations on the theme. The sexes of some subspecies have entirely black heads, other white, and others dark crowns and paler throats. The backs of most subspecies are grey with darker wings, and the undersides are generally streaked or white. All sittellas exhibit some sexual dimorphism in plumage.
Sittella