The genus Ixulus resembles Yuhina very closely but has the bill shorter, deeper and more curved at the tip ; the rictal bristles and hairs over the bill are weaker and less developed.
Key to Species and Subspecies.
A. Nape white I. occipitalis, p. 321.
B. Nape without any white.
a. A distinct collar round neck.
a1. A rusty-yellow collar on hind neck.
a2.. Strise confined to scapulars and [p. 322.
upper back; darker I. flavicollis flavicollis,
b2. Striae over the whole back to rump;
paler I. fl. baileyi, p. 323.
b1. A bright chestnut collar on hind
neck I. fl. harterti, p. 323.
b. No collar on hind neck. [p. 324.
c1. Crown and back brown I. humilis humilis,
d1. Crown brown, back greyish I. h. clarkii, p. 324.