The red-billed leiothrix (Leiothrix lutea) is a member of the family Leiothrichidae, native to southern China and the Himalayas. Adults have bright red bills and a dull yellow ring around their eyes. Their backs are dull olive green, and they have a bright yellow-orange throat with a yellow chin; females are somewhat duller than males, and juveniles have black bills. It has also been introduced in various parts of the world, with small populations of escapees having existed in Japan since the 1980s. It has become a common cagebird and amongst aviculturists it goes by various names: Pekin robin, Pekin nightingale, Japanese nightingale, and Japanese (hill) robin, the last two being misnomers as it is not native to Japan (although it has been introduced and naturalised there).