The widespread distribution with population variations has led to nearly thirty subspecies being described. The nominate population is found in peninsular India (excluding the Western Ghats). The population in the northern Eastern Ghats is paler and has been called as pallidum while a well marked dark form occurs in the southern Western Ghats which has been named granti (includes olivaceum). The western Himalayas population is punctatum (includes jonesi) and in the east is mandellii which has streaking on the back and nape apart from having call differences. In the east of India, south of the Brahmaputra River occurs chamelum while ripley is found in a small region in eastern Assam (Margherita). Further east in Manipur is vocale and pectorale in Arunachal Pradesh and northern Burma with stageri further south, followed by hilarum, victoriae and minus. Further east are found shanense, subochraceum, insularum, indistinctum, chtonium, elbeli, acrum, oreum, dusiti, vividum, ubonense, euroum, deignani, dilloni and smithi. Several others have been described and many populations are difficult to assign to subspecies. This is the type species for the genus Pellorneum and its generic placement is assured although other species currently included in the genus may be reassigned.