Subspecies
Exhibits considerable individual variation and, in particular, extreme geographical variation in plumage, especially in east of range. Appreciable size variation also exists, being largest in northern and west. Subspecies guttacristatus has sometimes been treated as separate species, as also has strictus. Further research may reveal that some of the more distinctive taxa, especially those isolated on islands, have evolved into full species, but present knowledge insufficient to enable accurate assessment.
Proposed subspecies sultaneus (northern India, Nepal), grandis (Polillo, in Philippines) and maculiceps (Basilan, in Philippines) considered too poorly differentiated to warrant recognition.
The following 13 subspecies are recognised:
socialis Koelz, 1939 - Western coast of India. Considered by some authors to be a subspecies of Greater Flameback (Chrysocolaptes guttacristatus).
guttacristatus (Tickell, 1833) - North-western India and Nepal east to southern China (Yunnan) and south to Thailand and Indochina. Considered by some authors to be a distinct species, Greater Flameback (Chrysocolaptes guttacristatus).
stricklandi (E. L. Layard, 1854) - Sri Lanka. Considered by some authors to be a distinct species, Greater Sri Lanka Flameback (Chrysocolaptes stricklandi).
chersonesus Kloss, 1918 - Peninsular Malaysia south to Sumatra and western Java.
andrewsi Amadon, 1943 - North-eastern Borneo (from around Sandakan to Sebatik I). Considered by some authors to be a subspecies of Greater Flameback (Chrysocolaptes guttacristatus).
strictus (Horsfield, 1821) - Eastern Java. Considered by some authors to be a distinct species, Javan Flameback (Chrysocolaptes strictus).
kangeanensis Hoogerwerf, 1963 - Coastal eastern Java, Bali and Kangean Is. Considered by some authors to be a subspecies of Javan Flameback (Chrysocolaptes strictus).
haematribon (Wagler, 1827) - Northern Philippines (Luzon, Polillo, Marinduque and Catanduanes). Considered by some authors to be a distinct species, Luzon Flameback (Chrysocolaptes haematribon).
erythrocephalus Sharpe, 1877 - Balabac, Palawan and Calamian Group. Considered by some authors to be a distinct species, Red-headed Flameback (Chrysocolaptes erythrocephalus).
xanthocephalus Walden and E. L. Layard, 1872 - Ticao, Masbate, Panay, Guimaras and Negros. Considered by some authors to be a distinct species, Yellow-faced Flameback (Chrysocolaptes xanthocephalus).
lucidus (Scopoli, 1786) - Basilan and western Mindanao (Zamboanga Peninsula).
montanus Ogilvie-Grant, 1905 - Mindanao (except west) and Samal.
Similar Species
Common Flameback (Dinopium javanense) which has a shorter bill, a pointier crest, black hind-neck, and dark iris.
References
See References.