Hair-crested Drongo (Dicrurus hottentottus) - HBW 14, p. 213

Taxonomy: Corvus hottentottus Linnaeus, 1766, Cape of Good Hope; error = Chandernagor [Chandannagar], West Bengal, India.
Formerly considered conspecific with D. menagei, D. sumatranus, D. densus and D. bracteatus; DNA studies have indicated close taxonomic relationship of present species with D. balicassius, D. bracteatus and D. megarhynchus, and all of these, together with D. montanus and the aforementioned species, could be part of a superspecies containing eight species. Two Philippine races, striatus and samarensis, included within present species although having some similarity also to neighbouring D. balicassius (tail shallowly forked, outer rectrices flat, iris brown), are placed by some authors in D. bracteatus (despite absence of some specific characteristics of latter); inclusion within present species (or D. bracteatus) could be argued on basis of velvety black mantle (D. balicassius has whole upperside, including tail, very strongly glossed), but, on other hand, both races lack some other characters specific to present species (i.e. frontal hair-like filaments, large tail with end of outer feathers twisting inwards and outwards). Further taxonomic research essential in order to clarify true relationships among all of these species. Race banggaiensis sometimes synonymized with pectoralis, and in the past with leucops. Clinal decrease in size from N to S, birds in C India being similar to those of Myanmar and Thailand, intermediate between those of Himalayan foothills and those of S India (extreme length of male tail 149-164 mm in Himalayas, 132-155 mm in C India, 114-128 in SW India). Nominate race intergrades with brevirostris from S China (W Yunnan) and N Myanmar E to N Vietnam. Proposed race chrishna (described from Nepal foothills), allegedly larger than specimens from C & S India, is regarded as not distinguishable from nominate; termeuleni (Thousand Is, in Jakarta Bay, in W Java) considered inseparable from jentincki, but insufficient evidence available, and further study required. Race banggaiensis has sometimes been merged with leucops or pectoralis. Fourteen subspecies currently recognized.