About Gynacantha millardi Fraser, 1920
Gynacantha millardi Fraser, 1920 is a slender dragonfly. Its abdomen is not constricted at the third segment, and the species has an overall uniform pale green base coloration. Its thorax is green; the upper surface of its abdomen ranges from pale brown to reddish brown, while the sides of abdominal segments 1–3 are grass green. This species can be told apart from other Gynacantha species by its unmarked frons: Gynacantha dravida, Gynacantha basiguttata, and Gynacantha subinterrupta all have a T-mark on the frons. It resembles G. bayadera in size, shape, and color, but can be differentiated by the lack of the prominent third abdominal segment constriction that is present in G. bayadera. G. millardi was previously considered a synonym of G. bayadera, but Priyadarshana et al. (2015) demonstrated that it is a valid species, noting that its earlier synonymization was based on an incorrect interpretation of a 1930 remark by Lieftinck. Currently, Gynacantha millardi is known to occur in India and Sri Lanka. The widespread G. bayadera occurs from Northeast India to South China and northern New Guinea. It is unclear whether these two species have overlapping distributions, and a review of existing records of both species from the Indian subcontinent is needed. Gynacantha millardi is crepuscular, and flies low in shady habitats.
