Royal Sunangel

The royal sunangel is 10 to 12 cm (3.9 to 4.7 in) long and weighs 3.4 to 4.5 g (0.12 to 0.16 oz). Its black bill is short and straight. Both subspecies are strongly sexually dichromatic. The adult males are unique among genus Heliangelus: Their bodies are entirely dark blue. The nominate's plumage is slightly shiny, with significant iridescence only on its forecrown (just above the bill). H. r. johnsoni is intensely iridescent all over and especially so on the crown, throat, and upper breast. The male nominate's tail is dark metallic violet-purple and that of johnsoni is metallic indigo. Voice: The royal sunangel has a wide variety of vocalizations. During aerial displays males give "a series of emphatic 'tseep' notes". Two agonistic males "uttered an endless, thin, high-pitched jumble of 'jijijit'jijit'jijit'jijiji…' notes". Calls given while feeding are "a repeated short dry and emphatis 'tsik' or 'tsawk'". One male gave "a sharp, high-pitched, fast 'chichúp chúp!