Moustached kingfisher

The two subspecies are:

• A. b. bougainvillei can be found in Bougainville Island, Papua New Guinea. The immature plumage is unknown. However, the adult male has dark tawny-orange forehead, crown, cheeks and mantle. A narrow, delineated purple-blue line runs from behind the eye to the nape, and a broader one forms a long moustache stripe from the lower mandible, curving under and behind the cheeks and ear coverts. The upper back, scapulars, wings, side of rump, and tail are a dark purple-blue, while the lower back and centre of rump and uppertail-coverts are a brilliant pale azure blue. The underparts are orange-rufous, paler on the chin, belly and undertail-coverts than on the breast and flanks. The bill is red and the eyes are dark brown. The legs and feet have brown nails. The adult female is like the male, except that the upper back, scapulars, and tertials are olive green and the head is a darker rufous, merging into the mantle. The wingspan of a male is 127–136 mm and the female's is 127–133 mm. The tail's length of a male is 85–95 mm while the female's is 91–96 mm. The length of the bill on a male ranges from 49–58 mm, while on the female it ranges from 46–51 mm. The tarsus of both male and female ranges from 19–21 mm. The recorded weight ranges from 160 to 215 g.
• A. b. excelsus can be found in Guadalcanal in the Salomon Islands. The adult female is more olive-green on the back, scapulars, and tertials, and has much paler orange underparts than the other subspecies. An immature male has the upper back, scapular, and tertials very dark olive-green.

The moustached kingfisher is considered an endangered species by the International Union for Conservation of Nature, and its population is thought to be decreasing.