The Guadalcanal moustached kingfisher was previously lumped together with A. bougainvillei, but is now regarded as a separate species.

[3] In 2015, a male specimen was killed and collected by a team from the American Museum of Natural History headed by Christopher Filardi.

[4] In 2024, one pair was recorded by a birdwatching tour group on Bougainville after ten days of searching.

[3] In the 1950s, local people observed holes in the riverbanks or in the ground in the forest, which were thought to be the nests of moustached kingfishers.

[3] It is capable of fast direct flight due to its rounded wings and a short tail.