Pomarea castaneiventris = Monarcha castaneiventris (chestnut-bellied monarch)
Source The birds of New Guinea and the adjacent Papuan islands : including many new species recently discovered in Australia. v.2 (Plate 57). https://biodiversitylibrary.org/page/53843925
Author William Matthew Hart (1830–1908)
Date between 1875 and 1888

Source: https://commons.wikimedia.org/wiki/File:Pomarea_castaneiventris_-_The_Birds_of_New_Guinea.jpg

The chestnut-bellied monarch (Monarcha castaneiventris) or chestnut-bellied monarch-flycatcher is a species of bird in the family Monarchidae. It is endemic to the Solomon Islands.

Order: Passeriformes
Family: Monarchidae
Genus: Monarcha
Species: Monarcha castaneiventris Verreaux, 1858