Chestnut-bellied monarch

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.

Chestnut-bellied monarch
Chestnut-bellied monarch (below); illustration by Keulemans, 1879
Conservation status
Least Concern  (IUCN 3.1)[1]
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Passeriformes
Family:	Monarchidae
Genus:	Monarcha
Species:	M. castaneiventris
Binomial name
Monarcha castaneiventris Verreaux, 1858
Subspecies
See text

Subspecies

Five subspecies are recognised:^[2]

• M. c. erythrostictus (Sharpe, 1888) – Buka Island, Bougainville Island, Shortland Islands and Fauro Island (north Solomon Islands)
• M. c. castaneiventris Verreaux, J, 1858 – Choiseul Island, Santa Isabel, Florida Islands, Guadalcanal, Savo Island (north of northwest Guadalcanal) and Malaita (central, southeast Solomon Islands)
• M. c. obscurior Mayr, 1935 – Russell Islands (central south Solomon Islands)
• M. c. megarhynchus Rothschild & Hartert, EJO, 1908 – Makira (southeast Solomon Islands)
• M. c. ugiensis (Ramsay, EP, 1882) – Ugi Island and Olu Malau Islands (or Three Sisters) (north of Makira), and Owaraha (Santa Ana) and Santa Catalina (or Owariki) (east of Makira; southeast Solomon Islands

M. c. erythrostictus has sometimes been treated as a separate species, the Bougainville monarch

Behaviour and ecology

In 2009, it was reported that a genetic change in some members of this species caused their colouration and songs to be different from other members of the species. As a result, members in one group did not recognize members in the other, so the two groups became reproductively isolated from each other. It was thought that over time, this could eventually lead to the creation of a new species, and that this was an example of biological evolution.^[3]