Appearance
The chestnut munia is 11–12 cm in length. The adult has a stubby pale grey-blue bill, black head, and brown body, with a brick red patch on the lower back, visible only when it flies. Some races also have a black belly.The sexes are similar, but immature birds have uniform pale brown upperparts, lack the dark head and have white to pale buff underparts.

Naming
The chestnut munia has several subspecies that are recognized as followed:⤷ "Lonchura atricapilla atricapilla"
⤷ "Lonchura atricapilla rubroniger"
⤷ "Lonchura atricapilla sinensis"
⤷ "Lonchura atricapilla formosana"
⤷ "Lonchura atricapilla deignani"
⤷ "Lonchura atricapilla brunneiceps"
⤷ "Lonchura atricapilla jagori"
⤷ "Lonchura atricapilla selimbauensis"
⤷ "Lonchura atricapilla obscura"
⤷ "Lonchura atricapilla batakana"

Habitat
The chestnut munia is a small gregarious bird which feeds mainly on grain and other seeds. It frequents open grassland and cultivation. The nest is a large domed grass structure in a bush or tall grass into which 4-7 white eggs are laid.References:
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