The Kilombero Weaver lives in Tanzania's Kilombero River floodplain. Breeding males are bright yellow with a black face pattern, and the birds nest on reeds.
A breeding male has a bright yellow crown, nape, and underparts, with a small black mask extending from the eye to the throat and edged narrowly in chestnut. Females and non-breeding males are duller and lack the black face.
Its food includes flowering and fruiting grass heads; the source also lists dried fish and household refuse. Nests are attached to reed stems, often over water in seasonally flooded areas.
An extinction-risk assessment has not been added yet.