The Namaqua warbler (Phragmacia substriata), also known as the Namaqua prinia or white-breasted prinia, is a small passerine bird, a cisticolid warbler and the sole member of the genus Phragmacia. It was formerly placed in the genus Prinia, but was found to be sufficiently distinct to warrant a genus of its own.
The Namaqua warbler is 12–13 cm long, with short rounded wings, a long tail, strong legs and a short straight black bill. The head has a whitish eyebrow and the upperparts are otherwise a rich russet brown. The throat and lower face are whitish with no streaking, and the breast is white with faint streaking. The rear flanks are buff. The long, brown tail is typically cocked up at an angle. The feet and legs are pinkish-brown, and the eye is brown. The sexes are identical, but juveniles are duller than the adults. The calls include a high-pitched treeep-treep-trrrrrr.
The Namaqua warbler can only be confused with the Karoo prinia, but that species has a shorter, less whispy tail, duller brown back and buff tips to the undertail feathers.