At 8 cm (3.1 in) in length, it is one of the two shortest birds native to Africa, alongside the tit hylia.

[2] The mouse-coloured penduline tit was formally described in 1882 by the German ornithologist Gustav Hartlaub under the binomial name Aegithalus musculus.

[3] The species is now placed in the genus Anthoscopus that was introduced in 1851 by the German ornithologist Jean Cabanis.

The specific epithet musculus is Latin meaning "little mouse".

[5] This species has an extensive range in Ethiopia, Kenya, Somalia, South Sudan, Tanzania, and Uganda, with an estimated global Extent of Occurrence of 550,000 km2.