The speckled mousebird was formally described in 1789 by the German naturalist Johann Friedrich Gmelin in his revised and expanded edition of Carl Linnaeus's Systema Naturae.

[2] Gmelin based his description on the "Coliou rayé" that had been described in 1778 by the French polymath Comte de Buffon from a specimen that had been collected near the Cape of Good Hope in South Africa.

[3] Seventeen subspecies are recognised:[4] The speckled mousebird is about 35 cm (14 in) long, with the tail comprising approximately half the length, and weighs about 57 g (2.0 oz).

Being in a torpid state could make them easy prey, but the large groups are apparently effective enough to deter most nocturnal predators.

The nest is a large (for the bird) and untidy cup made of vegetable and animal material (sometimes including cloth and paper) and is constructed by both the male and female.