This insect was first described in California in 1892 by the American entomologist Frank Ellsworth Blaisdell.

[1] He named it Scymnus lophanthae, and thought it was a native American species.

Unbeknown to him, the beetle was an introduced species, and at about the same time, it was described in its native Australia by the Australian entomologist Thomas Blackburn, who gave it the name Rhizobius toowoombae.

The head and prothorax are reddish-brown, as is the underside, both being densely covered with short hairs of two lengths.

[3] It was introduced into California in 1892 in an attempt to control the olive scale (Saissetia oleae).