It is endemic to western Angola and only known from the holotype collected from Quissange.

The holotype was lost in the fire of the Natural History Museum of Lisbon in 1978.

[2][3][4] The validity of this species is in question; it might be a synonym of Leptopelis bocagii or considered a nomen dubium.

The feet are relatively long, more than half the length of the head and body.

[6] Leptopelis marginatus is associated with the Great Escarpment of Angola,[4] but the original species description does not include any habitat or ecological information.