The small group of the genus Ips placed at the end of Dr. Swaine's key seems to have a character not found elsewhere in the genus. The epistomal region, in the males, is elevated and often has a dense brush of hairs which make the elevation look greater than it really is. However, this brush is often rubbed until it has entirely disappeared. This has apparently given rise to the idea that two entirely different females are associated with the males in the same gallery.