The empodium of the foot of specimens of Heterosminthurus bears a prominent lamella. In Heterosminthurus novemlineatus, the longest setae on the inner side of the dens are about the same length as the mucro. In males, all of the setae between the eyes are of similar length.
Heterosminthurus novemlineatus is yellow in colour with several (usually nine hence novemlineatus) longitudinal bands of dark pigment. It is a rare species with a couple of records from northeast England, and a specimen collected from a mossy ditch in The Burren, Ireland reported by Lawrence (1961). There are no specimens in the NHML slide collection.