Nymphs show a pointed head (characteristic of Scaphytopius) and a bicolored body, with brownish sides and a pale, whitish middle.

For diagrams of this species, see: Zahniser.

This species also resembles S. latus. In S. latus, the head is about two times as long as the width between the eyes; in S. acutus, the head is around 1.5 times as long as the width between the eyes. S. latus also tends to be slightly larger, has less distinct markings on the head, has shorter male plates, and the pregenital sternite of the female is longer. (Hepner 1947)

S. acutus is described as being one of the most variable species in the genus, with color ranging from very dark (almost black) to a light fulvous, and the crown can vary in length (Hepner 1947).

S. acutus is an important pest species for many plants, all important agricultural crops. It is "a vector of six viruses: alfalfa witches' broom in Washington and Utah, western X-disease virus of peach and cherry, eastern X-dizease virus of peach and cherry, little cherry virus in British Columbia, clover phyllody virus in eastern Canada, and the western straing of North American aster yellows virus in eastern Canada" (UK). For more information, see the cited link.