The following diagnostic characters enable TPP to be distinguished from other closely related species:
Fig. 4. Head of the tomato-potato psyllid (Bactericera cockerelli) showing the short genal cones and distinctive white markings on the vertex. Note: the shape, size and intensity of the white markings on the head and body varies between individuals.
Fig. 5. The antennae of the tomato-potato psyllid (Bactericera cockerelli) have a disc-shaped rhinarium on the 4th segment (circled). Note: the antennae also have a striped appearance due to the lighter colouration of the basal two-thirds of segments 3- 8.
Fig. 6. Terminalia of the tomato-potato psyllid (Bactericera cockerelli). Male terminalia are characterised by a proctiger with relatively wide posterior lobes, a paramere that is more slender in the apical half and a subtriangular distal segment on the aedeagus. Female terminalia have fewer diagnostic characters but the top margin of the proctiger is almost straight.