Comparative morphology of the mouthparts of Brontocoris tabidus and Podisus nigrispinus (Heteroptera: Pentatomidae):...

The predator Brontocoris tabidus (Signoret 1852) (Hemiptera: Pentatomidae) exhibits greater predatory efficiency than Podisus nigrispinus (Dallas 1851) (Hemiptera: Pentatomidae). This study aimed to assess whether the superior performance of B. tabidus is related to differences in the morphology of its mouthparts. The rostrum, as well as the mandibular and maxillary stylets of adult insects, were analyzed using scanning electron microscopy. No structural differences were observed between the mouthparts of the two predators. Both species have asymmetrical maxillary stylets with tapered tips and small lateral teeth near the apical end. The mandibular stylets are symmetrical, with large apical teeth arranged in an arrow-like pattern, and deep grooves along their surface. Both the teeth and grooves are oriented toward the insect's head. The mandibular stylets and arrow-shaped structures are proportionally longer in B. tabidus, which may confer greater attack efficiency and could be associated with the larger body size of this predator.