Carya-illinoinensis
Guides
Monellia caryella
Blackmargined Pecan Aphid, Black Margined Aphid
Monellia caryella, commonly known as the blackmargined pecan aphid, is a small sap-feeding insect and significant pest of pecan (Carya illinoinensis) orchards in North America. Adults are distinguished by a prominent black stripe along the outer margin of their wings, which are held flat over the body. Populations typically increase from June to August, then decline after approximately three weeks; outbreaks on most cultivars usually subside without causing measurable damage, though the 'Cheyenne' cultivar is notably susceptible. The species is subject to substantial mortality from entomopathogenic fungi, particularly during autumn when environmental conditions favor fungal growth.