Leptoglossus occidentalis (Coreidae) 

the leaf-footed bug 

 

Insect: 

Adult Leptoglossus. Observe features distinguishing this insect as a hemipteran, i.e. basal part of wing thickened and leathery, distal part membranous. These insects have piercing and sucking mouthparts.  When insect is not feeding, the feeding tube is carried between the base of the legs. Nymphs are smaller editions of adults (gradual metamorphosis). Both adults and nymphs do damage. Observe features distinguishing it as a leaf-footed bug, i.e. tibia of hind legs enlarged and flattened to look like a little leaf. Adult is reddish brown and up to 18 mm long. Adults overwinter in tree crevices to escape the weather and emerge in May or June.

Damage: 

Adult Leptoglossus feeding on cone. No external damage is visible on the cones. Both adult and nymph stages insert their long proboscises into cones to suck juices from the seeds (bug remains on outside of cone). Heavy feeding can cause up to 41% loss of seed crop in Douglas-fir.

Principal Hosts: 

Douglas-fir, ponderosa pine, and incense-cedar. 

Economic Importance: 

Significant losses in California: a major seed orchard pest in B.C. 

References and Links: 

EAG: 545-546, 548-549;

Fact sheet. 

Additional Images: 

Leptoglossus first nymphal instars hatching. Leptoglossus nymphs fully emerged from eggs. Leptoglossus later nymphal instar feeding on cone. X-ray of Douglas-fir seeds showing reduced seed yield.