Geoica utricularia

Short-haired pistachio-grass aphid

Description

Geoica utricularia, commonly known as the short-haired pistachio-grass root aphid, is a sap-sucking insect that primarily targets Pistacia spp. in the Mediterranean and southwestern Asia. This aphid induces the formation of smooth, globular, yellowish galls on its host plant, usually near the base of leaflets, close to the main vein. The galls appear between July and October. After gall open, winged emigrants spread and establish colonies on the roots of various grasses like Agrostis, Avena, Festuca, and Hordeum. In regions where the primary host is absent, such as North America and parts of Europe, Geoica utricularia completes its entire life cycle on grass roots, reproducing parthenogenetically. This pest can cause significant damage to several Pistacia species and cultivated grasses, making it a concern for agriculture in these regions.

Symptom

The presence of Geoica utricularia is indicated by smooth, globular galls (creamy-white with brown-red base) on Pistacia leaves and deformities on grass roots, leading to weakened plant health and reduced crop quality.

Tree Species: Pistacia

Part of a plant- attacked: Leaf / Needle, Branch

Pest significance: Less harmful

Pest Category: Insects

Invasive Species: No

Present in EU: Yes