4-10-2026 MONTE CORONA, VALENCIA - GRASS EGGAR MOTH (Lasiocampa trifolii)

The grass eggar moth (Lasiocampa trifolii) is a hairy, reddish-brown or straw-yellow moth belonging to the family Lasiocampidae.

Physical Description and Appearance

• Wingspan: Measures between 40 and 55 mm, with females notably larger than males.

• Markings: Features a curved cross-line on the forewings and a distinct central white spot.

 • Subspecies: Includes the pale form known as the pale grass eggar (Lasiocampa trifolii subspecies flava) found in Kent.

• Caterpillars: Thickly haired, growing up to 65 mm, and display ruddy brown, yellow, or black segments.

Habitat and Distribution

• Locations: Found across Europe, inhabiting coastal dunes, maritime cliffs, and acid heaths.

• Food Plants: Caterpillars feed on grasses, heather, bramble, and willow.

Life Cycle and Behavior

• Flight Period: Adults fly primarily from August to September and are active at night, showing strong attraction to light.

• Overwintering: The species overwinters in the egg stage near the ground before hatching in spring.

• Pupation: Larve spin tough cocoons low to the ground amongst grass stems and leaf litter.