Cabera exanthemata

Distinguished from similar Cabera species by the specific pattern and number of wavy transverse lines; C. pusaria (Common White Wave) has fewer and less distinct waves. The combination of pale ground color with multiple fine, parallel, wavy brown lines is characteristic. In North America, it can be separated from native geometrids by its distinctive lined pattern and overall pale appearance. Genitalia examination may be required for definitive separation from closely related species.

Adults have pale whitish or cream-colored wings with fine, wavy, brownish transverse lines that give the species its common name. The wings are relatively broad and rounded, with a wingspan typically ranging 28–33 mm. The pattern consists of several parallel, undulating lines across both forewings and hindwings, with a small discal spot often present. The body is slender and matches the pale wing coloration. Antennae are filiform in both sexes.

Deciduous and mixed woodlands, forest edges, hedgerows, and scrubland. Adults are frequently found in areas with abundant birch (Betula) and alder (Alnus), the larval host plants. The species occurs from lowland to montane elevations.

Native to the Palearctic region, including Europe, North Africa, and Asia to Japan. Introduced and established in North America. Present throughout Belgium including all administrative regions. The species has been documented across the Near East.

Adults are active from May to August in temperate regions, with peak flight typically in June and July. In favorable conditions, a partial second generation may occur in late summer. The species overwinters as a pupa.

Larvae feed on leaves of birch (Betula spp.) and alder (Alnus spp.). Adults do not feed.

• Betula - larval host plantprimary host
• Alnus - larval host plantsecondary host

Univoltine or partially bivoltine depending on latitude and climate. Eggs are laid on host plant leaves. Larvae feed externally on foliage, resting along leaf edges or twigs. Pupation occurs in a loose cocoon among leaf litter or in soil. The pupal stage overwinters.

Adults are nocturnal and attracted to light. They rest with wings held flat or slightly overlapping, displaying the characteristic wavy pattern. When disturbed, they may drop to the ground and remain motionless. Larvae are twig-mimics, resting with body extended at an angle from branches.

Larvae function as folivores on birch and alder, contributing to nutrient cycling in woodland ecosystems. The species serves as prey for various insectivores including birds, bats, and predatory arthropods.

Occasionally encountered by moth enthusiasts and in light-trapping surveys. Not considered an economic pest despite larval feeding on birch and alder. Used as an indicator species for woodland habitat quality in some ecological monitoring programs.

• Cabera pusariaSimilar pale coloration and wavy lines, but has fewer, less pronounced waves and slightly different wing shape; genitalia differ
• Lomographa bimaculataWhite geometrid with different pattern (two prominent spots rather than multiple wavy lines)

• geometrid
• woodland
• birch feeder
• palearctic
• introduced North America

• BugGuide
• GBIF taxonomy match
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life