Species: Holly Blue (Cetastriba argiolus britanna)
Family: Hairstreaks, Coppers and Blues (LYCAENIDAE)
Category: Butterflies & Moths
Location: NW
A. Butterflies & Moths
B. Hairstreaks, Coppers and Blues (LYCAENIDAE)
This is a diverse group of colourful butterflies. The hairstreaks get their name from a thin white line on the underside of the wings. Female blues are often more brown than blue, and the Brown Argus is not blue at all.
C. Holly Blue (Cetastriba argiolus britanna)
This butterfly has two broods a year, and is on the wing from April until September, although preferring to feed in tree canopies on aphid honeydew rather than on wildflowers. The black border markings distinguish it from the Common Blue, the female Holly Blue being blue rather than brown. Single eggs of the Spring brood are laid beneath Holly buds, but those of the Summer brood mainly on Common Ivy. The caterpillars are green, although variable in pattern. The chrysalis of the second brood may hibernate.
Images
Holly Blue
This butterfly has two broods a year, and is on the wing from April until September, although preferring to feed in tree canopies on aphid honeydew rather than on wildflowers. This photograph shows it seeking a suitable location for its first brood egg in late April 2022.
Holly Blue
The Holly Blue is on the wing from April until September, although preferring to feed in tree canopies on aphid honeydew rather than on wildflowers.
True to its name, the Holly Blue lays its single egg on the flowers of Holly.
Holly Blue
The down-curved abdomen and the lowered antennae indicate the egg-laying posture of the Holly Blue, here - appropriately - on a Holly flower.
