Cycle of the Pearl-bordered
The shiny cream conical
shaped eggs are laid singly or sometimes in pairs on the underside of a
the food plant from about mid-May or early June, hatching in c.2 weeks.
The larva measures up to 25 mm in length when fully grown. The
body is velvety black with a grey-black
spots along the spiracular area. It has sub-dorsal and lateral
branched spines (scoli). Those in the sub-dorsal
area have a contrasting yellow base, but prior to the
final moult become black like all the others.
The larva feeds by day on the young and tender leaves of Common Dog
Violet in June until the end of
August when as the 4th instar it enters hibernation.
on the ground sheltered by leaf debris and sometimes hidden in a dead rolled violet leaf.
It emerges from
hibernation during the first warm days days of March when the larva resumes
its growth and feeding throughout
Pupation begins around mid-April among low vegetation of its
food plant or among ground debris.
The pupa is suspended from a silk pad in a silken structure loosely spun on a leaf or
the dense ground vegetation.
This stage lasts up to 19 days.
Adults emerge in mid-May and are on the wing from mid-May to
mid-June. During this time they mate and
feed. Both sexes are avid feeders of nectar with a preference
for purple and yellow flowers. The female
begins to lay her eggs about mid-May.
© DHardiman 2005