Butterflies of
North America
Falcate
Orange-tip
Anthocharis
midea
HÜBNER, 1809
Family - PIERIDAE
subfamily -
PIERINAE
tribe
- ANTHOCHARIDINI
Anthocharis midea, Tennessee, USA ©
Ken Childs
Introduction
The genus
Anthocharis comprises of 17 known
species, popularly known as Orange-tips. The most common and
widely distributed species is
Anthocharis cardamines,
which is found across the whole of temperate Europe, in Asia north
of the Himalayas, and eastward to China and Japan.
There are 4
other species found in Europe, plus 5 which are confined to the
Far East, and 7 species that are restricted to various parts of
North America. There is also another species -
A. belia, which is found in north
Africa ( and is only very distantly related to the Arabian and
sub-Saharan Orange tips which are members of a different genus -
Colotis ).
Only the males of
Anthocharis have the orange apex.
Most of the species have rounded forewings, but in
midea ( and in the Chinese
A. scolymus ) the apex is falcate.
The underside hindwings of all Anthocharis
species are cryptically patterned with greenish blotches or
stripes on a white ground colour, providing superb camouflage when
the butterflies are at rest on umbellifer flowers or on foliage.
The green colour is an optical illusion caused by a mixture of
black and yellow wing scales.
Anthocharis midea is widespread in
the USA, east of the Great Plains.
Habitats
This species is
found in forest glades, woodland edge habitats, and sheltered
damp meadows, at altitudes between sea level and about 1000m.
Lifecycle
The egg is
skittle-shaped, and laid singly on the flower stalks of the
larval foodplants. When first laid it is yellowish-green, but
soon changes to a dull orange colour, then becomes greyish a day
or two prior to hatching.
The caterpillar
when fully grown is olive green, dotted with tiny black points.
It has a broad creamy white lateral stripe, and a blue-edged
orange mid-dorsal stripe. The caterpillars feed on the seed
pods, stems and leaves of various Cruciferae including
Arabidopsis,
Arabis, Barbarea,
Cardamine,
Sisymbrium, Dentaria and
Lepidium. According to Scott
females also sometimes oviposit on Draba
and Capsella, but the resulting
larvae die soon after hatching. The caterpillars of all
Anthocharis species turn
cannibalistic if they encounter others of their own or any other
species - a practice that probably evolved because a single
specimen of the foodplant is only sufficient to support a single
caterpillar to maturity.
The pupa is
boomerang-shaped, with a long pointed head-capsule, and is
straw-coloured, with tiny black dots on the abdomen and wing
cases. It is vertically attached by the tip of the abdomen to a
twig or stem, and secured by a silk girdle around the waist. The
pupa hibernates overwinter.
Adult behaviour
Males patrol
relentlessly back and forth across their habitat in search of
virgin females, pausing here and there for a few seconds to take
nectar from their larval foodplants and other spring flowers.
Females also commonly nectar at the same species of flowers,
between egg-laying bouts. Both sexes roost overnight on
flowerheads, or on the upper surface of the leaves of bushes,
always choosing sheltered locations.
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