Life
Cycle of the Marsh
Fritillary
Ovum:
The glossy pale-yellow spheres are flattened above and below and
are c.0.8 mm in height. They are laid in
batches of up to several hundred on the underside
of large leaves of the foodplant in June and hatch
within
30-40 days. Egg clusters change their colour in time becoming a
reddish-brown and eventually a
purplish-brown and can be fairly easily seen on the leaves.
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© DHardiman 2004 |
Larva:
The fully fed larva can reach 30 mm in length. The body is
black with short branched black spines and
has bands of white speckling on the dorsal surface and along the line of
the spiracles.
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Marsh Fritillary larvae emerging from web |
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Late instar larva
© DHardiman 2005 |
The head is black and the prolegs are reddish-brown .
From late June to August the gregarious young larvae spin a silk web on a couple
of leaves of the foodplant under which
they live, feed and moult.
After the third moult they immediately go into hibernation after
spinning themselves into a silken ball among
vegetation, either close to or on the ground, where they overwinter.
But they emerge to bask outside the web on sunny warm days in
February and March returning to dormancy
in poorer weather conditions.
They split into smaller groups as they grow larger and are feeding
alone by late April. By the end of April
they are fully grown and disperse to pupate. This larval stage lasts c.10 months.
Pupa:
They pupate on stems and foliage suspended by a silk pad on which they
attach their cremasteral hooks.
Butterflies emerge in 16-26 days.
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© DHardiman 2002
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Adult:
The adults begin to emerge by the end of May or early June
and are on the wing until early July. The male
survives an average of 4 days and the female 3 days. During this
time they feed, mate and the female
lays her eggs. The Marsh Fritillary keeps office hours,
flying from 9.00 a.m. to 5.00 p.m.
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© DHardiman 2004
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