Cheshire
Macro-Moths - Convolvulus Hawk-moth
The
Convolvulus Hawk-moth - Agrius convolvuli Linnaeus
Imago / Adult:
The adult moth (imago) is large and varies between 94
and 120 mm wingspan. The ground colour is a mixture of greys and grey-browns
with dirty pink markings on the hind wings and pink horizontal stripes
on the abdomen.. It is an immigrant moth which only occasionally rears
a brood in Britain. It cannot stand the cold and damp of British winters
in any form and as a consequence has not been able to establish itself
itself in this country. It appears most years from mid to late June
and can last as long as late August or early September. It is most
often to be seen visiting heavily scented garden flowers such as Nicotiana
and is occasionally taken at light. In Cheshire it is probably most
often found resting on the outside of greenhouses - Why? - who knows!
There is usually at least one specimen reported in either Cheshire
or South Lancashire every year and occasionally several - one was
even reported a few years ago on the steps leading up to Liverpool
Museum. The moth occurs most commonly in southern coastal counties
but has been found throughout Britain.
Larva:
The larvae are also large, usually 90 to 105 millimetres
in length. The ground colouration of the body is usually brown (see
picture above) though a rarer green form is also known to occur. Both
the green and brown forms have the ground colouration speckled with
black with oblique yellowish-white stripes. The spiracles are large,
distinctive and black, whilst the larval horn on the top of the eleventh
segment is large, curved and also a shiny black colour. All of the
larvae of both colour forms start off life as bright green in the
early instars.
Foodplant(s):
The larvae usually feed on a variety of bindweeds (e.g.
Field Bindweed and Great Bindweed). However, as can be seen from the
photograph above they will successfully take Coleus plants
as an alternative
Overwintering:
The moth does not overwinter in Britain being unable to stand our
cold and especially damp conditions. Whether this will change with
'Global Warming' we shall have to wait and see.
Breeding:
In captivity the larvae do best if kept warm, often the 'airing
cupboard' is the best - they seem to eat faster when kept in the
dark as well. The major problem with these conditions is condensation.
The larvae must be kept as dry as possible which means lining the
box with tissue and replacing it at least once a day.