Download Recognising green snail

Recognising green snail
How to identify and report Cantareus apertus
Green snail (Cantareus apertus), a plant pest exotic to
Victoria, was found in the state for the first time in 2011.
What does green snail look like?
This factsheet describes the appearance and behaviour of
green snail and compares it to other snail species which
may be found in crops or gardens.
Mature green snails have an olive-green shell and white flesh.
They are intermediate in size between the smaller vineyard
snail and white Italian snail and the larger common garden
snail, rarely exceeding 25 mm in shell diameter.
Green snail
Other snails of crops and gardens
Adult green snail (shell diameter up to 25 mm)
Common garden snail adult (shell diameter over 25 mm)
White Italian snail (shell diameter about 20 mm)
Adult green snail just prior to dormancy
Vineyard snail (shell diameter about 15 mm)
Juvenile green snail (shell diameter about 15 mm)
Green snail hatchling (shell diameter about 8 mm)
Small pointed snail (shell diameter about 6 mm)
Recognising green snail
How does green snail behave?
Green snail has been found to damage a wide range of
plants, including cabbages, cauliflowers, lettuces, peas,
beans, wheat, lupins, pasture grasses and native plants. It
thrives in dense grass and also inhabits areas of natural bush.
When preparing for dormancy, green snails seal the opening
to their shell with a solid skin (see image below). This skin is
dissolved when the snails re-activate following autumn and
winter rains.
The damage caused by green snail is similar to that of
common garden snail – feeding on the surfaces of young
leaves, often only penetrating shallowly and leaving a
‘windowpane’ effect. Older snails eat holes in the leaves and
may reduce them to veins only.
Green snail with shell sealed for dormancy
Following re-activation, green snails lay their eggs in the soil
during May or June and the young snails appear in early
winter. Green snails can breed quickly and reach densities
of up to 1000 young snails per square metre.
Green snail damage in a lucerne crop
Green snails spread through the movement of infested plant
material e.g. in hay bales, nursery stock or harvested
vegetables.
Like the white Italian snail and the common garden snail, the
green snail remains dormant through the summer (December
– March) in dry situations and does not pose a risk to crops.
Unlike the other snails, it burrows into the soil before
becoming dormant.
As their summer dormancy approaches, green snails tend to
darken in colour, making them more similar to common
garden snails.
The higher temperatures of summer are not the only cause of
dormancy in green snails. It is also caused by factors such as
day length, so the snails will become dormant even if the soil
is cooled by irrigation.
Published by the Victorian Government Department of Environment and Primary Industries
Melbourne, August 2013
© The State of Victoria Department of Environment and Primary Industries Melbourne 2013
This publication is copyright. No part may be reproduced by any process except in accordance
with the provisions of the Copyright Act 1968.
ISBN 978-1-74326-482-9 (print)
ISBN 978-1-74326-483-6 (pdf)
www.depi.vic.gov.au
Green snail eggs (actual diameter about 4 mm)
Reporting
If you suspect you have found green snail, please contact
DEPI:

phone 136 186

email [email protected] (please send
photographs if possible).
Accessibility
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Customer Service Centre 136 186, email [email protected] (or relevant
address), via the National Relay Service on 133 677 www.relayservice.com.au
Disclaimer
This publication may be of assistance to you but the State of Victoria and its employees do not
guarantee that the publication is without flaw of any kind or is wholly appropriate for your
particular purposes and therefore disclaims all liability for any error, loss or other consequence
which may arise from you relying on any information in this publication.