I have, quite recently,  found colonies of Theba pisana inland a bit
from San Diego, California.  The snails was supposed to have been
eradicated in the San Diego area, I believe, in the 1930's.  Clearly
that was not the case.

The two spots where I have encountereds these snails were disturbed
areas covered with shrubby weeds that  also contained other exotics-
Otala lactea, Helix aperta, and Rumina decollata.  One of these spots
had been imfested predominantly with Otala lactea with minor amounts of
Theba pisana.  In the last two years, the population has become
predominantly Theba with the Otalas becoming less abundant.   Can anyone
explain this phenomenon?

You can contact me privately for more information or samples of shells
from these localities.


Phil Liff-Grieff
[log in to unmask]

sophiev wrote:

> Hello,
>
> May I forward a question from Sylvain from France ? He's preparing a
> paper on Theba pisana and would like to have confirmation of the
> following :
>
> Theba pisana has been introduced in California at the beginning of
> last century but it is now officially eradicated : is it right ?
> Is it possible to find it anywhere else in the States ?
>
> Sylvain thinks Theba pisana did exist in New Zealand but cannot find
> any paper which can confirm that. Do you know any ?
>
> He suspects the specie's geographical range includes :
> - Mediterranean costs
> - Atlantic coasts from Morocco to Netherlands.
> - North Atlantic Islands : England, Ireland, The Azore, Madeira,
> Bermuda, Green Cape Islands, The Canaries, Salvages (???)
> - Switzerland
> - Saudi Arabian oasis
> - Australia
> - South Africa
> - Godan ? do you know where is this place ?
>
> Any information will be welcome !
>
> Thanks in advance
>
> Sophie