I know they've pretty much wiped out the Liguus populations at Castellow
Hammock (a nature preserve) in Dade County, Florida (SE of Miami).

As of a couple of years ago they supposedly were not in Everglades National
Park, but the general description of the places your friend saw decimated
snail populations could certainly fit some of the places I see them there.

On Tue, Apr 9, 2024 at 9:20 PM Alan Kabat <
[log in to unmask]> wrote:

> From the *Zoological Record*, here are three recent papers about this
> invasive flatworm (and several other invasive species), from the Caribbean
> and Florida:
>
> Lopez L., et al., 2022. Tree snails in South Florida: ongoing research and
> conservation concerns. Tentacle, 30: 17-19.
> https://www.hawaii.edu/cowielab/Tentacle/Tentacle_30.pdf
>
> Justine, J.-L., et al., 2021.  Presence of the invasive land flatworm *Platydemus
> manokwari *(Platyhelminthes, Geoplanidae) in Guadeloupe, Martinique and
> Saint Martin (West Indies). Zootaxa, 4951(2): 381-390.
> https://www.mapress.com/zt/article/view/zootaxa.4951.2.11/43386
>
> Brown, M.-D. et al., 2022. First record of exotic terrestrial flatworms
> (Tricladida: Geoplanidae) *Bipalium vagum *Jones & Sterrer, 2005 and *Dolichoplana
> striata *Moseley, 1877 with confirmation of *Platydemus manokwari *de
> Beauchamp, 1963 in Jamaica.  BioInvasions Records, 11(2): 373-382.
> https://www.reabic.net/journals/bir/2022/2/BIR_2022_Brown_etal.pdf
>
> These papers, and the sources cited, probably will be able to answer your
> questions -- although I doubt that there is currently any known way of
> eradicating them that would be effective as opposed to counterproductive.
>
> --Alan Kabat
>
> On Tuesday, April 9, 2024 at 08:18:00 PM EDT, Sylvia op facebook <
> [log in to unmask]> wrote:
>
>
> Dear Listers,
>
>
>
> I found the exotic New Guinean flatworm *Platydemus manokwari* on the
> Dutch Caribbean island Bonaire, and I worry because from literature is
> known that it did serious harm to indigenous terrestrial molluscs on
> several Pacific islands. Bonaire has a lot of endemic terrestrial species.
> The same flatworm is reported from Florida and has been occurring there for
> longer than on Bonaire. Someone visiting Florida recently told me that he
> found a lot of empty shells of “tree snails with nice colors” (I guess *Liguus
> *spec) along the ‘snail trail’ in Florida, filled with “worms” – and he
> saw nearly no live specimens of the snails. Also he told me that he saw
> numerous live tree snails only 2 years ago along the same trail. It is just
> one observation, but it sounds as something to worry about.
>
>
>
> Does anyone know more about the effects of this flatworm on terrestrial
> mollusks in Florida? Are there any publications about this subject? And if
> they form a threat, is there a way to eradicate them?
>
>
>
> I am also aware of the risks to human health, but that is not my question
> here.
>
>
>
> Thank you very much for your help in advance,
>
> Sylvia van Leeuwen
>
> [log in to unmask]
>
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