Tim Collins, Department of Biological SciencesFlorida International University

Alície Warren, Conservation and Restoration BiologistMiami-Dade County Environmentally Endangered Lands Program and Parks, Recreation & Open Spaces Department

New Guinea flatworm, Platydemus manokwari, in Florida: Status and Threats to Native Land Snails

What is Platydemus manokwari?

Shinji Sugiura, Ogasawara Islands Japan

Recognizing Platydemus flatworms

Leigh Winsor

eyespotssnout

“D” shaped in cross-section

Size

Justine et al. PeerJ 2015

Appearance and Reproduction

Justine et al. PeerJ 2015 New Caledonia, Cocoon photo by Leigh Winsor

Egg capsules called cocoons

Pair of Platydemus flatworms at Kingman preserve (Redlands, FL) that appear to be mating (parallel, stacked)

Eye spots and snout

Feeding & Prey

Justine et al. PeerJ 2014

Concerns regarding Platydemus flatworms:

• In other regions where introduced, it is considered the cause of extinction and/or dramatic decline of native species, particularly snails (e.g. Cowie, 2008)

• Is considered one of the World’s 100 worst invasive species (Global invasive Species Database)

• Can carry Angiostrongylus (rat lungworm disease), which infects humans

First report of Platydemus manokwari

Travels of Platydemus manokwari

Justine et al. PeerJ 2015

How is Platydemus spreading?• Reported rate of natural dispersal limited, between 30 (Winsor, 1990) and 180 Meters per year (Muniappan, 1987) over suitable habitat/conditions.• Other routes are accidental or intentional introduction.

Platydemus flatworms reported in South Florida, January 2015

CastellowHammock Preserve

Castellow-Ross Hammock Preserve Complex in South Miami-Dade County

Castellow 33 Preservein August / September 2015

Sample of +300 Liguus sp. and other snails from Platydemus flatworm feeding aggregations in

Castellow 33 Preserve August-September 2015

Alície Warren

Genetic Analysis confirms ID of Platydemus manokwarifrom Castellow 33, south Miami-Dade, West Palm

Beach and Sanibel Island.

Miami-Dade County Environmentally Endangered Lands Preserve Nearby:

Continued Monitoring of Miami-Dade County Environmentally Endangered Lands Preserve:

Tim Collins

Different Color Morphs

Tim Collins

Tim Collins

Tim Collins

Tim Collins

Tim Collins

Tim Collins

July 16th 2017: Reported Range for Platydemus flatworms in Florida - Greatly Expanded Since 2015

Coming to Your Neighborhood?(or maybe already there)

Tim Collins

2017 Monitoring Surveys

Tim Collins

Tim Collins

Recent Kills of Tree Snails Continue

Tim Collins

• Seeing fewer snails than you used to?

• Search in warm moist conditions -after rain ideal.

• A full 1-4 hours after dark best, but can be found during the day (moist places, early morning rains, etc.).

• In leaf litter, under/around rocks logs, tree trunks, i.e. where there are snails.

If you think you have one, let us know! Collinst@fiu.edu or nam@miamidade.gov.

Wondering if you’ve got Platydemus flatworms?

Priorities: What Needs to be Done• Determine full extent and continuity of Platydemus flatworm range, especially

near natural areas with diverse snail faunas, including Liguus and Orthalicus spp. and other at risk species.

- Establish monitoring/bait stations in sensitive natural areas- Develop other rapid methods of assaying presence of Platydemus (e.g. Dogs)- Check Platydemus populations for presence of parasites/pathogens.

• Assay population health of Liguus and Orthalicus spp. in natural areas:– Determine specific south Florida natural areas at high risk for invasion by Platydemus flatworms (e.g, areas

in EVER, BICY, BNP, Fakahatchee, Panther NWR, 10,000 islands, MDC PNAs, etc.) (from regular heavy public visitation, areas of current/proposed restoration including new planting installations and/or use of heavy equipment, and/or frequent vehicle/contractor traffic, etc.)

– Determine Protected Natural Areas with unaffected colonies of native tree snails where invasion possibilities by Platydemus flatworms could be minimized.

• Determine precise human-mediated mechanisms of spread and intervene if possible (e.g. Phytosanitary measures).

• Halt movement of plants / soil etc. from infected areas to uninfected natural areas

Acknowledgements:• Support from: Florida Fish & Wildlife Conservation Commission, Wildlife

Impact Management Section

• Sarah Funck, Jason Wagman, David Cook, Jim Duquesnel, Florida Fish & Wildlife Conservation Commission

• Andrew Derksen, Florida Department of Agriculture and Consumer Services, Division of Plant Industry, Cooperative Agricultural Pest Survey -South Florida Region

• Eduardo Salcedo, Natural Areas Management Miami-Dade Parks, Recreation and Open Spaces Department

• Alex Salcedo, TERRA Environmental Research Institute, Miami-Dade County Public Schools

• Mary Yong Cong, Science GALS Program Miami, Division of Plant Industry, Florida Department of Agriculture and Consumer Services

Any Questions?