Distribution of the newly invasive New Guinea flatworm Platydemus manokwari (Platyhelminthes: Geoplanidae) in Thailand and its potential role as a paratenic host carrying Angiostrongylus malaysiensis larvae

Abstract

Invasive species constitute one of the most serious threats to biodiversity and ecosystems, and they potentially cause economic problems and impact human health. The globally invasive New Guinea flatworm, Platydemus manokwari (Platyhelminthes: Geoplanidae), has been identified as a threat to terrestrial biodiversity, particularly soil-dwelling native species (e.g. molluscs, annelids and other land planarians), and is listed among 100 of the world's worst invasive alien species. We report here, for the first time, P. manokwari occurrences in many locations throughout Thailand, using voluntary digital public participation from the social network portals associated with the Thailand Biodiversity Conservation Group and collections of living flatworm specimens. Mitochondrial cytochrome c oxidase subunit I (COI) sequences confirmed that all collected flatworms were P. manokwari and placed them in the "world haplotype" clade alongside other previously reported specimens from France, Florida (USA), Puerto Rico, Singapore, French Polynesia, New Caledonia, and the Solomon Islands. In addition, infective stage larvae (L3) of the nematode Angiostrongylus malaysiensis were found in the flatworm specimens, with a 12.4% infection rate (15/121 specimens examined). Platydemus manokwari occurrence in Thailand and its capacity to carry L3 of Angiostrongylus should be of concern to biodiversity conservation and human health practitioners, because this invasive flatworm species may be involved in the life cycle of angiostrongylid worms in Thailand.

Trying to take over the world: Potential distribution of Obama nungara (Platyhelminthes: Geoplanidae), the Neotropical land planarian that has reached Europe

“…), and more recently to Europe, North America, and Asia (Chaisiri et al., 2018; Hu et al, 2019; Justine, Winsor, Gey, Gros, & Thévenot, 2014; Justine et al., 2015). This planarian has caused significant damage to native snail populations in some invaded areas (Iwai, Sugiura, & Chiba, 2010; Sugiura, 2009; Sugiura, Okochi, & Tamada, 2006), and has been recognized as a paratenic host for the nematode Angiostrongylus cantonensis (Chen, 1935), which causes angiostrongyliasis (Asato et al., 2004; Chaisiri et al., 2018). Despite not being in the blacklist, another planarian species, the ‘hammer‐head planarian’ Bipalium kewense Moseley, 1878 is one of the most popular invasive planarians, perhaps for being one of the species that has virtually ‘conquered the world’.…”

First Record of Presence of the Invasive Land Flatworm <em>Platydemus manokwari</em> (Platyhelminthes, Geoplanidae) in Guadeloupe

“…The land flatworm Platydemus manokwari is a highly invasive species, listed among the "100 World's Worst Invader Alien Species" (Lowe et al 2000). Originally described from a locality in Papua New Guinea (de Beauchamp 1962), it has been recorded since in many islands of the Pacific Ocean, Australia, and, more recently, in Porto Rico in the Antilles, Florida in mainland USA (Justine et al 2015;Justine et al 2014), and mainland Asia in Hong Kong (Hu et al 2019) and Thailand (Chaisiri et al 2019). We report here its presence in Guadeloupe, an island of the Caribbean arc.…”

Obama chez moi! The invasion of metropolitan France by the land planarian Obama nungara (Platyhelminthes, Geoplanidae)

“…Clearly, records from citizen science should be considered with this bias in mind. Cultural differences between urban and rural populations in France are probably relatively minor compared to what can be found in other countries; a recent study in Thailand found that more reports of P. manokwari were received from the great shore cities than from the inland (Chaisiri et al, 2019), which should be, in our opinion, interpreted more as a geographical/cultural bias, rather than a preferred location of the species.…”

“…Many reports of new invasions by various species of land flatworms are published every year (Chaisiri et al, 2019;Hu et al, 2019;Jones, 2019;Justine et al, 2018aJustine et al, , 2019Prozorova & Ternovenko, 2018;Rodríguez-Cabrera & Torres, 2019;Soors et al, 2019; Week #21: Paper in PeerJ Figure 22 Reports of alien land planarians in 2018 in France (all species including Obama nungara), shown as weekly numbers. The total number of records in 2018 was 262.…”