A continued slew of discoveries of New Guinea flatworms, on the list of the world's 100 worst invasive alien species, has been reported in several provinces and the capital.
The New Guinea flatworm, also known as Platydemus manokwariis, is a species of large, predatory land flatworm. It has been accidentally introduced to the soil of many countries around the world, including the US and now Thailand.
The flatworms also were found at a farm in Nakhon Ratchasima's Wang Nam Khieo district, raising fears the species might invade the Unesco World Heritage site of Dong Phayayen-Khaoyai Forest Complex.
Nonn Panitvong, the founder of the Siamensis Biodiversity Conservation Group, said Thursday he has received more information from members of the group about discoveries of the flatworms.
"I am concerned over the report of New Guinea worms being discovered at a farm in Wang Nam Khieo district which is not far from Khao Yai National Park.
"There is a strong possibility they might get into the park, posing serious problems to the ecological system and ruining the forest's fertility," he said.
"The discovery of New Guinea flatworms in several locations means they arrived in the country many years ago and no one realised."
He said the worms have spread further than had been expected after the first was identified in Pathum Thani province last month.
Mr Nonn said the reports he obtained stated the worms had been found in Kasetsart University in Bang Khen district, near Krungthepkreetha Golf Club in Saphan Sung district and in some places on Charoen Krung Road in the capital.
In the provinces, apart from Nakhon Ratchasima, they were also found at Prince of Songkla University in Songkhla's Hat Yai district, Sattahip district in Chon Buri and Saraphi district in Chiang Mai.
Mr Nonn said the flatworm likes eating earthworms and shells, with many international studies finding this could lead to its prey going extinct. This is the reason why it has been categorised as one of the world's 100 worst invasive alien species.
The flatworm's natural habitat is New Guinea in the Pacific Ocean, and the shipping of plants and wood is assumed to have caused their spread to Thailand.