Placobdelloides siamensis is a species of blood-feeding jawless leech in the family Glossiphoniidae.

[1][2] It is commonly known as the Siam shield leech and is a prevalent ectoparasite on Malayemys turtles but has a range of Geoemydidae hosts.

In high numbers it can cause severe anaemia and malnutrition which can lead to the death of its host.

[3] The species was first described as Hemiclepsis siamensis by Oka in 1917[1] then transferred by Sawyer to his new genus Placobdelloides in 1986.

[4] The type host is the Black Marsh Turtle, Siebenrockiella crassicollis.