Siebenrockiella crassicollis (commonly known as black marsh turtle, smiling terrapin, and Siamese temple turtle, among others) is a freshwater turtle endemic to Southeast Asia. One of the two species classified under the genus Siebenrockiella in the Geoemydidae family. They are classified as Vulnerable by the IUCN, being one of the several Southeast Asian turtle species heavily exploited for the international wildlife trade, particularly for food and traditional medicine in the Chinese markets.