Ploughshare Tortoises are among the rarest species on earth, with a dwindling population of about 400 in northwestern Madagascar.
The smugglers — a 38-year-old Thai man and a 25-year-old woman who had flown from Madagascar to Suvarnabhumi International Airport — also had 21 Radiated Tortoises, which are also critically endangered.
Earlier this year the Thai man was arrested on a different wildlife smuggling charge.
The tortoises can command high prices in the animal black market in South East Asia.
Earlier the same day, authorities at the airport found 300 Indian Star Tortoises and 10 Black Pond Turtles when they inspected an unclaimed bag. Traffic notes that the Indian Star Tortoise is heavily traded as an exotic pet despite it being illegal to ship the species from its habitat in India, Sri Lanka, and Pakistan.
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