Special agents from the U.S. Fish and Wildlife Service and U.S. Postal Inspection Service arrested Sven Koppler when he traveled to Los Angeles to meet with an associate, the U.S. Attorney's Office in Los Angeles said.
Koppler, 37, of Wachtberg, Germany, is accused of sending more than 500 live tarantulas through the mail. The spiders included 22 Mexican red-kneed tarantulas, a protected species whose formal name is Brachypelma smithi.
Authorities say Koppler was paid $300,000 for the arachnids.
If found guilty, he could serve up to 20 years in prison and pay a fine of as much $250,000.
The arrest was the culmination of an investigation known as "Operation Spiderman."
Authorities began tracking Koppler in March, when they discovered about 300 live tarantulas during a routine search of an international package.
Agents then engaged Koppler in a sting operation, ordering and receiving dozens of live tarantulas, authorities said.